Incidence and risk factors of prosthetic valve endocarditis

To study the incidence and risk factors of prosthetic valve endocarditis (PVE) we followed 99.5% of 912 patients who had valve replacements from 1 January 1981 to 31 December 1985 for 1-6 (mean 3) years. PVE occurred in 27 patients (2.96% or 0.98% per patient-year). The incidence of PVE in the aortic position (3.9%) was significantly higher than in the mitral position (1.5%): chi-square = 6.1, P less than 0.025. PVE developed in 19 of 329 patients with bioprostheses (5.8%), and in 8 of 583 patients with mechanical valves (1.4%): chi-square = 14.48, P less than 0.005). Actuarially at 5-year follow-up, 90.7% +/- 2.16% of the bioprosthetic group and 98.4% +/- 0.56% of the mechanical valve group was free of PVE (P less than 0.001). Antecedent endocarditis increased both the incidence and relative risk of PVE 7-fold compared to patients without antecedent endocarditis (chi-square = 32.0, P less than 0.0001). Bioprosthetic valve replacement in infective endocarditis increased the risk of PVE 12-fold compared to valve replacement by mechanical prostheses. In conclusion: in the order of importance, antecedent endocarditis, bioprostheses and aortic position are risk factors in the development of PVE. Bioprostheses implanted in patients with antecedent endocarditis further enhance the risk of PVE.     

Prosthetic replacement of tricuspid valve: bioprosthetic or mechanical

BACKGROUND: Tricuspid valve replacement is one of the most challenging operations in cardiac surgery. Selection of the suitable prosthesis is still debatable. METHODS: In our institution, between January 1980 and December 2000, 129 tricuspid valve replacements were performed in 122 patients (14.7%). Bioprosthetic valves were used in 32 patients, whereas 97 patients had mechanical valve implantation. Twenty-two percent of replacements were done on men. Mean age was 35.27+/-11.56 years. In all patients, initially an annuloplasty technique was tried. Tricuspid valve replacement was performed when annuloplasty was not sufficient. In most of the cases, tricuspid valve interventions were done under cardiopulmonary bypass and on a beating heart. RESULTS: Early mortality was 24.5%. Patients were followed for 2 to 228 months. Seven patients underwent reoperation because of tricuspid valve dysfunction (7.6%). Nine patients died during the follow-up period. Late mortality was 9.7%. Actuarial estimates of survival in 20 years of follow-up for all tricuspid prosthetic valves, mechanical valves, and bioprosthetic valves were 65.1%+/-9.3%, 68.3%+/-10.6%, and 54.8%+/-12.1%, respectively. For the bioprosthetic valve group, freedom from structural valve degeneration was 90%+/-5.5%; for the mechanical valve group, freedom from deterioration, endocarditis, and leakage was 97.8%+/-4.2%, and freedom from thromboembolism was 92.6%+/-6.9%. CONCLUSIONS: We found that there was no statistically significant difference between the two groups in terms of early mortality, re-replacement, and midterm mortality (p > 0.05). Nevertheless, we recommend low profile modern bileaflet mechanical valves for prosthetic replacement of the tricuspid valve, due to their favorable hemodynamic characteristics and durability.     

Valve-related complications with the Hancock I porcine bioprosthesis. A twelve- to fourteen-year follow-up study

Valve-related morbidity and mortality after heart valve replacement with the Hancock I porcine bioprosthesis has been retrospectively analyzed. From June 1974 through December 1976, 253 Hancock I bioprostheses (150 mitral and 103 aortic) were inserted in 220 selected patients who survived the operation and had follow-up until June 1989 (mean follow-up 13.5 years, with an accumulative follow-up of 2956.4 patient-years). One hundred seventeen patients had mitral valve replacement, 70 had aortic valve replacement, and 33 had combined mitral and aortic valve replacement. There were 27 thromboembolic events. The probability of being free from thromboembolism at 14 years was 81.0% +/- 7.4% for the mitral valve replacement group, 85.4% +/- 6.7% for the aortic group, and 67.1% +/- 18.4% for the mitral-aortic group. Fifteen episodes of prosthetic valve endocarditis occurred. There were 10 instances of nonstructural dysfunction (paravalvular leaks) in seven mitral valves (4.6%) and in three aortic valves (2.9%). One hundred twenty-two bioprostheses in 106 patients resulted in structural deterioration. The probability of freedom from structural deterioration at 14 years was 37.2% +/- 3.9% for the mitral group, 43.9% +/- 7.1% for the aortic group, and 30.1% +/- 8.9% for the mitral-aortic group. The logistic regression analysis between age at the time of operation and bioprosthetic life (structural deterioration-free period) demonstrates a linear regression curve (r = 0.53). There were 56 late deaths (27 patients died at reoperation). The actuarial survival rate (including hospital mortality) at 14 years was 57.2% +/- 5.4% for the entire series, with no statistically significant difference between groups. The probability of remaining free from valve-related morbidity and mortality at 14 years was 16.7% +/- 4.8% for the mitral group, 20.8% +/- 6.2% for the aortic group, and 14.0% +/- 7.0% for the mitral-aortic group. The long-term results of this series show that the clinical performance of the Hancock I porcine valve appears satisfactory during the first 6 years. The behavior of this bioprosthesis at 14 years' follow-up changes drastically, because only a minor group of patients is free from valve-related complications, justifying the restriction of its use for selected patients.     

