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Tirone E David - One of the best experts on this subject based on the ideXlab platform.
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chordal replacement with polytetrafluoroethylene sutures for mitral valve repair a 25 year experience
The Journal of Thoracic and Cardiovascular Surgery, 2013Co-Authors: Tirone E David, Susan Armstrong, Joan IvanovAbstract:Objective The study objective was to examine the late results of mitral valve repair with chordal replacement with polytetrafluoroethylene sutures. Methods From 1986 to 2004, 606 consecutive patients with degenerative mitral regurgitation had mitral valve repair with chordal replacement with polytetrafluoroethylene sutures. Patients' mean age was 57 years, and 73.6% were men. Isolated prolapse of the anterior leaflet was present in 17.6% of patients, isolated posterior leaflet prolapse was present in 29.5% of patients, and bileaflet prolapse was present in 52.9% of patients. Prolapse was corrected by creating 2 to 38 neochords of polytetrafluoroethylene sutures (mean, 13 ± 9 per patient). The mean follow-up was 10.1 years, and 96% of the patients had multiple echocardiographic studies over the years. Results There were 5 early and 106 late deaths. Age, diabetes, hypertension, chronic obstructive lung disease, New York Heart Association functional classes III and IV, and ejection fraction less than 40% were independent predictors of mortality. At 18 years, freedom from reoperation on the mitral valve was 90.2% ± 2.4%, freedom from recurrent severe mitral regurgitation was 91.0% ± 2.7%, and freedom from moderate or severe mitral regurgitation was 67.5% ± 4.2%. Cox regression analysis revealed that isolated prolapse of the anterior leaflet was predictive of reoperation, and that older age, hypertension, and left ventricular ejection fraction less than 40% were predictive of recurrent moderate or severe mitral regurgitation. Conclusions Chordal replacement with polytetrafluoroethylene sutures expands the indication of repair to patients with prolapse of multiple segments. Valve function remains stable in most patients during the first 2 decades of follow-up.
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ruptured synthetic expanded polytetrafluoroethylene chordae tendinae
Cardiovascular Pathology, 2004Co-Authors: Tirone E David, Jagdish Butany, Michael J CollinsAbstract:Synthetic sutures are used for mitral valve repair and as synthetic chordae tendinae to resuspend the mitral valve. The sutures soon get covered with connective tissue and work well for long periods. We report the first instance (in the literature) of rupture of a synthetic (PTFE) chordae tendinae. The synthetic suture (PTFE) was associated with calcification.
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long term results of mitral valve repair for myxomatous disease with and without chordal replacement with expanded polytetrafluoroethylene sutures
The Journal of Thoracic and Cardiovascular Surgery, 1998Co-Authors: Tirone E David, Ahmad S Omran, Susan Armstrong, Joan IvanovAbstract:Abstract Objective: This study was carried out to evaluate the long-term results of mitral valve repair for mitral regurgitation caused by myxomatous disease of the mitral valve and the late effects of chordal replacement with expanded polytetrafluoroethylene sutures in this operation. Methods: A total of 324 patients with mitral regurgitation caused by myxomatous disease underwent mitral valve repair from 1981 to 1995; the group comprised 241 men and 83 women whose mean age was 58 ± 14 years. Chordal replacement with expanded polytetrafluoroethylene sutures has been performed in 165 patients since 1985. Most of the patients who had chordal replacement with expanded polytetrafluoroethylene sutures had prolapse of the anterior leaflet or prolapse of both leaflets, whereas most patients who had mitral valve repair without chordal replacement had prolapse of the posterior leaflet. Patients were followed up at annual intervals and had a Doppler echocardiographic study. The follow-up was complete and extended from 6 to 156 months (mean 36 ± 30 months). Results: Two operative and 21 late deaths occurred (14 cardiac and 7 noncardiac). At 10 years the actuarial survival was 75% ± 5%, the freedom from stroke was 94% ± 2%, the freedom from transient ischemic attacks was 92% ± 4%, the freedom from endocarditis was 99% ± 1%, the freedom from mitral valve reoperation was 96% ± 1%, and the freedom from severe mitral regurgitation was 93% ± 3%. Chordal replacement with expanded polytetrafluoroethylene sutures had no effect on any of these end points. Conclusions: Mitral valve repair was feasible in most patients with mitral regurgitation caused by myxomatous disease and it was associated with low rates of valve-related complications. Chordal replacement with expanded polytetrafluoroethylene had no adverse effect on the late outcome and was believed to have increased the probability of mitral valve repair. (J Thorac Cardiovasc Surg 1998;115:1279-86)
Joan Ivanov - One of the best experts on this subject based on the ideXlab platform.
