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Myocardial injury due to ischaemia within 30 days of non-cardiac surgery is prognostically relevant. We aimed to determine the discrimination, calibration, accuracy, sensitivity and specificity of single-layer and multiple-layer neural networks for myocardial injury and death to 30 postoperative days. We analysed data from 24,589 participants in the vascular events in noncardiac surgery patients cohort evaluation study. Validation was performed on a randomly selected subset of the study population. Discrimination for myocardial injury by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.70 (0.69-0.72) vs. 0.71 (0.70-0.73) with variables available before surgical referral, p < 0.001; 0.73 (0.72-0.75) vs. 0.75 (0.74-0.76) with additional variables available on admission, but before surgery, p < 0.001; and 0.76 (0.75-0.77) vs. 0.77 (0.76-0.78) with the addition of subsequent variables, p < 0.001. Discrimination for death by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.71 (0.66-0.76) vs. 0.74 (0.71-0.77) with variables available before surgical referral, p = 0.04; 0.78 (0.73-0.82) vs. 0.83 (0.79-0.86) with additional variables available on admission but before surgery, p = 0.01; and 0.87 (0.83-0.89) vs. 0.87 (0.85-0.90) with the addition of subsequent variables, p = 0.52. The accuracy of the multiple-layer model for myocardial injury and death with all variables was 70% and 89%, respectively.

Data sharing: The PHOSP-COVID study protocol, consent form, definition, and derivation of clinical characteristics and outcomes, training materials, regulatory documents, information about requests for data access, and other relevant study materials are available online. UK Biobank information can be released once necessary approvals have been obtained. Other data (eg, the R code and protocol) will be made available on reasonable request to the corresponding author. Copyright © 2023 The Author(s). Background: Sleep disturbance is common following hospital admission both for COVID-19 and other causes. The clinical associations of this for recovery after hospital admission are poorly understood despite sleep disturbance contributing to morbidity in other scenarios. We aimed to investigate the prevalence and nature of sleep disturbance after discharge following hospital admission for COVID-19 and to assess whether this was associated with dyspnoea. Methods: CircCOVID was a prospective multicentre cohort substudy designed to investigate the effects of circadian disruption and sleep disturbance on recovery after COVID-19 in a cohort of participants aged 18 years or older, admitted to hospital for COVID-19 in the UK, and discharged between March, 2020, and October, 2021. Participants were recruited from the Post-hospitalisation COVID-19 study (PHOSP-COVID). Follow-up data were collected at two timepoints: an early time point 2–7 months after hospital discharge and a later time point 10–14 months after hospital discharge. Sleep quality was assessed subjectively using the Pittsburgh Sleep Quality Index questionnaire and a numerical rating scale. Sleep quality was also assessed with an accelerometer worn on the wrist (actigraphy) for 14 days. Participants were also clinically phenotyped, including assessment of symptoms (ie, anxiety [Generalised Anxiety Disorder 7-item scale questionnaire], muscle function [SARC-F questionnaire], dyspnoea [Dyspnoea-12 questionnaire] and measurement of lung function), at the early timepoint after discharge. Actigraphy results were also compared to a matched UK Biobank cohort (non-hospitalised individuals and recently hospitalised individuals). Multivariable linear regression was used to define associations of sleep disturbance with the primary outcome of breathlessness and the other clinical symptoms. PHOSP-COVID is registered on the ISRCTN Registry (ISRCTN10980107). Findings: 2320 of 2468 participants in the PHOSP-COVID study attended an early timepoint research visit a median of 5 months (IQR 4–6) following discharge from 83 hospitals in the UK. Data for sleep quality were assessed by subjective measures (the Pittsburgh Sleep Quality Index questionnaire and the numerical rating scale) for 638 participants at the early time point. Sleep quality was also assessed using device-based measures (actigraphy) a median of 7 months (IQR 5–8 months) after discharge from hospital for 729 participants. After discharge from hospital, the majority (396 [62%] of 638) of participants who had been admitted to hospital for COVID-19 reported poor sleep quality in response to the Pittsburgh Sleep Quality Index questionnaire. A comparable proportion (338 [53%] of 638) of participants felt their sleep quality had deteriorated following discharge after COVID-19 admission, as assessed by the numerical rating scale. Device-based measurements were compared to an age-matched, sex-matched, BMI-matched, and time from discharge-matched UK Biobank cohort who had recently been admitted to hospital. Compared to the recently hospitalised matched UK Biobank cohort, participants in our study slept on average 65 min (95% CI 59 to 71) longer, had a lower sleep regularity index (–19%; 95% CI –20 to –16), and a lower sleep efficiency (3·83 percentage points; 95% CI 3·40 to 4·26). Similar results were obtained when comparisons were made with the non-hospitalised UK Biobank cohort. Overall sleep quality (unadjusted effect estimate 3·94; 95% CI 2·78 to 5·10), deterioration in sleep quality following hospital admission (3·00; 1·82 to 4·28), and sleep regularity (4·38; 2·10 to 6·65) were associated with higher dyspnoea scores. Poor sleep quality, deterioration in sleep quality, and sleep regularity were also associated with impaired lung function, as assessed by forced vital capacity. Depending on the sleep metric, anxiety mediated 18–39% of the effect of sleep disturbance on dyspnoea, while muscle weakness mediated 27–41% of this effect. Interpretation: Sleep disturbance following hospital admission for COVID-19 is associated with dyspnoea, anxiety, and muscle weakness. Due to the association with multiple symptoms, targeting sleep disturbance might be beneficial in treating the post-COVID-19 condition. Funding: UK Research and Innovation, National Institute for Health Research, and Engineering and Physical Sciences Research Council. UK Research and Innovation, National Institute for Health Research, and Engineering and Physical Sciences Research Council.