Actuarial analysis of the risk of prosthetic valve endocarditis in 1,598 patients with mechanical and bioprosthetic valves

We reviewed the charts of 1,598 patients undergoing valve replacement at the National Institutes of Health, Bethesda, Md, from 1956 through 1981. Retrospective analysis disclosed that 43 patients had prosthetic valve endocarditis (PVE). Twelve patients had early (less than 60 days after operation) and 31 patients had late (greater than 60 days after operation) endocarditis. The cumulative risk was 3% at five years and 5% at ten years. We also calculated the interval risk of PVE. The high risk of early PVE development peaked 15 days after operation. The peak risk was 45 episodes per 100,000 patient days. The risk then declined rapidly and from 150 days to 20 years remained stable at approximately one episode per 100,000 patient days. Nine hundred fifty-two patients had valve replacement with a Starr-Edwards prosthesis and 363 patients had valve replacement with a bioprosthetic valve; there was no significant difference in the risk of PVE in either group. Neither the valve make, position, model, nor the number of valves implanted affected the frequency of PVE or the mortality. Actuarial techniques disclosed the high early risk of PVE, the prolonged risk of PVE up to 150 days after operation, and the low but persistent risk late after operation. There was no significant difference in the risk of PVE in patients with bioprosthetic v mechanical valves.     

An eight-year experience with porcine bioprosthetic cardiac valves

A total of 589 porcine bioprostheses were implanted in 509 patients from January, 1976, through December, 1983. Of the valves implanted, 390 were Hancock and 199 were Carpentier-Edwards. A total of 1,633 patient-years was accrued, with a mean follow-up of 38 months per patient. Two hundred eight patients had aortic valve replacement, 209 had mitral valve replacement, and 79 had multiple valve replacements, of which 46 were aortic and mitral replacements. The mortality for isolated aortic valve replacement was 5.8%; for isolated mitral replacement, 8.6%, and for all patients, 10.9%. Late mortality was 3.9% per patient-year. The actuarial survival rate at 5 years was 79% for aortic, 68% for mitral, and 76% for aortic-mitral valve replacement. There were 12 thromboembolic events (0.73% per patient-year). Two episodes occurred in patients with an aortic bioprosthesis, nine in patients with a porcine mitral valve, and one in a patient with mitral and tricuspid bioprosthetic valves. The probability of remaining free of thromboembolism at 5 years was 99% for the group having aortic valve replacement, 93% for those having mitral replacement, and 100% for the group having aortic-mitral valve replacements. Thirteen episodes of endocarditis occurred (0.8% per patient-year). Seven of the 13 patients died as a direct result of endocarditis. The probability of remaining free of prosthetic endocarditis at 5 years was 97% for the aortic valve replacement group, 95% for the mitral group, and 97% for the aortic-mitral group. There were 20 instances of xenograft failure (1.2% per patient-year). The probability of remaining free of valve failure at 5 years was 96% for the aortic valve replacement group, 93% for the mitral group, and 93% for the aortic-mitral replacement group. Primary tissue failure of a prosthesis occurred in seven patients, all with Hancock valves (0.43% per patient-year). As yet there has been no primary tissue failure of the Carpentier-Edwards prosthesis. There also appears to be a lower incidence of thromboembolism (Edwards, 0.3% per patient-year; Hancock, 0.8% per patient-year) and endocarditis (Edwards, 0.6% per patient-year; Hancock, 1.0% per patient-year). The low incidence of complications with the porcine bioprosthetic valve, especially the Carpentier-Edwards, encourages us to recommend its continued use, especially in situations in which anticoagulation is contraindicated.     

