Intermediate-term outcomes of aortic valve replacement with bioprosthetic or mechanical valves in patients on hemodialysis

ObjectiveTo investigate the influence of choice of prosthesis (bioprosthetic valves or mechanical valves) on intermediate-term outcomes in patients on hemodialysis undergoing aortic valve replacement (AVR).MethodsA multi-institutional retrospective cohort study was conducted in 18 Japanese centers. All adult patients on chronic hemodialysis who underwent AVR from 2008 and 2015 were included (n = 491). The early and late results were compared between groups. The hazard ratios were calculated using Cox regression and Fine–Gray models with adjustment for propensity score based on 41 confounders. The mean follow-up period was 2.5 ± 2.1 years (up to 8.3 years) with 98% completeness.ResultsThere were 323 patients who received a bioprosthetic valve (group B), and 168 patients who received a mechanical valve (group M). There was no significant difference for in-hospital death rate between groups (group B: 12.1%; group M: 8.9%; P = .29). The overall survival rate at 5 years after surgery was 39.3% in group B and 50.4% in group M (P = .42). Freedom from reoperation at 5 years was 97.1% in group B and 97.8% in group M (P = .88). On propensity-score adjusted analyses, there were no significant differences in overall survival between groups.ConclusionsThere were no significant differences in overall survival between bioprosthetic valves and mechanical valves in patients on hemodialysis undergoing AVR.     

Ten-year echocardiographic and clinical follow-up of aortic Carpentier-Edwards pericardial and supraannular prosthesis: a case-match study

BACKGROUND: There are little comparative data on Carpentier-Edwards supraannular and pericardial second-generation bioprostheses. The aim of this work was to compare their hemodynamic and clinical outcomes in patients with aortic stenosis. METHODS: We conducted a retrospective study including 150 patients operated on for aortic stenosis between 1989 and 1993. Patients undergoing aortic valve replacement with either a Carpentier-Edwards supraannular or pericardial prosthesis were matched for sex (49% male), age (72 +/- 8 years), body surface area, valve size, associated procedures, and left ventricular ejection fraction. RESULTS: Mean follow-up was 6.5 +/- 3.3 years, giving a total follow-up of 983 patient-years. Thirty-day mortality and 10-year actuarial survival were, respectively, 8% and 51% in the supraannular group and 6.7% and 43.4% in the pericardial group. At 10 years, freedom from thromboembolism, structural failure, and all valve-related events were, respectively, 88.7%, 88.9%, and 68.7% in the supraannular group and 85%, 100%, and 82.2% in the pericardial group. There were four (5.3%) structural failures, and four (5.3%) reoperations for degeneration (n = 3) and endocarditis (n = 1) in the supraannular group. Freedom from structural dysfunction or reoperation was 87.3% in the supraannular group and 100% (p < 0.05) in the pericardial group. Echocardiographic review of 62 of 76 survivors (81.5%) demonstrated a trend toward a better hemodynamic profile of pericardial valves at the end of follow-up. CONCLUSIONS: Ten years after aortic valve replacement for aortic stenosis, Carpentier-Edwards pericardial prostheses give comparable and probably better results than Carpentier-Edwards supraannular prostheses.     

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 outcome after biologic versus mechanical aortic valve replacement in 841 patients

