A 10-year comparison of mitral valve replacement with Carpentier-Edwards and Hancock porcine bioprostheses

Two hundred fifty-three patients who underwent isolated mitral valve replacement with a porcine bioprosthesis had long-term evaluation. One hundred forty-seven patients received a Carpentier-Edwards porcine bioprosthesis and 106, a Hancock valve. There were no significant differences in preoperative clinical characteristics between the two groups. Cumulative follow-up was 1,375 patient-years. At 10 years, 93% +/- 2.5% of the patients in the Carpentier-Edwards group and 85% +/- 7.8% of those in the Hancock group were free from valve-related death (not significant), and 95% +/- 2% and 91% +/- 3.8%, respectively, were free from thromboembolism (not significant). At 10 years, 65% +/- 7.2% of the patients in the Carpentier-Edwards group and 66% +/- 7.2% of those in the Hancock group were free from structural valve deterioration (not significant), and 64% +/- 6% and 59% +/- 7.3%, respectively, were free from reoperation (not significant). We conclude that the first generation of Carpentier-Edwards and Hancock prostheses produce comparable long-term results in the mitral position.     

Comparison of porcine valve xenografts with mechanical prostheses. A 7 1/2 year experience

A total of 479 valve replacements were performed in 469 patients for aortic, mitral, and tricuspid disease. A total of 529 valves were implanted (311 Carpentier-Edwards, 118 Hancock, 94 Bj?rk-Shiley, and six other mechanical valves). Of the 479 operations, 51.1% (245) were carried out in male patients and 48.9% (234) were carried out in female patients. The mean age was 57.6 years; however, 28.6% (137) of the operations were performed in patients over 65 years of age. One hundred five patients (21.9%) had had previous cardiac operations of one type or another. Follow-up was 99.6% and the average length of follow-up was 36.2 months. The overall operative mortality was 5.6%. The operative mortality in the isolated aortic valve replacement group was 2.0% and that in the mitral valve replacement group, 4.4%. There was a 5.9% valve explant rate in the Hancock series; however, no valve explants were required because of valve dysfunction in either the Carpentier-Edwards or the Bj?rk-Shiley groups. The thromboembolic rate in the aortic valve position was 2.4, 1.1, and 2.1 emboli per 100 patient-years in the Hancock, Carpentier-Edwards, and Bj?rk-Shiley groups, respectively. The thromboembolic rate in the mitral valve position was 2.8, 2.2, and 1.0 emboli per 100 patient-years in the Hancock, Carpentier-Edwards, and Bj?rk-Shiley groups, respectively.     

Excellent durability of the Hancock porcine bioprosthesis in the tricuspid position. A sixteen-year follow-up study.

From February 1975 to August 1981, 23 consecutive patients underwent tricuspid valve replacement, which was either isolated (six patients) or combined with the replacement of other valves (17) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprostheses. Patients' ages ranged from 9 to 53 (mean 36.2) years. The follow-up period ranged from 0.2 to 16.5 years (mean 9.1) and was complete in 100% of all cases. Structural valve failure of the tricuspid Hancock valve was noticed in two patients, a 9-year-old boy and a 13-year-old girl 3.4 and 16.5 years after implantation, respectively. The actuarial freedom rate from structural valve failure at 10 years was 94 +/- 6%. There were six tricuspid prosthesis-related events: structural valve failure in two and valve thrombosis, anticoagulant-related bleeding, prosthetic valve endocarditis, and periprosthetic leak in one each, respectively. The actuarial freedom from these events at 10 years was 78 +/- 10%. Five pairs of aortic/mitral-tricuspid Hancock valves were explanted simultaneously from the same patients after 8.1 to 13.9 (mean 11.4) years postoperatively. A gross examination showed no valve dysfunction in the explants from the tricuspid position, but degenerative changes with valve dysfunction in those from the mitral and aortic position were observed (none of five versus five of seven; p < 0.03). We concluded that the selection of a Hancock bioprosthesis in the tricuspid position is acceptable because of the low incidence of prosthesis-related complications and the excellent durability of more than 10 years.     