Comparative analysis of mechanical and bioprosthetic valves after aortic valve replacement

Comparative long-term performance characteristics of Bj?rk-Shiley mechanical and bioprosthetic valves were analyzed for patients undergoing aortic valve replacement between 1976 and 1981. A total of 419 patients received either a standard Bj?rk-Shiley (n = 266) or bioprosthetic (porcine, n = 126, or pericardial, n = 27) aortic valve. Cumulative patient follow-up was 1,705 patient-years; the average patient follow-up was 4.1 +/- 2.7 years. Survival data were obtained for all but 11 patients (97% complete follow-up) up to 9 years after operation. Survival at 5 years was 81% +/- 4% (+/- standard error) for Bj?rk-Shiley and for bioprosthetic valve recipients. Valve failure in the Bj?rk-Shiley group was predominantly due to valve-related mortality and did not result from structural failure. Patients with bioprosthetic valves experienced valve failure as a result of prosthetic valve endocarditis and intrinsic valve degeneration. Although patients with bioprostheses experienced a lower incidence of valve-related morbidity than Bj?rk-Shiley valve recipients (p less than 0.03), no difference could be demonstrated in the incidence of valve-related mortality or valve failure at 5 years between bioprosthetic and Bj?rk-Shiley valves. Mortality rate from valve failure was higher for Bj?rk-Shiley (86%, 12/14) than bioprosthetic valves (36%, 5/14) (p less than 0.01).     

Fifteen-year clinical experience with the biocor porcine bioprostheses in the mitral position

BACKGROUND: Bioprosthetic valve use represents a crucial improvement in surgical treatment of mitral valve disease. The aim of this study is to determine the long-term durability of the Biocor porcine bioprosthetic mitral valve. METHODS: Between 1985 and 1989, a total of 158 Biocor porcine bioprosthetic valves were placed in the mitral position, and long-term results of these patients were investigated retrospectively in 1999. RESULTS: Thirty-day mortality was 4.4% (7 patients). Total follow-up was 1,499 patient-years. Actuarial survival was 83.66% +/- 3% at 5 years, 77.78% +/- 3.36% at 13 years (1.8% patient-year). Multivariate analysis demonstrated younger age, duration of implantation, congestive heart failure, and functional class to be significant predictors of late mortality. Actuarial freedom from valve-related mortality was 98.58% +/- 1% at 15 years (0.13% patient-year). Actuarial freedom from structural valve deterioration was 95.49% +/- 1.8% at 5 years, 70.2% +/- 4.12% at 10 years, and 64.82% +/- 5.34% at 13 years (2.6% patient-year). Actuarial freedom from structural valve deterioration-related reoperation was 98.43% +/- 1.1% at 5 years, 89.15% +/- 2.85% at 10 years, and 76.82% +/- 7.91% at 14 years. Multivariate analysis showed younger age and duration of implantation to be significant predictors of structural valve deterioration and its related reoperation. CONCLUSIONS: By studying a 15-year time period, it is seen that this new generation porcine bioprosthetic valve should be considered an alternative for mechanical valves in selected patients.     

Long-term performance of porcine heart valve bioprostheses

To assess the results after long-term implantation of porcine bioprosthetic heart valves, 320 patients with 381 valves were retrospectively reviewed. This group included all patients receiving one such xenograft in the mitral or aortic position (or both) in our institution between June 1974 and December 1976. The patients had a follow-up of 9-11.5 years. Actuarial patient survival rats (hospital mortality excluded) were 85%-90% at 6 years and 68%-79% at 11.5 years. Thromboembolic episodes did not show any significant clustering over the first weeks or months, in fact, they appeared at a constant rate. Actuarial rates of freedom from thromboembolism were greater than 90% for aortic patients at 11.5 years and greater than 80% for mitral and mitroaortic patients at 11.5 years. The linearized rate of anticoagulant-related haemorrhage for the whole group of patients was 0.4 events/100 patient years with a related mortality of 0.2 events/100 patient years. Prosthetic valve endocarditis and paravalvular leak appeared at linearized rates of 0.6 (0.1 of related mortality) and 0.4 (0.1 of related mortality) events/100 patient years. Primary tissue valve failure constituted the most prevalent complication (82 cases) in the long term but did not significantly worsen patient survival. Actuarial rates of freedom from primary tissue failure were 91% +/- 2% at 6, and 40% +/- 14% at 11.5 years for mitral valves, and 95% +/- 4% at 6 and 64% +/- 6% at 11.5 years for aortic valves.(ABSTRACT TRUNCATED AT 250 WORDS)     

More than ten years' follow-up of the Hancock porcine bioprosthesis in Japan.

