108 results on '"McCollum PT"'
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2. 10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1): a multicentre randomised trial
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Halliday, A, Harrison, M, Hayter, E, Kong, X, Mansfield, A, Marro, J, Pan, H, Peto, R, Potter, J, Rahimi, K, Rau, A, Robertson, S, Streifler, J, Thomas, D, Fraedrich G, Asymptomatic Carotid Surgery Trial Collaborative G. r. o. u. p., Schmidauer, C, Hölzenbein, Th, Huk, I, Haumer, M, Kretschmer, G, Metz, V, Polterauer, P, Teufelsbauer, H, Cras, P, Hendriks, J, Lauwers, P, Van Schil, P, de Souza EB, Dourado, Me, Gurgel, G, Rocha, Gm, Petrov, V, Slabakov, G, Cooper, Me, Gubitz, G, Holness, R, Howes, W, Langille, R, Legg, K, Nearing, S, Mackean, G, Mackay, M, Phillips, Sj, Sullivan, J, Wood, J, Erdelez, L, Sosa, T, Angelides, Ns, Christopoulos, G, Malikidou, A, Pesta, A, Ambler, Z, Mracek, J, Polivka, J, Rohan, V, Sevcik, P, Simaná, J, Benes, V, Kramár, F, Kaste, M, Lepäntalo, M, Soinne, L, Cardon, Jm, Legalou, A, Gengenbach, B, Pfadenhauer, K, Wölfl, Kd, Flessenkämper, I, Klumpp, Bf, Marsch, J, Kolvenbach, R, Pfeiff, T, Sandmann, W, Beyersdorf, F, Hetzel, A, Sarai, K, Schöllhorn, J, Spillner, G, Lutz, Hj, Böckler, D, Maeder, N, Busse, O, Grönniger, J, Haukamp, F, Balzer, K, Knoob, Hg, Roedig, G, Virreira, L, Franke, S, Moll, R, Schneider, J, Dayantas, J, Sechas, Mn, Tsiaza, S, Kiskinis, D, Apor, A, Dzinich, C, Entz, L, Hüttl, K, Jàrànyi, Z, Mogan, I, Nagy, Z, Szabo, A, Varga, D, Juhász, G, Mátyás, L, Hutchinson, M, Mehigan, D, Aladjem, Z, Harah, E, Elmakias, S, Gurvich, D, Yoffe, B, Ben Meir, H, Dagan, L, Karmeli, R, Keren, G, Shimony, A, Weller, B, Avrahami, R, Koren, R, Streifler, Jy, Tabachnik, S, Zelikovski, A, Angiletta, D, Federico, F, Impedovo, G, Marotta, V, Pascazio, L, Regina, G, Andreoli, A, Pozzati, E, Bonardelli, S, Giulini, Sm, Guarneri, B, Caiazzo, P, Mascoli, F, Becchi, G, Masini, R, Santoro, E, Simoni, G, Ventura, M, Scarpelli, P, Spartera, C, Arena, O, Collice, M, Puttini, M, Romani, F, Santilli, I, Segramora, V, Sterzi, R, Deriu, G, Verlato, F, Cao, Pg, Cieri, Enrico, De Rango, P, Moggi, L, Ricci, S, Antico, A, Spigonardo, F, Malferrari, G, Tusini, N, Vecchiati, E, Cavallaro, A, Kasemi, H, Marino, M, Sbarigia, E, Speziale, F, Zinicola, N, Alò, Fp, Bartolini, M, Carbonari, L, Caporelli, S, Grili Cicilioni, C, Lagalla, G, Ioannidis, G, Pagliariccio, G, Silvestrini, M, Palombo, D, Peinetti, F, Adovasio, R, Chiodo Grandi, F, Mase, G, Zamolo, F, Fregonese, V, Gonano, N, Mozzon, L, Blair, R, Chuen, J, Ferrar, D, Garbowski, M, Hamilton, Mj, Holdaway, C, Muthu, S, Shakibaie, F, Vasudevan, Tm, Kroese, A, Slagsvold, Ce, Dahl, T, Johnsen, Hj, Lange, C, Myhre, Ho, Gniadek, J, Andziak, P, Elwertowski, M, Leszczynski, J, Malek, Ak, Mieszkowski, J, Noszczyk, W, Szostek, M, Toutounchi, S, Correia, C, Pereira, Mc, Akchurin, Rs, Flis, V, Miksic, K, Stirn, B, Tetickovic, E, Cairols, M, Capdevila, Jm, Iborra Ortega, E, Obach, V, Riambau, V, Vidal Barraquer, F, Vila Coll, R, Diaz Vidal, E, Iglesias Negreia JI, Tovar Pardo, A, Iglesias, Rj, Alfageme, Af, Barba Velez, A, Estallo Laliena, L, Garcia Monco JC, Gonzalez, Lr, Corominas, C, Julia, J, Lozano, P, Marti Masso JF, Porta, Rm, Carrera, Ar, Gomez, J, Blomstrand, C, Gelin, J, Holm, J, Karlström, L, Mattsson, E, Bornhov, S, Dahlstrom, J, De Pedis, G, Jensen, Sm, Pärsson, H, Plate, G, Qvarfordt, P, Arvidsson, B, Brattström, L, Forssell, C, Potemkowski, A, Skiöldebrand, C, Stoor, P, Blomqvist, M, Calander, M, Lundgren, F, Almqvist, H, Norgren, L, Norrving, B, Ribbe, E, Thörne, J, Gottsäter, A, Mätzsch, T, Nilsson, Me, Lonsson, M, Stahre, B, Stenberg, B, Konrad, P, Jarl, L, Lundqvist, L, Olofsson, P, Rosfors, S, Swedenborg, J, Takolander, R, Bergqvist, D, Ljungman, C, Kniemeyer, Hw, Widmer, Mk, Kuster, R, Kaiser, R, Nagel, W, Sege, D, Weder, B, De Nie, J, Doelman, J, Yilmaz, N, Buth, J, Stultiens, G, Boiten, J, Boon, A, van der Linden, F, Busman, Dc, Sinnige, Ha, Yo, Ti, de Borst GJ, Eikelboom, Bc, Kappelle, Lj, Moll, F, Dortland, Rw, Westra, Te, Jaber, H, Manaa, J, Meftah, Rb, Nabil, Br, Sraieb, T, Bateman, D, Budd, J, Horrocks, M, Kivela, M, Shaw, L, Walker, R, D'Sa, Aa, Fullerton, K, Hannon, R, Hood, Jm, Lee, B, Mcguigan, K, Morrow, J, Reid, J, Soong, Cv, Simms, M, Baird, R, Campbell, M, Cole, S, Ferguson, It, Lamont, P, Mitchell, D, Sassano, A, Smith, Fc, Blake, K, Kirkpatrick, Pj, Martin, P, Turner, C, Clegg, Jf, Crosley, M, Hall, J, De Cossart, L, Edwards, P, Fletcher, D, Rosser, S, Mccollum, Pt, Davidson, D, Levison, R, Bradbury, Aw, Chalmers, Rt, Dennis, M, Murie, J, Ruckley, Cv, Sandercock, P, Campbell, Wb, Frankel, T, Gardner Thorpe, C, Gutowski, N, Hardie, R, Honan, W, Niblett, P, Peters, A, Ridler, B, Thompson, Jf, Bone, I, Welch, G, Grocott, Ec, Overstall, P, Aldoori, Mi, Dafalla, Be, Bryce, J, Clarke, C, Ming, A, Wilkinson, Ar, Bamford, J, Berridge, D, Scott, J, Abbott, Rj, Naylor, R, Harris, P, Humphrey, P, Adiseshiah, M, Aukett, M, Baker, D, Bishop, Cc, Boutin, A, Brown, M, Burke, P, Burnand, Kg, Colchester, A, Coward, L, Davies, Ah, Espasandin, M, Giddings, Ae, Hamilton, G, Judge, C, Kakkos, S, Mcguiness, C, Morris Vincent, P, Nicolaides, A, Padayachee, Ts, Riordan, H, Sullivan, E, Taylor, P, Thompson, M, Wolfe, Jh, Mccollum, Cn, O'Neill, Pa, Welsh, S, Barnes, J, Cleland, P, Davis, M, Gholkar, A, Jones, R, Jaykishnam, V, Mendelow, Ad, O'Connell, Je, Siddique, Ms, Stansby, G, Vivar, R, Ashley, S, Cosgrove, C, Gibson, J, Wilkins, Dc, Chant, Ad, Frankel, J, Shearman, Cp, Williams, J, Hall, G, Holdsworth, R, Davies, Jn, Mclean, B, Woodburn, Kr, Brown, G, Curley, P, Loizou, L, Chaturvedi, S, Diaz, F, Radak, D, Todorovic, Pr, Kamugasha, D, Baxter, A, Berry, C, Burrett, J, Collins, R, Crowther, J, Davies, C, Farrell, B, Godwin, J, Gray, R, Harwood, C, Hirt, L, Hope, C, Knight, S, Lay, M, Munday, A, Murawska, A, Peto, Cg, Radley, A, Richards, S., Cras, Patrick, van Schil, Paul, et al., Asymptomatic Carotid Surgery Trial (ACST) Collaborative Group, Halliday, A, Harrison, M, Hayter, E, Kong, X, Mansfield, A, Marro, J, Pan, H, Peto, R, Potter, J, Rahimi, K, Rau, A, Robertson, S, Streifler, J, Thomas, D, Adovasio, Roberto, and Asymptomatic Carotid Surgery Trial Collaborative, Group
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Male ,Time Factors ,medicine.medical_treatment ,Kaplan-Meier Estimate ,Carotid endarterectomy ,Aged ,80 and over ,Carotid Stenosis ,Endarterectomy ,Carotid ,Female ,Humans ,Incidence ,Middle Aged ,Primary Prevention ,Stroke ,Treatment Outcome ,Stroke/epidemiology ,law.invention ,Randomized controlled trial ,law ,Aged, 80 and over ,Endarterectomy, Carotid ,endarterectomy ,Carotid Stenosis/mortality ,Incidence (epidemiology) ,Carotid*/mortality ,General Medicine ,Carotid Stenosis | Internal Carotid Artery | Endarterectomy ,medicine.symptom ,medicine.medical_specialty ,Asymptomatic ,Internal medicine ,asymptomatic carotid artery stenosi ,medicine ,asymptomatic carotid artery stenosis ,business.industry ,Carotid Stenosis/complications ,Stroke/prevention & control ,Perioperative ,medicine.disease ,Surgery ,Stenosis ,Human medicine ,business - Abstract
SummaryBackgroundIf carotid artery narrowing remains asymptomatic (ie, has caused no recent stroke or other neurological symptoms), successful carotid endarterectomy (CEA) reduces stroke incidence for some years. We assessed the long-term effects of successful CEA.MethodsBetween 1993 and 2003, 3120 asymptomatic patients from 126 centres in 30 countries were allocated equally, by blinded minimised randomisation, to immediate CEA (median delay 1 month, IQR 0·3–2·5) or to indefinite deferral of any carotid procedure, and were followed up until death or for a median among survivors of 9 years (IQR 6–11). The primary outcomes were perioperative mortality and morbidity (death or stroke within 30 days) and non-perioperative stroke. Kaplan-Meier percentages and logrank p values are from intention-to-treat analyses. This study is registered, number ISRCTN26156392.Findings1560 patients were allocated immediate CEA versus 1560 allocated deferral of any carotid procedure. The proportions operated on while still asymptomatic were 89·7% versus 4·8% at 1 year (and 92·1% vs 16·5% at 5 years). Perioperative risk of stroke or death within 30 days was 3·0% (95% CI 2·4–3·9; 26 non-disabling strokes plus 34 disabling or fatal perioperative events in 1979 CEAs). Excluding perioperative events and non-stroke mortality, stroke risks (immediate vs deferred CEA) were 4·1% versus 10·0% at 5 years (gain 5·9%, 95% CI 4·0–7·8) and 10·8% versus 16·9% at 10 years (gain 6·1%, 2·7–9·4); ratio of stroke incidence rates 0·54, 95% CI 0·43–0·68, p
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- 2010
3. 159: A study of cholelithiasis during pregnancy and its relationship with age, parity, menarche, breast-feeding, dysmenorrhea, oral contraception and a maternal history of cholelithiasis
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Basso, Luigi, Mccollum, Pt, Darling, Mr, Tocchi, Adriano, and Tanner, Wa
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- 1992
4. Utility of real time ultrasound assessment of gallbladder in pregnancy
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Basso, Luigi, Mccollum, Pt, Darling, Mr, and Tanner, Wa
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- 1991
5. Statin-induced apoptosis of vascular endothelial cells is blocked by dexamethasone
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Newton, CJ, primary, Ran, G, additional, Xie, YX, additional, Bilko, D, additional, Burgoyne, CH, additional, Adams, I, additional, Abidia, A, additional, McCollum, PT, additional, and Atkin, SL, additional
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- 2002
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6. Individual Surgeon Outcomes and the Public.
