389例风湿性心脏瓣膜替换术后远期疗效观察

目的 :分析风湿性心脏病瓣膜置换术后远期疗效及其影响因素。方法 :1980年至 2 0 0 0年施行心脏瓣膜置换 4 33例 ,早期死亡 2 7例。术后获访 389例 ,获访时间为 2 16 8病人年 ,平均 5 92病人年。结果 :晚期死亡 35例。晚期死亡率为 1 6 1%病人年。机械瓣和生物瓣晚期死亡率分别为 1 17%和6 10 %病人年 ,15年生存率分别为 89 3%和 4 3 1%。结论 :影响心脏瓣膜置换晚期疗效的主要因素为术前心功、年龄和心房纤颤。机械瓣置换术后晚期死亡原因主要与抗凝有关并发症、心室纤颤、细菌性心内膜炎和心衰有关 ,而生物瓣膜置换术后死亡原因则为生物瓣衰败     

心脏瓣膜置换术后妊娠28例分析

近期，我们对1994年12月～2005年6月我科收治的心脏瓣膜置换术后妊娠患者的临床资料进行回顾性分析。 临床资料；28例心脏瓣膜置换术后妊娠患者，年龄21～31岁;行二尖瓣置换术25例，主动脉瓣置换术1例，三尖瓣置换术2例，置换瓣均为机械瓣；术后心功能Ⅰ～Ⅱ级。     

95例再次人工机械瓣置换术

目的:总结95例再次人工机械瓣置换术的外科治疗经验。方法:自2000年1月至2010年4月共行心脏瓣膜置换术3235例,其中95例行再次人工机械瓣置换术。本组95例第一次手术均是行人工机械瓣置换术后的患者,其中机械瓣功能障碍65例,瓣周漏19例,机械瓣心内膜炎11例,手术均在全麻体外循环心脏停跳下进行,其中急诊手术35例,限期手术20例,择期手术40例。其中二尖瓣置换74例,主动脉瓣置换12例,双瓣置换9例,同期行三尖瓣置换13例,三尖瓣成形45例。结果:围术期死亡7例,病死率7.37%,其中有3例是术中无法脱离体外循环机,2例因术后出现严重低心排出量综合征(低心排)及多脏器功能衰竭死亡,1例死于术后心室颤动(室颤),1例死于术后脑出血、脑疝,其余88例痊愈出院。随访3个月至4年,晚期死亡4例,存活患者心功能均明显改善。结论:掌握好手术时机、手术技术及术后处理,是再次机械瓣置换术成功的重要因素。     

全身麻醉

报导6例再次瓣膜置换术的麻醉处理。4例曾行二尖瓣、主动脉瓣双瓣置换术;2例曾行二尖瓣单瓣置换术。均用生物瓣置换,手术半年停用抗凝药。5例诊断为二尖瓣破裂,1例为主动脉瓣破裂。瓣衰竭是瓣膜置换术后严重并发症之一,血液动力学急骤改变,危及病人生命。本组有8例突然出现症状,其他3例迁延1月到半年。5例心功能     

瓣下结构保留方式对二尖瓣置换术后瓣膜下游湍流剪应力的影响

目的观察瓣下结构保留方式对二尖瓣置换术后猪瓣膜下游湍流剪应力(TSS)的影响。方法滇南小耳猪27只,在全麻气管插管体外循环下行二尖瓣置换术。随机分为A、B、C组,各9只,分别采用单叶机械瓣膜、双叶机械瓣膜和生物瓣膜行二尖瓣置换。每组又分为3个小组,各3只,A1、B1、C1组未保留瓣下结构,A2、B2、C2组保留后瓣瓣下结构,A3、B3、C3组保留全瓣瓣下结构。采用彩色多普勒技术检测各组人工心瓣下游湍流剪应力。结果猪单叶瓣膜置换术后二尖瓣下游两核心区位点TSS组间比较P均>0.05,边界位点TSS组间比较P均<0.05,保留后瓣瓣下结构者高于不保留瓣下结构者,低于全保留瓣下结构者(P均<0.05)。猪双叶瓣膜置换术后、生物瓣膜置换术后二尖瓣下游两核心区位点TSS组间比较P均>0.05,边界位点TSS不保留瓣下结构者和保留后瓣瓣下结构者相比P>0.05,全保留瓣下结构者高于不保留瓣下结构和保留后瓣瓣下结构者(P均<0.05)。结论采用单叶机械瓣行二尖瓣置换术保留后瓣和保留全瓣均可引起跨瓣血流湍流强度增大,且保留全瓣高于保留后瓣者;采用双叶瓣膜和生物瓣膜者,保留后瓣瓣下结构不会导致跨瓣血流湍流强度增大,但保留全瓣可引起跨瓣血流湍流强度增大。     