From February 1975 through October 1981, 256 Hancock porcine bioprostheses (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) (60 aortic, 169 mitral, and 27 pulmonary/tricuspid position) were implanted in 220 patients (104 male and 116 female, aged 9 to 67 years; mean 43.3) at Kyushu University Hospital in Japan. The procedures include 41 aortic valve replacements, 121 mitral valve replacements, 4 pulmonary valve replacements, 6 tricuspid valve replacements, and 48 combined valve replacements (31 aortic plus mitral, 13 mitral plus tricuspid, and 4 aortic plus mitral plus tricuspid). Hospital mortality was 6.4%. Follow-up was 98% during 8 to 14 (mean 10.5) years. Cumulative follow-up was 1836 patient-years and 2078 valve-years. At 10 years the overall actuarial survival rate, including hospital morality, was 70% +/- 3%, and freedom from valve-related mortality with sudden death was 87% +/- 3%. More than half of the current survivors required no anticoagulant therapy. Freedom from thromboembolism or anticoagulant-related hemorrhage (or both) and prosthetic valve endocarditis was common. Freedom from structural valve failure and reoperation declined more than 9 years after replacement of left-sided heart valves but not after replacement of right-sided heart valves. Sixty-seven patients underwent 68 repeat operations, and there were four deaths (5.9%). The rate of freedom from overall valve-related complications at 10 years was 62% +/- 8% for aortic valve replacement, 53% +/- 5% for mitral valve replacement, 80% +/- 13% for pulmonary/tricuspid valve replacement, and 42% +/- 9% for combined valve replacement. There was a significant difference between pulmonary/tricuspid valve replacement and combined valve replacement (p less than 0.05). The Hancock bioprosthesis is suitable for the replacement of valves in the right side of the heart but not for combined valve replacement.     

Twenty-year comparison of tissue and mechanical valve replacement

OBJECTIVE: We sought to compare outcomes with tissue and St Jude Medical mechanical valves over a 20-year period. METHODS: Valve-related events and overall survival were analyzed in 2533 patients 18 years of age or older undergoing initial aortic, mitral, or combined aortic and mitral (double) valve replacement with a tissue valve (Hancock, Carpentier-Edwards porcine, or Carpentier-Edwards pericardial) or a St Jude Medical mechanical valve. Total follow-up was 13,390 patient-years. There were 666 St Jude Medical aortic valve replacements, 723 tissue aortic valve replacements, 513 St Jude Medical mitral valve replacements, 402 tissue mitral valve replacements, 161 St Jude Medical double valve replacements, and 68 tissue double valve replacements. The mean age was 68 +/- 13.3 years (St Jude Medical valve, 64.5 +/- 12.9; tissue valve, 72.0 +/- 12.6). RESULTS: There were no overall differences in survival between tissue and mechanical valves. Multivariable analysis indicated that the type of valve did not affect survival. Analysis by age less than 65 years or 65 years or older and presence or absence of coronary disease revealed similar long-term survival in all subgroups. The risk of hemorrhage was lower in patients receiving tissue aortic valve replacements but was not significantly different in patients receiving mitral valve or double valve replacements. Thromboembolism rates were similar for tissue and mechanical valve recipients. However, reoperation rates were significantly higher in patients receiving both aortic and mitral tissue valves. The reoperation hazard increased progressively with time both in patients receiving aortic and in those receiving mitral tissue valves. Overall valve complications were initially higher with mechanical aortic valves but not with mechanical mitral valves. However, valve complication rates later crossed over, with higher rates in tissue valve recipients after 7 years in patients undergoing mitral valve replacement and 10 years in those undergoing aortic valve replacement. CONCLUSIONS: Tissue and mechanical valve recipients have similar survival over 20 years of follow-up. The primary tradeoff is an increased risk of hemorrhage in patients receiving mechanical aortic valve replacements and an increased risk of late reoperation in all patients receiving tissue valve replacements. The risk of tissue valve reoperation increases progressively with time.     

