27 results on '"C Tiefenbacher"'
Search Results
2. Kommentar zu den Leitlinien (2017) der ESC zu peripheren arteriellen Erkrankungen
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R. Zahn, Christine Espinola-Klein, C. Heiß, C. Tiefenbacher, and J. B. Dahm
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Gynecology ,03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,business.industry ,Medicine ,030212 general & internal medicine ,030204 cardiovascular system & hematology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Die 2017 veroffentlichte „European Society of Cardiology“(ESC)-Leitlinie „Periphere Arterielle Erkrankungen“ (PAE, „peripheral arterial diseases“) umfasst Empfehlungen zur Diagnostik und Therapie von atherosklerotischen Manifestationen in peripheren Gefasen. Es werden zu allen arteriellen Versorgungsgebieten mit Ausnahme der Aorta und Koronararterien Empfehlungen formuliert. Der folgende Kommentar bezieht sich auf die Ubersetzung der Pocket-Leitlinie und ist fokussiert auf die Empfehlungen zur Sekundarpravention, zur peripheren arteriellen Verschlusskrankheit (pAVK) und zur Karotisstenose. In den Empfehlungen zur Sekundarpravention wird die Atherosklerose als Erkrankung des gesamten Gefassystems betrachtet. Generell wird eine konsequente Einstellung der kardiovaskularen Risikofaktoren mit absoluter Rauchkarenz, dem Einsatz von Statinen sowie einer Blutdruck- und Blutzuckerkontrolle empfohlen. Patienten mit Claudicatio intermittens sollten moglichst ein supervidiertes Gehtraining betreiben. Ein Thrombozytenaggregationshemmer sollte gegeben werden, wenn eine symptomatische pAVK vorliegt oder bei weiteren Manifestationen der Atherosklerose wie beispielsweise einer koronaren Herzerkrankung (KHK). Liegt eine starke Einschrankung im Alltag vor, wird eine Revaskularisation empfohlen. Bei Vorliegen einer Indikation zur Revaskularisation sollte bei kurzen Gefasverschlussen (z. B.
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- 2018
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3. PEACE Register – 12 Monatsdaten – Pulsar Efficacy: an All Comers Registry
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C Tiefenbacher, M Lichtenberg, B Hailer, G Wittenberg, J Arjumand, and C Nolte-Ernsting
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Pulsar ,Register (music) ,business.industry ,Medicine ,Radiology, Nuclear Medicine and imaging ,Medical emergency ,business ,medicine.disease - Published
- 2014
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4. Preservation of myocardial blood flow by calcium antagonists does not prevent attenuation of regional myocardial function after repetitive brief periods of myocardial ischaemia in the rat heart
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Rainer Zimmermann, Bernhard H. Rauch, Kübler W, N. Parekh, K. Amann, C. Tiefenbacher, and Harald Tillmanns
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Gallopamil ,Nifedipine ,Myocardial Ischemia ,Ischemia ,Rats, Inbred WF ,Hemodynamics ,Reperfusion therapy ,Animals ,Medicine ,cardiovascular diseases ,Infusions, Intravenous ,Myocardial stunning ,business.industry ,Blood flow ,Calcium Channel Blockers ,medicine.disease ,Rats ,Anesthesia ,Female ,Cardiology and Cardiovascular Medicine ,business ,Perfusion ,Blood Flow Velocity ,medicine.drug - Abstract
The aim of this study was to assess the effect of two different calcium channel blockers on myocardial blood flow and function in a rat model of myocardial 'stunning' by repeated short episodes of ischaemia ('repetitive ischaemia'). In an open chest rat model, the left anterior descending coronary artery was ligated for 10 min followed by 15 min reperfusion. In total, five periods of ischaemia and reperfusion were performed. Myocardial blood flow was assessed by the hydrogen clearance technique and systolic thickening fraction by pulsed Doppler. After five episodes of ischaemia, myocardial blood flow adn myocardial thickening in the ischaemic area were reduced by 60 +/- 8% and 52 +/- 7% (n=9), respectively, as compared to baseline. Continuous intravenous infusion of the calcium channel blockers nifedipine (n=6) and gallopamil (n=6), started 20 min prior to onset of ischaemia, attenuated the ischaemia-induced decrease of myocardial perfusion. Nifedipine was the most effective with only 5 +/- 2% reduction in blood flow after five ischaemic episodes, whereas reduction of myocardial blood flow was 30 +/- 4% in the presence of gallopamil. However, neither nifedipine nor gallopamil were able to prevent regional ventricular dysfunction induced by repetitive ischaemia. Despite the preservation of myocardial blood flow following repetitive ischaemia, calcium channel blockers do not prevent ischaemia-induced reduction of myocardial function in the ischaemic area.