Background Frailty is an established risk factor for poorer outcomes in older hospitalised patients, but most measures require additional clinical review. Such formal frailty assessments are rarely undertaken in acute cardiac patients. However, routine electronic health records increasingly record health and functional deficits that together may represent the frailty phenotype. Purpose To report the outcomes of acute cardiac patients in relation to an automated frailty measurement, derived from routine electronic health records. Methods This retrospective observational cohort study included consecutive patients aged ≥70 years old who were managed under the specialist care of a consultant cardiologist between April 2016 and August 2020 in three acute hospitals across Edinburgh, Scotland. The Continuous Dynamic Evaluation of Frailty (CODE-f) score was derived from national Care Assurance Standards data that is mandated for older patient hospital care. This includes measures of cognition, functional dependence, nutrition, falls risk, continence, skin health and mobility. A total of 31 data points were included in an unweighted frailty index with scores ranging between 0 (no markers present) and 1 (all present). No CODE-f score was generated if insufficient data was completed (>33% missing). The primary outcome was mortality at 1 year after hospital admission. Secondary outcomes were length of first (index) hospital stay and the number of days spent alive and out of hospital in the year after index admission (“home time”). In a nested cohort study of 318 consecutive patients at one hospital site, the Clinical Frailty Scale (CFS) was determined from manual electronic case note review for comparison with CODE-f scores. Results A total of 2,406 patients were included (mean age 79±6 years, 60% male). The CODE-f could be generated in 2,158 (90%) patients, with a mean score of 0.20±0.21. The primary outcome occurred in 352 (15%) patients. Those in the highest scoring CODE-f quartile (>0.35) had greater than 3-fold increased risk of death at 1 year compared to patients in the lowest quartile ( Conclusion An automated electronic health record measure can identify frail older adults at risk of poorer recovery and death after acute cardiac illness. This could inform complex treatment decisions and future care planning for this patient group. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Chief Scientist Office

Background Early rule-out pathways for myocardial infarction using high-sensitivity cardiac troponin are widely recommended in the assessment of patients with suspected acute coronary syndrome. Although developed in selected patients participating in research studies, these pathways are applied more widely in clinical practice where the diagnostic performance and effectiveness of these pathways may differ. Purpose To evaluate the performance of an early rule-out pathway for myocardial infarction using high-sensitivity cardiac troponin in selected and consecutive unselected patients with suspected acute coronary syndrome. Methods Presentation and serial high-sensitivity cardiac troponin I concentrations were measured in two cohorts of patients with suspected acute coronary syndrome presenting to the Emergency Departments across three acute care hospitals in Scotland. In the unselected cohort, electronic health record data were collected on consecutive patients in whom the usual care clinician measured cardiac troponin for suspected acute coronary syndrome. In the selected cohort, patients with suspected acute coronary syndrome were approached between 8am and 8pm by research staff and written informed consent obtained. In both cohorts, the performance of the High-STEACS early rule-out pathway was evaluated for an adjudicated diagnosis of myocardial infarction (type 1, type 4b or type 4c) during the index hospital admission. Results The unselected and selected patient cohorts comprised of 1,242 (median age 60 [interquartile range 47–75] years, 46% women) and 1,695 (median age 61 [52–73] years, 40% women) patients respectively. Myocardial infarction was diagnosed in 6% (74/1,242) and 14% (232/1,695) of patients in the unselected and selected patient cohorts respectively. More patients had myocardial infarction ruled-out in the unselected (74% [828/1,112] versus 66% [1,102/1,678]; P Conclusion The prevalence of myocardial infarction is lower in patients with suspected acute coronary syndrome evaluated in routine practice compared to those selected to participate in a research study. Whilst more patients have myocardial infarction accurately ruled out, the positive-predictive value in those ruled in is lower resulting in more hospital admissions with elevated cardiac troponin due to other conditions. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): British Heart FoundationMedical Research Council