OBJECTIVE: The purpose of this study was to optimize selection criteria of biologic versus mechanical valve prostheses for aortic valve replacement. METHODS: Retrospective analysis was performed for 841 patients undergoing isolated, first-time aortic valve replacement with Carpentier-Edwards (n = 429) or St Jude Medical (n = 412) prostheses. RESULTS: Patients with Carpentier-Edwards and St Jude Medical valves had similar characteristics. Ten-year survival was similar in each group (Carpentier-Edwards 54% 3% versus St Jude Medical 50% 6%; P =.4). Independent predictors of worse survival were older age, renal or lung disease, ejection fraction less than 40%, diabetes, and coronary disease. Carpentier-Edwards versus St Jude Medical prostheses did not affect survival (P =.4). Independent predictors of aortic valve reoperation were younger age and Carpentier-Edwards prosthesis. The linearized rates of thromboembolism were similar, but the linearized rate of hemorrhage was lower with Carpentier-Edwards prostheses (P <.01). Perivalvular leak within 6 months of operation was more likely with St Jude Medical than with Carpentier-Edwards prostheses (P =.02). Estimated 10-year survival free from valve-related morbidity was better for the St Jude Medical valve in patients aged less than 65 years and was better for the Carpentier-Edwards valve in patients aged more than 65 years. Patients with renal disease, lung disease (in patients more than age 60 years), ejection fraction less than 40%, or coronary disease had a life expectancy of less than 10 years. CONCLUSIONS: For first-time, isolated aortic valve replacement, mechanical prostheses should be considered in patients under age 65 years with a life expectancy of at least 10 years. Bioprostheses should be considered in patients over age 65 years or with lung disease (in patients over age 60 years), renal disease, coronary disease, ejection fraction less than 40%, or a life expectancy less than 10 years.     

Mechanical versus bioprosthetic valve replacement in middle-aged patients.

OBJECTIVE: The current trend towards decreasing the age for selection of a tissue over a mechanical prosthesis has led to a dilemma for patients aged 50-65 years. This cohort study examines the long-term outcomes of mechanical versus bioprosthetic valves in middle-aged patients. METHODS: Patients (N = 659) aged between 50 and 65 years who had first-time aortic valve replacement (AVR) and/or mitral valve replacement (MVR) with contemporary prostheses were followed prospectively after surgery. The total follow-up was 3,402 patient-years (mean 5.1 +/- 4.1 years; maximum 18.3 years). Outcomes were examined with multivariate actuarial methods. A composite outcome of major adverse prosthesis-related events (MAPE) was defined as the occurrence of reoperation, endocarditis, major bleeding, or thromboembolism. RESULTS: Ten-year survival was 73.2 +/- 4.2% after mechanical AVR, 75.1 +/- 12.6% after bioprosthetic AVR, 74.1 +/- 4.6% after mechanical MVR, and 77.9 +/- 7.4% after bioprosthetic MVR (P=NS). Ten-year reoperation rates were 35.4% and 21.3% with aortic and mitral bioprostheses, respectively. Major bleeding occurred more often following mechanical MVR (hazard ratio [HR]: 3.3; 95% confidence interval [CI] 1.2, 9.0; P = 0.022), and the incidence of any thromboembolic event was more common after mechanical MVR (HR: 4.7; CI 1.4, 13.3; P = 0.01). Overall freedom from MAPE at 10 years was 70.2 +/- 4.1% for mechanical AVR patients, 41.0+/-30.3% for bioprosthetic AVR patients, 53.3 +/- 8.8% for mechanical MVR patients, and 61.2 +/- 9.2% for bioprosthetic MVR patients. Although a trend existed towards more MAPE amongst middle-age patients with tissue valves, multivariate analysis did not identify the presence of a bioprosthesis as an independent risk factor for MAPE (HR: 1.3; CI 0.9, 2.0; P = 0.22). CONCLUSIONS: In middle-aged patients, MAPE may occur more often in patients with bioprosthetic valves, but definitive conclusions necessitate the accumulation of additional follow-up. At present, these data do not support lowering the usual cutoff for implantation of a tissue valve below the age of 65.     

Comparison of Carpentier-Edwards pericardial and supraannular bioprostheses in aortic valve replacement.