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- 1995
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5. [Curriculum for interventional therapy for arterial diseases. Clinical competence for execution of catheter-based interventions on the arteries of the extremities, on the pelvic, visceral and renal arteries, on the extracranial arteries supplying the brain, and on dialysis shunts]
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K-L, Schulte, K, Amendt, U, Hoffmann, C, Tiefenbacher, T, Weiss, H, Mudra, D, Hardung, and S, Nikol
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Peripheral Arterial Disease ,Certification ,Consensus ,Education, Medical, Graduate ,Germany ,Catheterization, Peripheral ,Endovascular Procedures ,Humans ,Clinical Competence ,Competency-Based Education - Published
- 2012
6. [European guidelines on myocardial revascularization]
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Stefan M, Perings, R, Bosch, T, Eggeling, M, Hennersdorf, K, Graf La Rosee, T, Korte, T, Lauer, M, Leschke, T, Lewalter, D, Mathey, H, Mudra, N, Reifert, K, Rybak, H, Sievert, and C, Tiefenbacher
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Europe ,Practice Guidelines as Topic ,Cardiology ,Myocardial Revascularization ,Humans ,Coronary Artery Disease - Published
- 2011
7. Europäische Leitlinien zur Myokard-Revaskularisation
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C Tiefenbacher, Stefan M Perings, Thorsten Lewalter, Thomas Lauer, K Graf La Rosee, N Reifert, D Mathey, Harald Mudra, M Leschke, T Korte, T Eggeling, M. Hennersdorf, R Bosch, K. Rybak, and Horst Sievert
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medicine.medical_specialty ,Myocardial revascularization ,business.industry ,Internal medicine ,Cardiology ,MEDLINE ,Medicine ,Cardiology and Cardiovascular Medicine ,business - Published
- 2011
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8. Activation of neutrophils in the microvasculature of the ischaemic and reperfused myocardium
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H, Tillmanns, F J, Neumann, C, Tiefenbacher, O, Dorigo, N, Parekh, W, Waas, R, Zimmermann, M, Steinhausen, and W, Kuebler
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Myocardial Stunning ,Nifedipine ,Neutrophils ,Microcirculation ,Coronary Vessels ,Rats ,Capillary Permeability ,Coronary Circulation ,Cell Adhesion ,Leukocytes ,Animals ,Humans ,Angioplasty, Balloon, Coronary ,Blood Flow Velocity - Abstract
In 11 rats, the microcirculation of the repeatedly ischaemic (stunned) left ventricular myocardium was studied using in vivo fluorescence microscopy. Stunning was provoked by six subsequent 10 min ligations of the left anterior descending coronary artery, each of them followed by a 20 min reperfusion period. In the stunned myocardium showing hypokinetic wall motion, myocardial blood flow dropped by 55%; in this region, leukocytes often appeared in slow-flow capillaries plugging capillary branches. Closely linking to leukocyte adherence, a rise of microvascular permeability was documented by extravascular clouds of fluorescent dextran. After nifedipine treatment, in ischaemic regions marked dilatation of larger A1 and A2 arterioles was noted, in addition to the ischaemia-induced dilatation of smaller A3 and A4 arterioles. Furthermore nifedipine and nisoldipine reduced the number of adherent leukocytes in post-capillary venules and capillaries of the repeatedly ischaemic myocardium. In 12 patients with coronary one-vessel disease and without previous transmural myocardial infarction, elective coronary angioplasty (PTCA) was performed (balloon inflation for 2 min). After elective PTCA of the LAD, a significant rise in the proportion of activated neutrophils was noted. After elective 2 min PTCA of the LAD, coronary sinus blood samples showed a marked rise of FMLC stimulated superoxide anion production, whereas passive deformability decreased considerably. Furthermore, an increase in chemotactic activity in coronary sinus blood samples was observed.
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- 1993
9. Pharmacologic effects on coronary microvessels during myocardial ischaemia
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M. Steinhausen, C. Tiefenbacher, O. Dorigo, W. Kübler, Harald Tillmanns, N. Parekh, F. J. Neumann, and Zimmermann R
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medicine.medical_specialty ,Myocardial ischaemia ,Myocardial ischemia ,Indomethacin ,Coronary Disease ,Capillary Permeability ,Internal medicine ,Coronary Circulation ,Pharmacologic effects ,Medicine ,Animals ,Gallopamil ,business.industry ,Platelet Count ,Microcirculation ,Fatty Acids ,Imidazoles ,Coronary Vessels ,Rats ,Verapamil ,Cardiology ,Erythrocyte Count ,Thromboxane-A Synthase ,Cardiology and Cardiovascular Medicine ,business ,Blood Flow Velocity - Published
- 1990
10. Microcirculation in the hypertrophic and ischemic heart
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F. J. Neumann, Harald Tillmanns, Oliver Dorigo, C. Tiefenbacher, Rainer Zimmermann, Niranjan Parekh, Michael Steinhausen, and Wolfgang Kübler
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medicine.medical_specialty ,Ischemia ,Hemodynamics ,Vascular permeability ,Cardiomegaly ,Coronary Disease ,Myocardial Reperfusion ,Left ventricular hypertrophy ,Microcirculation ,Internal medicine ,medicine ,Animals ,Pharmacology (medical) ,cardiovascular diseases ,Pharmacology ,business.industry ,General Medicine ,Blood flow ,medicine.disease ,Coronary Vessels ,Hypertensive heart disease ,Capillaries ,Rats ,Blood pressure ,Microscopy, Fluorescence ,Hypertension ,Cardiology ,business ,Blood Flow Velocity - Abstract
I. Myocardial hypertrophy, for instance in patients with hypertensive heart disease, is characterized by a reduction of coronary vascular reserve, even in the presence of normal coronary arteries. In hypertensive animals, on the microcirculatory level functional changes can be observed before the onset of any structural rarefications. In 10 rats with renal hypertension and pressure-induced left ventricular hypertrophy (LVH), the microcirulation of the left ventricular myocardium was studied using in vivo fluorescence microscopy and morphometric analysis. Renal hypertension was provoked by clipping of the left renal artery. After 8 weeks, systolic blood pressure in LVH rats averaged 172 ± 8 mm Hg, compared to 91 ± 2 mmHg in 10 normotensive (NT) rats. In LVH rats, distances of plasma-perfused capillaries were significantly increased (NT = 17.7; LVH = 20 μm;p < 0.001). Volume density, surface density, and length density of capillaries in LVH rats were reduced by 20% compared to NT rats. Capillary red cell content as measured by the ratio of capillaries filled with red cells to those containing plasma alone (Q) in LVH animals exceeded that in NT rats (LVH: Q = 0.83 ± 0.04; NT Q = 0.77 ± 0.04;p < 0.025). During hypoxia (H, 5% 02) capillary red cell recruitment in LVH rats (Q: control c = 0.83; H = 0.95) was diminished by 33% as compared to NT rats (Q: c = 0.77; H = 0.95). Thus, in addition to the decreased capillary density, the reduction of capillary red cell recruitment may be responsible for chest pain in patients with LVH and normal coronary arteries. 2. In 11 rats, the microcirculation of the repeatedly ischemic (stunned) left ventricular myocardium (SM) was studied using in vivo fluorescence microscopy. Stunning was provoked by 6 subsequent 10 minute ligations of the left anterior descending coronary artery, each of them followed by a 20 min reperfusion period. In the SM showing hypokinetic wall motion mean capillary blood flow velocity was markedly reduced (control c =1312; SM = 694 μm/sec;p < 0.001): myocardial blood flow (hydrogen clearance) in the SM dropped by 55%. In SM, leukocytes often appeared in slow-flow capillaries plugging capillary branches: the percentage of capillaries and postcapillary venules with adherent leukocytes was markedly increased (c = 3%; SM = 68%). In close link to leukocyte adherence, a rise of microvascular permeability was documented by extravascular clouds of fluorescent dextran. The ratio of capillaries filled with red cells to those containing plasma alone was diminished in SM (c = 0.77; SM = 0.65;p < 0.001). In the SM there are microcirculatory disturbances which occur before the onset of detectable structural alterations of both the microvasculature and the myocyte.