Background Guidelines recommend fixed cardiac troponin thresholds for the assessment of patients with suspected acute coronary syndrome, however, performance varies in important patient groups as concentrations are influenced by age, sex and comorbidities. This limitation can be addressed using machine learning algorithms. Methods Machine learning algorithms were developed that integrate cardiac troponin concentrations at presentation or on serial testing with age, sex and clinical features in 10,038 consecutive emergency patients with suspected acute coronary syndrome. The primary outcome was an adjudicated diagnosis of type 1, type 4b or type 4c myocardial infarction. The best performing algorithm was selected for the CoDE-ACS (Collaboration for the Diagnosis and Evaluation of Acute Coronary Syndrome) decision-support tool, and performance was externally validated in 3,035 patients pooled from three prospective studies. Findings CoDE-ACS had excellent discrimination and calibration using cardiac troponin at presentation (area under curve [AUC] 0.959, 95% confidence interval 0.948–0.971, Brier score 0.040), in the pooled external validation cohort. At presentation, the rule-out score identified 62.1% (1,885/3,035) of all patients as low-probability of myocardial infarction with a 99.5% (99.1–99.7%) negative predictive value and 97.0% (96.3–97.6%) sensitivity. The rule-in score identified 8.3% (252/3,035) of patients as high-probability with an 83.7% (82.4–85.0%) positive predictive value and 98.5% (98.0–98.9%) specificity. Performance of the rule-out and rule-in scores was consistent across patient subgroups (Figure 1 and Figure 2). CoDE-ACS incorporating a second cardiac troponin measurement also had excellent discrimination and calibration (AUC 0.971 [0.962–0.980], Brier score 0.039) and refined the individualised probabilities in the 29.5% (898/3,035) of patients neither ruled-out or ruled-in at presentation to guide further investigation. Conclusions We developed and externally validated the CoDE-ACS decision-support tool using machine learning to aid in the diagnosis of myocardial infarction. CoDE-ACS had excellent diagnostic performance to rule-out and rule-in myocardial infarction at presentation, performed consistently across patient subgroups, and provided individualised probabilities to guide further care in those who require serial troponin measurements. Conclusions We developed and externally validated the CoDE-ACS decision-support tool using machine learning to aid in the diagnosis of myocardial infarction. CoDE-ACS had excellent diagnostic performance to rule-out and rule-in myocardial infarction at presentation, performed consistently across patient subgroups, and provided individualised probabilities to guide further care in those who require serial troponin measurements. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health ResearchBritish Heart Foundation

Background Acute myocardial injury and type 2 myocardial infarction typically occur in the setting of a concurrent illness. Differentiating acute myocardial injury from type 2 myocardial infarction is challenging as it relies on the assessment of myocardial ischaemia. Indeed, some have questioned whether this distinction is important, as patients with both conditions are at increased risk of future cardiovascular events. Whether this risk is similar and the role of identifying those with coronary artery disease is uncertain. Purpose To determine whether future risk of cardiovascular events and death differs in patients with type 2 myocardial infarction and acute myocardial injury according to the presence or absence of prior coronary artery disease. Methods We conducted a secondary analysis of a multi-centre randomised controlled trial of 48,282 consecutive patients with suspected acute coronary syndrome. Patients with an adjudicated index diagnosis of acute myocardial injury and type 2 myocardial infarction were stratified according to whether they were known previously to have coronary artery disease defined as prior coronary revascularisation, myocardial infarction, or angina. Cardiovascular death or myocardial infarction adjusted for the competing risk of non-cardiovascular death and all-cause death at one year was compared. Results In 9,115 patients with elevated cardiac troponin concentrations, 1,676 (18%) and 1,121 (12%) had acute myocardial injury and type 2 myocardial infarction, respectively. Patients with either condition known to have coronary artery disease were older (mean [standard deviation] age 78 [11] versus 73 [16] years) and more likely to be female (55% versus 45%) than those with no prior history. Coronary artery disease was previously identified in 40% (454/1,121) and 30% (509/1,167) of those with type 2 myocardial infarction and acute myocardial injury, respectively. Cardiovascular death or myocardial infarction at one year was more common in patients known to have coronary artery disease than those without for both acute myocardial injury (23% [115/509]) versus 14% [158/1,167]; P Conclusion Coronary artery disease is recognised in around one third of patients with acute myocardial injury and type 2 myocardial infarction and is associated with higher rates of cardiovascular events and all-cause death. Risk doubled in those with coronary artery disease and was similar whether the index diagnosis was myocardial injury or infarction, suggesting that coronary investigation and secondary prevention may have a role in both conditions. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The University of Edinburgh and British Heart Foundation

Background Implementation of a high-sensitivity cardiac troponin I assay with the sex-specific 99th centile as the diagnostic threshold identifies more patients with myocardial injury and infarction, but whether this impacts on long-term clinical outcomes is unknown. Purpose In a prespecified analysis of a stepped-wedge cluster-randomised controlled trial performed across ten hospitals in Scotland, we evaluated the impact of implementing a high-sensitivity cardiac troponin I assay on outcomes at 5 years in consecutive patients with suspected acute coronary syndrome. Methods Throughout the trial, all 48,282 patients had cardiac troponin I concentrations measured using both a contemporary (standard care) and high-sensitivity (implementation) assay. During standard care, results from the high-sensitivity assay were concealed and the contemporary assay was used to guide care. Hospitals were randomly allocated to early (n=5) or late (n=5) implementation of the high-sensitivity assay using the sex-specific 99th centile to guide care and results from the contemporary assay were concealed. Patients reclassified by the high-sensitivity assay were defined as those with cardiac troponin concentrations above the sex-specific 99th centile but below the contemporary assay diagnostic threshold. Subsequent myocardial infarction or all-cause death at 5 years was compared before and after implementation using an adjusted Cox proportional hazards model in those reclassified by the high-sensitivity assay and stratified by index diagnosis. Results Overall, 10,360 patients had cardiac troponin concentrations greater than the sex-specific 99th centile of whom 1,771 (17%) were reclassified by the high-sensitivity assay. Compared to those identified as having elevated cardiac troponin by the contemporary assay, patients reclassified by the high-sensitivity assay were more likely to have non-ischemic myocardial injury (54% versus 28%) and less likely to have type 1 myocardial infarction (33% versus 59%; P Conclusions In patients with suspected acute coronary syndrome, implementation of a high-sensitivity cardiac troponin assay was associated with a lower risk of subsequent myocardial infarction or death at 5 years. Improvements in outcome were greater in those with a diagnosis of non-ischemic myocardial injury rather than infarction. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): British Heart Foundation