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McCollum PT
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- 2017
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7. Preoperative Supervised Exercise Improves Outcomes After Elective Abdominal Aortic Aneurysm Repair: A Randomized Controlled Trial.
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Barakat HM, Shahin Y, Khan JA, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal mortality, Female, Hemorrhage, Hospitals, University, Humans, Male, Prospective Studies, Reoperation, Risk Factors, Treatment Outcome, Aortic Aneurysm, Abdominal surgery, Elective Surgical Procedures methods, Exercise, Length of Stay, Preoperative Care methods
- Abstract
Objective: The aim of the study was to assess the impact of a preoperative medically supervised exercise program on outcomes after elective abdominal aortic aneurysm (AAA) repair., Background: Functional capacity is an important predictor of postoperative outcomes after elective AAA repair. Improving patients' preoperative fitness with exercise has the potential to positively influence recovery., Methods: A randomized controlled trial was performed at a tertiary vascular unit. Patients scheduled for open or endovascular AAA repair were randomized to either 6 weeks of preoperative supervised exercise or standard treatment using sealed envelopes. The primary outcome measure was a composite endpoint of cardiac, pulmonary, and renal complications. Secondary outcome measures were 30-day mortality, lengths of hospital and critical care stay, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, reoperation, and postoperative bleeding., Results: One hundred twenty-four patients were randomized (111 men, mean [SD] age 73 [7] y). Fourteen patients sustained postoperative complications in the exercise group (22.6%), compared with 26 in the nonexercise group (41.9%; P = 0.021). Four patients (2 in each group) died within the first 30 postoperative days. Duration of hospital stay was significantly shorter in the exercise group (median 7 [interquartile range 5-9] vs 8 [interquartile range 6-12.3] d; P = 0.025). There were no significant differences between the groups in the length of critical care stay (P = 0.845), APACHE II scores (P = 0.256), incidence of reoperations (P = 1.000), or postoperative bleeding (P = 0.343)., Conclusions: A period of preoperative supervised exercise training reduces postoperative cardiac, respiratory, renal complications, and length of hospital stay in patients undergoing elective AAA repair.
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- 2016
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8. Comparison of Use of Short Form-36 Domain Scores and Patient Responses for Derivation of Preference-Based SF6D Index to Calculate Quality-Adjusted Life Years in Patients with Intermittent Claudication.
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Mazari FA, Shahin Y, Khan JA, Samuel N, Carradice D, McCollum PT, and Chetter IC
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- Aged, Databases, Factual, Female, Humans, Intermittent Claudication economics, Intermittent Claudication physiopathology, Intermittent Claudication psychology, Male, Middle Aged, Predictive Value of Tests, Quality-Adjusted Life Years, Randomized Controlled Trials as Topic, Reproducibility of Results, Retrospective Studies, Time Factors, Intermittent Claudication diagnosis, Patient Preference, Quality of Life, Surveys and Questionnaires
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Background: The short form 36 (SF36) questionnaire is used for assessment of generic quality of life. Responses to the individual question in SF36 are also used for calculation of the SF6D index score. This score is used for calculation of quality adjusted-life years (QALYs) in economical analyses. As the individual patient questionnaires are not always available for performing systematic reviews and meta-analyses, a new formula has been developed for derivation of SF6D index score from the reported SF36-domain scores. This study aimed to evaluate the validity of this formula for use in patients with intermittent claudication., Methods: A retrospective review of a prospectively collected database of a randomized controlled trial was performed. A total of 178 patients were recruited. Clinical indicators of ischemia were recorded. All patients completed SF36 questionnaires. Response and domain-based SF6D scores (R-SF6D and D-SF6D) and QALYs were calculated. Correlation and agreement analysis were performed., Results: Response rate was 88% (n = 781) over a 1-year follow-up period. Domain-based SF6D score (mean, 0.684; standard deviation [SD] 0.110) was significantly higher (paired t-test, P = 0.001) than the response-based score (mean, 0.627; SD, 0.110) with a mean difference of 0.056 (95% confidence interval, 0.053-0.060). Mean QALY calculated using D-SF6D score (0.503; SD, 0.116) was also significantly higher than the QALY calculated from the R-SF6D score (0.467; SD, 0.121). Bland-Altman comparison showed strong agreement (limit of agreement -0.167 to 0.054) between the 2 methods with equal variances (Pitman's test, P = 0.629). D-SF6D scores showed stronger correlation with clinical indicators of ischemia (r = 0.246-0.602) compared with that of R-SF6D scores (r = 0.233-0.549)., Conclusions: Domain-based estimation of SF6D score is a valid and reliable method with strong agreement to the gold standard response-based scores in claudicants. However, adjustments may be required in studies using a mixture of D-SF6D and R-SF6D scores for QALY calculation., (Copyright © 2016 Elsevier Inc. All rights reserved.)
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- 2016
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9. Prediction of organ-specific complications following abdominal aortic aneurysm repair using cardiopulmonary exercise testing.
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Barakat HM, Shahin Y, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Anaerobic Threshold, Carbon Dioxide metabolism, Critical Care, Exercise Test statistics & numerical data, Female, Heart Diseases etiology, Hospital Mortality, Humans, Length of Stay, Male, Middle Aged, Physical Fitness, Postoperative Care, Postoperative Complications mortality, Predictive Value of Tests, Prospective Studies, Risk Assessment, Vascular Surgical Procedures, Aortic Aneurysm, Abdominal surgery, Exercise Test methods, Postoperative Complications epidemiology
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This study aimed at assessing whether measures of aerobic fitness can predict postoperative cardiac and pulmonary complications, 30-day mortality and length of hospital stay following elective abdominal aortic aneurysm repair. We prospectively collected cardiopulmonary exercise testing data over two years for 130 patients. Upon multivariate analysis, a decreased anaerobic threshold (OR (95% CI) 0.55 (0.37-0.84); p = 0.005) and open repair (OR (95% CI) 6.99 (1.56-31.48); p = 0.011) were associated with cardiac complications. Similarly, an increased ventilatory equivalent for carbon dioxide (OR (95% CI) 1.18 (1.05-1.33); p = 0.005) and open repair (OR (95% CI) 14.29 (3.24-62.90); p < 0.001) were associated with pulmonary complications. Patients who had an endovascular repair had shorter hospital and critical care lengths of stay (p < 0.001). Measures of fitness were not associated with 30-day mortality or length of hospital stay. Cardiopulmonary exercise testing variables, therefore, seem to predict different postoperative complications following abdominal aortic aneurysm repair, which adds value to their routine use in risk stratification and optimisation of peri-operative care., (© 2015 The Association of Anaesthetists of Great Britain and Ireland.)
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- 2015
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10. Supervised exercise program improves aerobic fitness in patients awaiting abdominal aortic aneurysm repair.
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Barakat HM, Shahin Y, Barnes R, Gohil R, Souroullas P, Khan J, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Anaerobic Threshold, Aortic Aneurysm, Abdominal diagnosis, Aortic Aneurysm, Abdominal physiopathology, Elective Surgical Procedures, England, Exercise Test, Female, Humans, Male, Oxygen Consumption, Risk Factors, Time Factors, Treatment Outcome, Aortic Aneurysm, Abdominal surgery, Endovascular Procedures, Exercise Therapy, Physical Fitness, Vascular Surgical Procedures, Waiting Lists
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Background: Aerobic fitness is an important predictor of postoperative outcome in major surgery. In this study, we assess the effects of a period of preoperative exercise on aerobic fitness as measured by cardiopulmonary exercise testing (CPET) in patients scheduled for abdominal aortic aneurysm (AAA) repair., Methods: As part of a randomized trial, the first patients recruited in the intervention group were enrolled in a supervised exercise program of six week duration. Treadmill CPET parameters were measured before and after exercise preoperatively for these patients. These parameters were as follows: peak oxygen uptake (VO2 peak), anaerobic threshold (AT), and ventilator equivalents for oxygen and carbon dioxide (VE/VO2 and VE/VCO2, respectively). Total exercise time and the time at which AT was achieved were also recorded. A comparison between pre- and postexercise parameters was made to detect for a possible improvement in aerobic fitness., Results: Twenty patients with AAA (17 men; mean age: 74.9 ± 5.9 years) were included in this study. Thirty-five percent of patients had a history of ischemic heart disease, 25% of obstructive airway disease, and 15% of cerebral vascular events. Seventy percent were previous smokers, and 15% were current smokers. Fifty-five percent of patients were taking aspirin and 75% were undergoing statin therapy. The median (interquartile range) VO2 peak at baseline was 18.2 (15.4-19.9) mL/kg/min, and after exercise was 19.9 (17.1-21.1; P = 0.048). Median AT at baseline was 12.2 (10.5-14.9), and 14.4 (12.3-15.4) after exercise (P = 0.023). Time of exercise tolerated also improved from a median of 379 to 604 sec (P = 0.001). No significant changes were seen in VE/VO2, VE/VCO2, or the time at which AT was achieved., Conclusion: This study shows that cardiopulmonary aerobic fitness improves after a period of supervised exercise in patients scheduled for AAA repair. This is justification for a randomized trial to assess whether this affects morbidity and mortality after AAA repair., (Copyright © 2014 Elsevier Inc. All rights reserved.)
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- 2014
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11. Economic analysis of a randomized trial of percutaneous angioplasty, supervised exercise or combined treatment for intermittent claudication due to femoropopliteal arterial disease.
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Mazari FA, Khan JA, Carradice D, Samuel N, Gohil R, McCollum PT, and Chetter IC
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- Analysis of Variance, Combined Modality Therapy economics, Cost-Benefit Analysis, Femoral Artery, Humans, Intermittent Claudication therapy, Popliteal Artery, Quality of Life, Quality-Adjusted Life Years, Treatment Outcome, Angioplasty economics, Exercise Therapy economics, Intermittent Claudication economics
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Background: The aim was to compare costs and utilities of percutaneous transluminal angioplasty (PTA), a supervised exercise programme (SEP) and combined treatment (PTA + SEP) in patients with intermittent claudication (IC) to establish the most cost-effective treatment., Methods: Patients with IC due to femoropopliteal disease were randomized to receive PTA, SEP or PTA + SEP. Assessments were performed before, and at 1, 3, 6 and 12 months postintervention. Clinical and quality-of-life indicators were recorded. The SF-6D Health Utilities index was calculated from the Short Form 36, plotted, and quality-adjusted life-years (QALYs) were generated by calculating the area under the curve. Costs were calculated using National Health Service 2009-2010 payment-by-results tariffs and the National Institute for Health Research Clinical Research Network Investigation pricing index, and adjusted for reinterventions. Cost per QALY and incremental costs were calculated, and sensitivity analyses performed., Results: A total of 178 patients (PTA, 60; SEP, 60; PTA + SEP, 58) were randomized. All treatments resulted in significant improvement in the SF-6D index (P < 0.001). There was no significant difference between treatments in mean QALYs gained (PTA: 0.620, 95 per cent confidence interval 0.588 to 0.652; SEP: 0.629, 0.597 to 0.660; PTA + SEP: 0.649, 0.622 to 0.675). The adjusted mean cost per procedure was significantly higher for PTA (€7301.74) compared with SEP (€3866.49) and PTA + SEP (€6911.68) (P < 0.001). The cost per QALY was significantly higher for PTA (€11,777.00) compared with SEP (€6147.04) and PTA + SEP (€10,649.74). QALYs were lost when PTA alone was used as first-line treatment in comparison with SEP or PTA + SEP. These results were robust and valid in sensitivity analyses., Conclusion: Supervised exercise is the most cost-effective first-line treatment for IC, and when combined with PTA is more cost-effective than PTA alone., (© 2013 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2013
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12. Role of pre-operative multiple gated acquisition scanning in predicting long-term outcome in patients undergoing elective abdominal aortic aneurysm repair.