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- 1990
11. Gender and career in cardiology-a cross-sectional study.
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Dettmer S, Wenzel A, Trenkwalder T, Tiefenbacher C, and Regitz-Zagrosek V
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- Cross-Sectional Studies, Employment, Female, Humans, Male, Surveys and Questionnaires, Cardiology, Physicians, Women
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Background: The proportion of women as leading physicians in cardiology in university medicine has stagnated and the share of women in senior positions in cardiology is low compared with other medical specialist fields. Here, we analyze the typical barriers for women as doctors in cardiology and point to issues that make the discipline less attractive for both genders., Methods: In a cross-sectional study, a standardized online questionnaire was sent to 3873 members of the German Cardiac Society (DGK). Answers from 567 (278 women, 289 men) were analyzed, using comparisons between groups, correlation analyses, and tests of normal distribution., Results: For 47.4% of respondents (52.0%, of women; 42.8%, of men; p = 0.049), training had lasted longer than anticipated. Average monthly gross income (full-time work) differed significantly between women and men as specialists (p = 0.004) and assistant doctors (p = 0.030). Of women, 32.1% had experienced sexual harassment in the workplace. The main arguments against a career in university medicine were an extremely competitive working climate (66.7% of women, 63.2% of men), lack of work-life balance (66.7% women, 55.3% men), and excessive workload (57.8% women, 62.5% men). As strategies to increase job attractiveness, both mentioned measures to improve the work-life balance, and the flexibility of working times and improved financial provision. Women asked for gender balance at management level (76.3% vs. 32.9% of men) and opportunities for sharing management tasks (82.4% vs. 57.9%). Flatter hierarchies were requested by more men (67.1 vs. 54.8%)., Conclusion: Further development of the work culture in cardiology seems necessary. In order to increase the attractiveness of the field overall and to provide equal opportunities in cardiology, more targeted support should be provided to young doctors and more flexibility introduced into work.
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- 2021
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12. Real-world outcomes of endovascular treatment in a non-selected population with peripheral artery disease - prospective study with 2-year follow-up.
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Schulte KL, Hardung D, Tiefenbacher C, Weiss T, Hoffmann U, Amendt K, Tepe G, Heuser L, Treszl A, Lau HJ, Pfannebecker T, and Wegscheider K
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- Female, Femoral Artery, Follow-Up Studies, Humans, Male, Popliteal Artery, Prospective Studies, Quality of Life, Stents, Treatment Outcome, Vascular Patency, Angioplasty, Balloon, Peripheral Arterial Disease
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Background: The study aimed to evaluate the outcomes of percutaneous transluminal angioplasty (PTA) in lower-extremity peripheral artery disease (PAD) patients. Patients and methods: A multi-centre, observational study was performed with 32 German and Austrian centres contributing data to the PTA registry. Data of 1,781 patients with lower-leg and pelvic PAD who were suitable for endovascular PTA treatment were contributed from participating centres. Data from 1,533 patients are reported here (1,055 male and 478 female). This study did not have exclusion criteria. Quality of life (QOL) questionnaire (EQ-5D) scores, Rutherford classification, mortality, patency rate and details of major adverse cardiovascular events were collected at 6-, 12-, 18-, and 24-month follow ups. Results: PTA with/without stenting achieved 90.3 %, 86.5 %, 82.7 %, and 71.9 % technical success (recanalisation achieving ≥ 70 % patency, no evidence of embolisation, recoiling or dissection) in iliac, femoral, popliteal, and below-the-knee arteries, respectively. Procedural/postprocedural complications occurred in 142 (9.3 %, 1 death) and 74 (4.8 %) patients. QOL, mobility, self-care, activity, and pain/discomfort scores improved (p < 0.01), anxiety/depression was insignificantly improved. During follow-up, 409 (26.7 %) patients were hospitalised for PAD, 281 (18.3 %) required reintervention, and 145 (9.5 %) died or needed amputation (n = 49; 3.2 %). Multivariate analysis demonstrated poorer outcomes in patients with comorbidities. Conclusions: PTA with/without stenting is effective, safe, and widely applicable, with few complications. It improves QOL, but not anxiety/depression.
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- 2019
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13. German multicenter real-world registry of stenting for superficial femoral artery disease: clinical results and predictive factors for revascularization.
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Krankenberg H, Tübler T, Sixt S, Fischer M, Schmiedel R, Schulte KL, Balzer JO, Kieback A, Fiehn E, Wittenberg G, Ali T, Tiefenbacher C, Jahnke T, Steinkamp HJ, Wegscheider K, Treszl A, Ingwersen M, and Zeller T
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- Aged, Alloys, Angioplasty, Balloon adverse effects, Constriction, Pathologic, Female, Germany, Humans, Intermittent Claudication diagnosis, Ischemia diagnosis, Kaplan-Meier Estimate, Logistic Models, Male, Middle Aged, Multivariate Analysis, Odds Ratio, Peripheral Arterial Disease diagnosis, Prospective Studies, Prosthesis Design, Recurrence, Registries, Risk Factors, Sex Factors, Time Factors, Treatment Outcome, Angioplasty, Balloon instrumentation, Femoral Artery, Intermittent Claudication therapy, Ischemia therapy, Peripheral Arterial Disease therapy, Stents
- Abstract
Purpose: To investigate nitinol stent treatment of superficial femoral artery (SFA) lesions and the impact of different risk factors on the need for clinically driven target lesion revascularization (TLR) in a large, real-world population of claudicants., Methods: Patients presenting with symptomatic SFA stenosis >70% were consecutively enrolled in the 13-center MARIS prospective registry (ClinicalTrials.gov identifier NCT01067885). There was no restriction on lesion length, thus leading to the inclusion of a real-world as well as high-risk patient cohort. The 998 participating patients (657 men; mean age 67.4±9.2 years) had 1050 lesions treated with the same nitinol stent type. The mean lesion length was 9.5±9.6 cm (range 0.5-44; median 8.0); more than a third of the lesions (450, 42.9%) were total occlusions. The primary endpoint was the need for clinically driven target lesion revascularization (TLR) at 12 months., Results: Acute technical success was achieved in 1042 (99.2%) lesions. Restenosis occurred in 187 (23.7%) and reocclusion in 79 (10.0%) lesions at 12 months. The primary endpoint of TLR at 12 months was reached by 136 (17.2%) patients. The periprocedural complication rate was 5.4%. Independent predictors of TLR were female gender [odds ratio (OR) 0.5, 95% confidence interval (CI) 0.3 to 0.7, p<0.001] and lesion length >20 cm vs. 10 cm (OR 2.7, 95% CI 1.1 to 6.6, p=0.029) and 10-20 cm vs. 10 cm (OR 1.9, 95% CI 1.0 to 4.1, p=0.047)., Conclusion: Stent implantation in the SFA is safe and associated with favorable acute and midterm results in a real-world setting. Lesion length and female gender were identified as independent risk factors for TLR.