瓣周漏介入封堵治疗的安全性和有效性

目的 探讨瓣周漏（PVL）介入封堵治疗的安全性和有效性。 方法 采用介入封堵术治疗瓣膜置换术后PVL 42例，既往行单纯二尖瓣瓣膜置换术15例，行单纯主动脉瓣瓣膜置换术13例，行主动脉瓣置换及二尖瓣联合置换术9例，行三尖瓣（功能二尖瓣）置换术2例，二尖瓣置换+冠状动脉旁路移植术3例，并发感染性心内膜炎10例，且术前感染性心内膜炎已得到有效控制。二尖瓣PVL 27例，其中机械瓣置换术后PVL 17例，生物瓣置换术后PVL 10例；主动脉PVL 15例，其中机械瓣置换术后PVL 8例，生物瓣置换术后PVL 7例。行介入封堵治疗PVL，术后随访1~36个月，主要观察患者介入封堵术前术后瓣周反流量、心功能及心室长、横径等的变化，封堵器植入后封堵器位置及对原有人工瓣膜是否存在影响以及并发症情况。 结果 全组除2例患者因手术耐受性较差而未能完成手术，手术成功率95%。总体手术时间（122±30）min，其中数字减影血管造影（DSA）照射时间（20±9）min，住院时间（11±10）d。术后主要并发症包括血红蛋白尿2例（5%），急性肾功能衰竭行连续肾替代治疗治疗1例（2%），输血5例（12%）。心脏超声显示封堵器无移位，患者瓣周反流量减少至（0.5±0.7）ml，（P<0.05），且不影响人工瓣膜功能。 结论 介入封堵方法治疗PVL安全有效，创伤小，恢复快，对于具备适应证的患者应可作为首选治疗方法。      

二尖瓣闭式扩张术后瓣膜置换术临床分析

目的总结二尖瓣闭式扩张术后瓣膜置换术的经验及提高治疗效果的措施.方法分析上海长海医院自2001年8月至2002年7月二尖瓣闭式扩张术后瓣膜置换术34例,二尖瓣闭式扩张术至瓣膜置换术间隔平均时间为4～29(12.5±6.73)年.其中,二尖瓣置换术2例(5.9%),二尖瓣置换 三尖瓣成形术16例(47.1%),二尖瓣置换 主动脉瓣置换术2例(5.9%),二尖瓣、主动脉瓣双瓣置换 三尖瓣成形术14例(41.2%).并与同期风湿性心脏病瓣膜置换术患者有关临床资料对照分析.结果二尖瓣闭式扩张术后瓣膜置换术患者与同期风湿性心脏病瓣膜置换术患者在性别、年龄、心功能、手术方式、体外循环时间、主动脉阻断时间以及手术后早期死亡率等方面比较差异无统计学意义.结论对二尖瓣闭式扩张术后复发或病情加重的患者应尽早行瓣膜置换,加强围手术期合理治疗、有限分离心包粘连、术后加强血流动力学监测、注意心功能支持及呼吸支持等措施,可进一步提高手术效果.     

应用猪主动脉异种瓣作心脏瓣膜置换术的长期经验

作者于1971～1975年间采用戊二醛储存的猪主动脉异常瓣为病人施行心脏瓣膜置换术。其中单纯置换二尖瓣(MVR)者243例,单纯置换主动脉瓣(AVR)者167例,双瓣置换者51例。术后没有常规长时间给抗凝药。AVR、MVR和双瓣置换组手术死亡率分别     

重症心脏瓣膜病的外科治疗(附75例报告)

对75例重症心脏瓣膜病患者施行瓣膜置换术。均采用机械瓣。患者术前心功能Ⅲ级28例,Ⅳ级47例。共行二尖瓣置换术29例．主动脉瓣置换术9例,二尖瓣＋主动脉瓣置换术37例。同时施行三尖瓣成形术62例,左房血栓清除术17例,左房成形术12例,冠状动脉搭桥术4例。术后早期死亡5例。认为良好的术前准备、恰当的手术时机和手术方式．积极防治并发症可提高重症心脏瓣膜病的疗效。     