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Barakat HM, Shahin Y, Khan JA, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal diagnostic imaging, Aortic Aneurysm, Abdominal mortality, Aortic Aneurysm, Abdominal physiopathology, Electrocardiography, Female, Follow-Up Studies, Humans, Male, Middle Aged, Preoperative Period, Radionuclide Imaging, Retrospective Studies, Survival Analysis, Treatment Outcome, Aortic Aneurysm, Abdominal surgery, Elective Surgical Procedures, Preoperative Care, Radiopharmaceuticals, Stroke Volume, Technetium
- Abstract
Objective: To determine whether resting pre-operative left ventricular ejection fraction (LVEF) estimated by multiple gated acquisition scanning (MUGA) predicts long-term survival in patients undergoing elective abdominal aortic aneurysm (AAA) repair., Methods: A retrospective study of MUGA scans which were performed to estimate pre-operative resting LVEF in 127 patients [106 (83 %) males, mean age 74 ± 7.6 years] who underwent elective AAA repair over a period of 4 years from March 2007. We compared outcomes and long-term survival between patients who had a pre-operative LVEF ≤ 40 % (Group 1, n = 60) and LVEF > 40 % (Group 2, n = 67)., Results: Overall 19 (15 %) patients died during the follow-up period (13 patients in group 1 and 6 patients in group 2). 30-day mortality was 8 %. There was no significant difference between group 1 and 2 in terms of patients' mean age or median length of hospital stay (8 days for both groups, p = 0.61). However, group 2 had more females than group 1(18 vs. 3, p = 0.001). Median survival for patients in group 2 was significantly higher than patients in group 1 (1,258 days vs. 1,000 days, p = 0.03). In a Cox regression model which included age, sex, smoking status and LVEF as covariates, only smoking status and LVEF predicted survival [Hazard ratio (HR) = 1.06, p = 0.04 and HR = 0.93, p = 0.00, respectively]., Conclusion: This study shows that there is a role for pre-operative MUGA scan assessment of resting LVEF in predicting long-term survival post elective AAA repair and that the lower the pre-operative LVEF the poorer the long-term outcome.
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- 2013
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13. Intraluminal thrombus has a selective influence on matrix metalloproteinases and their inhibitors (tissue inhibitors of matrix metalloproteinases) in the wall of abdominal aortic aneurysms.
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Khan JA, Abdul Rahman MN, Mazari FA, Shahin Y, Smith G, Madden L, Fagan MJ, Greenman J, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Aorta, Abdominal diagnostic imaging, Aortic Aneurysm, Abdominal diagnostic imaging, Aortography methods, England, Enzyme-Linked Immunosorbent Assay, Female, Humans, Male, Matrix Metalloproteinase 2 analysis, Matrix Metalloproteinase 8 analysis, Matrix Metalloproteinase 9 analysis, Middle Aged, Regression Analysis, Thrombosis diagnostic imaging, Tissue Inhibitor of Metalloproteinase-1 analysis, Tissue Inhibitor of Metalloproteinase-2 analysis, Tomography, X-Ray Computed, Aorta, Abdominal enzymology, Aortic Aneurysm, Abdominal enzymology, Matrix Metalloproteinases analysis, Thrombosis enzymology, Tissue Inhibitor of Metalloproteinases analysis
- Abstract
Background: The influence of intraluminal thrombus (ILT) on the proteolytic environment within the wall of an abdominal aortic aneurysm (AAA) is unknown. This is the first study to examine the correlation between ILT thickness and the levels of matrix metalloproteinases (MMPs) and their natural inhibitors (tissue inhibitors of matrix metalloproteinases [TIMPs]) within the adjacent AAA wall., Methods: Thirty-five patients undergoing elective repair of AAAs were studied. A single full-thickness infrarenal aortic sample was obtained uniformly from the arteriotomy site from each patient. All samples were snap frozen and analyzed for total and active MMP 2, 8, and 9 and TIMP 1 and 2. Thrombus thickness at the specimen site was measured on the preoperative contrast computed tomographic angiograms., Results: There was a statistically significant correlation between ILT thickness, concentration of TIMP 1, and active concentration of MMP 9. MMP 2 (active and total) and TIMP 2 demonstrated a positive correlation with ILT thickness, although not statistically significant., Conclusion: In this novel study, we found a significant positive correlation of ILT thickness with active MMP 9 and TIMP 1 concentration in the adjacent AAA wall, and this may have implications for AAA expansion and eventual rupture., (Copyright © 2012 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)
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- 2012
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14. Randomized clinical trial of percutaneous transluminal angioplasty, supervised exercise and combined treatment for intermittent claudication due to femoropopliteal arterial disease.
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Mazari FA, Khan JA, Carradice D, Samuel N, Abdul Rahman MN, Gulati S, Lee HL, Mehta TA, McCollum PT, and Chetter IC
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- Aged, Angiography, Arterial Occlusive Diseases complications, Arterial Occlusive Diseases therapy, Combined Modality Therapy, Female, Humans, Intermittent Claudication etiology, Male, Middle Aged, Prospective Studies, Quality of Life, Recurrence, Retreatment, Risk Factors, Treatment Outcome, Angioplasty, Balloon, Exercise, Exercise Therapy, Femoral Artery pathology, Intermittent Claudication therapy, Popliteal Artery pathology
- Abstract
Background: The aim was to compare percutaneous transluminal angioplasty (PTA), a supervised exercise programme (SEP) and combined treatment (PTA plus SEP) for intermittent claudication due to femoropopliteal arterial disease., Methods: Consenting patients with femoropopliteal arterial lesions were randomized to one of three treatment arms: PTA, SEP, or PTA plus SEP. All patients received optimal medical treatment. Patients were assessed at baseline and 1, 3, 6 and 12 months after intervention. Clinical (ankle pressures, walking distances, symptoms) and quality-of-life (QoL) outcomes (Short Form 36, VascuQol) were analysed., Results: A total of 178 patients (108 men, median age 70 years) were included. All three treatment groups demonstrated significant clinical and QoL improvements. One year after PTA (60 patients, 8 withdrew), 37 patients (71 per cent) had improved (16 mild, 16 moderate, 5 marked), nine (17 per cent) showed no improvement and six (12 per cent) had deteriorated. After SEP (60 patients, 14 withdrew), 32 patients (70 per cent) had improved (19 mild, 10 moderate, 3 marked), six (13 per cent) showed no improvement and eight (17 per cent) had deteriorated. After PTA plus SEP (58 patients, 11 withdrew), 40 patients (85 per cent) had improved (18 mild, 20 moderate, 2 marked), seven (15 per cent) showed no improvement and none had deteriorated. On intergroup analysis, PTA and SEP alone were equally effective in improving clinical outcomes, although the effect was short-lived. PTA plus SEP produced a more sustained clinical improvement, but there was no significant QoL advantage., Conclusion: For patients with intermittent claudication due to femoropopliteal disease, PTA, SEP, and PTA plus SEP were all equally effective in improving walking distance and QoL after 12 months., Registration Number: NCT00798850 (http://www.clinicaltrials.gov)., (Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2012
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15. Patients' perspective of functional outcome after elective abdominal aortic aneurysm repair: a questionnaire survey.
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Khan JA, Mazari FA, Abdul Rahman MN, Mockford K, Chetter IC, and McCollum PT
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- Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal physiopathology, Aortic Aneurysm, Abdominal psychology, Awareness, Comprehension, Elective Surgical Procedures, Female, Health Care Surveys, Humans, Male, Patient Education as Topic, Patient Satisfaction, Prospective Studies, Recovery of Function, Surveys and Questionnaires, Time Factors, Treatment Outcome, United Kingdom, Aortic Aneurysm, Abdominal surgery, Blood Vessel Prosthesis Implantation psychology, Endovascular Procedures psychology, Health Knowledge, Attitudes, Practice, Patients psychology
- Abstract
Background: To evaluate patients' awareness, functional outcome, and satisfaction after abdominal aortic aneurysm (AAA) repair., Methods: A study-specific questionnaire was developed with collaboration of a multidisciplinary team. Lists of patients who underwent elective open AAA repair and endovascular aneurysm repair (EVAR) between January 2006 and December 2008 were obtained from the departmental database and cross-checked against hospital database for survival status. Emergency AAA repairs were excluded. Study questionnaires were posted to 138 patients (113 open, 25 EVAR) with self-addressed stamped return envelopes. Statistical analysis was performed using SPSS v16.0., Results: Response rate was 89% (n = 123; 102 open, 21 EVAR). Seventy-one percent (n = 88) were unaware of this condition before diagnosis. Ninety-seven percent (n = 120) indicated their understanding of the need for surgery. Ninety-two percent (n = 113) stated that the operation was adequately explained to them. Ninety percent (n = 111) reported full recovery after surgery, with 60% (n = 74) recovering within 6 months. Eighty-seven percent (n = 108) were satisfied with the overall experience, and 85% (n = 105) stated that they would recommend the operation to family and/or friends if required., Conclusions: There is a lack of awareness regarding AAA in elderly population. However, after being diagnosed, patients understand the implications and are satisfied with the overall results and would recommend AAA repair to family and/or friends if required., (Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)
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- 2011
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16. Randomized phase II clinical trial of avotermin versus placebo for scar improvement.
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McCollum PT, Bush JA, James G, Mason T, O'Kane S, McCollum C, Krievins D, Shiralkar S, and Ferguson MW
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- Adult, Aged, Aged, 80 and over, Double-Blind Method, Female, Humans, Injections, Intradermal, Male, Middle Aged, Prospective Studies, Surgicenters, Treatment Outcome, Varicose Veins surgery, Young Adult, Cicatrix drug therapy, Dermatologic Agents administration & dosage, Groin surgery, Transforming Growth Factor beta3 administration & dosage
- Abstract
Background: Scarring is a major problem following skin injury. In early clinical trials, transforming growth factor β3 (avotermin) improved scar appearance. The aim of this study was to determine whether an injection of avotermin at the time of wound closure is effective in improving scar appearance., Methods: Study RN1001-0042, a double-blind, randomized, within-patient, placebo-controlled trial, investigated the efficacy and safety of four doses of avotermin given once. Patients undergoing bilateral surgery to remove varicose leg veins by saphenofemoral ligation and long saphenous vein stripping were enrolled at 20 European centres. A total of 156 patients were randomized to receive one of four doses of avotermin (5, 50, 200 or 500 ng per 100 µl, at 100 µl per linear cm of wound margin), administered by intradermal injection to the groin and distal wound margins of one leg; placebo was administered to the other leg. Scar appearance was evaluated by an independent panel of lay people (lay panel), investigators and patients. The primary efficacy variable was lay panel Total Scar Score (ToScar), derived from visual analogue scale scores for groin scars between 6 weeks and 7 months., Results: Avotermin 500 ng significantly improved groin scar appearance compared with placebo (mean lay panel ToScar difference 16·49 mm; P = 0·036)., Conclusion: Avotermin 500 ng per 100 µl per linear cm of wound margin given once is well tolerated and significantly improves scar appearance., (Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2011
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17. A randomized placebo controlled trial of the effect of preoperative statin use on matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in areas of low and peak wall stress in patients undergoing elective open repair of abdominal aortic aneurysm.