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- 2014
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14. PEACE I all-comers registry: patency evaluation after implantation of the 4-French Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions.
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Lichtenberg M, Kolks O, Hailer B, Stahlhoff WF, Tiefenbacher C, Nolte-Ernsting C, Arjumand J, and Wittenberg G
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- Aged, Aged, 80 and over, Angioplasty adverse effects, Constriction, Pathologic, Disease-Free Survival, Female, Femoral Artery diagnostic imaging, Germany, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Peripheral Arterial Disease diagnosis, Peripheral Arterial Disease physiopathology, Popliteal Artery diagnostic imaging, Prospective Studies, Prosthesis Design, Recurrence, Registries, Time Factors, Treatment Outcome, Ultrasonography, Doppler, Duplex, Alloys, Angioplasty instrumentation, Femoral Artery physiopathology, Peripheral Arterial Disease therapy, Popliteal Artery physiopathology, Stents, Vascular Patency
- Abstract
Purpose: To evaluate the 1-year patency of the 4-F Pulsar-18 self-expanding nitinol stent for treatment of femoropopliteal occlusive disease in a national, prospective, multicenter, all-comers registry., Methods: Between January and June 2012, the German PEACE I all-comers prospective registry enrolled 148 patients with symptomatic femoropopliteal lesions (Rutherford category 2-5) undergoing recanalization and implantation of the Pulsar-18 SE nitinol stent at 6 clinical centers. Thirty patients did not have the 12-month follow-up visit (18 declined reevaluation, 5 withdrew consent, and 7 died), leaving 118 patients (64 men; mean 71.9±9.6 age years) for the 1-year evaluation. The average lesion length was 111.5±71.4 mm, and 38 of the 118 lesions were classified as TASC II D. More than half the lesions (67, 56.7%) were chronic total occlusions (CTO). The popliteal segment was involved in 22 (18.7%) lesions. The mean stented length was 122.7±64.5 mm. Routine follow-up included duplex ultrasound at 6 and 12 months. Outcome measures were primary patency and no clinically driven target lesion revascularization (TLR) within 12 months., Results: The overall primary patency rates after 6 and 12 months were 87.4% and 79.5%, respectively; in the popliteal segments, the rate was 71.4% after 12 months. The overall freedom from TLR was 93.2% after 6 months and 81% after 12 months. Ankle-brachial index, pain-free walking distance, and Rutherford category all improved significantly (p<0.0001) after 6 and 12 months. The primary patency rates in patients with diabetes (p=1.0) and those with renal insufficiency (p=0.8) were not significantly lower compared to the overall rate. There was no significant difference (p=0.67) in restenosis rate for recanalization of CTOs compared to non-CTO lesions., Conclusions: In this all-comers registry, the use of the Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions averaging 111.5 mm long showed promising primary patency and freedom from TLR after 6 and 12 months. Diabetes had no negative impact on patency. Primary patency in the popliteal segments was acceptable at 12 months.
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- 2014
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15. [Curriculum for interventional therapy for arterial diseases. Clinical competence for execution of catheter-based interventions on the arteries of the extremities, on the pelvic, visceral and renal arteries, on the extracranial arteries supplying the brain, and on dialysis shunts].
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Schulte KL, Amendt K, Hoffmann U, Tiefenbacher C, Weiss T, Mudra H, Hardung D, and Nikol S
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- Consensus, Germany, Humans, Catheterization, Peripheral, Certification standards, Clinical Competence standards, Competency-Based Education standards, Education, Medical, Graduate standards, Endovascular Procedures education, Endovascular Procedures standards, Peripheral Arterial Disease therapy
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- 2012
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16. Effect of insulin and glucose infusion on myocardial infarction size in uraemic rats.
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Dikow R, Wasserhess C, Zimmerer K, Kihm LP, Schaier M, Schwenger V, Hardt S, Tiefenbacher C, Katus H, Zeier M, and Gross LM
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- Animals, Blotting, Western, Disease Models, Animal, Glucose Transporter Type 4 metabolism, Infusions, Parenteral, Insulin Receptor Substrate Proteins metabolism, Male, Myocardial Infarction complications, Myocardial Infarction pathology, Myocardial Infarction physiopathology, Myocardial Reperfusion Injury complications, Myocardial Reperfusion Injury pathology, Myocardial Reperfusion Injury physiopathology, Myocardium metabolism, Nephrectomy, Rats, Rats, Sprague-Dawley, Time Factors, Uremia complications, Uremia pathology, Uremia physiopathology, Glucose administration & dosage, Insulin administration & dosage, Insulin Resistance, Myocardial Infarction drug therapy, Myocardial Reperfusion Injury drug therapy, Myocardium pathology, Uremia drug therapy
- Abstract
The post myocardial infarction (MI) mortality rate is high in renal patients. One possible explanation is the reduced ischemia tolerance caused by uraemia. Previous investigations showed larger MI size in uraemic rats when compared with sham-operated controls. To explore a possible link between uraemic insulin resistance syndrome and MI size in uraemia, we studied an intervention model with administration of insulin and glucose during acute MI in subtotally nephrectomized (SNX) rats and sham-operated controls. In 16 SNX rats and 16 sham-operated controls, the left coronary artery was ligated for 60 min, followed by reperfusion for 90 min. To visualize the perfused myocardium, lissamine-green ink was injected. The nonperfused area (lissamine exclusion) and the area of total infarction (TTC stain) were assessed in sections of the left ventricle (LV) using image analysis. While eight SNX rats and eight sham-operated controls were treated with a placebo during the procedure, the other animals received an insulin bolus of 85 mU/kg and then a continuous insulin infusion of 8 mU/kg per minute. Blood glucose levels were clamped to baseline levels with an infusion of 25% glucose. Insulin receptor substrates (IRS-1 and IRS-2) and glucose transporter (GLUT 4) were studied by western blot in another seven SNX and seven sham-operated controls without further intervention. The infarcted area, given as a proportion of the nonperfused risk area, was not different in sham-operated controls treated with a hyperinsulinaemic clamp versus untreated (0.55 +/- 0.07 vs. 0.51 +/- 0.13, p = 0.477). The eight SNX animals treated with the hyperinsulinaemic clamp utilized significantly less glucose to stabilize baseline glucose levels when compared with the sham-operated controls (5,637 vs. 3,207 microl Glc 25%, p = 0.007). The infarcted area was significantly lower in SNX rats treated with the hyperinsulinaemic clamp compared to non-treated SNX animals (0.56 +/- 0.06 vs. 0.79 +/- 0.09, p < 0.001). SNX rats with the insulin clamp had the same infarcted area size as sham-operated controls (0.56 +/- 0.06 vs. 0.51 +/- 0.13, p = 0.357). Western blotting did not show any change in the expression of GLUT 4 and IRS-1/IRS-2 in SNX animals when compared with sham-operated controls. The size of MI in uraemic rats is significantly reduced by a glucose/insulin infusion. The results suggest an insulin resistance in uraemic rats with similar benefits of glucose/insulin application during acute MI, as found in diabetic individuals. Further analysis did not reveal a down regulation in GLUT 4 and IRS-1/IRS-2.