The porcine bioprosthetic valve. Twelve years later

The porcine bioprosthetic heart valve has been commercially available since 1970 and has been the prosthetic heart valve of choice in our institution since 1971. Since that time 817 patients with 951 porcine valves have been discharged from the hospital and were available for long-term follow-up. Patient survival rates, with operative mortality excluded, were 80% +/- 1.7% (standard error) at 5 years and 68% +/- 2.7% at 10 years. Survival rates for patients with aortic valve prostheses were 78% +/- 2.8% at 5 years and 57% +/- 5.4% at 10 years; for patients with mitral valve prostheses, survival rates were 80% +/- 2.2% at 5 years and 69% +/- 3.2% at 10 years. Freedom from thromboembolism for aortic valves was 93% +/- 1.4% at 5 years and 88% +/- 2.6% at 10 years; for mitral valves the freedom from degeneration or primary tissue failure for aortic valves was 97% +/- 1.3% at 5 years and 71% +/- 7.6% at 10 years; for mitral valves these figures were 96% +/- 1.2% at 5 years and 71% +/- 4.1% at 10 years. Valves in patients 35 years of age and below had a significantly greater rate of degeneration (p less than 0.001). After 12 years' experience the porcine bioprosthetic valve has performed well with regard to patient survival and low rate of thromboembolism. For patients older than 35 years the freedom from primary tissue failure is 80% at 10 years.     

Tricuspid valve replacement: an analysis of 25 years of experience at a single center

BACKGROUND: Tricuspid valve replacement is seldom used in clinical practice, but the choice between mechanical and biologic prostheses remains controversial. METHODS: Between 1977 and 2002, 97 patients underwent tricuspid valve replacement and were followed at the Montreal Heart Institute Valve Clinic. Patients underwent replacement with bioprostheses (n = 82) and mechanical valves (n = 15). RESULTS: Patients with bioprosthetic tricuspid replacements averaged 53 +/- 13 years of age compared with 48 +/- 11 years in those with tricuspid mechanical valve replacements (p = 0.2). Isolated tricuspid valve replacement was performed in 11 patients (73%) in the mechanical valve group compared with 31 patients (38%. p = 0.01) in the bioprosthetic replacement group. In patients undergoing bioprosthetic tricuspid replacement, 51 (62%) underwent multiple associated valve replacements. The 5-year survival after tricuspid replacement averaged 60% +/- 13% in the mechanical valve group and 56% +/- 6% in the biologic replacement group (p = 0.8). The 5-year freedom rate from tricuspid valve reoperation averaged 91% +/- 9% in patients with mechanical valves and 97% +/- 3% in those with biologic valves (p = 0.2). CONCLUSIONS; Patient survival after tricuspid valve replacement is suboptimal but related to the clinical condition at operation. The use of biologic prostheses for tricuspid valve replacement remains a good option in young patients because of limited life expectancy unrelated to the type of tricuspid prostheses at long-term follow-up.     

Long-term results of valve replacement in the right side of the heart in congenital heart disease--comparative study of bioprosthetic valve and mechanical valve

Valve replacements in the right side of the heart (TVR and PVR) were done on 16 patients with congenital heart disease, mainly tetralogy of Fallot and Ebstein anomaly. Including reoperations, 19 operations were performed on them and 20 artificial valves were inserted. Ten mechanical valves (7 St. Jude Medical valves, 3 Starr-Edwards valves) and 10 bioprosthetic valves (7 Carpentier-Edwards valves, 3 Ionescu-Shiley valves) were used. Age at valve replacement ranged from 9 to 52 years (mean 23.0 years), and the follow-up period was 1.28-19.8 years (mean 5.7 years). Including 2 sudden deaths, late death occurred in 4 patients, on all of whom mechanical valve replacements were done at the primary operation. Five-year survival rate of all patients was 76.4 +/- 12.1%, and 10-year survival rate was 63.6 +/- 15.4%. All the patients who received bioprosthesis at the primary operation survived at the time of this follow-up study. On the contrary, long-term results of mechanical valve was unsatisfactory with the 5-year survival of 62.5 +/- 17.1%. In spite of anti-coagulation therapy with warfarin, three patients with mechanical valve complicated thrombotic valves, which necessitated re-operations. Calcified bioprosthetic valve occurred in one patient with I-S valve 8.5 years after the implantation. Five-year complication-free rate was 87.5 +/- 11.7% for bioprosthesis, whereas it was 50.0 +/- 15.8% for mechanical valve (p less than 0.056). It is concluded that the bioprosthesis is the first choice for the valve replacement in the right side of the heart in congenital heart disease.     