Background Patients with suspected acute coronary syndrome in whom myocardial infarction has been ruled-out are at risk of future adverse cardiac events. However, the optimal approach to risk stratify and investigate these patients is uncertain. Methods We performed a prospective cohort study of 250 patients presenting to the Emergency Department with suspected acute coronary syndrome and troponin concentrations below the sex-specific 99th centile (16 ng/L for women and 34 ng/L for men). Patients were recruited in a 2:1 fashion stratified by peak high-sensitivity cardiac troponin I concentration above and below the early rule-out threshold of 5 ng/L (167 patients with intermediate troponin concentrations between 5 ng/L and the sex-specific 99th centile threshold and 83 patients with troponin concentrations Results Overall, 37.6% (94/250) of patients had normal coronary arteries whilst 36.0% (90/250) and 26.4% (66/250) had non-obstructive and obstructive coronary artery disease, respectively. Patients with intermediate troponin concentrations were more likely to have coronary artery disease than those with troponin concentrations Conclusions In patients with suspected acute coronary syndrome who have myocardial infarction ruled out, those with intermediate cardiac troponin concentrations are three-times more likely to have coronary artery disease than those with low troponin concentrations. Conversely anginal symptoms did not discriminate between those with and without coronary artery disease. Further studies are required to determine if targeting computed tomography coronary angiography to those with intermediate cardiac troponin concentrations can improve the use of preventative medical therapies and clinical outcomes. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The British Heart Foundation Odds ratio of coronary artery diseaseCumulative proportion with CAD

This paper examines Korea's answer to the rural development challenge in the 1970s, the Saema��l Undong movement (SMU). As one of the revolutionary polices of Park Chung-Hee, it has been highlighted as contributing greatly to the South Korean economic miracle. There is consensus that it is a shining example of a successful rural development policy and has been widely documented. Given the signal achievements of the programme, this paper attempts to establish whether the SMU could be useful for Ghana as a lasting solution to rural underdevelopment. This paper presents a critical historical background of the SMU and how it was executed highlighting in particular the factors that were crucial to the success of the initiative. The Korean explications are then set against an overview of Ghana's attempts at rural development in an attempt to account for the reasons why Ghana has not been as successful at this task. Our conclusion is that the SMU can serve as a repository of best practices and outline lessons therefrom to guide the formulation and implementation of an integrated, home-grown rural development strategy to ensure the best possible chance of success of such a strategy.The publisher's final version of this work can be found at https://doi.org/10.1163/15692108-12341417. Deposited by shareyourpaper.org and openaccessbutton.org. We've taken reasonable steps to ensure this content doesn't violate copyright. However, if you think it does you can request a takedown by emailing help@openaccessbutton.org.

Aims To determine the reproducibility of flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) in the assessment of radial artery vasomotor function, and to examine the effect of transradial catheterisation on radial artery injury and recovery. Methods Radial artery FMD and NMD were examined in 20 volunteers and 20 patients on four occasions (two visits at least 24 hours apart, with two assessments at each visit). In a further 10 patients, radial artery FMD was assessed in the catheterised arm prior to, at 24 hours and 3 months following cardiac catheterisation. Results There were no differences in baseline radial artery diameter (2.7±0.4 mm vs 2.7±0.4 mm), FMD (13.4±6.4 vs 12.89±5.5%) or NMD (13.6±3.8% vs 10.1±4.3%) between healthy volunteers and patients (p>0.05 for all comparisons). Mean differences for within and between day FMD were 2.53% (95% CIs −15.5% to 20.5%) and −4.3% (−18.3% to 9.7%) in patients. Compared to baseline, radial artery FMD was impaired at 24 hours (8.7±4.1% vs 3.9±2.9%, p=0.015) but not 3 months (8.7±4.1% vs 6.2±4.4, p=0.34) following transradial catheterisation. Conclusions Radial FMD is impaired early after transradial catheterisation but appears to recover by 3 months. While test–retest variability was demonstrated, our findings suggest that transradial access for cardiac catheterisation may afford a potential model of vascular injury and repair in vivo in man.

Methodologies are presented which can greatly aid in the site selection decision process. The site selection process is viewed as being composed of two major stages or phases. Phase I involves the application of quantitative models to identify potential locations. The results obtained from such models provide numerically optimal solutions, which can then be used to help identify feasible candidate sites. After identifying a set of candidate sites, additional factors, qualitative as well as quantitative, can be evaluated through the application of a multi-criteria decision model (Phase II). Prior to the implementation of Phase I, the solution space for the problem can be narrowed through selective screening or pruning to reduce the number of potential sites to a realistic set. During the analysis phases, one alternative may prove to be equal to the others in all respects and better in at least one aspect. This alternative is then said to dominate the others, and the analysis ends with its selection. >

The aim of the study was to examine the effects of the ETB receptor selective agonists sarafotoxin S6c (SFTX6c) and BQ-3020 on the forearm resistance and capacitance vessels in healthy subjects in vivo.The local response to intra-arterial or intravenous infusion of SFTX6c (5 pmol min-1) or BQ-3020 (50 pmol min-1) was assessed, on separate occasions, in eight healthy men (aged 20-28 years). Data (mean +/- s.e.mean) were examined by ANOVA. Results are expressed as percentage change from baseline at 90 min.SFTX6c and BQ-3020 reduced forearm blood flow, following local intra-arterial infusion (-25 +/- 7% and -27 +/- 7%, respectively; P0.001) and reduced hand vein diameter, following local intravenous infusion (-30 +/- 8% and -16 +/- 7%, respectively; P0.001).We have shown that locally active infusions of the selective ETB receptor agonists SFTX6c and BQ-3020 cause arterial constriction and venoconstriction in healthy human blood vessels in vivo. These results indicate that ETB receptor stimulation may mediate vasoconstriction in humans.