OBJECTIVE: This study aimed at calculating and comparing the long-term outcomes of patients after aortic valve replacement with the Carpentier-Edwards bovine pericardial and porcine supraannular bioprostheses using microsimulation. METHODS: We conducted a meta-analysis of eight studies on the Carpentier-Edwards pericardial valves (2,685 patients, 12,250 patient-years) and five studies on the supraannular valves (3,796 patients, 20,127 patient-years) to estimate the occurrence rates of valve-related events. Eighteen-year follow-up data sets were used to construct age-dependent Weibull curves that described their structural valvular deterioration. The estimates were entered into a microsimulation model, which was used to calculate the outcomes of patients after aortic valve replacement. RESULTS: The annual hazard rates for thrombo-embolism after aortic valve replacement were 1.35% and 1.76% for the pericardial and supraannular valves, respectively. For a 65-year-old male, median time to structural valvular deterioration was 20.1 and 22.2 years while the lifetime risk of reoperation due to structural valvular deterioration was 18.3% and 14.0%, respectively. The life expectancy of the patient was 10.8 and 10.9 years and event-free life expectancy 9.0 and 8.8 years, respectively. CONCLUSIONS: The microsimulation methodology provides insight into the prognosis of a patient after aortic valve replacement with any given valve type. Both the Carpentier-Edwards pericardial and supraannular valve types perform satisfactorily, especially in elderly patients, and show no appreciable difference in long-term outcomes when implanted in the aortic position.     

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)     

Outcomes after mechanical aortic valve replacement in children and young adults with congenital heart disease

Objectives

There are little recent data on the outcomes of mechanical aortic valve replacement (AVR) in children and young adults with congenital aortic valve disease. We sought to review the survival and associated thromboembolic or bleeding complications after mechanical AVR at a single center.

Elderly valve replacement with bioprostheses and mechanical prostheses. Comparison by composites of complications

AIM: The goal of aortic valve replacement (AVR) surgery in the elderly (= or >75 years) is to extend survival and minimize valve-related morbidity, mortality and reoperation. As the elderly population lives longer, those with implanted valves are at risk of suffering valve related complications. We hypothesize that bioprostheses are appropriate for the elderly. METHODS: The follow-up evaluation of 966 patients with valves (AVR, 666; mitral valve replacements [MVR], 226; multiple valve replacements [MR], 74) implanted between 1975 and 1999 was examined. There were 879 bioprotheses (BP) and 87 mechanical prostheses (MP). The mean age was 78.9+/-3.3 years (range 75-94.6 years). Concomitant coronary artery bypass was performed in AVR in 51.7%, MVR in 50.4% and MR in 28.4%. Valve type, valve lesion, coronary artery bypass (previous/concomitant), age and gender were considered as independent predictors of composites and survival. The total follow-up was 3905 patient-years. RESULTS: Early mortality was for AVR 9.6% (64), MVR 15.0% (34) and MR 25.7% (19). The late mortality was for AVR 8.8%, MVR 10.4% and MR 8.8%/patient-year. The only independent predictor of survival and valve-related mortality, morbidity and reoperation was age for survival in those with AVR, hazard ratio 1.15 [CL 1.03-1.27] p=0.0094). The BP reoperative rate was 0.5%/patient-year (reoperation was fatal in 6/15) of total, MP reoperative rate was 0% [reasons for reoperation structural valve deterioration (4), non-structural dysfunction (6), prosthetic valve endocarditis (5), reoperation fatality due to non-structural dysfunction (2), prosthetic valve endocarditis (4)]. Overall patient survival at 10 and 15 years, respectively, was 30.5+/-2.4% and 3.6+/-2.2% irrespective of valve position and type. Overall actual and actuarial freedom from valve-related morbidity at 15 years was 96.8+/-0.9% and 93.7+/-2.3%, respectively. Actual and actuarial overall freedom from valve-related mortality at 15 years was 84.3+/-2.4% and 58.4+/-0.9%, respectively. Overall actual and actuarial freedom from valve related reoperation at 15 years was 95.8+/-1.6% and 74.8+/-16.9%, respectively. CONCLUSIONS: BP valves are further confirmed to be a good option for AVR in patients = or >75 years of age.     

Late incidence and determinants of reoperation in patients with prosthetic heart valves.