Results of reoperation for primary tissue failure of porcine bioprostheses

Results of reoperation for primary tissue failure of porcine bioprostheses were evaluated in 574 patients discharged from the hospital from 1970 to 1981. A total of 413 had undergone isolated mitral valve replacement and 161 isolated aortic valve replacement. Through March, 1984, 88 patients (15%) had required reoperation: 59 had undergone mitral and 29, aortic valve replacement. Primary tissue failure was the main cause of bioprosthetic dysfunction; it occurred in 64 patients (46 mitral and 18 aortic) at a mean postoperative interval of 93 +/- 4 months (range 34 to 158). During the same period, 11 patients required reoperation for bioprosthetic endocarditis, 11 for paravalvular leak, and two for thrombosis. These patients are not included in this review. Reoperation for primary tissue failure was performed after a mean interval of 72 +/- 6 months (range 38 to 158) for patients with aortic bioprostheses and after 101 +/- 5 months (range 34 to 153) for those with mitral bioprostheses (p less than 0.05). Overall mortality at reoperation was 12.5%: 11% for the mitral group and 16% for the aortic group. In 62 patients (45 mitral and 17 aortic) primary tissue failure was caused by calcification of the cusps, associated with severe fibrous tissue overgrowth in seven. Bioprosthetic failure was caused by an intracuspal hematoma in one patient with mitral valve replacement and by lipid infiltration of the cusps in one patient with aortic valve replacement. Actuarial freedom from bioprosthetic primary tissue failure at 12 years is 61% +/- 5% for the mitral group and 69% +/- 7% for the aortic group. On the basis of our long-term follow-up of patients after mitral or aortic replacement with a porcine bioprosthesis, we conclude: primary tissue failure is the most frequent indication for reoperation in patients with a porcine bioprosthesis; calcification of the cusp tissue is the leading cause of primary tissue failure; reoperation for primary tissue failure may be a major concern, although mortality for elective cases is low; and the limited durability of porcine bioprostheses suggests their use be restricted to selected patients.     

Porcine cardiac bioprostheses: evaluation of long-term results in 990 patients

Clinical results with porcine bioprostheses were reviewed for 990 patients who underwent heart valve replacement from January, 1974, to December, 1980. Eight hundred and seventy-four Hancock, 283 Carpentier-Edwards, and 10 Liotta bioprostheses were used. In 23 patients, 26 mechanical prostheses were implanted as well. Overall operative mortality was 60 out of 990 (6.06%): 30 out of 506 (5.9%) for mitral valve replacement (MVR), 13 out of 287 (4.5%) for aortic valve replacement (AVR), 1 out of 4 (25%) for tricuspid valve replacement, 0 out of 2 for pulmonary valve replacement, and 16 out of 191 (8.4%) for multiple valve replacement. Cumulative follow-up covered 1,793 patient-years. (Actuarial survival at 7 years was 76.6 +/- 3% for MVR. At 6 years, it was 83.2 +/- 2.8% for AVR and 55 +/- 13.5% for multiple valve replacement.) Prosthesis-related survival at 7 years was 91.7 +/- 1.9% for MVR, and at 6 years, it was 96.6 +/- 1.5% for AVR and 95.1 +/- 2.2% for multiple valve replacement. Bioprosthesis survival, considering deaths or complications that led to reoperation as final events, was 84.2 +/- 3.7% at 7 years for mitral valves and 87.7 +/- 3.8% at 6 years for aortic valves. Emboli per 100 patient-years numbered 3.2 for MVR, 0.5 for AVR, and 1.6 for multiple valve replacement. Twenty-seven patients underwent reoperation, 12 for perivalvular leak, 5 for endocarditis, 6 for valve thrombosis, and 4 for primary tissue failure (linearized rates of 0.7, 0.3, 0.3, and 0.2% per patient-year, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

The Carpentier-Edwards Supra-Annular Porcine Bioprosthesis: New Generation Low Pressure Glutaraldehyde Fixed Prosthesis