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- 2009
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17. Transcatheter closure of patent foramen ovale with radiofrequency: acute and intermediate term results in 144 patients.
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Sievert H, Ruygrok P, Salkeld M, Baumgartner H, Meier B, Windecker S, Juliard JM, Aubry P, Tiefenbacher C, Krumsdorf U, Vermeersch P, Ewert P, and Piéchaud JF
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- Adult, Aged, Cardiac Catheterization instrumentation, Catheter Ablation instrumentation, Equipment Design, Equipment Safety, Feasibility Studies, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prospective Studies, Treatment Outcome, Cardiac Catheterization methods, Catheter Ablation methods, Foramen Ovale, Patent surgery
- Abstract
Aims: Currently available devices for transcatheter closure of patent foramen ovale (PFO) which rely on a permanent implant have limitations, including late complications. The study objective was to evaluate the safety, feasibility, and effectiveness of the PFx Closure System, the first transcatheter technique for PFO closure without an implantable device., Methods and Results: A prospective study of 144 patients was conducted at nine clinical sites from October 2005 through August 2007. All patients had a history of cryptogenic stroke, transient ischemic attack, migraines, or decompression illness. The mean balloon stretched diameter of the PFO was 7.9 +/- 2.5 mm. Technical success (successful application of radiofrequency energy) was achieved in 130 patients. One patient required a transfusion as a result of blood loss during the procedure. There were no other major procedural complications. There were no recurrent strokes, deaths, conduction abnormalities, or perforations following the procedure. At a mean follow-up of 6 months, successful closure was achieved in 79 patients (55%). In PFOs with balloon sized or stretched diameters less than 8 mm, the closure rate was 72% (53/74)., Conclusion: This study demonstrates that transcatheter closure of a PFO without a permanent implant is technically feasible and safe. Further technique and device modifications are required to achieve higher closure rates., (Copyright 2009 Wiley-Liss, Inc.)
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- 2009
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18. Nitinol stent implantation in TASC A and B superficial femoral artery lesions: the Femoral Artery Conformexx Trial (FACT).
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Zeller T, Tiefenbacher C, Steinkamp HJ, Langhoff R, Wittenberg G, Schlüter M, Buergelin K, Rastan A, Krumsdorf U, Sixt S, Schulte CL, Tübler T, and Krankenberg H
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- Aged, Alloys, Blood Vessel Prosthesis Implantation methods, Female, Femoral Artery diagnostic imaging, Femoral Artery pathology, Humans, Male, Peripheral Vascular Diseases diagnostic imaging, Peripheral Vascular Diseases pathology, Treatment Outcome, Ultrasonography, Vascular Patency, Femoral Artery surgery, Peripheral Vascular Diseases surgery, Stents
- Abstract
Purpose: To investigate the impact of nitinol stenting of superficial femoral artery (SFA) lesions with a maximum length of 10 cm (TASC-II A or B) on 1-year outcomes compared to a historical study cohort from the Femoral Artery Stent Trial (FAST)., Methods: Between January 2004 and August 2005, 6 study sites enrolled 110 symptomatic patients (75 men; mean age 68+/-9 years) with a single de novo >70% SFA lesion <10 cm long treated with the self-expanding nitinol Conformexx stent. The primary study endpoint was binary restenosis determined by duplex ultrasound at 12 months. Secondary 12-month endpoints were target lesion revascularization (TLR), ankle-brachial index (ABI), mean Rutherford category, >1-class change in Rutherford category, and major adverse events. Data were analyzed according to the intention-to-treat principle and according to the actual treatment received ("on treatment" analysis). Outcomes were compared to the historical balloon angioplasty (BA) arm and the Luminexx 3 stent arm of the randomized FAST study., Results: Technical success was achieved in 106 (96%) patients; at 1 year, the primary endpoint of ultrasound-assessed binary restenosis was reached in 14 (23.3%) of 60 patients (95% CI 13.4% to 36%). This restenosis rate was lower versus the historical BA (38.6%, p=0.057) or Luminexx 3 stent controls (31.7%, p=0.284) from FAST. The clinically driven TLR was 7.4% (7 of 94 clinically controlled patients), which was also lower compared to 18.3% (p=0.098) and 14.9% (p=0.267) for the historical BA and Luminexx 3 stent groups, respectively. The mean Rutherford category was reduced from 2.75+/-0.79 to 0.94+/-1.38 (p<0.0001); 85.1% were improved by at least 1 Rutherford category. The ABI increased from 0.62+/-0.15 to 0.85+/-0.20 (p<0.0001)., Conclusion: This study of patients with SFA lesions documented favorable outcomes using nitinol stents in TASC-II A or B lesions after 1 year. The study was underpowered to prove superiority of the Conformexx nitinol stent design compared to historical balloon only or Luminexx 3 stent groups.