Early mechanical failures of the Hancock pericardial xenograft

From August 1981 to July 1984, a total of 97 Hancock pericardial xenografts were implanted in 84 patients, whose ages ranged from 13 to 75 years (mean 55.7 +/- 13). Mitral value replacement was performed in 17, aortic valve replacement in 54, and mitral-aortic valve replacement in 13. Operative survivors were reevaluated from July to September 1985. Cumulative duration of follow-up is 167 patient-years (range 0.5 to 4.1 years), and follow-up is 99% complete. The overall late mortality (at 4 years) is 3.6% +/- 1.4% per patient year, and the actuarial survival rate is 95.4% +/- 3% for aortic valve replacement, 74.7% +/- 16.5% for mitral valve replacement, and 67.1% +/- 20.7% for mitral-aortic valve replacement. One patient sustained a thromboembolic event after mitral valve replacement, but no such complications occurred after aortic or mitral-aortic valve replacement. Actuarial freedom from embolism at 4 years is 100% for aortic and mitral-aortic valve replacement and 93.3% +/- 6.4% for mitral valve replacement. Reoperation for Hancock pericardial xenograft dysfunction was performed in seven patients (five aortic and two mitral-aortic). In the aortic valve replacement group the causes were endocarditis in one, paravalvular leak in one, and primary tissue failure in three; all survived reoperation. The two patients with mitral-aortic valve replacement required reoperation because of primary tissue failure of both Hancock pericardial xenografts, and one died. All values explanted because of primary tissue failure showed commissural tears causing severe prosthetic regurgitation. Calcium deposits were severe in one and mild but unrelated to the cusp rupture in another. Collagen disarray was seen only at the site of the tears, whereas the collagen structure was well preserved in the intact parts of the cusps. Four patients with aortic valve replacement and one with mitral valve replacement show evidence of Hancock pericardial xenograft failure and are awaiting reoperation. The actuarial freedom from primary tissue failure at 4 years is 74.3% +/- 9.8% for aortic and 78.9% +/- 13.2% for mitral Hancock pericardial xenografts. At medium-term follow-up, the Hancock pericardial xenograft has shown poor durability and an extremely high rate of early mechanical failure, especially in the aortic position. These observations suggest the need for a close follow-up of Hancock pericardial xenograft recipients and possibly elective reoperation in asymptomatic patients with clinical evidence of prosthetic failure. These results have led us to discontinue the clinical use of this pericardial xenograft.     

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.     

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.     

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.     

Necessity of permanent anticoagulant therapy for isolated mitral valve replacement with bioprosthetic heart valve to prevent the postoperative thromboembolic complications

One hundred fifty four patients underwent isolated mitral valve replacement with bioprosthetic heart valve at Hyogo Medical College Hospital from November 1973 to December 1998. A porcine bioprosthetic valve was replaced in 82 patients (Hancock 43, Carpentier-Edwards 26, Hancock II 13) and pericardial bioprosthetic valve in 72 patients (Ionescue-Shiley 39, Carpentier-Edwards 33) with a mean follow-up of 1,410 patients-years. Their thromboembolism rates were also analyzed in linear and actuarial term over the 15-year period. The incidence of thromboembolism rate was 2.5%/pt.yr. Thromboembolic free rates for patients with anticoagulant therapy were significantly decreased for patients without therapy. Thromboembolic free rates for patients with atrial fibliration were also were significantly decreased for patients with sinus rhythm because the patients with sinus rhythm were not on anticoagulant therapy. In conclusion, it is necessary for the all patients to be on anticoagulant therapy after mitral valve replacement with bioprosthetic valves, even though patients with sinus rhythm.     