OBJECTIVES: Reoperation is a relatively common event in patients with prosthetic heart valves, but its actual occurrence can vary widely from one patient to another. With a focus on bioprosthetic valves, this study examines risk factors for reoperation in a large patient cohort. METHODS: Patients (N=3233) who underwent a total of 3633 operations for aortic (AVR) or mitral valve replacement (MVR) between 1970 and 2002 were prospectively followed (total 21,179 patient-years; mean 6.6+/-5.0 years; maximum 32.4 years). The incidence of prosthetic valve reoperation and the impact of patient- and valve-related variables were determined with actual and actuarial methods. RESULTS: Fifteen-year actual freedom from all-cause reoperation was 94.1% for aortic mechanical valves, 61.4% for aortic bioprosthetic valves, 94.8% for mitral mechanical valves, and 63.3% for mitral bioprosthetic valves. In both aortic and mitral positions, current bioprosthesis models had significantly better durability than discontinued bioprostheses (15-year reoperation odds-ratio 0.11+/-0.04; P<0.01 for aortic, and 0.42+/-0.14; P=0.009 for mitral). Current bioprostheses were significantly more durable in the aortic position than in the mitral position (14.3+/-6.8% more freedom from 15-year reoperation; (P=0.018)). Older age was protective, but smoking was an independent risk factor for reoperation after bioprosthetic AVR and MVR (hazard ratio for smoking 2.58 and 1.78, respectively). In patients with aortic bioprostheses, persistent left ventricular hypertrophy at follow-up and smaller prosthesis size predicted an increased incidence of reoperation, while this was not observed in patients with mitral bioprostheses. CONCLUSIONS: These analyses indicate that current bioprostheses have significantly better durability than discontinued bioprostheses, reveal a detrimental impact for smoking after AVR and MVR, and indicate an increased reoperation risk in patients with a small aortic bioprosthesis or with persistent left ventricular hypertrophy after AVR.     

Comparison of survival after mitral valve replacement with biologic and mechanical valves in 1139 patients

OBJECTIVE: We sought to compare 10-year survival in patients after mitral valve replacement with biologic or mechanical valve prostheses. METHODS: Retrospective survival analysis was performed on data from 1139 consecutive patients older than 18 years of age undergoing mitral valve replacement with Carpentier-Edwards (n = 495; Baxter Healthcare Corp, Irvine, Calif) or St Jude Medical (n = 644; St Jude Medical, Inc, St Paul, Minn) prostheses. RESULTS: The 10-year survival was not statistically different between the patients receiving Carpentier-Edwards valves and those receiving St Jude Medical valves (P =.16). Adjusted survival estimates at 2, 5, and 10 years were 82% +/- 2% (95% confidence intervals, 79%-85%), 69% +/- 2% (95% confidence intervals, 64%-73%), and 42% +/- 3% (95% confidence intervals, 37%-48%), respectively, for the Carpentier-Edwards group and 83% +/- 2% (95% confidence intervals, 80%-86%), 72% +/- 2% (95% confidence intervals, 69%-76%), and 51% +/- 3% (95% confidence intervals, 45%-58%), respectively, for the St Jude Medical group. Predictors of worse survival after mitral valve replacement are older age, lower ejection fraction, presence of class IV congestive heart failure, coronary artery disease, renal disease, smoking history, hypertension, concurrent other valve surgery, and redo heart surgery. CONCLUSION: Choice of biologic or mechanical prosthesis does not significantly affect long-term patient survival after mitral 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.     

Performance of bioprostheses and mechanical prostheses assessed by composites of valve-related complications to 15 years after mitral valve replacement