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chordal replacement with polytetrafluoroethylene sutures for mitral valve repair a 25 year experience
The Journal of Thoracic and Cardiovascular Surgery, 2013Co-Authors: Tirone E David, Susan Armstrong, Joan IvanovAbstract:Objective The study objective was to examine the late results of mitral valve repair with chordal replacement with polytetrafluoroethylene sutures. Methods From 1986 to 2004, 606 consecutive patients with degenerative mitral regurgitation had mitral valve repair with chordal replacement with polytetrafluoroethylene sutures. Patients' mean age was 57 years, and 73.6% were men. Isolated prolapse of the anterior leaflet was present in 17.6% of patients, isolated posterior leaflet prolapse was present in 29.5% of patients, and bileaflet prolapse was present in 52.9% of patients. Prolapse was corrected by creating 2 to 38 neochords of polytetrafluoroethylene sutures (mean, 13 ± 9 per patient). The mean follow-up was 10.1 years, and 96% of the patients had multiple echocardiographic studies over the years. Results There were 5 early and 106 late deaths. Age, diabetes, hypertension, chronic obstructive lung disease, New York Heart Association functional classes III and IV, and ejection fraction less than 40% were independent predictors of mortality. At 18 years, freedom from reoperation on the mitral valve was 90.2% ± 2.4%, freedom from recurrent severe mitral regurgitation was 91.0% ± 2.7%, and freedom from moderate or severe mitral regurgitation was 67.5% ± 4.2%. Cox regression analysis revealed that isolated prolapse of the anterior leaflet was predictive of reoperation, and that older age, hypertension, and left ventricular ejection fraction less than 40% were predictive of recurrent moderate or severe mitral regurgitation. Conclusions Chordal replacement with polytetrafluoroethylene sutures expands the indication of repair to patients with prolapse of multiple segments. Valve function remains stable in most patients during the first 2 decades of follow-up.
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long term results of mitral valve repair for myxomatous disease with and without chordal replacement with expanded polytetrafluoroethylene sutures
The Journal of Thoracic and Cardiovascular Surgery, 1998Co-Authors: Tirone E David, Ahmad S Omran, Susan Armstrong, Joan IvanovAbstract:Abstract Objective: This study was carried out to evaluate the long-term results of mitral valve repair for mitral regurgitation caused by myxomatous disease of the mitral valve and the late effects of chordal replacement with expanded polytetrafluoroethylene sutures in this operation. Methods: A total of 324 patients with mitral regurgitation caused by myxomatous disease underwent mitral valve repair from 1981 to 1995; the group comprised 241 men and 83 women whose mean age was 58 ± 14 years. Chordal replacement with expanded polytetrafluoroethylene sutures has been performed in 165 patients since 1985. Most of the patients who had chordal replacement with expanded polytetrafluoroethylene sutures had prolapse of the anterior leaflet or prolapse of both leaflets, whereas most patients who had mitral valve repair without chordal replacement had prolapse of the posterior leaflet. Patients were followed up at annual intervals and had a Doppler echocardiographic study. The follow-up was complete and extended from 6 to 156 months (mean 36 ± 30 months). Results: Two operative and 21 late deaths occurred (14 cardiac and 7 noncardiac). At 10 years the actuarial survival was 75% ± 5%, the freedom from stroke was 94% ± 2%, the freedom from transient ischemic attacks was 92% ± 4%, the freedom from endocarditis was 99% ± 1%, the freedom from mitral valve reoperation was 96% ± 1%, and the freedom from severe mitral regurgitation was 93% ± 3%. Chordal replacement with expanded polytetrafluoroethylene sutures had no effect on any of these end points. Conclusions: Mitral valve repair was feasible in most patients with mitral regurgitation caused by myxomatous disease and it was associated with low rates of valve-related complications. Chordal replacement with expanded polytetrafluoroethylene had no adverse effect on the late outcome and was believed to have increased the probability of mitral valve repair. (J Thorac Cardiovasc Surg 1998;115:1279-86)
Paul J Breslau - One of the best experts on this subject based on the ideXlab platform.