The permanent loss of erectile function when both neurovascular bundles are widely resected at radical prostatectomy as well as the successful use of autologous nerve grafts in reconstructive surgery led us to perform bilateral nerve grafts in an effort to restore erectile function in potent patients treated for prostate cancer who underwent radical retropubic prostatectomy and resection of both neurovascular bundles.Radical retropubic prostatectomy with deliberate resection of both neurovascular bundles was recommended for high grade, locally extensive prostate cancer in 9 select, sexually active men who reported normal erectile function. After the prostate was removed but before vesicourethral anastomosis an autologous sural nerve graft was interposed between the divided ends of the cavernous nerves bilaterally. Erectile function was monitored by patient interview, questionnaire and nocturnal penile tumescence testing after the operation.Four to 5 months postoperatively patients noticed slowly improving spontaneous erections, as manifested by mild tumescence regularly every several hours. Nocturnal penile tumescence testing with the RigiScan device at 4 to 6 months in 2 cases revealed erections that approached minimal criteria for normalcy. Approximately 14 months after surgery a rigid erection sufficient for penetration and intercourse developed in 1 patient. He described this event as "an erection of substance-hard, not just fluffy."We have developed a technique using sural nerve grafts to restore continuity of the cavernous nerves, which are resected during radical prostatectomy. The early return of spontaneous partial erections in our patients suggests that interposition nerve grafts may enhance the recovery of erectile function when the neurovascular bundles are resected.

Questions remain concerning the physiologic capabilities of the right gastroepiploic artery as a bypass graft in the clinical setting. Our last 90 consecutive pedicle right gastroepiploic artery grafts were prepared with intraluminal papaverine and verapamil. Our series comprised 81 male and 9 female patients with average body surface areas of 1.92 m2. Ages ranged from 11 to 79 years (mean 57.2 years). A second to fourth revascularization was undertaken in 32 patients (35.5%). The following arteries were bypassed: posterior descending artery, 63; right coronary artery, 23; distal right, 4; circumflex, 2; left anterior descending, 1; and diagonal, 1. Free flow rates ranged from 42 to 660 ml/min (mean 179.96 ml/min). Internal diameters measured 1.5 to 4.0 mm (mean 2.20 mm) at the anastomotic sites. Pedicle lengths ranged from 16 to 26 cm (mean 19.2 cm). Inotropic support was required in 11 patients (12%) and had no adverse effects on right gastroepiploic artery grafts. There were 2 hospital deaths (2.2%). Angina has recurred in 6 patients. One patient with cardiomyopathy required transplantation 2 years after coronary bypass grafting. Repeat angiography showed widely patent grafts in 18 patients and generalized narrowing in 4 grafts. In only 2 patients of our total experience has right gastroepiploic artery grafting been aborted because of inadequate conduit size. One right gastroepiploic artery had visible atherosclerosis. This study shows that distal right gastroepiploic artery sizes are comparable with sizes of target coronary arteries. However, neither flow nor size is as consistent when compared with internal thoracic artery grafts. Higher flow rates are related to graft anatomic characteristics and larger body surface areas. Spasm, secondary to harvest in these vasoreactive grafts, can be managed appropriately by intraluminal vasodilating drugs. However, use of the right gastroepiploic artery should be avoided in a setting with possible competition of flow.

This paper describes our experience in performing saphenous vein bypass grafts to the circumflex coronary artery system with a left thoracotomy in 9 patients. Illustrative case reports demonstrate the spectrum of patients for whom this approach has been useful. The advantage of this technique is that it allows the surgeon to avoid the adhesions that make a redo sternotomy time-consuming and potentially dangerous when previously patent saphenous vein or internal mammary grafts are present. It is particularly useful for patients requiring grafting to the circumflex coronary artery system, especially if the patient is in relatively unstable condition and would benefit from rapid institution of cardiopulmonary bypass. The technique generally employs cannulation of the descending thoracic aorta for arterial inflow and of the main pulmonary artery for venous return. Usually the proximal end of the graft is easily placed to the left subclavian artery. Coronary anastomosis is performed on the cold (15 degrees C), fibrillating heart, and aortic cross-clamping and cardioplegic arrest have not been necessary. Venting is possible through the left atrial appendage should any rise in filling pressures occur. Saphenous vein or internal mammary artery may be used. All patients undergoing this technique have had expeditious discharge from the hospital and excellent relief of symptoms. The technique is an alternative to median sternotomy for properly selected patients.