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Rahman MN, Khan JA, Mazari FA, Mockford K, McCollum PT, and Chetter IC
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- Aged, Aged, 80 and over, Aorta, Abdominal enzymology, Aorta, Abdominal pathology, Aorta, Abdominal surgery, Aortic Aneurysm, Abdominal enzymology, Aortic Aneurysm, Abdominal pathology, Aortic Aneurysm, Abdominal surgery, Atorvastatin, Chi-Square Distribution, Double-Blind Method, Drug Administration Schedule, Elective Surgical Procedures, England, Female, Finite Element Analysis, Humans, Male, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 8 metabolism, Matrix Metalloproteinase 9 metabolism, Middle Aged, Placebo Effect, Preoperative Care, Stress, Mechanical, Time Factors, Tissue Inhibitor of Metalloproteinase-1 metabolism, Tissue Inhibitor of Metalloproteinase-2 metabolism, Treatment Outcome, Aorta, Abdominal drug effects, Aortic Aneurysm, Abdominal drug therapy, Heptanoic Acids administration & dosage, Hydroxymethylglutaryl-CoA Reductase Inhibitors administration & dosage, Matrix Metalloproteinases metabolism, Pyrroles administration & dosage, Tissue Inhibitor of Metalloproteinases metabolism, Vascular Surgical Procedures
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Background: A double-blind, randomized controlled trial was carried out to study the effects of statins on matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in areas of peak and low abdominal aortic aneurysm (AAA) wall stress., Methods: A total of 40 patients undergoing elective open AAA repair were randomized to receive either atorvastatin 80 mg (n = 20) or placebo (n = 20) for 4 weeks preoperatively. Finite element analysis was used to determine AAA wall stress distribution. Full thickness aortic samples were obtained at surgery from areas of low and peak wall stress, snap-frozen, and stored at -80°C for subsequent MMP-2, -8, and -9 and TIMP-1 and -2 analyses. Statistical analysis was performed using SPSS 16.0 (SPSS Inc, Chicago, IL)., Results: Both groups were well matched (p > 0.05) regarding age, gender, comorbidities, and duration of hospital stay. There were no statistically significant differences in levels of MMPs and TIMPs between the statin and placebo group and between areas of low and peak AAA wall stress., Conclusion: The short-term use of statins is not associated in reducing levels of MMP 2, 8, and 9 and TIMP-1 and -2 in areas of low and peak wall stress in patients with AAA., (Copyright © 2011. Published by Elsevier Inc.)
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- 2011
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18. An analysis of relationship between quality of life indices and clinical improvement following intervention in patients with intermittent claudication due to femoropopliteal disease.
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Mazari FA, Carradice D, Rahman MN, Khan JA, Mockford K, Mehta T, McCollum PT, and Chetter IC
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- Aged, Ankle Brachial Index, Arterial Occlusive Diseases complications, Arterial Occlusive Diseases physiopathology, Arterial Occlusive Diseases psychology, England, Exercise Test, Exercise Tolerance, Female, Hospitals, University, Humans, Intermittent Claudication etiology, Intermittent Claudication physiopathology, Intermittent Claudication psychology, Male, Middle Aged, Predictive Value of Tests, Prospective Studies, Statistics, Nonparametric, Surveys and Questionnaires, Time Factors, Treatment Outcome, Angioplasty, Arterial Occlusive Diseases therapy, Exercise Therapy, Femoral Artery, Intermittent Claudication therapy, Popliteal Artery, Quality of Life
- Abstract
Objectives: To establish the relationship between quality of life (QOL) index scores and clinical indicators of lower limb ischemia., Methods: One hundred seventy-eight patients (108 men, median age 70 years) with femoropopliteal lesions suitable for angioplasty were recruited. Assessments were performed prior to and at 1, 3, 6, and 12 months following intervention (angioplasty and/or supervised exercise program). Clinical indicators of lower limb ischemia (treadmill walking distances, ankle pressures), generic (SF36, EuroQol), and disease-specific (Kings College VascuQol) quality of life questionnaires were analyzed. Correlation analysis was performed for index scores (SF-6D, EQ-5D, VascuQol) and individual domain scores using nonparametric tests., Results: All clinical indicators of lower limb ischemia and quality of life index scores showed a statistically significant improvement as result of intervention (Friedman test, P < .001). Both generic QOL index scores (SF-6D, EQ-5D) showed moderate but statistically significant correlation (Spearman's rank correlation, P < .001) with treadmill walking distances (SF-6D r = 0.533, EQ-5D r = 0.500) and weak but significant correlation to resting and postexercise ankle-brachial pressure index (SF-6D r = 0.253, EuroQol r = 0.214). Disease-specific index scores (VascuQol) showed similar moderate correlation to treadmill walking distances (r = 0.584, P < .001) and weak but statistically significant correlation with resting and postexercise ABPI (r = 0.377, P < .001). All index scores showed strong and statistically significant (P< .001) correlation with patient-reported walking distance (SF-6D r = 0.604, EQ-5D r = 0.511, VascuQol r = 0.769). All domains of SF36 showed similar correlation with clinical indicators except general health. The strongest correlation was seen with treadmill walking distances in the domains of physical function (r = 0.538) and bodily pain (r = 0.524)., Conclusion: All generic and disease-specific QOL scores show statistically significant improvement with angioplasty and/or supervised exercise in patients with claudication due to femoropopliteal atherosclerosis. However, the degree of improvement seen in clinical indicators of lower limb ischemia is not reflected in these scores. These findings support the use of composite outcome measures with mandatory, independent assessment of QOL as an independent outcome measure in intervention studies in these patients., (Copyright (c) 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)
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- 2010
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19. Obstacles in initiating a new research project--reflection on medical research in UK.
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Khan JA, Mazari FA, Chetter IC, and McCollum PT
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- Ethics Committees, Research, Humans, Patient Selection, Time Factors, United Kingdom, Biomedical Research organization & administration
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- 2010
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20. Early outcomes from a randomized, controlled trial of supervised exercise, angioplasty, and combined therapy in intermittent claudication.
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Mazari FA, Gulati S, Rahman MN, Lee HL, Mehta TA, McCollum PT, and Chetter IC
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- Aged, Ankle blood supply, Arterial Occlusive Diseases complications, Arterial Occlusive Diseases physiopathology, Arterial Occlusive Diseases psychology, Blood Pressure, Combined Modality Therapy, Exercise Test, Exercise Tolerance, Female, Humans, Intermittent Claudication etiology, Intermittent Claudication physiopathology, Intermittent Claudication psychology, Male, Middle Aged, Prospective Studies, Quality of Life, Recovery of Function, Surveys and Questionnaires, Time Factors, Treatment Outcome, Walking, Angioplasty, Balloon, Arterial Occlusive Diseases therapy, Exercise Therapy, Femoral Artery physiopathology, Intermittent Claudication therapy, Popliteal Artery physiopathology
- Abstract
Background: To compare angioplasty (PTA), supervised exercise (SEP) and PTA + SEP in the treatment of intermittent claudication (IC) due to femoropopliteal disease., Methods: Over a 6-year period, 178 patients (108 men; median age, 70 years) with femoropopliteal lesions suitable for angioplasty were randomized to PTA, SEP, or PTA + SEP. Patients were assessed prior to and at 1 and 3 months post treatment. ISCVS outcome criteria (ankle pressures, treadmill walking distances) and quality of life (QoL) questionnaires (SF-36 and VascuQoL) were analyzed., Results: All groups were well matched at baseline. Twenty-one patients withdrew. Results are as follows: Intragroup analysis: All groups demonstrated significant clinical and QoL improvements (Friedman test, p < 0.05). SEP (60 patients, 8 withdrew)-62.7% of patients (n = 32) improved following treatment [20 mild, 9 moderate, 3 marked], 27.4% (n = 14) demonstrated no improvement, and 9.8% (n = 5) deteriorated. PTA (60 patients, 3 withdrew)-66.6% patients (n = 38) improved following treatment [19 mild, 10 moderate, 9 marked], 22.8% (n = 13) demonstrated no improvement, and 10.5% (n = 6) deteriorated. PTA + SEP (58 patients, 10 withdrew)-81.6% of patients (n = 40) improved following treatment [10 mild, 17 moderate, 3 marked], 14.2% (n = 7) demonstrated no improvement, and 4.0% (n = 2) deteriorated. Intergroup analysis: PTA + SEP produce a much greater improvement in clinical outcome measures than PTA or SEP alone, but there was no significant QoL advantage (Kruskal-Wallis test, p > 0.05)., Conclusion: SEP should be the primary treatment for the patients with claudication and PTA should be supplemented by an SEP., (Copyright 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)
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- 2010
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21. Randomized clinical trial of co-amoxiclav versus no antibiotic prophylaxis in varicose vein surgery.
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Mekako AI, Chetter IC, Coughlin PA, Hatfield J, and McCollum PT
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- Adult, Asepsis methods, Double-Blind Method, Female, Humans, Male, Middle Aged, Treatment Outcome, Amoxicillin-Potassium Clavulanate Combination therapeutic use, Anti-Bacterial Agents therapeutic use, Antibiotic Prophylaxis methods, Surgical Wound Infection prevention & control, Varicose Veins surgery
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Background: Wound infection rates of up to 16 per cent are reported following varicose vein surgery and the value of antibiotic prophylaxis in clean surgery remains unclear., Methods: Some 443 patients undergoing varicose vein surgery randomly received a single prophylactic dose of 1.2 g co-amoxiclav (219 patients) or no antibiotic (224). Patients completed a wound diary on postoperative days 3, 5, 7, 9 and 10 using an adapted ASEPSIS method of wound assessment, and were reviewed after 14 days., Results: Patients who had prophylaxis had lower ASEPSIS wound scores on days 3, 5 and 7 (P = 0.043, P = 0.032 and P = 0.003 respectively), and lower total ASEPSIS scores (median (interquartile range) 3 (0-9) versus 6 (0-15); P = 0.013). They were less likely to consult their general practitioner (16.0 versus 24.3 per cent; P = 0.040) or to receive postoperative antibiotics (4.7 versus 13.5 per cent; P = 0.002) for wound-related problems. Wound outcomes were worse with higher body mass index (odds ratio (OR) 0.92 (95 per cent confidence interval (c.i.) 0.87 to 0.97); P = 0.005) and current smoking (OR 0.5 (0.3 to 0.9); P = 0.033). Prophylactic antibiotics conferred satisfactory wound healing (OR 2.2 (95 per cent c.i. 1.3 to 3.6); P = 0.003)., Conclusion: Antibiotic prophylaxis reduced wound-related problems after varicose vein surgery. Registration number ISRCTN12467340 (http://www.controlled-trials.com)., (Copyright 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2010
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22. Peak wall stress measurement in elective and acute abdominal aortic aneurysms.