经导管封堵外科主动脉瓣置换术后瓣周漏的疗效分析研究

目的：探讨经导管封堵外科主动脉瓣置换术后瓣周漏的有效性和安全性。方法：回顾性分析2010年3月至2020年3月在上海交通大学医学院附属胸科医院心内科接受经导管封堵外科主动脉瓣置换术后瓣周漏患者67例,均为外科高危或不愿意接受外科治疗者。分析并总结经导管封堵瓣周漏的手术成功率、住院与随访期间并发症及相关心血管事件的发生情况。结果：67例患者的平均年龄（53.4±22.5）岁,男性占55.2%。其中单纯主动脉瓣置换术28例,主动脉根部带瓣置换术2例,主动脉瓣联合二尖瓣置换术37例。16例置入主动脉生物瓣,余者置入机械金属瓣。中位美国胸外科医师协会死亡风险预测（STS-PROM）评分和欧洲心脏手术风险评估系统（EuroSCORE）Ⅱ评分分别为5.7%(3.1%,9.9%)和7.6%(5.8%,11.7%)。经导管封堵瓣周漏成功率为83.6%(56/67),1年生存率为98.5%。住院期间发生的与瓣周漏封堵主要相关事件为术后溶血,发生率为14.9%(10/67),1例因溶血进行性加重致急性肝肾功能衰竭死亡;另1例因主动脉瓣周置入封堵器后影响左心室流出道,转外科手术。平均随访（13.0±0.8）...     

Experience with the selective use of the Carpentier-Edwards bioprosthesis

Between April, 1977, and November 1984, 136 porcine bioprosthetic valves were implanted in 122 patients principally selected on the basis of age and contraindication to anticoagulants. The following procedures were carried out: aortic valve replacement (AVR) 88, pulmonary valve replacement (PVR) 1, mitral valve replacement (MVR) 38, and tricuspid valve replacement (TVR) 9. The ages ranged from 25 to 84 years (mean 64.6 years). The 30-day mortality was 11.5% overall. Survivors were followed up to 7 years (mean 29.2 months). Actuarial survival rates at 5 years, including operative deaths, were as follows: AVR 76.2 +/- 9.3%, MVR 59.7 +/- 12.6% and combined valve replacement (CVR) 47.1 +/- 19.4%. The 5-year probability of freedom from valve-related complications was 76.8 +/- 6.9% for all patients. The rate of thromboembolic events was 3.80% per patient-year after AVR and 2.72% per patient-year after MVR and CVR. The embolic rate did not differ between patients treated with anticoagulants and those treated with platelet antiaggregators. Primary tissue valve failure occurred in 2 patients for a linear incidence of 0.77% per patient-year. Postoperative echocardiography was performed in 83% of the survivors. Patients are now prospectively followed up by bidimensional echography and pulsed Doppler in order to detect early valvular dysfunction. The performance of the Carpentier-Edwards porcine bioprosthesis is, thus, satisfactory in this group of elderly patients.     

环氧氯丙烷对猪主动脉瓣膜去细胞基质体外酶解影响

目的:研究环氧氯丙烷对猪主动脉瓣膜去细胞基质体外降解的影响。方法:按实验干预不同,将90个去细胞猪瓣叶随机分为:胶原酶和弹性蛋白酶组(A组),环氧氯丙烷组(B组),水解对照组(C组)。A组将猪主动脉瓣膜去细胞基质,采用0.5%胶原酶和弹性蛋白酶降解;B组采用0.2%环氧氯丙烷预处理后48h,再应用0.5%胶原酶Ⅰ和弹性蛋白酶体外降解猪主动脉瓣膜去细胞基质;C组加入蒸馏水处理;于处理后第3、6、9、15和30天观察各组降解失重率、降解液外观、蛋白及羟脯氨酸含量。结果:A、B组的支架材料均随降解时间延长逐渐变得菲薄、组织疏松,降解液外观变浑浊,瓣膜失重率增加,降解液蛋白含量和羟脯氨酸含量增加(P<0.01);B组和A组相比在瓣膜失重率,降解液蛋白含量和羟脯氨酸含量均明显减低,但2组上述指标均高于C组(P<0.01)。结论:环氧氯丙烷有减缓胶原酶和弹性蛋白酶降解猪主动脉瓣膜去细胞基质的作用。     