Analysis of 1735 patients who underwent coronary artery bypass grafting from January 1981 through December 1988 revealed 152 (8.8%) patients with mild (4.5%), moderate (2.2%), or severe (2.0%) atherosclerosis of the ascending aorta. Three distinct pathologic patterns were found. The prevalence of stroke in patients with the severe type of aortic disease prompted development of a new operative technique that has been used in 16 patients. It involves a "no-touch" technique of the ascending aorta whereupon the proximal saphenous vein anastomoses are performed end to side to internal mammary artery grafts. Ages ranged from 49 to 80 years (mean 68.9). The 16 patients had 62 distal artery and vein anastomoses and 26 proximal saphenous vein-internal mammary end-to-side anastomoses. Internal mammary artery free flows ranged from 130 to 420 ml/min. Two hospital deaths were unrelated to the technique. There have been no strokes or recurrences of angina. An inordinately high incidence of main left coronary disease (50%), significant carotid disease (79%), and abdominal aortic occlusive or aneurysm disease (93%) was discovered. Ascending aortic atherosclerosis must be suspected in all coronary bypass patients with associated significant carotid, abdominal aortic, and main left coronary artery disease, aortic wall irregularity on ascending aortic angiography, adhesions between the ascending aorta and its adventitia, pale appearance of the ascending aorta, and minimal bleeding of an aortic cannulation stab wound. A "no-touch" technique that avoids any manipulation of the ascending aorta and that uses the internal mammary arteries as the sole source of blood supply for coronary bypass is an effective method to prevent aortic clamp injury, "trash heart," or stroke from severe ascending aortic disease. Preoperative angiographic visualization of the ascending aorta of all patients undergoing coronary artery bypass is mandatory.

Recent trends in the patient population coming for surgical treatment of coronary artery disease have prompted alterations in the type of coronary artery bypass surgery performed. Emphasis is placed on the more widespread use of arterial grafts and revascularization of vessels with extensive distal disease, utilizing endarterectomy techniques, in an attempt to provide a more complete and long-lasting revascularization.

This paper presents a network-based simulation model for the microcomputer to solve the resource balancing problem. The specific application discussed is systems planning for Motor Vehicles operations; however, the approach is adaptable to many organizations. The developed software is an interactive concept program, and can be used by people with no experience in computer programming.

This paper presents a summary of the methodology employed in investigating the economic feasibility of constructing small (10 MW e ) biomass-fueled electric generating plants, specifically, the development of an interactive computer program designed for the calculation of levelized bus bar power costs and the application of this program to perform economic sensitivity analyses.

The development of a university sports complex requires an integrated planning, scheduling and management approach, a requirement which is underscored by the desired to overlap design and construction activities in order to complete the facility on an accelerated schedule. The analysis of the project utilizes project management techniques: development of network models, identification of critical paths, and scheduling, cost control and resource allocation considerations. The use of computerized project planning and control tools provides flexibility and enables easy modification of the plans.

Eighty-one consecutive patients with distal multivessel coronary artery disease underwent 93 attempts at operative transluminal angioplasty at the time of coronary bypass operation. Lesions chosen for angioplasty were those in coronary arteries that otherwise would not have been bypassed because of small size and/or inaccessible location; 53% involved the distal anterior descending artery. A guide wire-tipped catheter with a 2 mm balloon was found to be the more satisfactory of the two devices used. An operative "successful" dilatation was achieved with 75 lesions (81%). Eighteen "unsuccessful" dilatations occurred primarily because of inability to transverse the lesions with the catheter. Postoperative angiography was performed in 29 patients to study 31 lesions. In 20 of 28 "successfully" dilated lesions (71%), the stenoses were completely alleviated. Three lesions were found unimproved and in two lesions, the coronary arteries were occluded distally. Two bypass grafts, involving two lesions with extensive dilatation, were closed. Two patients had definite perioperative myocardial infarction, and there were no deaths in this series. Whereas calcification did not influence success, the length of the lesion was inversely proportional to a successful dilatation. Operative dilatation of short coronary distal lesions is safe, has a high percentage of success, and offers a larger distal runoff for coronary bypass grafts. Areas of normal coronary arteries should not be dilated. Careful attention to detail and proper selection of the lesions to be dilated are required. The technique should be used only to dilate arteries that otherwise would not accept a bypass graft.

From January, 1971, through May, 1978, the records of 1,239 patients who had comparable patterns of coronary artery bypasses were retrieved for study from the Ochsner computerized data bank. Seven hundred twenty-six patients had saphenous vein grafts (SVG) alone and 513 patients had internal mammary artery (IMA) grafts alone or in combination with SVG. Patients with IMA grafts had significantly improved survival over patients with SVGs, but after exclusion of biasing subgroups the improved survival was not reliably different (p = 0.1684). The percentages of patients who had unrelieved angina after operation were similar (5.0% versus 4.8%); the rates of nonfatal myocardial infarction and of postoperative congestive heart failure were also similar. When the recently done SVG bypasses were compared to those done before mid-1975, we found that unrelieved angina rates and nonfatal myocardial infarction rates were significantly improved in the recent group. We conclude that use of the SVG is indicated in some clinical situations and use of the IMA graft in others. Therefore, cardiovascular surgeons should be proficient in using both grafts.

This report described a case in which purulent mediastinitis involving a Hancock prosthesis developed after repair of truncus arteriosus in a 6-year-old boy. The graft and surrounding area became sterilized after having been irrigated with povidone-iodine and antibiotic solutions for 6 weeks. At his most recent visit, the child was completely active and asymptomatic.