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Heng MS, Fagan MJ, Collier JW, Desai G, McCollum PT, and Chetter IC
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- Acute Disease, Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal complications, Aortic Aneurysm, Abdominal diagnostic imaging, Aortic Aneurysm, Abdominal surgery, Aortic Rupture diagnostic imaging, Aortography methods, Cohort Studies, Elective Surgical Procedures, Emergency Medical Services, Female, Humans, Imaging, Three-Dimensional, Male, Middle Aged, Observer Variation, Patient Selection, Prospective Studies, Radiographic Image Interpretation, Computer-Assisted, Reproducibility of Results, Retrospective Studies, Risk Assessment, Risk Factors, Stress, Mechanical, Tomography, X-Ray Computed, Aortic Aneurysm, Abdominal pathology, Aortic Rupture etiology, Aortic Rupture pathology, Finite Element Analysis, Models, Cardiovascular, Vascular Surgical Procedures
- Abstract
Background: Abdominal aortic aneurysm (AAA) rupture occurs when wall stress exceeds wall strength. Engineering principles suggest that aneurysm diameter is only one aspect of its geometry that influences wall stress. Finite element analysis considers the complete geometry and determines wall stresses throughout the structure. This article investigates the interoperator and intraoperator reliability of finite element analysis in the calculation of peak wall stress (PWS) in AAA and examines the variation in PWS in elective and acute AAAs., Method: Full ethics and institutional approval was obtained. The study recruited 70 patients (30 acute, 40 elective) with an infrarenal AAA. Computed tomography (CT) images were obtained of the AAA from the renal vessels to the aortic bifurcation. Manual edge extraction, three-dimensional reconstruction, and blinded finite element analysis were performed to ascertain location and value of PWS. Ten CT data sets were analyzed by four different operators to ascertain interoperator reliability and by one operator twice to ascertain intraoperator reliability. An intraclass correlation coefficient was obtained. The Mann-Whitney U test and independent samples t test compared groups for statistical significance., Results: The intraclass correlation coefficient was 0.71 for interoperator reliability and 0.84 for intraoperator reliability. There was no statistically significant difference in the mean (SD) maximal AAA diameter between elective (6.47 [1.30] cm) and acute (7.08 [1.39] cm) patients (P = .073). The difference in PWS between elective (0.67 [0.30] MPa) and acute (1.11 [0.51] MPa) patients (P = .008) was statistically significant, however., Conclusion: Interoperator and intraoperator reliability in the derivation of PWS is acceptable. PWS, but not maximal diameter, was significantly higher in acute AAAs than in elective AAAs.
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- 2008
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23. Plasma tissue factor is a predictor for restenosis after femoropopliteal angioplasty.
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Ray B, Chetter IC, Lee HL, Ettelaie C, and McCollum PT
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- Aged, Aged, 80 and over, Case-Control Studies, Female, Humans, Intermittent Claudication blood, Male, Middle Aged, Prospective Studies, Secondary Prevention, Treatment Outcome, Angioplasty, Balloon, Femoral Artery, Intermittent Claudication therapy, Popliteal Artery, Thromboplastin metabolism
- Abstract
Background: In vitro studies suggest an association between raised levels of tissue factor and restenosis after coronary percutaneous transluminal angioplasty (PTA). This prospective, controlled study examined the association between plasma tissue factor concentrations and restenosis after femoropopliteal PTA., Methods: Plasma samples from ten healthy controls and 36 patients with unilateral claudication undergoing femoropopliteal PTA were collected at baseline and, in the patients with claudication, at 24 h and 1, 3 and 6 months after PTA. Clinical assessment and arterial duplex imaging were performed before and at the same time points after PTA to identify restenosis. Plasma tissue factor was measured using a specific enzyme-linked immunosorbent assay., Results: Baseline plasma tissue factor concentrations were significantly higher in patients with claudication (median 3.4 (interquartile range (i.q.r.) 1.3-7.4) ng/ml) than in controls (median 1.2 (i.q.r. 0.5-1.8) ng/ml) (P < 0.050). Baseline tissue factor concentrations were significantly higher in the ten patients with claudication who developed restenosis after PTA (median 7.0 (i.q.r. 3.4-183.5) ng/ml) than in those who did not (median 1.7 (i.q.r. 1.3-7.2) ng/ml) (P < 0.050). In addition, plasma tissue factor levels increased significantly over time in the patients who developed restenosis after PTA., Conclusion: High baseline and progressive increases in the plasma tissue factor concentration were useful predictors of restenosis after femoropopliteal angioplasty., (Copyright (c) 2007 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)
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- 2007
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24. Differential functions of tissue factor in the trans-activation of cellular signalling pathways.
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Ettelaie C, Li C, Collier ME, Pradier A, Frentzou GA, Wood CG, Chetter IC, McCollum PT, Bruckdorfer KR, and James NJ
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- Cells, Cultured, Cyclic AMP Response Element-Binding Protein metabolism, Drug Synergism, Endothelial Cells cytology, Endothelium, Vascular cytology, Factor VIIa metabolism, Factor VIIa pharmacology, Factor Xa metabolism, Factor Xa pharmacology, Flow Cytometry, Humans, JNK Mitogen-Activated Protein Kinases metabolism, Lipoproteins metabolism, Lipoproteins pharmacology, Luciferases genetics, MAP Kinase Signaling System drug effects, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, NF-kappa B metabolism, Thromboplastin genetics, Thromboplastin pharmacology, Transcription Factor AP-1 metabolism, Transfection, Umbilical Veins cytology, Endothelial Cells metabolism, MAP Kinase Signaling System physiology, Thromboplastin metabolism
- Abstract
In this study we examined the ability of tissue factor (TF) alone, or in conjunction with factor VIIa, factor Xa and TFPI in activating a number of key signalling pathways associated with cellular growth, stress and differentiation responses in human endothelial cells. We used luciferase reporter systems to demonstrate the activation of p42/44 MAPK by the TF-FVIIa complex, mediated via the PAR1 receptor. TF alone was capable of interacting with the cell surface and was sufficient to activate the JNK-SAPK pathway and subsequently AP-1, but the level of activation was enhanced by the activity of FXa on PAR1 and 2. Furthermore, the phosphorylated form of the transmembrane-cytoplasmic domain of TF was directly responsible for activation of these pathways. CREB activation occurred in response to TF-FVIIa in a non-protease dependent manner but was lowered on addition of FXa. Finally, NFkappaB activation occurred in response to FVIIa or FXa, with the latter exhibiting higher levels of activation. In conclusion, we have shown that TF is capable of activating differing signalling pathways, via more than one mechanism. The differential influence of TF is modified depending on the presence of other coagulation factors and ultimately acts as a deciding factor in the determination of cellular fate.
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- 2007
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25. A non-randomised controlled trial of the clinical and cost effectiveness of a Supervised Exercise Programme for claudication.
- Author
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Lee HL, Mehta T, Ray B, Heng MS, McCollum PT, and Chetter IC
- Subjects
- Aged, Cost-Benefit Analysis, Female, Follow-Up Studies, Humans, Male, Middle Aged, Quality of Life, Treatment Outcome, Exercise Therapy economics, Exercise Therapy methods, Intermittent Claudication economics, Intermittent Claudication physiopathology, Intermittent Claudication therapy, Walking physiology
- Abstract
Objectives: The main aims of treatment in patients with intermittent claudication (IC) are to improve the clinical indicators of lower limb ischaemia and patients' quality of life (QoL). The aims of this study were assess the clinical and cost effectiveness of a supervised exercise programme (SEP) in patients with IC., Design: Non-randomised, controlled trial., Setting: University teaching hospital., Patients and Methods: Two groups of patients with IC were studied. Seventy patients were sequentially recruited before and after the establishment of a Supervised Exercise Programme at our unit. Thirty-seven patients (median age 69 years, 26 men) received conservative medical therapy (CMT) and 33 patients (median age 67 years, 22 men) received CMT plus a 3 month SEP of graduated physical exercise for sixty minutes, three times each week. Patients were assessed prior to and at 6 months following treatment. At each assessment patient reported walking distances (PRWD), treadmill claudication and maximal distances (ICD and MWD), ankle brachial pressure indices (ABPI) pre & post exercise and patient reported QoL using the SF36 questionnaire were assessed., Results: Prior to intervention the two groups were well matched. Following treatment, CMT patients demonstrated no significant change in PRWD or ICD but did record a small but significant improvement in MWD. CMT was also associated with a negative effect size in the SF36 index and in 7 of the 8 SF36 QoL domains, effect size >-0.5 for the domains of Physical Function and Emotional Role. SEP patients demonstrated significant improvement in PRWD, ICD and MWD. SEP was associated with a positive effect size in the SF36 index and in 2 SF36 QoL domains but a negative effect size in a further 2 domains. However, all QoL effect sizes following SEP were < +/-0.5. Intergroup differences in effect sizes were >0.5 for the SF36 domains of Physical Function, Physical Role, Emotion Role and SF36 index. SEP resulted in a 0.027 quality adjusted life year (QALY) gain over CMT in the first year post-treatment thus the cost/QALY gained of SEP is pound1780 at 1 year., Conclusions: Compared to CMT, SEP increases walking distances, improves QoL and is a highly cost-effective treatment for IC.
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- 2007
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26. A nonrandomised controlled trial of endovenous laser therapy and surgery in the treatment of varicose veins.
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Mekako AI, Hatfield J, Bryce J, Lee D, McCollum PT, and Chetter I
- Subjects
- Activities of Daily Living psychology, Adult, Female, Follow-Up Studies, Humans, Male, Middle Aged, Outcome and Process Assessment, Health Care, Pilot Projects, Quality of Life psychology, Surveys and Questionnaires, Varicose Veins psychology, Angioplasty, Laser, Varicose Veins surgery
- Abstract
Endovenous laser therapy (EVLT) is a minimally invasive treatment for varicose veins. This study compares early quality-of-life (QoL) outcomes following EVLT and surgery. Two nonrandomized groups were studied: an EVLT group with 70 patients, median age 49 (interquartile range [IQR] 35-58) years, and a surgery group with 62 patients, median age 49 (IQR 35-61) years. Patients were assessed prior to and at 1, 6, and 12 weeks following the procedure using the Short Form 36 (SF-36), the Aberdeen Varicose Veins Questionnaire (AVVQ), and the Venous Clinical Severity Score (VCSS). Follow-up at 1, 6, and 12 weeks was 100%, 77%, and 70% following EVLT and 100%, 85%, and 47% following surgery. SF-36 scores were significantly better in the EVLT group at 1 week (Physical Functioning, Role Physical, Bodily Pain, Vitality, and Social Functioning domains) and at 6 weeks (Physical Functioning and Role Physical). At 12 weeks, no significant differences were evident between the groups. AVVQ scores were significantly better in the EVLT group at 6 and 12 weeks. VCSS scores were significantly improved in both groups at 12 weeks. EVLT and surgery provide similar QoL improvements in patients with varicose veins. EVLT, however, removes the QoL limitations experienced by patients in the early postoperative period.
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- 2006
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27. Pretreatment with hyperbaric oxygen and its effect on neuropsychometric dysfunction and systemic inflammatory response after cardiopulmonary bypass: a prospective randomized double-blind trial.
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Alex J, Laden G, Cale AR, Bennett S, Flowers K, Madden L, Gardiner E, McCollum PT, and Griffin SC
- Subjects
- Aged, Brain Diseases etiology, Double-Blind Method, Female, Humans, Inflammation etiology, Male, Neuropsychological Tests, Preoperative Care, Prospective Studies, Brain Diseases prevention & control, Cardiopulmonary Bypass adverse effects, Hyperbaric Oxygenation, Inflammation prevention & control
- Abstract
Objective: Animal studies have shown that pretreatment with hyperbaric oxygen can induce central nervous system ischemic tolerance and also modulate the inflammatory response. We evaluated this therapy in patients undergoing cardiopulmonary bypass., Methods: Sixty-four patients were prospectively randomized to group A (n = 31; atmospheric air, 1.5 atmospheres absolute) or group B (n = 33; hyperbaric oxygen, 2.4 atmospheres absolute) before on-pump coronary artery bypass grafting. Age, sex, body mass index, diabetes, hypertension, smoking, coronary disease severity, left ventricular function, Parsonnet score, Euroscore, bypass time, myocardial ischemia time, and number of grafts were comparable in both groups. Canadian Cardiovascular Society angina, New York Heart Association dyspnea, and previous myocardial infarction were significantly higher in group B. Inflammatory markers were analyzed before surgery and 2 and 24 hours after bypass. Neuropsychometric testing was performed 48 hours before surgery and 4 months after surgery and included trail making A and B, the Rey auditory verbal learning test, grooved peg board, information processing table A, and digit span forward and backward. Neuropsychometric dysfunction was defined as more than 1 SD deterioration in more than 2 neuropsychometric tests. Chi-square tests, Fisher tests, t tests, and analysis of variance were used as appropriate for statistical analysis., Results: Group A had a significant postoperative increase in the inflammatory markers soluble E-selectin, CD18, and heat shock protein 70. This was not observed in group B. Neuropsychometric dysfunction was also significantly higher in group A compared with group B. There was no difference in any other early postoperative clinical outcome., Conclusions: Our results seem to indicate that pretreatment with hyperbaric oxygen can reduce neuropsychometric dysfunction and also modulate the inflammatory response after cardiopulmonary bypass. However, further multicenter randomized trials are needed to clinically evaluate this form of therapy.