Failure of Hancock xenograft valve: importance of valve position (4- to 9-year follow-up)

To evaluate long-term durability of Hancock valves, we reviewed our results in 107 hospital survivors (120 valves) who were operated on during 1974 through mid-1979. Mitral valve replacement was done in 63 patients, aortic valve replacement in 20, and mitral valve replacement combined with other procedures in 24. The 7-year survival was 84 +/- 4% (standard error of the mean) for 91 patients and 97 valves. During a follow-up of 590 patient-years, 15 (12 mitral and 3 aortic) of 120 valves at risk (87 mitral, 32 aortic, 1 tricuspid) were removed from 14 patients. Six valves (3 mitral and 3 aortic) were removed because of bacterial endocarditis. One mitral valve was removed because of thromboembolism. Eight mitral valves were removed because of valve structural failure, which occurred at a mean follow-up of 42 months. These valves showed extensive calcification, leaflet perforation, or cusp tear. Structural failure was unrelated to valve size, year of implantation, or valve shelf-life. Structural failure was not seen after aortic valve replacement. Results show that structural failure of the Hancock xenograft valve in the mitral position is related primarily to valve position. After aortic valve replacement, valve failure is predominantly due to endocarditis. Although medium-term (mean, 6-year) durability of this xenograft valve compares satisfactorily with prosthetic valves, its high failure rate in the mitral position indicates the necessity for improvement in valve mounting, design, and preservation.     

Long-term performance of the Hancock porcine bioprosthesis in the tricuspid position. A review of forty-five patients with fourteen-year follow-up

Because little information is available regarding the clinical performance of the Hancock porcine bioprosthesis (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) implanted in the tricuspid position, we reviewed the long-term follow-up of patients who had tricuspid valve replacement with this device. From March 1970 to December 1983, 45 patients had tricuspid valve replacement, either isolated (seven patients) or combined with replacement of other valves (38 patients) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprosthesis. Follow-up ranged from 0.2 to 14.7 years (mean, 7.6 +/- 3.6 years) and was complete. The late mortality rate was 6.6% +/- 1.6%/pt-yr and the actuarial survival rate at 14 years was 23% +/- 9%. Reoperation because of structural deterioration of the tricuspid, the mitral, or both bioprostheses was performed in nine patients (3.7% +/- 1.2%/pt-yr) from 40 to 177 months (mean, 112 +/- 43 months) and resulted in no deaths. Actuarial freedom from structural deterioration of a Hancock tricuspid porcine bioprosthesis at 14 years is 68% +/- 13%. Morphologic examination of explanted porcine bioprostheses showed that those implanted in the tricuspid position had lower degrees of calcification and less severe structural changes than those simultaneously explanted from the mitral position. We conclude that the Hancock porcine bioprosthesis has an acceptable long-term durability and satisfactory performance after tricuspid valve replacement, and we continue to favor its use in the tricuspid position even in association with mechanical prostheses in the left side of the heart.     

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.     

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.     

Late results of heart valve replacement with the Hancock II bioprosthesis

OBJECTIVE: To review the late clinical outcomes of patients who had isolated aortic or mitral valve replacement with the Hancock II bioprosthesis. METHODS: From 1982 to 1994, 670 patients underwent isolated aortic valve replacement and 310 underwent isolated mitral valve replacement with the Hancock II bioprosthesis (Medtronic Inc, Minneapolis, Minn). Mean age was 65 +/- 12 years in both groups. Most patients were in New York Heart Association functional classes III or IV, and concomitant coronary artery disease was present in 44% of patients in the aortic valve group and 41% of patients in the mitral valve group. Patients were followed up prospectively at periodic intervals. Mean follow-up was 87 +/- 45 months in the aortic valve group and 83 +/- 50 months in the mitral valve group, and it was 99% complete. RESULTS: Actuarial survival at 15 years was 47% +/- 3% in the aortic valve group and 30% +/- 5% in the mitral valve group. Older age, advanced functional class, impaired left ventricular function, active endocarditis, and coronary artery disease were independent predictors of late death. The freedom from thromboembolic complications at 15 years was 83% +/- 3% in the aortic and 87% +/- 3% in the mitral valve group. The freedom from infective endocarditis at 15 years was 96% +/- 1% in the aortic and 91% +/- 1% in the mitral valve group. At 15 years, the actuarial and actual freedom from structural valve deterioration was 81% +/- 5% and 90% +/- 3%, respectively, in the aortic group and 66% +/- 6% and 83% +/- 3%, respectively, in the mitral group. Younger age, mitral valve position, and poor ventricular function were independent predictors of structural valve deterioration. The freedom from repeat valve replacement at 15 years was 77% +/- 5% in the aortic group and 69% +/- 6% in the mitral. The vast majority of patients had functional improvement after valve replacement. CONCLUSIONS: The Hancock II bioprosthesis has provided good clinical outcomes and is a durable valve, particularly in the aortic position in older patients.     