A patient had unilateral renal artery stenosis and, at the same time, bilateral polycystic kidney disease. The renal venous renin ratio of 151:40, together with a high peripheral plasma renin activity, indicated that the hypertension was partially caused by renopressor mechanism. Correction of the obstructive lesion permitted a better control of hypertension with antihypertensive drugs, and the peripheral and renal venous renin activity returned to normal. The success in detecting one pathogenic mechanism responsible for arterial hypertension should not deter further diagnostic efforts.

Early reports questioned the adequacy of flow of the internal mammary artery when used routinely as a bypass graft. "Adequate" mammary artery flow is now contested only in certain situations, that is, left ventricular hypertrophy, acute myocardial infarction, and reoperations. To compare the methods of mammary pedicle graft preparations with free mammary artery flow, we studied 31 patients who had the left internal mammary artery harvested for elective coronary artery bypass grafting. Group I comprised 14 patients whose mean body surface area was 1.91 m2. Systolic, diastolic, and mean arterial blood pressures, left atrial pressure, and heart rate were recorded and stabilized during flow measurements. Free flow of the internal mammary artery was measured before any pharmacologic manipulation and ranged from 5 to 44 ml/min (mean 18 ml/min). The grafts were sprayed and wrapped in sponges soaked in diluted papaverine solution (60 mg in 40 ml normal saline) for an average of 21 minutes. Free flow ranged from 10 to 108 ml/min (mean 51 ml/min). Intraluminal papaverine of the same dilution was then injected with hydrostatic dilatation. Immediate internal mammary artery flows rose from 150 to 333 ml/min (mean 229 ml/min). Group II comprised 17 patients who had internal mammary artery takedown under the exact conditions used in group I. Mean body surface area was 1.89 m2. Mammary artery pedicles were injected with diluted papaverine throughout their lengths with size 25 needles. After an average of 19.5 minutes, free flow ranged from 28 to 132 ml/min (mean 69 ml/min). Intraluminal diluted papaverine was then administered as in group I, and flows increased from 144 to 280 ml/min (mean 198 ml/min). The distal internal mammary arteries in both groups were 1.75 to 2.5 mm in internal diameter at the site of arteriotomy for flow measurement. This study shows that all mammary arteries are in spasm immediately after harvest and that flow is inadequate before any pharmacologic intervention. Although extraluminal vasodilators will increase free mammary artery flow, intraluminal papaverine followed by hydrostatic dilatation raises free flow to maximal capacity. Subsequent graft spasm has not been observed.(ABSTRACT TRUNCATED AT 400 WORDS)

We report the management and evaluation of three difficult left ventricular aneurysms from a series of 246 cases treated between 1970 and 1985. These three cases reflect our present approach to left ventricular aneurysms after previous aortocoronary bypass (case 1), aneurysms with distorted ventricular geometry and severe mitral regurgitation (case 2), and large, minimally symptomatic left ventricular aneurysms (case 3). All three cases had very little or no coronary artery disease, and the main purpose of surgery in them was primarily to correct ventricular pathology.

By careful evaluation of the sonographic characteristics of carotid plaques, two patterns can be identified: (1) a homogeneous pattern containing uniform echoes corresponding to dense fibrous tissue and (2) a heterogeneous pattern containing mixed echoes and anechoic areas that represent intraplaque hemorrhage pathologically. A prospective study was conducted of 50 patients to determine the accuracy of identifying these different forms of plaque. The patients' carotid arteries were examined by a high-resolution duplex scanner before carotid endarterectomy. The plaques were evaluated carefully by vascular surgeons and pathologists for the presence of intraplaque hemorrhage. In this study, the accuracy of identifying the presence or absence of intraplaque hemorrhage with sonography was 90% (48 of 54); sensitivity, 94% (17 of 18); and specificity, 88% (27 of 31). High-resolution sonography appears to be an accurate means of identifying intraplaque hemorrhage and may ultimately be useful in identifying patients at risk for embolic disease.

A 17-year-old girl had clinical and cardiac catheterization findings compatible with a secundum atrial septal defect. During cardiac catheterization, the atrial septal defect was sized and closed using a transvenous umbrella technique.

In a study of the initial 1,004 consecutive patients who had direct coronary artery bypass at Ochsner Medical Institutions, computer methods of data processing were used to compare the clinical results between patients who had saphenous vein (SV) grafts and those who had internal mammary artery (IMA) grafts. The factors compared were the long-term mortality rates, nonfatal myocardial infarction rates, relief or persistence of angina, and the percentage of patients who acquired congestive heart failure. A simple comparison showed the patients with IMA grafts did better in all four categories; however, in a subsequent analysis in which maldistributed factors were removed, the rates of anginal relief and congestive heart failure were not significantly improved. The major benefit appears to be an increase in longevity among patients who had IMA bypasses.

Since a 1974 report of nonoperative closure of atrial septal defects (ASDs) using an umbrella catheter device, an additional 25 dogs have undergone creation of atrial septal defects, 12 of which have subsequently had successful transvenous closure. An improved model of the closure device has been developed, still using a pair of interlocking umbrella-like components made of stainless steel and Dacron. The umbrellas are smaller, lighter, and have an automatic opening ring. They are loaded simultaneously into a single capsule on the distal end of the outer catheter and are passed into the heart on a single passage, thus eliminating several steps of the original technique. Closure time has diminished from an average of 30 minutes to 5-10 minutes. The completeness of closure was documented in 12 animals by repeat cardiac catheterization which included hydrogen electrode studies. Autopsies on 10 sacrificed dogs revealed no adverse effects or migration of the device; two dogs are living and healthy. In the one clinical application, the patient has done well, remaining afebrile with an increased activity tolerance and resumption of normal activities. The umbrella has remained in position and appears to be functioning well.