Double mitral and aortic valve replacement: 322 cases operated on between 1970 and 1985

Over this 15-year period, 322 combined aortic and mitral valve replacements were performed by the same surgeon. Bioprostheses were used in only 4 patients, 318 received a double mechanical prosthesis. The Bjork-Shiley valve was always used for the aortic orifice. For the mitral orifice, three types of valve were implanted: 160 Starr-Edwards 6120 valves, 59 Bjork-Shiley valves and 99 St-Jude Medical valves. The early post-operative mortality was 5.9 p. 100. It was due to cardiac causes in 73.7 p. 100 of the cases and was significantly influenced by the myocardial protection technique (p less than 0.05). A long-term review of the survivors was carried out in november-december, 1986: 15 patients were lost sight of; there were 63 late deaths 77.8 p. 100 of which were either of cardiac origin or due to the prosthesis. 225 patients have survived with a mean follow-up of 79.1 months. The actuarial survival rate (early post-operative mortality included) was 78.2 p. 100 at 5 years and 70.2 p. 100 at 10 years. The incidence of peripheral arterial embolism was 1.9 p. 100 per patient-year, while that of all thromboembolic complications (sudden deaths included) was 3.4 p. 100 per patient-year. The percentages per patient-year of the other complications observed were: haemorrhages 2.2 p. 100, infective endocarditis 0.40 p. 100, reoperation 0.47 p. 100. The proportions of patients free of any complication were 84.8 p. 100 at 5 years and 79.7 p. 100 after 10 years.(ABSTRACT TRUNCATED AT 250 WORDS)     

A 12-year clinical experience of cardiac valve replacement with domestic tilting disc valve prostheses in 1013 cases]

1013 patients with cardiac valve replacement during a 12-year period from 1978 to 1990 were reported. 566 cases were implanted with Shanghai-made tilting disc valve prostheses and 447 with Lanzhou-made (C-L valves). Mitral valve replacement (MVR) in 753 patients, aortic valve replacement (AVR) in 102 and double valves replacement (DVR) in 158. The overall early mortality rate was 6.2% with 4.9%, 7.8% and 11.3% after MVR, AVR and DVR respectively. Follow-up study was made in 3097.43 patient-year (mean 3.26 years). The late death rate was 1.6% patient-years and with 1.4, 1.8 and 3.2 after MVR, AVR and DVR respectively. The incidence of late valve-related complication (% patient-years) were: thromboembolism 0.39, anticoagulant-related hemorrhages 0.77, prostheses failure 0.22, prosthetic valve endocarditis 0.38, periprosthetic leak 0.12, and reoperations 0.38. The domestic tilting disc valve prostheses are considered to be qualified valves with low mortality and satisfactory results.     

Carpentier-Edwards porcine bioprostheses: assessment of clinical performance

Carpentier-Edwards porcine bioprostheses have been implanted since 1975, commencing with the previous generation standard prosthesis in that year and the new generation supra-annular prosthesis in 1981. The first 700 operations with each prosthesis were evaluated: Carpentier-Edwards standard porcine bioprosthesis (CE-S), 692 patients (772 valves) and Carpentier-Edwards supra-annular porcine bioprosthesis (CE-SA), 698 patients (756 valves). The incidence of thromboembolism was CE-S 1.4% per patient-year and CE-SA 2.1% per patient-year (hazard interval rates not considered). The rate of structural valve deterioration was CE-S 1.8% per patient-year (79 prostheses) and CE-SA 0.2% (four prostheses). The reoperation rate was 2.5% per patient-year (110 prostheses) for CE-S and for CE-SA it was 0.9% (six prostheses). The late mortality rate was 3.7% per patient-year and 4.2%, respectively. The 10-year freedom rates for CE-S were thromboembolism, 82.7 +/- 2.8%; prosthetic valve endocarditis, 93.5 +/- 1.6%; structural valve deterioration, 77.1 +/- 2.9%; reoperation, 69.9 +/- 3.1%; valve related mortality, 85.9 +/- 2.4%; valve failure, 62.8 +/- 3.2%; treatment failure, 82.0 +/- 2.7%; mortality, reoperation and residual morbidity, 59.5 +/- 3.2%; and all complications, 53.4 +/- 3.1%. The four-year freedom rates for CE-SA were thromboembolism, 93.0 +/- 1.3%; prosthetic valve endocarditis, 98.7 +/- 0.5%; structural valve deterioration, 98.3 +/- 1.0%; reoperation, 95.6 +/- 1.3%; mortality, 97.9 +/- 0.6%; valve failure, 93.6 +/- 1.4%; treatment failure, 94.6 +/- 1.1%; mortality, reoperation and residual morbidity, 90.9 +/- 1.6%; and all complications, 85.6 +/- 1.9%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term results of valve replacement using the Cobomedics prosthesis