Primary failure of pericardial valvular heterografts

From July 1981 to October 1984, 79 Hancock pericardial valves were implanted in 74 patients surviving the hospital period and with a mean age of 64.2 years. Fifty-two patients underwent aortic valve replacement, 16 had mitral valve replacement, 5 bad a double replacement and 19 associated procedures were performed. The mean survival is 48 months. Until 1st June 1987, 11 primary failures have required reoperation (14.9%), 4 in the mitral position (4.6% patient-years), 7 in the aortic position (3.01% patient-years). The time to reoperation was 48.4 months for the aortic orifice and 36.5 months for the mitral orifice. The lesions most frequently encountered were tears (7 cases), calcifications (5 cases) and stretching of valvular tissue (2 cases); two patients died during the postoperative phase of this operation. Despite the small number of patients followed, this series demonstrates of high incidence of dysfunction due to primary tissue degeneration as, after the 5th year, the actuarial rate of absence of primary lesion is 85.3 +/- 8% with no significant difference between the aortic and the mitral orifices, although dysfunction appears to occur more rapidly in mitral prostheses. These results are much less favourable than those obtained with Ionescu bioprostheses in the aortic position of those obtained with porcine bioprostheses in either position. This justifies very regular clinical and echocardiographic follow-up of patients with Hancock pericardial valvular heterografts.     

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.     

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)     

Cardiac valve replacement in the elderly]

From January 1980 through December 1990, seventy one consecutive patients over 60 years of age (mean age 64 +/- 4 years) and 231 patients younger than 60 years underwent cardiac valve replacement procedures. In the elderly group, aortic valve replacement was performed in nineteen patients, mitral valve replacement in thirty-three patients both aortic and mitral valve replacement in sixteen patients, and both mitral and tricuspid valve replacement in three patients. Aortocoronary bypass was performed in four and tricuspid annuloplasty in 19 patients simultaneously. Two patients were operated on emergency. As for preoperative status, 63 patients (88.7%) were in New York Heart Association (NYHA) Functional Class III or IV. Mechanical valves were implanted in all aortic position and 16 mitral position. Bioprosthetic valves were placed in 34 mitral position and 3 tricuspid position. Mean follow-up period was 42 +/- 33 months. The early mortality rate was 11% (8 patients) and the actuarial survival rate was 88 +/- 5% at five years and 74 +/- 10% at ten years. Postoperative functional improvement was excellent in 85.7% of the survivors. In the younger age group, 77.9% belonged to NYHA class III or IV preoperatively. The early mortality was 3.0% (7 patients) and the actuarial survival rate was 95 +/- 2% at five years and 86 +/- 2% at ten years. And postoperatively 91.3% were in NYHA class I or II. In conclusion, cardiac valve replacement in the elderly can be performed with an acceptable mortality and excellent functional improvement.     

Performance of glutaraldehyde-preserved porcine bioprosthesis as a mitral valve substitute in a young population group

Porcine bioprostheses were implanted in the mitral position in 289 patients. The mean age was 25.8 +/- 13.7 years. One hundred thirty-five patients (47%) were 20 years old or younger. Most patients had chronic rheumatic valvulitis (74%). Mitral regurgitation and mixed mitral valve disease were the dominant lesions. Hancock, Angell-Shiley, and Carpentier-Edwards prostheses were implanted in 84, 14, and 191 patients, respectively. There were 19 early and 64 late deaths. Mean follow-up was 5.04 +/- 1.03 patient-years. Fifty-eight patients (6.71% per patient-year) were reoperated on for degenerated prostheses, with 13 deaths. Twelve patients died without reoperation, and 17 await reoperation for degenerated valves. The rate of structural failure (total, 87 patients) was 21.07% and 3.04% per patient-year for patients less than and older than 20 years, respectively (p less than 0.001). The 6-year actuarial survival for these two groups was 50% and 68%, respectively. However, for patients 20 years old or younger, survival free from degeneration was only 20% at 6 years (p less than 0.001). Bioprostheses have a high failure rate and should not be implanted in young patients or in patients with a life expectancy exceeding 10 years.     