OBJECTIVE: Predominant concerns of patients undergoing valve replacement surgery are risks of death, stroke, antithrombotic bleeding, and reoperation related to the replacement prosthesis. The purpose of this study was to compare valve-related reoperation, morbidity (permanent impairment), and mortality between bioprostheses and mechanical prostheses for mitral valve replacement. METHODS: Between 1982 and 1998, a total of 959 bioprostheses were implanted in 943 patients, and a total of 961 mechanical prostheses were implanted in 839 patients. Total follow-ups were 5730 years for bioprostheses and 5271 years for mechanical prostheses. Eight variables were considered as predictors of risk for the composites of valve-related complications. RESULTS: The linearized occurrence rates for valve-related reoperation were 3.7 events/100 patient-years for bioprostheses and 0.5 events/100 patient-years for mechanical prostheses ( P < .001), with all age groups differentiated except older than 70 years. Valve-related morbidity was undifferentiated for bioprostheses and mechanical prostheses. Valve-related mortalities were 1.7 events/100 patient-years for bioprostheses and 0.7 events/100 patient-years for mechanical prostheses ( P < .001). Predictors of valve-related reoperation were age and valve type. The only predictor of valve-related morbidity was age, whereas age and valve type were predictors for valve-related mortality. Actual freedom from valve-related reoperation favored mechanical prostheses in all age groups except older than 70 years (91.7% +/- 2.0% for bioprostheses at 15 years and 96.7% +/- 1.5% at 12 years for mechanical prostheses). Actual freedom from valve-related morbidity was not different between bioprostheses and mechanical prostheses. Actual freedom from valve-related mortality favored mechanical prostheses in all groups except older than 70 years. CONCLUSION: Comparative evaluation gives high priority in mitral valve replacement for mechanical prostheses relative to bioprostheses for freedom from valve-related reoperation and valve-related mortality but not valve-related morbidity. Freedom from valve-related reoperation and valve-related mortality favors mechanical prostheses for all age groups except older than 70 years. Valve-related morbidity, due to neurologic or functional impairments, does not differentiate between bioprostheses and mechanical prostheses.     

The risks of reoperation for prosthetic valve dysfunction

A retrospective study was conducted on 124 patients who underwent re-replacement of previously implanted prosthetic heart valves for structural valve failure, prosthetic valve endocarditis, periprosthetic leak, a thrombosed valve, hemolysis, or prophylactic removal. In total, 85% of the explanted valves were bioprostheses, and 70% of the newly implanted valves were mechanical valves. The overall operative mortality rate was 8.1%, being 3.2% of 95 single valve recipients and 25.0% of 28 double valve recipients (P < 0.001). The overall mortality rate dropped from 13.6% of 66 patients before 1988, to 1.7 % of 58 patients encountered in the last 3 years (P < 0.02). Since 1988, a third of the patients have undergone reoperation without homologous blood transfusion. A univariate analysis revealed eight operative risk factors, namely: higher values of preoperative blood urea nitrogen or total bilirubin, double valve replacement at the redo operation, NYHA class IV, urgency of reoperation, a duration of implantation of less than 3 months, reoperation in the earlier period of this study, and reexploration for bleeding or cardiac tamponade after re-replacement surgery. A multivariate statistcial analysis demonstrated that preoperative blood urea nitrogen, urgency of reoperation, double valve replacement, and the duration of implantation were independent risk factors. Thus, we recommend that surgery be performed early, before the occurrence of other organ failure induced by congestive heart failure due to any form of valve dysfunction.     

Choice of a mechanical valve or a bioprosthesis for AVR: does CABG matter?

OBJECTIVE: Mechanical valves and bioprostheses are the commonly used devices in aortic valve replacement (AVR). Many patients with valvular disease also require concomitant coronary artery bypass grafting (CABG). We used a microsimulation model to provide insight into the outcomes of patients after AVR with mechanical valves and stented bioprostheses, with and without CABG, and to determine the age-thresholds or age crossover points in outcomes between the two valve types. METHODS: We conducted a meta-analysis of published results after primary AVR with mechanical prostheses (nine reports, 4274 patients, 25,726 patient-years) and stented porcine bioprostheses (13 reports, 9007 patients, 54,151 patient-years) to estimate risks of valve-related events. A hazard ratio of 1.3 was used to incorporate the effect of CABG on long-term survival. Estimates were entered into a microsimulation model, which was then used to predict the outcomes of patients after AVR, with and without CABG. The model calculations were validated using a large data set from Portland, USA. RESULTS: For a 65-year-old male without CABG, the life expectancy (LE) was 11.2 and 11.6 years and the event-free life expectancy (EFLE) was 8.2 and 8.9 years, respectively, after implantation with mechanical valves and bioprostheses. The lifetime risk of at least one valve-related event was 51 and 47%, respectively. The age crossover point between the two valve types, considering the above outcome parameters, was 59, 60 and 63 years, respectively. CABG reduced LE and consequently EFLE and lifetime risk of an event, but only minimally influenced the patient age crossover points. The model calculations showed good agreement with the Portland data. CONCLUSIONS: The currently recommended patient age for using a bioprosthesis (65 years) could be lowered further, irrespective of concomitant CABG. The trade-off between the reduced risks of bioprosthetic failure and of hemorrhage in mechanical valves, resulting from a lower LE, minimized the effect of CABG on the age crossover points between the two valve types.     