- Published
- 2008
- Full Text
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19. Treatment of iatrogenic femoral pseudoaneurysm by ultrasound-guided compression therapy and thrombin injection.
- Author
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Luedde M, Krumsdorf U, Zehelein J, Ivandic B, Dengler T, Katus HA, and Tiefenbacher C
- Subjects
- Femoral Artery diagnostic imaging, Follow-Up Studies, Humans, Iatrogenic Disease, Injections, Intra-Arterial, Pressure, Retrospective Studies, Treatment Outcome, Aneurysm, False diagnostic imaging, Aneurysm, False etiology, Aneurysm, False therapy, Cardiac Catheterization adverse effects, Femoral Artery injuries, Hemostatic Techniques, Hemostatics administration & dosage, Thrombin administration & dosage, Ultrasonography, Doppler, Duplex
- Abstract
Development of an arterial pseudoaneurysm is a common complication following cardiac catheterization. We analyzed data from 6,300 patients who received left heart catheterization at our institution. One day after the procedure, approximately 10% of the patients were examined with duplex sonography. In 204 patients (3.0%), a pseudoaneurysm of the femoral artery was diagnosed. All patients underwent compression therapy. Thereby, 159 of the pseudoaneurysms could be treated successfully. The remaining 45 pseudoaneurysms had a maximal diameter of more than 1.5 cm. Forty-two patients underwent ultrasound and biopsy-line-guided thrombin injection without complications. This strategy resulted in a successful occlusion in 41 cases. Pseudoaneurysms smaller than 2 cm can be treated with compression therapy. Larger pseudoaneurysms can be occluded by thrombin injection using ultrasound guidance. Patients with a pseudoaneurysm with a wide "neck" should be treated surgically, because the risk of an arterial occlusion following thrombin injection cannot be excluded.
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- 2007
- Full Text
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20. Patent foramen ovale using the Premere device: the results of the CLOSEUP trial.
- Author
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Büscheck F, Sievert H, Kleber F, Tiefenbacher C, Krumsdorf U, Windecker S, Uhlemann F, and Wahr DW
- Subjects
- Adolescent, Adult, Aged, Echocardiography, Equipment Safety, Female, Follow-Up Studies, Heart Septal Defects, Atrial diagnostic imaging, Humans, Male, Middle Aged, Postoperative Complications etiology, Prospective Studies, Prosthesis Design, Treatment Outcome, Cardiac Surgical Procedures instrumentation, Heart Septal Defects, Atrial surgery
- Abstract
Objectives: The CLOSEUP trial was conducted to determine the safety and effectiveness of the Premere closure device in closure of patent foramen ovale (PFO)., Background: PFO is a relatively common congenital condition, associated with cryptogenic stroke and migraine with aura. The Premere device is specifically designed to close PFO of variable size and length, with right and left anchor arms connected by a flexible tether. The device has an open architecture, a low profile, and a small surface area on the left atrial side which may discourage thrombus formation., Methods: Patients between 18 and 65 years of age who had a cryptogenic ischemic stroke or a transient ischemic attack and a PFO underwent percutaneous PFO closure using the Premere device., Results: Of the 73 enrolled patients, six patients had atrial anatomy not appropriate for the Premere; 27 patients received the 15 mm and 40 patients received the 20 mm device. Implantation was successful in all patients. At 6 months of follow-up, 86% of patients had no shunt that could be provoked with Valsalva as assessed during contrast echocardiography. Closure rates were better with the 20 mm versus the 15 mm device, and three patients with residual shunt had atrial septal aneurysms at baseline. One patient had transient atrial fibrillation which resolved by 3 months. There were no instances of thrombus, death, or stroke., Conclusions: These data demonstrate that the Premere device can safely and effectively close PFO. Additional studies should be undertaken to demonstrate the effectiveness of PFO closure in reducing thrombo-embolic events such as stroke.
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- 2006
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21. Upregulation of ID protein by growth and differentiation factor 5 (GDF5) through a smad-dependent and MAPK-independent pathway in HUVSMC.
- Author
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Chen X, Zankl A, Niroomand F, Liu Z, Katus HA, Jahn L, and Tiefenbacher C
- Subjects
- Bone Morphogenetic Proteins pharmacology, Cell Movement drug effects, Cell Proliferation drug effects, Cells, Cultured, Enzyme Inhibitors pharmacology, Growth Differentiation Factor 5, Humans, Inhibitor of Differentiation Protein 1 drug effects, Inhibitor of Differentiation Protein 1 genetics, Inhibitor of Differentiation Protein 1 metabolism, Inhibitor of Differentiation Proteins drug effects, Inhibitor of Differentiation Proteins genetics, Mitogen-Activated Protein Kinases antagonists & inhibitors, Mitogen-Activated Protein Kinases metabolism, Muscle, Smooth, Vascular metabolism, Neovascularization, Physiologic, Phosphorylation, Protein Transport, RNA, Small Interfering, Smad1 Protein drug effects, Smad1 Protein genetics, Smad1 Protein metabolism, Transcription, Genetic, Up-Regulation, Bone Morphogenetic Proteins metabolism, Inhibitor of Differentiation Proteins metabolism, Muscle, Smooth, Vascular cytology, Signal Transduction, Smad Proteins metabolism
- Abstract
GDF5 (growth and differentiation factor five), a member of the TGF-beta superfamily, binds specifically to BMPR1b, BMPR2 and ACTR2a receptors forming a heterodimeric complex, thereby inducing phosphorylation of smad1, 5, 8 and translocation to the nucleus. ID1 (inhibitor of differentiation or DNA binding) is essential for G1 to S phase transition inhibiting DNA binding thereby playing an important role in the control of differentiation, proliferation and angiogenesis. The objective of this study was, therefore, to characterize the signal transduction pathway of GDF5, especially the involvement of ID1, in human umbilical vein smooth muscle cells (HUVSMC). We observed the expression of BMPR1a, BMPR1b, BMPR2, ACTR2a, smad1, smad 5, ID1, ID2 and ID3 in HUVSMC. Application of GDF5 upregulated ID1 and ID3 expression by involvement of the smad signaling pathway. GDF5 caused phorsphorylation of smad1 followed by upregulation of ID1 and ID3. Co-incubation with anti-GDF5 prevented these effects. GDF5 significantly inhibited phosphorylation of p38 MAPK and induced phosphorylation of ERK. The specific inhibitor of p38 MAPK or ERK, SB203580 or U0126 did not induce ID protein expression. Smad1 siRNA transfection inhibited the upregulation of ID protein. GDF5 had chemotactic activity in HUVSMC; this effect was partly blocked by transfection of smad1 or ID1 siRNA. Our results indicate that GDF5 induces ID1 and ID3 in HUVSMC by a smad-dependent, MAPK-independent pathway. GDF5 binds to specific receptors, thereby inducing phosphorylation and translocation of smad1 to the nucleus where it is involved in the regulation of transcription. Since ID1 has been shown to be crucial for cell cycle control, we propose that GDF5 could be involved in the process of angiogenesis.