The Carbomedics valve prosthesis is a second generation mechanical prosthesis with a double hemi-disc. This study analysed long-term morbidity and mortality associated with this prosthesis. Between 1987 and 1996, 397 prostheses were implanted, 306 aortic, 42 mitral and 26 double replacements (3 combining a Carbomedics aortic prothesis with a mitral valve from another type) in 370 patients with a mean age of 62 (range 4 to 88 years). The global operative mortality was 7.4%. A questionnaire sent to treating cardiologists, general practitioners and patients updated the prospective data base of the cardiac surgical department. The follow-up was 99%, representing a total of 1244 patient-years with an average of 41 months (range 1.1 month to 9.9 years). The 1, 3, 5 and 7 year survival (operative mortality included) was 88%, 80%, 76% and 69.6% respectively. Haemorrhagic complications were the most common (17 cases, 1.36% per patient-year) and 11 thromboembolic episodes were observed (0.88% per patient-year) with a higher incidence (p < 10-4) in mitral valve replacement (3.8% in patient-year). The other complications observed were: 5 aseptic paravalvular leaks (0.4% per patient-year) and 5 prosthetic valve infections; no structural alterations were observed. In all, ten reoperations (0.8% per patient-year) were required for prosthetic valve complications. This study shows the reliability of Carbomedics valve prostheses with a low complication rate comparable to that of other modern mechanical valve prostheses.     

Thromboembolic and bleeding complications following St. Jude Medical valve replacement: results of the German Experience With Low-Intensity Anticoagulation Study

STUDY OBJECTIVES: Due to their inherent thrombogenicity, mechanical cardiac valves necessitate lifelong oral anticoagulation. Less intensive oral anticoagulation than recommended earlier might result in a lower incidence of bleeding complications without increasing the embolic hazard significantly. DESIGN: Comparison of three different intensities of oral anticoagulation in a prospective, randomized multicenter design. Three months after valve replacement, patients were randomly assigned to stratum A, international normalized ratio (INR) 3.0 to 4.5; stratum B, INR 2.5 to 4.0; or stratum C, INR 2.0 to 3.5. PATIENTS: Data from 2,735 patients following aortic valve replacement (AVR; n = 2,024), mitral valve replacement (MVR; n = 553), and combined AVR and MVR (n = 158) with the St. Jude Medical (SJM) valve (St. Jude Medical; St. Paul, MN) between July 1993 and May 1999 were analyzed, covering a total follow-up period of 6,801 patient-years. All complications were registered prospectively. MEASUREMENTS AND RESULTS: Fifty-one thromboembolic events (TEs) were documented, resulting in a linearized incidence of 0.75 TEs per 100 patient-years, 22 of which were minor (0.32% per patient-year), 10 were moderate (0.15% per patient-year), and 19 were severe (0.28% per patient-year). Thromboembolism following AVR was significantly lower than after MVR (0.53% per patient-year vs 1.64% per patient-year). Patients reported 1,687 bleeding complications (24.8% per patient-year). The vast majority of bleeding complications (n = 1,509; 22.2% per patient-year) were classified as minor, 140 were classified as moderate (2.06% per patient-year), and 38 were classified as severe (0.56% per patient-year). The clinically relevant incidences of moderate and severe TEs and bleeding complications were not significantly different between the three prespecified INR strata. CONCLUSIONS: The intention-to-treat analysis of the results of the German Experience With Low Intensity Anticoagulation study leads to the unexpected result that despite a sophisticated reporting system, the incidence of moderate and severe TE and bleeding complications was comparably low in all INR strata and more or less within the so-called background incidence reported for an age-related "normal" population. This study supports reexamination of the intensity of anticoagulation in patients with the SJM valve.     