The behavior of pericardial versus porcine valve xenografts in the growing sheep model

The comparative long-term behavior of the pericardial versus the porcine bioprostheses is not yet known. The need for long follow-up times to answer this question makes the growing sheep model an attractive alternative, given its ability to induce early valve degeneration. Sixty-three sheep, 12 to 16 weeks old, were operated on and received 39 porcine (11 Xenomedica, 10 Carpentier-Edwards S, nine Hancock I standard, and nine Hancock I T6-treated) and 24 pericardial (14 Mitroflow and 10 Ionescu-Shiley low profile) prostheses of clinical quality in the tricuspid position. Of the 52 operative survivors (32 received porcine valves and 20 received pericardial bioprostheses), six animals (five pericardial and one porcine) were eliminated because of bioprosthetic infection. Late sudden death before the scheduled killing occurred significantly more often (p less than 0.0001) in the pericardial (8/15 or 53%) than in the porcine group (1/31 or 3%). Calcium content of the explanted valves was significantly correlated with time in the pericardial group and the Xenomedica porcine prostheses (p less than 0.05) but not in the Hancock I and Carpentier-Edwards S valves, where it was only marginally significant (0.1 greater than p greater than 0.05). Linear regression analysis of tissue calcium content showed a similar slope for the pericardial group and Xenomedica porcine valves, in comparison with the remaining porcine valves. Comparison between the two lines using covariance analysis demonstrated a statistically significant difference between them, which shows that the pericardial and Xenomedica porcine valves appear to reach higher levels of calcification in a shorter follow-up time than the Hancock I, standard and T6-treated, and the Carpentier-Edwards S valve in this animal model.     

The fate of small-size pericardial heart valve prostheses in an older patient population

Background

Structural valve deterioration (SVD) is the Achilles' heel of bioprostheses. Its correlation with younger age is well known. In recent years we exclusively reserved use of small-size Mitroflow valve prostheses (LivaNova, London, United Kingdom) to an older patient population with small aortic annuli. This study aimed to assess the incidence of SVD and its effect on patient survival and need for reoperation.

Cardiac valve replacement in patients on dialysis: influence of prosthesis on survival

BACKGROUND: Mechanical valves have been recommended for patients on dialysis because of purported accelerated bioprosthesis degeneration. This study was undertaken to determine time-related outcomes in dialysis patients requiring cardiac valve replacement. METHODS: From 1986 to 1998, 42 patients on chronic preoperative dialysis underwent valve replacement; 17 received mechanical valves and 25 received bioprostheses. Age was similar in both groups: 54+/-18.5 years (mechanical) and 59+/-15.5 years (bioprosthetic, p = 0.4). Sites of valve replacement were aortic (27), mitral (11), and aortic and mitral (4). Follow-up was 100% complete. RESULTS: Survival at 3 and 5 years was 50% and 33% after mechanical valve replacement, and 36% and 27% after bioprosthetic valve replacement (p = 0.3). Four patients with bioprostheses required reoperation: 3 for allograft endocarditis and 1 at 10 months for mitral bioprosthesis degeneration. One patient who received a mechanical valve required reoperation. CONCLUSIONS: Prosthetic valve-related complications in patients on dialysis were similar for both mechanical and bioprosthetic valves. Because of the limited life expectancy of patients on dialysis, bioprosthesis degeneration will be uncommon. Therefore, surgeons should not hesitate to implant bioprosthetic valves in these patients.     