Case histories of 8 consecutive patients who underwent surgical correction of Type C complete atrioventricular (A-V) canal at the Ochsner Medical Center over the past 2 years were analyzed. Ages ranged from 1 1/3 to 14 years. Before bypass, the level to which the common leaflets ascend and the arc that they inscribe are determined by palpation to ensure their proper reconstitution on the canal patch. The major area of closure is usually allocated to the ventricular portion. Mapping the conduction system and tying sutures with the heart beating in high-risk conduction areas prevent heart block. Precise marking and splitting of the valve leaflets and reattachment with interrupted felt-buttressed sutures avoid disruption. All patients survived the operation and have shown clinical improvement. At recatheterization, 7 of 8 patients have shown a definite decrease in mitral insufficiency. Right ventricular pressures returned toward normal and there were no significant residual shunts. Associated anomalies or previous operations have not been a contraindication, and since we have begun using the present technique, we have achieved consistently good results without prosthetic valves.

Massive air embolism during cardiopulmonary bypass is a frightening complication requiring immediate response and carrying strong medicolegal implications. From July, 1971, to July, 1979, there were eight instances of massive air embolism during 3,620 cardiopulmonary bypass operations. Five such accidents from other institutions are included in this report. Causes were (1) inattention to reservoir level, (2) reversal of pump head tubing or direction of pump head rotation, (3) unexpected resumption of heartbeat, (4) inadequate steps to remove air after cardiotomy, (5) high-flow suction deep in a pulmonary artery, (6) defective oxygenator, (7) use of a pressurized cardiotomy reservoir, and (8) inadvertent detachment of oxygenator during bypass. Prevention includes a systematic check of pump suckers and perfusion lines before bypass, a sensing device on the oxygenator reservoir, secure fixation of the oxygenator and avoidance of traffic around pump equipment, immediate cessation of pump and inspection for abnormal noise, use of standard maneuvers to remove air from the heart, and carotid compression with resumption of heartbeat. Immediate management of massive air embolism consists of placing the patient in a deep Trendelenburg position and making a large stab wound in the ascending aorta for retrograde drainage from the cerebrovascular bed. Temporary retrograde perfusion through the superior vena cava (SVC) may also be used. Subsequent steps are hypothermia with the resumption of cardiopulmonary bypass, elevation of blood pressure, steroids, ventilation with 100% oxygen, and deep barbiturate anesthesia. Among the 13 patients, there were four instantaneous deaths. Cerebral injury which resolved within a 2 month period occurred in three patients. The remainder had no neurologic sequelae. Nonfatal cerebral air injury may be associated with prolonged convalescence yet complete recovery, as compared to embolism from debris or clot, which offers a poorer prognosis.

A case if reported of a 2 1/2-year-old boy with an extensive filtration of the retroperitoneum, mediastinum, and almost every organ of the body with a very primitive type of tumor identified as a poorly-differentiated mixed histiocyticlymphocytic lymphoma. The right atrium was completely filled with a large intracavitary metastasis which caused obstruction of the venous return to the heart with subsequent death.

Two patients referred to Ochsner Foundation Hospital after ventricular aneurysm repair had the delayed pulmonary complications of massive hemoptysis and bronchiectasis. Only three cases of infected ventricular aneurysm repair have been reported previously. The felt buttress used in aneurysm repair may be the seat of indolent infection or it may erode into pulmonary tissue with secondary infection. For anatomic reasons the lingular segment of the lung appears to be at increased risk of involvement. Symptoms led to the correct diagnosis in one case at 7 months and in the other at 3 years after the original operation. Infection may be prevented by appropriate measures. However, should such a catastrophe occur, aggressive surgical therapy with removal of all foreign material is mandatory.

Efforts to close left-to-right shunts at Ochsner Medical Institutions have been directed toward atrial septal defects (ASD) and patent ductus arteriosus (PDA). PDA's were constructed in dogs by interposing a segment of jugular vein between the aorta and main pulmonary artery. Five dogs in which the PDA was closed by a plug device inserted through the femoral vessels were put to death at 6 to 12 months. Histologic sections showed good fibrous ingrowth with endothelial covering on the aorta and pulmonary artery sides. There were no migrations redidual shunts. At cardiac catherterization, 18 patients had ASD's sized and located as to position in the septum. The sized ranged from 13 to greater than 30 mm. in diameter. The ASD sizes in patients who underwent standard operative closure were compared to the measurements at catheterization, and the variation was insignificant. In 5 patients, centrally positioned secundum ASD's were closed with double umbrella devices, 25 to 35 mm. in diameter. Anatomic contraindications for umbrella closure include ASD's greater than 30mm. in diameter, anomalous pulmonary venous connection, common atrium, inferiorly or superioly located secrumdum ASD, and sinus venosus ASD. Follow-up studies from 6 to 12 months on 5 patients with umbrella closure have revealed no hemolysis, arrhythmias, thromboembolism, migration, or other untoward effects.