- Published
- 2006
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22. Increased infarct size in uremic rats: reduced ischemia tolerance?
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Dikow R, Kihm LP, Zeier M, Kapitza J, Törnig J, Amann K, Tiefenbacher C, and Ritz E
- Subjects
- Animals, Body Weight, Coronary Vessels pathology, Heart Ventricles pathology, Hydralazine pharmacology, Imidazoles pharmacology, Ischemia, Male, Myocardium pathology, Nadolol pharmacology, Necrosis, Nephrectomy, Perfusion, Rats, Rats, Sprague-Dawley, Reperfusion, Salts pharmacology, Time Factors, Myocardial Infarction pathology, Myocardial Ischemia, Uremia pathology
- Abstract
In patients with renal failure, myocardial infarction (MI) is more frequent and the rate of death from acute MI is very high. It has been argued that ischemia tolerance of the heart is reduced in uremia, but direct evidence for this hypothesis has not been provided. It was the purpose of this study (1) to ligate the left coronary artery and to measure the nonperfused area (risk area: total infarction plus penumbra) as well as the area of total infarction in subtotally nephrectomized (SNX) rats compared with sham-operated pair-fed control rats and (2) to examine the effects of potential confounders such as BP, sympathetic overactivity, and salt retention. The left coronary artery was ligated for 60 min, followed by reperfusion for 90 min. For visualizing perfused myocardium, lissamine green ink was injected. The nonperfused area (lissamine exclusion) and the area of total infarction (triphenyltetrazolium chloride stain) were assessed in sections of the left ventricle using image analysis. Groups of SNX rats also received: antihypertensive treatment (nadolol plus hydralazine); moxonidine; high salt diet or low salt diet (1.58% versus 0.015%). In surviving animals, the nonperfused area at risk (as the proportion of total left ventricular area), presumably determined by the geometry of vascular supply, was similar in sham-operated and SNX animals (0.38 +/- 0.13 versus 0.45 +/- 0.09; NS). In contrast, the infarcted area, given as a proportion of the nonperfused risk area, was significantly (P < 0.003) higher in SNX (0.68 +/- 0.09) compared with sham-operated (0.51 +/- 0.11) rats and was not altered by any of the above interventions. The finding that a greater proportion of nonperfused myocardium undergoes total necrosis is consistent with the hypothesis of reduced ischemia tolerance of the heart in renal failure. The findings could explain the high rate of death from MI in patients with impaired renal function.
- Published
- 2004
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23. Plasma membrane-associated nucleoside diphosphate kinase (nm23) in the heart is regulated by beta-adrenergic signaling.
- Author
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Lutz S, Mura RA, Hippe HJ, Tiefenbacher C, and Niroomand F
- Subjects
- Adenylyl Cyclases metabolism, Adrenergic beta-Agonists pharmacology, Adrenergic beta-Antagonists therapeutic use, Adult, Aged, Animals, Cardiomegaly chemically induced, Cardiomegaly metabolism, Cardiomyopathy, Dilated drug therapy, Heart Defects, Congenital drug therapy, Humans, Isoproterenol pharmacology, Male, Middle Aged, Models, Biological, Myocardium pathology, Rats, Rats, Wistar, Receptors, Adrenergic, beta drug effects, Receptors, Adrenergic, beta metabolism, Sarcolemma enzymology, Thyroid Hormones pharmacology, Time Factors, Adrenergic beta-Antagonists pharmacology, Myocardium enzymology, Nucleoside-Diphosphate Kinase metabolism, Sarcolemma drug effects
- Abstract
1. Receptor-independent activation of heterotrimeric G proteins by plasma membrane-associated nucleoside diphosphate kinase (NDPK) has been demonstrated in vivo, and elevated levels of NDPK were found in purified sarcolemmal membranes of patients with end-stage heart failure. 2. Among 22 consecutive patients with chronic heart failure who underwent cardiac transplantation, those treated with a beta-blocker (n=8) had a 65% lower NDPK content and activity in the cardiac sarcolemma, compared to patients with similar base line characteristics who had no beta-blocker therapy (n=14). 3. The lower NDPK was associated with a reduced NDPK-dependent, Gi-mediated inhibition of adenylyl cyclase activity, as assessed by in vitro measurement of adenylyl cyclase activity in the presence of GDP or its kinase-resistant analog guanosine 5'-O-(2-thio)diphosphate (GDPbetaS). 4. We further tested whether treatment with a beta-adrenergic agonist would induce an increase in sarcolemmal NDPK. Rats treated with isoproterenol developed myocardial hypertrophy, and NDPK in the sarcolemma rose by 60% during 14 days of treatment. The beta-blocker propranolol prevented both effects. When hypertrophy was induced with thyroid hormone, NDPK did not increase. 5. In conclusion, chronic activation of beta-adrenergic receptors increases the binding of NDPK to cardiac sarcolemma, where it may activate heterotrimeric G proteins.
- Published
- 2003
- Full Text
- View/download PDF
24. Comparative follow up of patients with implanted cardioverter-defibrillators after induction of sustained monomorphic ventricular tachycardias or ventricular fibrillation by programmed stimulation.