Determinants of survival and valve failure after mitral valve replacement

A prospective evaluation of 333 consecutive patients undergoing isolated mitral valve replacement between 1982 and 1985 was performed to identify the predictors of survival and valve failure. Follow-up between 2 and 6 years postoperatively (mean, 32 +/- 17 months) was 98% complete. Four prostheses were inserted to permit a prospective evaluation of alternative valves: Bj?rk-Shiley mechanical (n = 118), Ionescu-Shiley pericardial (n = 146), Carpentier-Edwards porcine (n = 38), and Hancock pericardial (n = 31). Hospital mortality was 6%, and actuarial survival at 5 years was 74% +/- 5%. Multivariate Cox regression analysis identified advancing age (less than 40 years, 88% +/- 7%; greater than 70 years, 50% +/- 14%) and poor left ventricular function (ejection fraction less than 0.20, 62% +/- 17%; ejection fraction greater than 0.60, 80% +/- 7%) as independent predictors of postoperative survival. Freedom from structural valve dysfunction, prosthetic valve endocarditis, reoperation, and valve-related mortality and morbidity were 86% +/- 4%, 91% +/- 4%, 81% +/- 4%, and 72% +/- 5%, respectively, at 5 years. The actuarial incidence of valve failure was inordinately high with the Hancock pericardial valve (p less than 0.05). Freedom from thromboembolic events (78% +/- 8% at 5 years) was significantly lower in patients with poor ventricular function (ejection fraction (less than 0.20, 54% +/- 20%; ejection fraction greater than 0.60, 73% +/- 11%; p less than 0.05). Survival after mitral valve replacement was determined by age and left ventricular function. Premature failure of the Hancock pericardial valve resulted in an unacceptable rate of valve-related complications.     

Bioprosthetic aortic valve replacement in elderly patients: Meta-analysis and microsimulation

ObjectiveTo support decision-making in aortic valve replacement (AVR) in elderly patients, we provide a comprehensive overview of outcome after AVR with bioprostheses.MethodsA systematic review was conducted of studies reporting clinical outcome after AVR with bioprostheses in elderly patients (mean age ≥70 years; minimum age ≥65 years) published between January 1, 2000, to September 1, 2016. Reported event rates and time-to-event data were pooled and entered into a microsimulation model to calculate life expectancy and lifetime event risks.ResultsForty-two studies reporting on 34 patient cohorts were included, encompassing a total of 12,842 patients with 55,437 patient-years of follow-up (pooled mean follow-up 5.0 ± 3.3 years). Pooled mean age was 76.5 ± 5.5 years. Pooled early mortality risk was 5.42% (95% confidence interval [CI], 4.49-6.55), thromboembolism rate was 1.83%/year (95% CI, 1.28-3.61), and bleeding rate was 0.75%/year (95% CI, 0.50-1.11). Structural valve deterioration (SVD) was based on pooled time to SVD data (Gompertz; shape: 0.124, rate: 0.003). For a 75-year-old patient, this translated to an estimated life expectancy of 9.8 years (general population: 10.2 years) and lifetime risks of bleeding of 7%, thromboembolism of 17%, and reintervention of 9%.ConclusionsThe low risks of SVD and reintervention support the use of bioprostheses in elderly patients in need of AVR. The estimated life expectancy after AVR was comparable with the general population. The results of this study inform patients and clinicians about the expected outcomes after bioprosthetic AVR and thereby support treatment decision-making. Furthermore, our results can be used as a benchmark for long-term outcomes after transcatheter aortic valve implantation in patients who were eligible for surgery and other (future) alternative treatments (eg, tissue-engineered heart valves).