The Carpentier-Edwards supra-annular porcine bioprosthesis was implanted in 1,576 operations (1,536 patients with 1,704 valves) between 1981 and 1987. The mean age of the patients was 61.9 years (range 13 to 87 years). During the years 1981 and 1987, approximately 90% of the total valvular surgery population received the prosthesis. The early mortality was 7.0% (included patients with concomitant procedures including coronary artery bypass and ascending aortic aneurysm resection). Late mortality was 4.0% per patient-year. The total cumulative follow-up was 4,237 years. Thromboembolism (TE) was 2.4% per patient-year (fatal 0.4% per patient-year) (minor 1.2%; major 1.3%); antithromboembolic therapy-related hemorrhage (ATH) 0.5% (fatal 0.07%); prosthetic valve endocarditis (PVE) 0.5% (fatal 0.2%); periprosthetic leak (PPL) 0.3% (fatal 0%); clinical valve dysfunction (CVD) 0.3% (fatal 0.02%); and structural valve deterioration/primary tissue failure (SVD) 0.2%/patient-year (fatal 0%). Thromboembolism and structural valve deterioration were the significant complications, SVD occurring primarily between the fourth and fifth year of evaluation. The overall patient survival was 77.1% +/- 1.4% at five years. The patients were classified as 89.6% NYHA functional Class III and IV preoperatively and 96.1% Class I and II postoperatively. The freedom at five years from TE was 90.6% +/- 1.0%; SVD 98.9% +/- 0.5%; and reoperation 95.9% +/- 0.9%. Freedom from all valve-related complications at five years was 84.1% +/- 1.3%; valve-related mortality 96.8% +/- 0.7%; mortality and reoperation (valve failure) 92.9% +/- 1.1%; mortality and residual morbidity (treatment failure) 93.7% +/- 0.9%; and mortality, residual morbidity, and reoperation (valve failure and dysfunction) 90.0% +/- 1.2%. There were 28 valve-related deaths of a total 280 deaths (early 4, late 24) (TE 17; ATH 3; CVD 1; PVE 7; PPL 0; and SVD 0). Valve-related reoperations were performed in 32 patients (TE 2; CVD 4; PVE 7; PPL 11; and SVD 8). The supra-annular Carpentier-Edwards porcine bioprosthesis has provided very satisfactory clinical performance and afforded patients an excellent quality of life. The long-term durability of this low pressure glutaraldehyde fixed prosthesis will be determined by observation over the next five to seven years.     

Valve replacement in the elderly: a long term appraisal

From July 1972 through July 1983, 360 consecutive patients 70 years of age and older (mean age 74.1; range 70-88 years) underwent 362 valve replacement procedures. There were 122 isolated aortic valve replacements (33.7%; Group I); 70 isolated mitral valve replacements (19.3%; Group II); and 170 patients had combined procedures (47.0%; Group III), which included the replacement of at least one valve. Eighteen patients (5.0%) had previous cardiac surgery. Thirty-two patients (8.8%) were operated as emergencies. Three hundred and thirty-two (86.5%) of all valves implanted were porcine heterografts. Pre-operatively, over one-half (53.6%) of the patients were in New York Heart Association Functional Class IV. The overall hospital mortality was 13.8% (50 patients). The aortic valve mortality was 11.5%, the mitral valve mortality was 15.7%, and the combined procedures 14.7%. The follow-up period for hospital survivors (312 patients) extended from 2 weeks to 127.2 months, with a mean of 38.7 months or a total of 1,006 patient-years. The long term survival computed up to six years shows a 65 +/- 3.8% (standard error of the mean) for the entire group. The aortic valve group survival was 71 +/- 5.6%; the mitral valve group 60 +/- 8.2%; and the combined procedures group was 64 +/- 5.3%. Postoperative functional improvement was significant with 71.8% of the survivors in Class I and 19.6% in Class II. Based on these results, advanced age can no longer be considered a deterrant to cardiac surgery. The porcine heterograft appears to be the valve substitute of choice for this age group.(ABSTRACT TRUNCATED AT 250 WORDS)     

A five-year appraisal and hemodynamic evaluation of the Bj?rk-Shiley Monostrut valve