- Author
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Meyborg M, Mura R, Tiefenbacher C, Becker R, Michaelsen J, and Niroomand F
- Subjects
- Aged, Clinical Protocols, Cohort Studies, Electric Stimulation Therapy methods, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prospective Studies, Risk Factors, Survival Analysis, Death, Sudden, Cardiac prevention & control, Defibrillators, Implantable, Tachycardia, Ventricular therapy, Ventricular Fibrillation therapy
- Abstract
Objective: To investigate the prognostic value of induced monomorphic ventricular tachycardia (VT) and ventricular flutter or fibrillation (VF) during programmed electrical stimulation in patients with a high risk for sudden arrhythmogenic cardiac death., Design: Prospective cohort study., Patients: 102 patients at high risk for arrhythmogenic sudden cardiac death who received an automated implantable cardioverter-defibrillator (AICD) were evaluated. 56 patients received the AICD for primary prevention and 46 for secondary prevention. 58 patients had induction of a monomorphic VT (VT group) and 44 had induction of a polymorphic VT, ventricular flutter, or ventricular fibrillation (VF group) during programmed electrical stimulation. Average follow up was 20 months in both groups., Main Outcome Measures: Appropriate AICD protocol., Results: In patients who received the AICD for primary prevention, 16 of 32 patients in the VT group, compared with only four of 24 patients in the VF group, received an appropriate AICD protocol (p = 0.02). In the entire study population, 479 appropriate AICD protocols were recorded in 28 (48%) patients in the VT group and 28 appropriate protocols in 11 (25%) patients in the VF group. Cumulative Kaplan-Meier event-free survival curves were significantly different (p = 0.02)., Conclusion: Induction of VF during programmed electrical stimulation is of no prognostic value even in high risk patients without previously documented ventricular fibrillation.
- Published
- 2003
- Full Text
- View/download PDF
25. Activation of neutrophils in the microvasculature of the ischaemic and reperfused myocardium.
- Author
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Tillmanns H, Neumann FJ, Tiefenbacher C, Dorigo O, Parekh N, Waas W, Zimmermann R, Steinhausen M, and Kuebler W
- Subjects
- Angioplasty, Balloon, Coronary, Animals, Blood Flow Velocity, Capillary Permeability, Cell Adhesion, Coronary Circulation drug effects, Coronary Circulation immunology, Coronary Vessels immunology, Coronary Vessels physiopathology, Humans, Leukocytes physiology, Microcirculation drug effects, Microcirculation immunology, Microcirculation physiopathology, Myocardial Stunning immunology, Nifedipine pharmacology, Rats, Coronary Circulation physiology, Myocardial Stunning physiopathology, Neutrophils physiology
- Abstract
In 11 rats, the microcirculation of the repeatedly ischaemic (stunned) left ventricular myocardium was studied using in vivo fluorescence microscopy. Stunning was provoked by six subsequent 10 min ligations of the left anterior descending coronary artery, each of them followed by a 20 min reperfusion period. In the stunned myocardium showing hypokinetic wall motion, myocardial blood flow dropped by 55%; in this region, leukocytes often appeared in slow-flow capillaries plugging capillary branches. Closely linking to leukocyte adherence, a rise of microvascular permeability was documented by extravascular clouds of fluorescent dextran. After nifedipine treatment, in ischaemic regions marked dilatation of larger A1 and A2 arterioles was noted, in addition to the ischaemia-induced dilatation of smaller A3 and A4 arterioles. Furthermore nifedipine and nisoldipine reduced the number of adherent leukocytes in post-capillary venules and capillaries of the repeatedly ischaemic myocardium. In 12 patients with coronary one-vessel disease and without previous transmural myocardial infarction, elective coronary angioplasty (PTCA) was performed (balloon inflation for 2 min). After elective PTCA of the LAD, a significant rise in the proportion of activated neutrophils was noted. After elective 2 min PTCA of the LAD, coronary sinus blood samples showed a marked rise of FMLC stimulated superoxide anion production, whereas passive deformability decreased considerably. Furthermore, an increase in chemotactic activity in coronary sinus blood samples was observed.
- Published
- 1993
26. Pharmacologic effects on coronary microvessels during myocardial ischaemia.
- Author
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Tillmanns H, Neumann FJ, Parekh N, Dorigo O, Tiefenbacher C, Zimmermann R, Steinhausen M, and Kübler W
- Subjects
- Animals, Blood Flow Velocity, Capillary Permeability, Coronary Circulation drug effects, Coronary Disease drug therapy, Erythrocyte Count, Fatty Acids metabolism, Microcirculation drug effects, Platelet Count drug effects, Rats, Thromboxane-A Synthase antagonists & inhibitors, Coronary Disease physiopathology, Coronary Vessels drug effects, Gallopamil pharmacology, Imidazoles pharmacology, Indomethacin pharmacology, Verapamil pharmacology
- Published
- 1990
- Full Text
- View/download PDF
27. Microcirculation in the hypertrophic and ischemic heart.
- Author
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Tillmanns H, Neumann FJ, Parekh N, Zimmermann R, Tiefenbacher C, Dorigo O, Steinhausen M, and Kübler W
- Subjects
- Animals, Blood Flow Velocity, Capillaries pathology, Cardiomegaly etiology, Coronary Disease etiology, Hypertension complications, Microcirculation pathology, Microscopy, Fluorescence, Myocardial Reperfusion, Rats, Cardiomegaly pathology, Coronary Vessels pathology
- Abstract
1. Myocardial hypertrophy, for instance in patients with hypertensive heart disease, is characterized by a reduction of coronary vascular reserve, even in the presence of normal coronary arteries. In hypertensive animals, on the microcirculatory level functional changes can be observed before the onset of any structural rarefications. In 10 rats with renal hypertension and pressure-induced left ventricular hypertrophy (LVH), the microcirculation of the left ventricular myocardium was studied using in vivo fluorescence microscopy and morphometric analysis. Renal hypertension was provoked by clipping of the left renal artery. After 8 weeks, systolic blood pressure in LVH rats averaged 172 +/- 8 mm Hg, compared to 91 +/- 2 mm Hg in 10 normotensive (NT) rats. In LVH rats, distances of plasma-perfused capillaries were significantly increased (NT = 17.7; LVH = 20 microns; p less than 0.001). Volume density, surface density, and length density of capillaries in LVH rats were reduced by 20% compared to NT rats. Capillary red cell content as measured by the ratio of capillaries filled with red cells to those containing plasma alone (Q) in LVH animals exceeded that in NT rats (LVH: Q = 0.83 +/- 0.04; NT: Q = 0.77 +/- 0.04; p less than 0.025). During hypoxia (H, 5% O2) capillary red cell recruitment in LVH rats (Q: control c = 0.83; H = 0.95) was diminished by 33% as compared to NT rats (Q: c = 0.77; H = 0.95). Thus, in addition to the decreased capillary density, the reduction of capillary red cell recruitment may be responsible for chest pain in patients with LVH and normal coronary arteries.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1990
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