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vein versus polytetrafluoroethylene in above knee femoropopliteal bypass grafting five year results of a randomized controlled trial
Journal of Vascular Surgery, 2003Co-Authors: Pieter Klinkert, Desiree H Burger, Hajo J Van Bockel, Abbey Schepers, Paul J BreslauAbstract:Abstract Objective: Controversy still exists whether polytetrafluoroethylene is equivalent to vein as bypass graft material for the above-knee femoropopliteal bypass. Therefore, a prospective randomized trial was performed to compare vein with polytetrafluoroethylene for femoropopliteal bypasses with the distal anastomosis above the knee. Methods: Between January 1993 and December 1996, 151 above-knee femoropopliteal bypasses were performed. The indications for operation were severe claudication in 120 cases, rest pain in 20 cases, and ulceration in 11 cases. After randomization, 75 reversed saphenous venous bypasses and 76 polytetrafluoroethylene bypasses were performed. Results: No perioperative mortality was seen, and 5% of the patients had minor infections of the wound, not resulting in loss of the bypass, the limb, or life. After 5 years, 38% of the patients had died and 7% were lost to follow-up. Only once was the saphenous vein necessary for coronary artery bypass grafting. Primary patency rates after 5 years were 75.6% for venous bypass grafts and 51.9% for polytetrafluoroethylene grafts ( P =.035). Secondary patency rates were 79.7% for vein and 57.2% for polytetrafluoroethylene bypasses ( P =.036). In the venous group, 14 bypasses failed, leading to five new bypasses. In the polytetrafluoroethylene group, 29 bypasses failed, leading to 16 reinterventions. For these 16 new bypasses, in four cases, the ipsilateral preserved saphenous vein was used. In both groups, one above-knee amputation and one below-knee amputation had to be performed. Conclusion: We conclude after 5 years of follow-up of this randomized controlled trial that a bypass with saphenous vein has better patency rates at all intervals and needs fewer reoperations. Saphenous vein should be the graft material of choice for above-knee femoropopliteal bypasses and should not be preserved for reinterventions. Polytetrafluoroethylene is an acceptable alternative if the saphenous vein is not available. (J Vasc Surg 2003;37:149-55.)
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a prospective randomized trial comparing vein with polytetrafluoroethylene in above knee femoropopliteal bypass grafting
Journal of Vascular Surgery, 2000Co-Authors: Desiree H Burger, Pieter A Kappetein, Hajo J Van Bockel, Paul J BreslauAbstract:bypass graft, a reversed saphenous vein was used in each of 75 cases, and a polytetrafluoroethylene prosthesis was used in each of 76 cases. Preoperative risk factors were diabetes (24%), a history of myocardial infarction (23%), and current status with respect to smoking (74%). There was no hospital mortality; 5% of patients had minor postoperative complications. Results: After 2 years, the primary patency was 83% for saphenous vein and 67% for polytetrafluoroethylene (P = .065); the secondary patency was 83% for saphenous vein and 77% for polytetrafluoroethylene (P = .298). During a follow-up period of 2 years, we found no statistically significant difference in primary and secondary patency between saphenous vein and polytetrafluoroethylene. We found no predictive factor for occlusion of either bypass graft. Conclusion: The use of polytetrafluoroethylene above the knee is a reasonable alternative in femoropopliteal bypass grafting that is associated with acceptable short-term patency rates. (J Vasc Surg 2000;32:278-83.)