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- 2005
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28. Notice of inadvertent duplicate publication: statin-induced apoptosis of vascular endothelial cells is blocked by dexamethasone.
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Newton CJ, Ran G, Xie YX, Bilko D, Burgoyne CH, Adams I, Abidia A, McCollum PT, and Atkin SL
- Subjects
- Duplicate Publications as Topic
- Published
- 2005
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29. Heat shock proteins in vascular disease--a review.
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Mehta TA, Greenman J, Ettelaie C, Venkatasubramaniam A, Chetter IC, and McCollum PT
- Subjects
- Aortic Diseases immunology, Aortic Diseases metabolism, Carotid Artery Diseases immunology, Carotid Artery Diseases metabolism, Coronary Disease immunology, Coronary Disease metabolism, Heat-Shock Proteins immunology, Humans, Peripheral Vascular Diseases immunology, Peripheral Vascular Diseases metabolism, Arteriosclerosis immunology, Arteriosclerosis metabolism, Heat-Shock Proteins physiology
- Abstract
Introduction: There is growing evidence that heat shock proteins (HSPs), a family of stress-inducible proteins may be involved in the pathogenesis of atherosclerotic vascular diseases. Here, we systematically review the evidence behind this notion., Methods: A detailed literature search and extensive bibliographic review of literature relating to HSPs and atherosclerotic vascular disease., Results: Atherosclerotic vascular disease is classified into four main areas of presentation: carotid, coronary, aortic and peripheral vascular disease, for consideration in this review. In each of these vascular diseases, the evidence linking HSPs and atherosclerosis is outlined in a systematic manner. Current evidence suggests that components of the immune system may be involved in the pathogenesis of atherosclerosis, with HSPs acting as auto-antigens in the immune response. HSPs are detected in atherosclerotic lesions and antibodies to HSPs are increased in patients with vascular disease; the rise often correlating with the severity of atherosclerosis. The levels of anti-HSP antibodies have been shown to be independent predictors of risk and have prognostic value., Conclusion: There is a strong link between heat shock protein expression and the principal manifestations of atherosclerotic vascular diseases. A better understanding of this involvement could lead to the development of new and improved treatment strategies.
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- 2005
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30. A comparative study of aortic wall stress using finite element analysis for ruptured and non-ruptured abdominal aortic aneurysms.
- Author
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Venkatasubramaniam AK, Fagan MJ, Mehta T, Mylankal KJ, Ray B, Kuhan G, Chetter IC, and McCollum PT
- Subjects
- Aged, Aged, 80 and over, Aortic Aneurysm, Abdominal diagnostic imaging, Female, Humans, Male, Stress, Mechanical, Tomography, X-Ray Computed, Aneurysm, Ruptured physiopathology, Aortic Aneurysm, Abdominal physiopathology, Finite Element Analysis, Models, Cardiovascular
- Abstract
Background: The decision to repair an asymptomatic abdominal aortic aneurysm (AAA) is currently based on diameter (> or =5.5 cm) alone. However, aneurysms less than 5.5 cm do rupture while some reach greater than 5.5 cm without rupturing. Hence the need to predict the risk of rupture on an individual patient basis is important. This study aims to calculate and compare wall stress in ruptured and non-ruptured AAA., Methods: The 3D geometries of AAA were derived from CT scans of 27 patients (12 ruptured and 15 non-ruptured). AAA geometry, systolic blood pressure and literature derived material properties, were utilised to calculate wall stress for individual AAA using finite element analysis., Results: Peak wall stress was significantly higher in the ruptured AAA (mean 1.02 MPa) than the non-ruptured AAA (mean 0.62 MPa). In patients with an identifiable site of rupture on CT scan, the area of peak wall stress correlated with rupture site., Conclusions: Peak wall stress can be calculated from routinely performed CT scans and may be a better predictor of risk of rupture than AAA diameter on an individual patient basis.
- Published
- 2004
- Full Text
- View/download PDF
31. The value of abdominal examination in the diagnosis of abdominal aortic aneurysm.
- Author
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Venkatasubramaniam AK, Mehta T, Chetter IC, Bryce J, Renwick P, Johnson B, Wilkinson A, and McCollum PT
- Subjects
- Aged, Aged, 80 and over, Body Mass Index, Female, Humans, Male, Middle Aged, Pilot Projects, Prospective Studies, Sensitivity and Specificity, Single-Blind Method, Aortic Aneurysm, Abdominal diagnosis, Physical Examination
- Abstract
Background: There is considerable variability in the reported value of clinical examination in the diagnosis of abdominal aortic aneurysms (AAA). This study aims to assess accuracy of abdominal examination by a doctor, a nurse and the patient in the diagnosis of AAA and whether this accuracy is related to the size of the aneurysm and/or the BMI of the patient., Methods: 164 patients, 138 men and 26 women, median age 71 years, consented to participate in this prospective, single blind, controlled study. Thirty-nine patients attending for carotid duplex were used as controls. Abdominal examination was performed by a doctor and a nurse. Patients then performed self-examination., Results: Examination by a doctor, a nurse and the patient were similar in accuracy in diagnosing/excluding AAA which was directly related to AAA size and patient BMI. The Negative Predicted Value of abdominal examination exceeds 0.9 with AAA diameters > or =4 cm and the Positive Predictive Value exceeds 0.8 with AAA diameters > or =5 cm., Conclusions: Abdominal examination by a doctor, a nurse and the patient is of value in the exclusion and diagnosis of significant AAA. It should be promoted and may represent a useful adjunct to population screening with ultrasound.
- Published
- 2004
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- View/download PDF
32. The role of hyperbaric oxygen therapy in ischaemic diabetic lower extremity ulcers: a double-blind randomised-controlled trial.
- Author
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Abidia A, Laden G, Kuhan G, Johnson BF, Wilkinson AR, Renwick PM, Masson EA, and McCollum PT
- Subjects
- Aged, Aged, 80 and over, Anxiety economics, Anxiety psychology, Cost-Benefit Analysis economics, Depression economics, Depression psychology, Depression therapy, Diabetic Foot economics, Diabetic Foot psychology, Double-Blind Method, Female, Follow-Up Studies, Humans, Ischemia economics, Ischemia psychology, Leg Ulcer economics, Leg Ulcer psychology, Lower Extremity pathology, Male, Middle Aged, Quality of Life, Treatment Outcome, United Kingdom, Diabetic Foot therapy, Hyperbaric Oxygenation economics, Ischemia therapy, Leg Ulcer therapy, Lower Extremity blood supply
- Abstract
Objective: ischaemic lower-extremity ulcers in the diabetic population are a source of major concern because of the associated high risk of limb-threatening complications. The aim of this study was to evaluate the role of hyperbaric oxygen in the management of these ulcers., Method: eighteen diabetic patients with ischaemic, non-healing lower-extremity ulcers were recruited in a double-blind study. Patients were randomly assigned either to receive 100% oxygen (treatment group) or air (control group), at 2.4 atmospheres of absolute pressure for 90 min daily (total of 30 treatments)., Results: healing with complete epithelialisation was achieved in five out of eight ulcers in the treatment group compared to one out of eight ulcers in the control group. The median decrease of the wound areas in the treatment group was 100% and in the control group was 52% (p=0.027). Cost-effectiveness analysis has shown that despite the extra cost involved in using hyperbaric oxygen, there was a potential saving in the total cost of treatment for each patient during the study., Conclusion: hyperbaric oxygen enhanced the healing of ischaemic, non-healing diabetic leg ulcers and may be used as a valuable adjunct to conventional therapy when reconstructive surgery is not possible.
- Published
- 2003
- Full Text
- View/download PDF
33. 28-Day emergency surgical re-admission rates as a clinical indicator of performance.
- Author
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Courtney ED, Ankrett S, and McCollum PT
- Subjects
- Diagnostic Errors, Emergencies, Emergency Service, Hospital statistics & numerical data, Hospital Information Systems standards, Humans, Length of Stay, Medical Audit, Middle Aged, Retrospective Studies, Surgery Department, Hospital statistics & numerical data, United Kingdom, Clinical Competence standards, Emergency Service, Hospital standards, Patient Readmission statistics & numerical data, Postoperative Complications epidemiology, Quality Indicators, Health Care, Surgery Department, Hospital standards
- Abstract
With the introduction of clinical governance, the NHS Executive has identified 28-day emergency re-admission rates as a clinical indicator to be used to assess and compare performance between NHS trusts. We undertook a 3-month retrospective audit of patients identified from the trust computer as having been re-admitted as an emergency within 28 days of discharge from the general surgical division. We wanted to examine reasons for re-admission, possible errors in coding and any preventable factors in these patients subsequently re-admitted acutely.
- Published
- 2003
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34. Fluvastatin induces apoptosis of vascular endothelial cells: blockade by glucocorticoids.
- Author
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Newton CJ, Xie YX, Burgoyne CH, Adams I, Atkin SL, Abidia A, and McCollum PT
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- Cell Cycle drug effects, Cell Line, Dexamethasone pharmacology, Dose-Response Relationship, Drug, Endothelium, Vascular cytology, Flow Cytometry, Fluvastatin, Glucocorticoids pharmacology, Humans, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction drug effects, Anticholesteremic Agents pharmacology, Apoptosis drug effects, Endothelium, Vascular drug effects, Fatty Acids, Monounsaturated pharmacology, Hydroxymethylglutaryl-CoA Reductase Inhibitors pharmacology, Indoles pharmacology
- Abstract
Statins block de novo synthesis of cholesterol by inhibiting the enzyme, HMG CoA reductase. The product of this reaction, mevalonic acid, is also a precursor of isoprenoids, molecules required for the activation of signaling G-proteins, such as Ras. Signal transduction pathways involving Ras are important for cell survival and this may be why statins induce apoptotic death of several cell types. Given that statins are used to treat vascular disease, surprisingly no studies have been conducted on vascular endothelial cells. Here we show that fluvastatin (FS), at concentrations from 1-2 microM, blocks growth and induces apoptosis of the endothelial cell line, EA.hy 926. Considerable redundancy is known to exist in cell signaling and in vivo toxicity of FS might be prevented by other signaling pathways, like those activated by adrenal or sex steroids. RT-PCR analysis revealed the expression of the androgen and glucocorticoid receptor in EA.hy 926 cells. Although the androgen, dihydrotestesterone (DHT) had no effect, the glucocorticoid, dexamethasone (Dex), blocked FS-induced apoptosis. Cell cycle analysis revealed that 24 h exposure to FS prevented cells from leaving G(1) and 24-48 h later a marked sub-G(1) peak was observed. Dex was able to reduce the sub-G(1) peak, but it failed to block accumulation of cells in G(1), indicating that it's effect was specific for blockade of apoptosis, and not specific to an effect on FS alone. This study strongly suggests that glucocorticoids have a role to play in preventing vascular injury and they may provide the reason why statins are not inherently toxic to vascular endothelial cells, in vivo.
- Published
- 2003
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35. A Bayesian hierarchical approach to comparative audit for carotid surgery.