Two hundred forty-four Bj?rk-Shiley Monostrut valves were implanted in 225 consecutive patients from October 1983 to December 1988. Aortic valve replacement was performed in 90 patients, mitral valve replacement in 118, and double valve replacement in 16 patients. One patient had tricuspid valve replacement. There were 100 female patients and 125 male patients with a mean age of 54 years (range 2 to 71 years). Present data were completely available for all patients. The cumulative follow-up was 541 patient-years with a mean of 2 years, 5 months. The closing date for follow-up was July 1989, and the closing interval was 2 months. The early mortality rate was 3.1%, and the late mortality rate, 3.1%. The 5-year survival rate was 88% +/- 2.0%: 87% +/- 3.0% for aortic valve replacement, 91% +/- 3.3% for mitral valve replacement, and 75% +/- 9.6% for double valve replacement. The actuarial rates of freedom from thromboembolism at 5 years were 93% +/- 3.2% for aortic, 96% +/- 1.4% for mitral, and 94% +/- 6.1% for double valve replacement. There were no instances of structural valve deterioration. Actuarial rate of freedom from valve-related morbidity and mortality was 86% +/- 2.0% at 5 years: 86% +/- 9.5% for aortic, 87% +/- 3.3% for mitral, and 75% +/- 7.3% for double valve replacement. Effective valve areas (average) of 12 mitral and 12 aortic valve prostheses were calculated at rest and during bicycle exercise: 2.4 cm2 at rest and 2.8 cm2 during exercise in 27 mm aortic valves, 2.4 cm2 at rest and 3.0 cm2 during exercise in 25 mm aortic valves, 2.0 cm2 at rest and 2.4 cm2 during exercise in 27 mm mitral valves, and 2.6 cm2 at rest and 2.5 cm2 during exercise in 29 mm mitral valve. On the basis of our follow-up period of 5 years, we have judged the Bj?rk-Shiley Monostrut valve reliable, with a low incidence of valve-related morbidity and with acceptably satisfactory hemodynamic characteristics at rest and during exercise.     

Porcine versus pericardial bioprostheses: a comparison of late results in 1,593 patients

From 1976 to 1988, 1,593 patients underwent valve replacement with a porcine (878 patients) or a pericardial bioprosthesis (715 patients). There were 701 aortic, 678 mitral, and 214 multiple-valve replacements. Follow-up was obtained for 1,559 patients (98%). Early mortality was 9% (79 patients) in the porcine valve group and 5% (37 patients) among patients with a pericardial valve (p less than 0.01). Late survival after replacement with porcine valves was 80% +/- 1% and 62% +/- 3% at 5 and 10 years, respectively. With pericardial valves, 5-year survival was 79% +/- 2%. Among valve-related complications, rates of freedom from thromboembolism, endocarditis, and hemorrhage after 6 years were similar for both valve groups. Freedom from reoperation at 6 years was also similar after aortic (96% versus 91%) or multiple-valve replacement (95% versus 88%). However, for mitral valve replacement, freedom from reoperation was significantly better with porcine valves than with pericardial valves at 6 years (92% versus 68%; p less than 0.001). This difference was mainly due to the Ionescu-Shiley valve, which accounted for 83% of primary tissue failures among pericardial bioprostheses implanted in the mitral position (10/12 patients). After 6 years, freedom from primary tissue failure of mitral valves was 92% +/- 2% with porcine and 70% +/- 11% with pericardial bioprostheses (p less than 0.0001). The degree of clinical improvement among survivors was similar with both valve types. Thus, in the aortic position, pericardial valves compare with porcine valves up to 6 years, whereas in the mitral position, the durability of the former is significantly less, mainly because of the suboptimal performance of the Ionescu-Shiley pericardial bioprosthesis.     

Long-term clinical results after aortic valve replacement with mechanical heart valves and mitral valve replacement with porcine valves]

Long-term clinical results of aortic valve replacement (AVR) with mechanical heart valves and mitral valve replacement (MVR) with porcine valves were analysed. Sixty-three patients received isolated AVR and 48 received isolated MVR. Sixty-eight patients with MVR including double or triple valve replacement were also added in order to evaluate the primary tissue failure (PTF). The patients with operative deaths were excluded. Survival rate at 11 years in AVR was 68 +/- 10% and 67 +/- 15% in MVR without statistical difference. At 11 years, 76 +/- 8% of the patients in AVR were free from valve-related complications in contrast with the poor result of 34 +/- 31% in MVR (p less than 0.01). Main cause of this poor result in MVR was PTF as indicated in following event free rates; 83 +/- 9% at 7 years, 61 +/- 25% at 10 years and 49 +/- 31% at 13 years. There was no statistical difference between patients of above 50 years and below 49 years in PTF. Valve-related death event free was 93 +/- 5% in AVR and 86 +/- 11% in MVR at 11 years (not significant), however, there was statistical difference in re-operation event free rate as 94 +/- 5% in AVR and 76 +/- 11% in MVR at 11 years (p less than 0.001). These results suggest that the use of porcine valves in mitral position is confined to the selected patients.