Carlos Alberto Braganaa Pereira - One of the best experts on this subject based on the ideXlab platform.
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meta analysis of femoropopliteal bypass grafts for lower extremity arterial insufficiency
Journal of Vascular Surgery, 2006Co-Authors: Carlos Eduardo Pereira, Maximiano Tadeu Villa Albers, Francisco Cardoso Brochadoneto, Marcello Romiti, Carlos Alberto Braganaa PereiraAbstract:BACKGROUND: In femoropopliteal bypass surgery, the use of saphenous vein grafts is preferable, but synthetic grafts are widely used above the knee. The objective of this meta-analysis was to assess the long-term patency of femoropopliteal bypass grafts classified as above-knee polytetrafluoroethylene, above-knee saphenous vein, or below-knee saphenous vein. METHODS: Studies published from 1986 through 2004 were identified from electronic databases and reference lists; 73 articles contributed 1 or more series that used survival analysis, assessed femoropopliteal bypasses in one of the foregoing configurations, reported a 1-year graft patency rate, and included at least 30 bypasses. The series with a predominance of claudicant patients were included in meta-analysis C, and the series in which critical ischemia predominated were included in meta-analysis CI. Pooled survival curves of graft patency were constructed. RESULTS: In meta-analysis C, the pooled primary graft patency was 57.4% for above-knee polytetrafluoroethylene, 77.2% for above-knee vein, and 64.8% for below-knee vein at 5 years; there was a significant difference between above-knee grafts at 3, 4, and 5 years (P .05). In meta-analysis CI, the pooled primary graft patency was 48.3% for above-knee polytetrafluoroethylene, 69.4% for above-knee vein, and 68.9% for below-knee vein at 5 years; there was a significant difference between above-knee grafts until 4 years (P < .05). The corresponding pooled secondary graft patency was 54.0%, 71.9%, and 77.8%, respectively, with a significant difference between above-knee grafts at 2, 3, and 4 years (P < .05). CONCLUSIONS: The great saphenous vein performs better than polytetrafluoroethylene in femoropopliteal bypass grafting and should be used whenever possible.
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meta analysis of femoropopliteal bypass grafts for lower extremity arterial insufficiency
Journal of Vascular Surgery, 2006Co-Authors: Carlos Eduardo Pereira, Maximiano Tadeu Villa Albers, Francisco Cardoso Brochadoneto, Marcello Romiti, Carlos Alberto Braganaa PereiraAbstract:Background In femoropopliteal bypass surgery, the use of saphenous vein grafts is preferable, but synthetic grafts are widely used above the knee. The objective of this meta-analysis was to assess the long-term patency of femoropopliteal bypass grafts classified as above-knee polytetrafluoroethylene, above-knee saphenous vein, or below-knee saphenous vein. Methods Studies published from 1986 through 2004 were identified from electronic databases and reference lists; 73 articles contributed 1 or more series that used survival analysis, assessed femoropopliteal bypasses in one of the foregoing configurations, reported a 1-year graft patency rate, and included at least 30 bypasses. The series with a predominance of claudicant patients were included in meta-analysis C, and the series in which critical ischemia predominated were included in meta-analysis CI. Pooled survival curves of graft patency were constructed. Results In meta-analysis C, the pooled primary graft patency was 57.4% for above-knee polytetrafluoroethylene, 77.2% for above-knee vein, and 64.8% for below-knee vein at 5 years; there was a significant difference between above-knee grafts at 3, 4, and 5 years (P .05). In meta-analysis CI, the pooled primary graft patency was 48.3% for above-knee polytetrafluoroethylene, 69.4% for above-knee vein, and 68.9% for below-knee vein at 5 years; there was a significant difference between above-knee grafts until 4 years (P Conclusions The great saphenous vein performs better than polytetrafluoroethylene in femoropopliteal bypass grafting and should be used whenever possible.
Hideaki Kado - One of the best experts on this subject based on the ideXlab platform.