Long-term durability of the Hancock II porcine bioprosthesis

BACKGROUND: Survival and prosthetic complications of patients receiving the Hancock II second-generation bioprosthesis (Medtronic, Inc, Minneapolis, Minn) in the aortic, mitral, mitral-aortic, and tricuspid positions were analyzed at 15 years' follow-up. METHODS: Between May 1983 and December 1993, 212 patients (104 men and 108 women; mean age, 63 +/- 9 years; age range, 29-81 years) received 66 aortic, 114 mitral, 26 mitral-aortic, and 6 tricuspid Hancock II valves. Thirty-one percent of patients had previous valve operations, 15% had concomitant cardiac procedures, and 87% were in New York Heart Association class III or IV. Follow-up included 1704 patient-years and was 98% complete, with a median of 9 patient-years (range, 0.013-17.4 years). Forty-six patients were at risk at 14 to 15 years, and 30 were at risk after 15 years. RESULTS: One hundred twenty-two (57%) of 212 patients died, 20 of them perioperatively. Fifteen-year actuarial Kaplan-Meier survival was 35.2% +/- 3.8%, and freedom from valve-related mortality was 84% +/- 3.5%, with no difference on the basis of position or age (<65 or >or=65 years). Percentages for freedom from thromboembolism, anticoagulant-related hemorrhage, endocarditis, and paravalvular leak were, respectively, 78.2% +/- 4%, 83.5% +/- 3.6%, 95.7% +/- 2%, and 97.3% +/- 1.4%, with no significant difference between the aortic and mitral positions. Freedom from structural valve deterioration was 71.8% +/- 5.6%: 88.9% +/- 6.2% in the aortic position versus 59.5% +/- 3.9% in the mitral position (P =.01) and 64.3% +/- 3% in the mitral-aortic position. In patients younger than 65 years, actual freedom from structural valve deterioration was less than that seen in older patients (84.5% +/- 3.5% vs 95% +/- 3.0%) and was better in the aortic versus the mitral position (92% +/- 4.5% vs 82% +/- 4.2%). CONCLUSION: The Hancock II porcine valve showed excellent 15-year durability. We recommend its use in patients 65 years of age, as well as in younger patients undergoing aortic replacement.     

Survival and valve failure after aortic valve replacement.

A prospective evaluation of 412 consecutive patients undergoing isolated aortic valve replacement between January 1982 and December 1985 was performed in an attempt to identify the determinants of survival and valve failure. A variety of valves were inserted to permit a prospective evaluation of alternative valves including: Bj?rk-Shiley mechanical (n = 37), Ionescu-Shiley pericardial (n = 261), Hancock pericardial (n = 78), and Carpentier-Edwards porcine (n = 36). Thirteen patients died in the hospital (3.2%) and 47 patients died in the follow-up period producing an actuarial survival of 81% +/- 3% at 48 months. Survival was independently predicted by advancing age, preoperative New York Heart Association functional class, and the presence of endocarditis (p less than 0.05 by Cox regression analysis). The majority of patients were symptomatically improved (New York Heart Association class I or II: 21% preoperative, 88% postoperative). Freedom from structural valve dysfunction, prosthetic valve endocarditis, and reoperation for valve-related complications were 95% +/- 2%, 95% +/- 2%, and 92% +/- 2% at 48 months, respectively. These valve-related complications occurred more frequently in younger patients and in those with a Hancock pericardial valve (freedom from structural valve dysfunction, 89% +/- 5%; prosthetic valve endocarditis, 84% +/- 9%; reoperation, 78% +/- 10%; p less than 0.05 by Cox regression). Freedom from thromboembolism was 88% +/- 2% at 48 months; it was significantly lower in patients with a preoperative thromboembolic event and was not influenced by the type of prosthesis inserted. Freedom from anticoagulant-related hemorrhage was 85% +/- 8% at 48 months and was not influenced by any preoperative factors.(ABSTRACT TRUNCATED AT 250 WORDS)