- Author
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Kuhan G, Marshall EC, Abidia AF, Chetter IC, and McCollum PT
- Subjects
- Adult, Aged, Aged, 80 and over, Carotid Artery Diseases complications, Carotid Artery Diseases mortality, Female, Humans, Male, Middle Aged, Reproducibility of Results, Retrospective Studies, Survival Rate, Bayes Theorem, Carotid Artery Diseases surgery, Clinical Competence statistics & numerical data, Endarterectomy, Carotid statistics & numerical data, Medical Audit statistics & numerical data, Models, Statistical, Outcome Assessment, Health Care statistics & numerical data
- Abstract
Objectives: the aim of this study was to illustrate how a Bayesian hierarchical modelling approach can aid the reliable comparison of outcome rates between surgeons., Design: retrospective analysis of prospective and retrospective data., Materials: binary outcome data (death/stroke within 30 days), together with information on 15 possible risk factors specific for CEA were available on 836 CEAs performed by four vascular surgeons from 1992-99. The median patient age was 68 (range 38-86) years and 60% were men., Methods: the model was developed using the WinBUGS software. After adjusting for patient-level risk factors, a cross-validatory approach was adopted to identify "divergent" performance. A ranking exercise was also carried out., Results: the overall observed 30-day stroke/death rate was 3.9% (33/836). The model found diabetes, stroke and heart disease to be significant risk factors. There was no significant difference between the predicted and observed outcome rates for any surgeon (Bayesian p -value>0.05). Each surgeon had a median rank of 3 with associated 95% CI 1.0-5.0, despite the variability of observed stroke/death rate from 2.9-4.4%. After risk adjustment, there was very little residual between-surgeon variability in outcome rate., Conclusions: Bayesian hierarchical models can help to accurately quantify the uncertainty associated with surgeons' performance and rank.
- Published
- 2002
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- View/download PDF
36. POSSUM and P-POSSUM overpredict mortality for carotid endarterectomy.
- Author
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Kuhan G, Abidia AF, Wijesinghe LD, Chetter IC, Johnson BF, Wilkinson AR, Renwick PM, and McCollum PT
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Logistic Models, Male, Middle Aged, Predictive Value of Tests, Prospective Studies, Retrospective Studies, Carotid Artery Diseases mortality, Carotid Artery Diseases surgery, Endarterectomy, Carotid mortality, Linear Models, Outcome Assessment, Health Care
- Abstract
Objectives: the aim was to test the predictive accuracy of POSSUM and P-POSSUM on patients undergoing CEA., Design: retrospective and prospective study., Materials: 499 CEAs performed by four vascular surgeons from a single unit from 1992-99. The median age was 68 (range 38-86) and 60% were men., Methods: physiological parameters, operative parameters and the 30-day mortality were collected. Predicted mortality for each patient was calculated using POSSUM and P-POSSUM equations. Patients were stratified into risk groups and observed and predicted deaths were compared. Accuracy of the prediction was assessed using chi-squared analysis., Results: the observed 30-day mortality was 1.8% (9/499). The predicted deaths using POSSUM and P-POSSUM analysis were 49 and 25 respectively compared to nine observed deaths. There was significant evidence of lack of fit of both models in predicting mortality (chi-squared analysis, p<0.05)., Conclusions: POSSUM and P-POSSUM overpredict mortality and are unsuitable for comparative audit of CEA. Models developed specific for CEA might accurately predict mortality., (Copyright 2002 Harcourt Publishers Limited.)
- Published
- 2002
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37. Risk modelling study for carotid endarterectomy.
- Author
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Kuhan G, Gardiner ED, Abidia AF, Chetter IC, Renwick PM, Johnson BF, Wilkinson AR, and McCollum PT
- Subjects
- Adult, Aged, Aged, 80 and over, Diabetes Mellitus mortality, Female, Heart Diseases mortality, Humans, Logistic Models, Male, Medical Audit, Middle Aged, Prognosis, Prospective Studies, Regression Analysis, Retrospective Studies, Risk Assessment, Risk Factors, Stroke mortality, Endarterectomy, Carotid mortality, Stroke prevention & control
- Abstract
Background: The aims of this study were to identify factors that influence the risk of stroke or death following carotid endarterectomy (CEA) and to develop a model to aid in comparative audit of vascular surgeons and units., Methods: A series of 839 CEAs performed by four vascular surgeons between 1992 and 1999 was analysed. Multiple logistic regression analysis was used to model the effect of 15 possible risk factors on the 30-day risk of stroke or death. Outcome was compared for four surgeons and two units after adjustment for the significant risk factors., Results: The overall 30-day stroke or death rate was 3.9 per cent (29 of 741). Heart disease, diabetes and stroke were significant risk factors. The 30-day predicted stroke or death rates increased with increasing risk scores. The observed 30-day stroke or death rate was 3.9 per cent for both vascular units and varied from 3.0 to 4.2 per cent for the four vascular surgeons. Differences in the outcomes between the surgeons and vascular units did not reach statistical significance after risk adjustment., Conclusion: Diabetes, heart disease and stroke are significant risk factors for stroke or death following CEA. The risk score model identified patients at higher risk and aided in comparative audit.
- Published
- 2001
- Full Text
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38. Tibial and peroneal artery bypasses using polytetrafluoroethylene (PTFE) with an interposition vein cuff.
- Author
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Stonebridge PA, Naidu S, Colgan MP, Moore DJ, Shanik DG, and McCollum PT
- Subjects
- Aged, Aged, 80 and over, Female, Humans, Ischemia surgery, Leg blood supply, Male, Middle Aged, Peripheral Vascular Diseases surgery, Quality of Life, Retrospective Studies, Tibial Arteries pathology, Tibial Arteries surgery, Treatment Outcome, Vascular Patency, Blood Vessel Prosthesis, Polytetrafluoroethylene, Veins transplantation
- Abstract
Unlabelled: The combined results of femoro-distal bypasses using prosthetic material with vein cuffs from two separate vascular units is presented., Method: Over the last five years, 89 infrainguinal bypasses using polytetrafluoroethylene (PTFE) with a distal interposition vein cuff to a tibial artery have been performed in two centres. All operations were for critical limb ischaemia. The mean age was 72 years (47-90), there were 46 males and 43 females, 27 of whom were diabetic. Twenty-eight patients had a history of angina and/or previous myocardial infarct. The median follow-up was 12 months (0-68 months)., Results: During the follow-up period there were 28 deaths, 35 major limb amputations and 44 graft failures. The graft patency rates at 12 and 24 months were 50 and 32%, and limb salvage rates were 53 and 44%, respectively. The patient survival rates were 66 and 61%, respectively., Conclusion: The authors believe that the likely improvement in pain free quality of life the patient may enjoy with a successful bypass shifts the balance in some individuals towards bypass surgery using PTFE with a vein cuff to a tibial artery when such an option is possible.
- Published
- 2000
39. An audit of emergency abdominal aortic aneurysm repair to establish the necessity for an emergency vascular surgical rota.
- Author
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McCollum PT
- Subjects
- Emergency Service, Hospital organization & administration, Humans, Vascular Surgical Procedures organization & administration, Aortic Aneurysm, Abdominal surgery, Aortic Rupture surgery
- Published
- 1999
40. Vascular surgical society of great britain and ireland: limb salvage in the octogenarian
- Author
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Ramamoorthy P, Johnson BJ, Wilkinson AR, Galloway JM, and McCollum PT
- Abstract
BACKGROUND: Critical limb ischaemia (CLI) presents a unique set of problems in the elderly patient. Foremost among these is the much greater likelihood of loss of independence and reduced quality of life if major amputation is required. For this reason it has been this unit's policy to attempt reconstructive vascular surgery in almost all cases of CLI. The outcome of this policy was examined. METHODS: All patients had surgery performed under one consultant and data were entered prospectively on to a database. RESULTS: Risk factors included diabetes (17 per cent), smoking (78 per cent) and ischaemic heart disease (31 per cent). Some 127 patients had either femoropopliteal (59), femorodistal (64) or popliteal-distal grafts (four) performed for limb-threatening ischaemia. Follow-up was performed at 3, 6 and 12 months and then at annual intervals until death. Seventeen of these patients required a subsequent major amputation, 12 at the below-knee and five at the above-knee level. Mean follow-up was 2 years. The perioperative mortality rate was 15 per cent, although eight of these patients were admitted with acute or chronic ischaemia. Cumulative graft secondary patency rate was 68 per cent at 4 years for vein grafts. Some 95 per cent of patients with patent grafts were independently mobile. CONCLUSION: Excellent results can be achieved for limb salvage with a relatively low morbidity in this group. Elderly patients with CLI do not live long and avoidance of amputation is particularly desirable in order to maximize the quality of their remaining life.
- Published
- 1999
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41. Accuracy of the recording of operative events by the Scottish Morbidity Record 1 (SMR1) for a teaching hospital vascular unit.
- Author
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Raza Z, Holdsworth RJ, and McCollum PT
- Subjects
- Cardiovascular Surgical Procedures standards, Data Collection, Health Planning, Hospitals, Teaching statistics & numerical data, Humans, Medical Records statistics & numerical data, Morbidity, Patient Admission statistics & numerical data, Scotland, Cardiovascular Surgical Procedures statistics & numerical data, Databases, Factual, Diagnosis-Related Groups statistics & numerical data, Hospitals, Teaching standards, Medical Records standards, Quality Assurance, Health Care
- Abstract
Objective: To determine the accuracy of operative data collected for the Scottish Morbidity Record 1 (SMR1)., Design: Retrospective comparative analysis of operative data recorded by the Scottish Office Information and Statistics Division (ISD) with that recorded in a locally held vascular database where the clinical information was entered by medical personnel., Subjects: All patients with a codeable operative procedure carried out under the care of a single consultant vascular surgeon in a Regional Vascular Unit in 1994., Results: A total of 840 admissions involving at least one OPCS4 code were recorded in the Vascular Database and 793 by the Scottish Office ISD. Although there was good agreement of the total number of operations and admissions, operative codes for 23 patients undergoing major abdominal aortic surgery and 19 undergoing major limb reconstruction were not recorded by the ISD. This represents 14% of total major arterial reconstructions in a single year., Conclusion: Accurate data collection has wide implications for research, monitoring future health trends, and planning hospital bed numbers. SMR1 data may accurately record total number of admissions and operations but is poor at distinguishing between those admissions that may be resource-intensive.
- Published
- 1999
42. Audit of the effect of introducing local guidelines for referral for carotid duplex scanning.
- Author
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Holdsworth RJ, Bryce JS, and McCollum PT
- Subjects
- Humans, Medical Audit, Referral and Consultation statistics & numerical data, Scotland, Carotid Stenosis diagnostic imaging, Ultrasonography, Doppler, Duplex
- Abstract
Guidelines for referral of patients for carotid duplex scanning were introduced stating that scans were only indicated for patients with hemispheric localising symptoms or asymptomatic bruits. A 19% reduction in referral rate was seen for new scans in a one year period. The number of "inappropriate" requests fell from 27.6% in 1994 to 12.8% in 1995. There was no reduction in the numbers of patients identified with effectively occult asymptomatic disease who may have been suitable for surgery in the same period. Guideline introduction had the effect of reducing unnecessary scans without any effect on the overall pick-up, rate for carotid disease.