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modification of expanded polytetrafluoroethylene valved conduit using the thin type leaflets
The Journal of Thoracic and Cardiovascular Surgery, 2018Co-Authors: Yusuke Yamamoto, Takako Miyazaki, Masaaki Yamagishi, Hitoshi Yaku, Satoshi Asada, Yoshinobu Maeda, Hideaki KadoAbstract:Abstract Objectives The expanded polytetrafluoroethylene conduit with fan-shaped leaflets and bulging sinuses for right ventricular outflow tract reconstruction was modified with a newly developed thin-type expanded polytetrafluoroethylene leaflet. The purpose of this study was to evaluate the clinical outcomes and hemodynamic performance of the modified conduit. Methods From January 2010 to December 2013, 149 patients underwent definitive right ventricular outflow tract reconstruction using the expanded polytetrafluoroethylene conduit; the 55 patients receiving a conventional conduit (group N) were compared with the 94 patients receiving a modified conduit (group T). Results There were no conduit-related deaths, operative deaths, or reimplantations for conduit failure. The overall survival and freedom from reintervention for conduit-related reasons at 3 years were 98.2% versus 95.6% ( P = .438) and 94.7% versus 97.9% ( P = .954) for groups N and T, respectively. The mean peak pressure gradients were 22.6 ± 15.6 mm Hg versus 18.2 ± 11.5 mm Hg ( P = .161), and in the subanalysis within small-sized conduits, they were 30.2 ± 16.5 mm Hg versus 20.4 ± 10.7 mm Hg ( P = .034). Regarding conduit insufficiency, the modified conduit showed a significantly worse grade of insufficiency ( P = .014) only in the subanalysis within large-sized conduits. Conclusions Although the clinical outcomes did not differ within midterm observation, the thin-type expanded polytetrafluoroethylene leaflet was considered to be suitable for the small-sized conduits, but not for large-sized conduits, based on the comparison of the hemodynamic performance. Long-term follow-up is necessary to address the appropriate sheet type for middle-sized conduits and to estimate the durability of the thin-type leaflet.
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expanded polytetrafluoroethylene valved conduit and patch with bulging sinuses in right ventricular outflow tract reconstruction
The Journal of Thoracic and Cardiovascular Surgery, 2007Co-Authors: Takako Miyazaki, Masaaki Yamagishi, Toshihide Nakano, Atsuhiro Nakashima, Kouji Fukae, Hitoshi Yaku, Hideaki KadoAbstract:Objectives No specific prosthetic material is currently recognized as being the most suitable for right ventricular outflow tract reconstruction for congenital heart defects. Prosthetic valves are subject to wear and stress because they do not create vortex flow, which helps natural valves to close. We designed a fan-shaped expanded polytetrafluoroethylene valved conduit and patch with bulging sinuses that create vortex flow, making them more reliable over the long term. Methods Bulging sinuses were formed on a sheet of expanded polytetrafluoroethylene using a specially designed mold. Fan-shaped expanded polytetrafluoroethylene sheets (0.1 mm thick) were anastomosed to the edge of the bulging sinuses as valve leaflets, creating monocuspid, bicuspid, or tricuspid valves. These valves were implanted in 157 patients undergoing right ventricular outflow tract reconstruction (age 16 days to 45.4 years, median 2.0 years), in 48 patients as a conduit, and in 109 patients as a patch. Valve function was followed up by echocardiography for 5.6 to 63.7 months (mean 20.8 months). Results There was no mortality or morbidity, and no patients required reoperation during follow-up. No patients had stenosis, and regurgitation was less than mild in all patients with conduits and moderate in 15 patients (13.8%) with patches, but moderate regurgitation did not further develop during follow-up. Valve motion was fully maintained in all patients. Conclusions The expanded polytetrafluoroethylene valved conduits and patches with bulging sinuses showed excellent early-to-midterm results. The valved conduits and patches seem to be promising alternatives to homografts in right ventricular outflow tract reconstruction. Their function will be followed up further.