The St. Jude valve prosthesis: analysis of the clinical results in 815 implants and the need for systemic anticoagulation

Between July 1979 and December 1984, 785 patients received 815 St. Jude Medical valve prostheses. Valve-related mortality in the follow-up period was due to thromboembolism in seven cases, anticoagulant-related hemorrhage in three and perivalvular leak in two. Freedom from valve-related death or reoperation at 3 years was 96.4% for aortic valve replacement and 98.3% for mitral valve replacement. The overall rate of thromboembolism was 2.6%/patient-year with warfarin, 9.2%/patient-year with antiplatelet medication and 15.6%/patient-year in patients with no anticoagulant therapy. One episode of thrombotic obstruction of a mitral valve, in a patient receiving no anticoagulant therapy, resulted in an occurrence rate of such obstruction of 0.22%/patient-year. Valve replacement with the St. Jude valve produced excellent clinical results, but long-term anticoagulation with warfarin was required to minimize thromboembolic complications. The use of antiplatelet agents alone provided inadequate protection.     

Surgical treatment of active infective aortic valve endocarditis with associated periannular abscess--11 year results.

AIMS: The aim of the study was to evaluate the long-term results of allograft and prosthetic valve replacement in the treatment of infective aortic valve endocarditis with periannular abscess. METHODS: Between March 1988 and March 1996, 65 patients underwent surgery for active aortic valve endocarditis and paravalvular abscess. The indications for surgery were congestive heart failure, systemic emboli and atrioventricular block III. The pre-operative evaluation was performed with transoesophageal echocardiography. Aortic valve replacement was performed with allografts in 47 cases, with mechanical valves in 15, and bioprosthetic valves in three cases. All patients with total ventricular-aortic dehiscence and prosthetic valve endocarditis were treated with allografts. RESULTS: The 30-day mortality rate was 23.5% in the prosthetic group, when compared with 8.5% in the patients treated with allografts. The rate of recurrent valve infections during the 11-year follow-up period was 27.1% in the prosthetic group and 3.2% in the allograft group. The actuarial 11-year survival rate was 82.1% in the allograft group and 64.7% in the prosthetic group. CONCLUSION: Aortic allografts are an effective treatment for infective aortic valve endocarditis with associated periannular abscess. The operative mortality and recurrent infection rates are lower than in the prosthetic group, resulting in a significantly higher survival rate. Diagnosis and surgical management of these cases should be based on pre-operative transoesophageal echocardiography.     

Valve surgery in renal dialysis patients

BACKGROUND AND AIM OF THE STUDY: Mechanical valves are used in dialysis patients due to the presumed rapid degeneration of tissue valves. The study aim was to compare the results of mechanical and tissue valves placed in renal dialysis patients. METHODS: Information obtained from a computer-based valve replacement database, telephone interviews and patient charts was reviewed for follow up data. RESULTS: Between 1991 and 2004, 50 dialysis patients underwent left-sided valve replacement. Of these patients, 17 received 21 St. Jude Medical mechanical valves (12 aortic, nine mitral), and 33 received 39 tissue valves (19 aortic, 20 mitral). The mean follow up for the mechanical and tissue valve groups was 19.4 +/- 21.3 and 21.4 +/- 18.7 months, respectively. Mortality at four years was 65% (11/17) for the mechanical valve group, and 42% (14/33) for the tissue valve group (p = 0.15). Freedom from reoperation was not significantly different. The tissue valve group had significantly higher Kaplan-Meier freedom from thromboembolism (100% versus 75 +/- 15%, p = 0.01), hemorrhage (97 +/- 3% versus 44 +/- 17%, p = 0.002), valve-related morbidity (74 +/- 9% versus 42 +/- 16%, p = 0.043), and valve-related morbidity and mortality (69 +/- 9% versus 37 +/- 14%, p = 0.037) at three years. Linearized rates of hemorrhage (21 versus 2%/pt-yr; p = 0.005), valve-related morbidity (36 versus 12%/pt-yr; p = 0.02) and valve-related morbidity and mortality (50 versus 17%/pt-yr; p = 0.008) were all significantly higher in the mechanical valve group. CONCLUSION: Dialysis patients had poor survival; prosthetic valve degeneration was negligible. Incidences of thromboembolism, bleeding and valve-related morbidity and mortality were higher with mechanical valves. Linearized, as opposed to actuarial, analysis further accentuated the unacceptably high rates of complications and death with mechanical valves.