- Published
- 1999
- Full Text
- View/download PDF
43. Aortic bifurcation reconstruction: use of the Memotherm self-expanding nitinol stent for stenoses and occlusions.
- Author
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Houston JG, McCollum PT, Stonebridge PA, Raza Z, and Shaw JW
- Subjects
- Adult, Aged, Aged, 80 and over, Alloys, Angiography, Angioplasty, Balloon, Aortic Diseases diagnostic imaging, Arteriosclerosis diagnostic imaging, Female, Follow-Up Studies, Humans, Iliac Artery diagnostic imaging, Iliac Artery surgery, Male, Middle Aged, Retrospective Studies, Treatment Outcome, Vascular Patency, Aortic Diseases surgery, Arteriosclerosis surgery, Stents
- Abstract
Purpose: To assess the technical success, initial clinical outcome, and intermediate follow-up of the Memotherm nitinol self-expanding stent in aortic bifurcation reconstruction., Methods: Thirty-three patients (13 male, 20 female), mean age 64 years, were treated, who had symptoms classified by the Surgical Vascular Society/International Society of Cardiovascular Surgery (SVS/ICVS) classification as grade 2 in 11 (33%), grade 3 in 19 (58%) and grade 4 in 3 (9%) patients. Lesions were classified according to severity and type. Indications for placement of a Memotherm nitinol self-expanding stent were failed angioplasty in 14 (42%), chronic occlusions in 12 (37%), and complex stenoses in seven (21%) patients., Results: Sixty-seven stents were technically successfully placed in 66 aorto-iliac segments in 33 patients, with one major complication. Initial clinical outcome was improvement in 25 (81%), no change in four (13%), and a worsening in two (6%) patients by Rutherford criteria. Mean early ankle/brachial pressure index (ABI) gain was 0. 27 for occlusions and 0.05 for stenoses. Clinical follow-up was obtained in all patients, with retrospective angiographic follow-up in 28 (85%) at a mean of 16 months (range 12-26 months). The decrease in ABI and the decrease in angiographic luminal diameter at follow-up was determined as the "late loss." The mean ABI late losses were -0.06, 0.00, and 0.09, and the mean angiographic late losses were 6.7%, 10% and 14% for occlusions, stenoses, and normal segments respectively. Primary clinical patency was 96%, primary angiographic patency was 89%, and secondary angiographic patency was 93%., Conclusion: The high technical success of stent placement, the low complication rates for aortic bifurcation reconstruction using the Memotherm self-expanding stent, and high clinical and angiographic patency maintained at intermediate follow-up support their use in aortic bifurcation reconstruction.
- Published
- 1999
- Full Text
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44. Disruption of skin perfusion following longitudinal groin incision for infrainguinal bypass surgery.
- Author
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Raza Z, Newton DJ, Harrison DK, McCollum PT, and Stonebridge PA
- Subjects
- Aged, Aged, 80 and over, Female, Femoral Artery surgery, Groin surgery, Humans, Iliac Artery surgery, Ischemia physiopathology, Longitudinal Studies, Male, Microcirculation physiopathology, Middle Aged, Oxygen blood, Popliteal Artery surgery, Postoperative Complications physiopathology, Surgical Wound Infection etiology, Surgical Wound Infection physiopathology, Arterial Occlusive Diseases surgery, Ischemia etiology, Leg blood supply, Postoperative Complications etiology, Skin blood supply
- Abstract
Objective: The objective of our study was to investigate whether such an incision results in a reduction in blood flow, and therefore haemoglobin oxygen saturation, across the wound., Design: Microvascular oxygenation was measured with lightguide spectrophotometry in 21 patients undergoing femoropopliteal or femorodistal bypass procedures. A series of measurements were made in the groin, medial and lateral to the surface marking of the femoral artery. The mean oxygen saturation on each side was calculated, and the contra-lateral groin was used as a control. The measurements were repeated at 2 and 7 days postop., Results: Oxygen saturation in the skin of the operated groins was increased significantly from baseline at 2 days postop (f = 25.80, p < 0.001) and had begun to return to normal by day 7. The rise was more marked on the lateral side of the wound than on the medial (f = 12.32, p < 0.001). There was no such difference in the control groins. All wounds healed at 10 days., Conclusions: These results show a significant difference in skin oxygenation between the lateral and medial sides of the groin following longitudinal incision. This may contribute to the relatively high incidence of postoperative infection in these wounds.
- Published
- 1999
- Full Text
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45. Management of iliac occlusions with a new self-expanding endovascular stent.
- Author
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Raza Z, Shaw JW, Stonebridge PA, and McCollum PT
- Subjects
- Aged, Aged, 80 and over, Angioplasty, Ankle blood supply, Aorta, Abdominal, Arterial Occlusive Diseases diagnostic imaging, Arterial Occlusive Diseases surgery, Blood Pressure physiology, Brachial Artery physiology, Combined Modality Therapy, Equipment Design, Female, Follow-Up Studies, Hematoma etiology, Humans, Iliac Artery diagnostic imaging, Iliac Artery surgery, Male, Middle Aged, Safety, Thrombosis etiology, Treatment Outcome, Ultrasonography, Doppler, Vascular Patency, Arterial Occlusive Diseases therapy, Iliac Artery pathology, Stents adverse effects
- Abstract
Objectives: To determine the patency and acceptability of the Memotherm endovascular stent in the treatment of iliac arterial occlusions., Materials and Methods: Twenty-two patients (12 males and 10 females) underwent stenting of iliac occlusions of the aortoiliac bifurcation, the common iliac artery and the external iliac artery. All patients were reassessed at 3, 6 and 12 month intervals and then yearly to evaluate their symptoms and Doppler pressure measurements. Comparison was made with results from other studies treating iliac occlusions by angioplasty alone or combined with stenting., Results: Out of 22 patients, 21 had an immediate and sustained improvement over the whole of the follow-up period. The Ankle-brachial Index (ABI) increased from a mean value of 0.49 to 0.81 3-months postprocedure and improved to 0.85 at 12 months (paired t-test p < 0.001). At 6 and 12 months the stent patency remained at 95.5%, which compares favourably with other studies. There were four minor and one major complication associated with the stenting procedure., Conclusions: The Memothern self-expanding stent is a useful, safe and effective device suitable for the majority of iliac occlusions. Further long-term evaluation is warranted to confirm its advantages over open surgery.
- Published
- 1998
- Full Text
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46. Carotid endarterectomy in the U.K. and Ireland: audit of 30-day outcome. The Audit Committee for the Vascular Surgical Society.
- Author
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McCollum PT, da Silva A, Ridler BD, and de Cossart L
- Subjects
- Adult, Aged, Aged, 80 and over, Atrial Fibrillation complications, Cerebrovascular Disorders complications, Cerebrovascular Disorders prevention & control, Cerebrovascular Disorders surgery, Humans, Ireland, Ischemic Attack, Transient surgery, Length of Stay, Middle Aged, Postoperative Complications, Prospective Studies, Referral and Consultation, Risk Factors, United Kingdom, Endarterectomy, Carotid methods, Endarterectomy, Carotid statistics & numerical data, Medical Audit
- Abstract
Objectives and Design: A prospective study of 709 patients undergoing carotid surgery in the U.K. and Ireland was performed to evaluate the performance of vascular surgeons., Materials and Methods: Fifty-nine surgeons (range 2-39 cases each) were sampled and all patients undergoing surgery over a 6-month period (1 March 1994-31 August 1994) were included in the study. Indications for surgery were TIA (35.9%), AF (23.3%), CVA (21.4%) and "others" (19.6%)., Results: Mean ipsilateral stenosis was 82% (30%-99%). Thirty-one percent of patients had preoperative neurological consults. Shunts were used in 67.6%, tacking sutures in 40.1%, drains in 71.9% and patches in 54.4% of cases. At 30 days there were nine (1.3%) deaths (four cardiac, three neurological). There were 15 ipsilateral postoperative CVAs (2.1%); 19% of patients had one or more complication, usually minor. Statistical analysis showed no independent risk factor for CVA other than seniority of the surgeon., Conclusions: A combined stroke/death rate of 3% for the series was obtained at 30 days for all cases. This large, validated study suggests that members of the Vascular Society of G.B. and Ireland currently have a very low morbidity/mortality rate for performing carotid surgery. Continued audit is required to ensure that this quality of service does not deteriorate.
- Published
- 1997
- Full Text
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47. Mesenteric revascularisation for acute-on-chronic intestinal ischaemia.
- Author
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Holdsworth RJ, Raza Z, Naidu S, and McCollum PT
- Subjects
- Acute Disease, Aged, Chronic Disease, Female, Humans, Male, Middle Aged, Treatment Outcome, Intestines blood supply, Ischemia surgery, Mesenteric Arteries surgery
- Abstract
Eleven patients (eight women) underwent urgent revascularisation for acute-on-chronic mesenteric ischaemia. Four patients had dual vessel and seven single vessel reconstructions. Two patients underwent simultaneous bowel resection and one patient has had three separate grafts to the superior mesenteric artery. There were two peri-operative deaths and three have died in the late follow-up period after 18, 24 and 36 months. The remainder have survived for between five and 63 months. Revascularisation for acute-on-chronic mesenteric ischaemia has been shown to be technically possible and of substantial benefit to patients who would otherwise be treated as terminal cases.
- Published
- 1997
- Full Text
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48. Glutaraldehyde-tanned bovine carotid artery graft for infrainguinal vascular reconstruction: 5-year follow-up.
- Author
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Holdsworth RJ, Naidu S, Gervaz P, and McCollum PT
- Subjects
- Aged, Animals, Carotid Arteries, Cattle, Cohort Studies, Female, Follow-Up Studies, Humans, Male, Polytetrafluoroethylene, Time Factors, Vascular Patency, Bioprosthesis, Blood Vessel Prosthesis, Femoral Artery surgery, Graft Occlusion, Vascular epidemiology, Intermittent Claudication surgery, Popliteal Artery surgery
- Abstract
Objective: To assess the long-term patency of a modified biological conduit, the glutaraldehyde-tanned bovine carotid artery, in above-knee infrainguinal arterial reconstruction., Patients and Methods: Prospective follow-up of a cohort of 58 above-knee femoropopliteal grafts in 55 patients. Graft patency was assessed at yearly intervals with doppler ankle pressure measurements., Results: The median follow-up period has been 67 months. Nine grafts occluded within 30 days of surgery and a further 19 graft closures have been observed in the follow-up period. The overall cumulative primary graft patency at 1, 3 and 5 years was 70%, 61% and 56%, respectively. If the 30-day graft failures are excluded, the primary graft patency rises to 83%, 74% and 68% at 1, 3 and 5 years, respectively. Six limbs have been amputated, four above the knee and two below the knee. There were no graft aneurysms and no graft infections., Conclusion: Results indicate that the modified bovine carotid artery graft with an above-knee anastomosis does not seem to be inferior to PTFE, but is inferior to reversed vein. Modified biological conduits offer a reasonable alternative to synthetic grafts for infrainguinal arterial reconstruction and appear to maintain acceptable long-term mechanical stability.
- Published
- 1997
- Full Text
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49. Gender, age and carotid plaque morphology.
- Author
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Holdsworth RJ, Bryce JS, Harrison DK, and McCollum PT
- Subjects
- Adult, Age Distribution, Aged, Aged, 80 and over, Carotid Artery Thrombosis pathology, Carotid Stenosis pathology, Female, Humans, Male, Middle Aged, Risk Factors, Sex Distribution, United Kingdom epidemiology, Carotid Artery Thrombosis epidemiology, Carotid Stenosis epidemiology
- Abstract
Objectives: To examine the relationship between patients gender, age and the development of different types of internal carotid artery plaque., Design: Prospective open clinical study., Methods: 455 carotid duplex scans with a greater than 50% stenosis were analysed in terms of gender, age, degree of stenosis symptoms and plaque morphology., Results: There were 238 males (52.3%) and 217 females. Of 120 patients with type I plaque 86 were male (71.7%, chi 2 = 23.4, p = 0.000002). This high incidence of type I (haemorrhagic) plaque in men was accompanied by a higher degree of stenosis (chi 2 = 11.7 p = 0.0006) but was independent of the age of the patients and the presence of symptoms., Conclusions: Although this study supports the view that men have more severe carotid artery disease, it does not to affect a younger age group. The higher degree of stenosis and its association with haemorrhagic plaque is not translated into an increase in symptoms in men.
- Published
- 1997
50. The radiological appearance of atherosclerotic popliteal artery aneurysms: the "dog-leg" sign.
- Author
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Holdsworth RJ, Raza Z, Naidu S, and McCollum PT
- Subjects
- Humans, Radiography, Aneurysm diagnostic imaging, Popliteal Artery diagnostic imaging
- Abstract
The radiological appearance of popliteal aneurysms is described. Althought the lumen of the artery is often of normal diameter there is elongation of the vessel which frequently results in an acute "dog-leg". This sign has not been previously described.
- Published
- 1997
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