A. Ian Munro

Carpentier-Edwards standard porcine bioprosthesis: a 21-year experience

BACKGROUNDnThe Carpentier-Edwards standard porcine bioprosthesis experience to 21 years has been evaluated to determine the influence of structural valve deterioration by valve position in various age groupings.nnnMETHODSnFrom 1975 to 1988, 1,181 patients had the prosthesis implanted in 1,198 procedures. The mean age of the population was 57.9+/-12.5 years (range, 21 to 85 years). Aortic valve replacement was performed in 564 patients (47.8%); mitral valve replacement, 478 (40.5%); and multiple valve replacement, 132 (11.2%). Concomitant procedures were performed in 337 patients (28.5%), and 140 (11.9%) had previous operations.nnnRESULTSnThe early mortality was 8.1% (97), only 0.4% (5) of which were valve-related. The total follow-up was 10,405 years (mean, 8.8+/-5.2 years). The late mortality was 5.7%/patient-year (591), with the valve-related component 1.6%/patient-year (168) with a 13% reoperative mortality (56). The linearized rate of structural valve deterioration was 3.8%/patient-year (395), with overall complications of 7.1%/patient-year (737). The overall survival at 20 years was 17.2%+/-3.1% (p < 0.05; aortic valve replacement greater than mitral valve replacement or multiple valve replacement). The freedom from structural valve deterioration was, at 18 years, 25.8%+/-2.8% overall, AVR 40.6%+/-4.2%, and MVR 8.5%+/-3.4% (p < 0.05, aortic valve replacement greater than mitral valve replacement or multiple valve replacement). The freedom from structural valve deterioration for aortic valve replacement was, at 15 years, for patients older than 70 years, 82.9%+/-9.1%; 61 to 70 years, 73.2%+/-4.7%; 51 to 60 years, 58.8%+/-5.4%; 41 to 50 years, 41.7%+/-8.2%; and 21 to 40 years, 25.5%+/-7.8%. The freedom from structural valve deterioration for mitral valve replacement was, at 15 years, for patients older than 70 years, 89.8%+/-7.6%; 61 to 70 years, 22.8%+/-6.3%; 51 to 60 years, 26.3% +/- 5.7%; 41 to 50 years, 11.7%+/-5.6%; and 21 to 40 years, 7.0%+/-4.7%.nnnCONCLUSIONSnThe prosthesis is recommended for aortic valve replacement for patients older than 70 years and for patients 61 to 70 years (when extended longevity is not anticipated) and for mitral valve replacement for patients older than 70 years.

Reoperation in biological and mechanical valve populations: Fate of the reoperative patient

From 1975 through 1992 inclusive, reoperative valve replacement (REOP) was required by 12.9% of patients (708/5,499). Of 1,355 patients with mechanical prostheses (MP), 46 (3.4%) came to REOP versus 662 of 4,144 patients (16%) with biological prostheses (BP). Early REOP mortality rate was 17.4% (8/46) for MP and 10.6% (70/662) for BP (p = not significant). It was higher with age greater than 75 years (p < 0.05) and trended higher with concomitant procedures and with increasing number of REOPs (p = not significant). The percentage freedom from REOP at 5 and 10 years for all BP was 96.0% +/- 0.4% and 74.9% +/- 1.1% compared with 93.6% +/- 1.2% and 87.9% +/- 2.5% for MP. The most common cause of REOP in the BP patients was structural valve deterioration, which was uncommon in patients with MP (72% versus 2% of REOP but only 15% versus 0.1% of initial implants). Nonstructural dysfunction was the leading cause of REOP in the MP group (65% versus 11%). Prosthetic valve endocarditis (18% versus 10%) and thromboembolic complications (10% versus 1%) were also more frequent causes of REOP in MP patients. However, the increased relative role of these factors with MP is due to the minimal incidence of structural valve deterioration. When related to the original choice of MP versus BP, only thromboembolic complication (3.8 times) was more prevalent as a cause of REOP in patients receiving MP at their previous procedure (p = not significant). For patients who previously received BP, structural valve deterioration (69 times) was more likely to lead to REOP than with MP (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Pregnancy and bioprostheses: Influence on structural valve deterioration**

The long-term performance of bioprostheses was evaluated in women 35 years of age or less to determine the influence of pregnancy on structural valve deterioration. Between 1972 and 1992, 237 female patients received 255 biological prostheses. Of the total operations, 53 were performed in patients who experienced pregnancy (P) and 202 in patients who were never pregnant (nonpregnant [NP]). The mean age of the P group was 23.0 +/- 5.8 years (standard deviation) (12 to 34 years) and of the NP group it was 27.1 +/- 6.3 years (8 to 35 years) (p < 0.05). The mean follow-up for the NP group was 6.8 years and for the P group it was 7.9 years. The late mortality was 2.26%/patient-year overall, 2.71%/patient-year for the NP group and 0.89%/patient-year for the P group (p = not significant [NS]). The P group of 52 patients had 94 pregnancies: 70 deliveries (74.5%) and 24 abortions (25.5%) (therapeutic, 14 [15%]). There were a total of 143 valve-related complications (P, 35; NP, 108); the majority for structural valve deterioration (SVD) 43% (109 patients), P 51% (27 patients) and NP 41% (82 patients) (p = NS). The valve-related reoperation rate paralleled the SVD rate at 42% (107 patients), P 51% (27 patients) and NP 40% (80 patients) (p = NS). The overall reoperative mortality rate was 6.0%. The interval from initial implant to reoperation was 99.6 +/- 3.6 months (p = NS groups P and NP).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac valve replacement in the elderly: Clinical performance of biological prostheses

From 1975 to 1987, 1,127 elderly patients underwent 1,223 valve replacements with the Carpentier-Edwards standard or supraannular porcine bioprostheses in 1,147 operations. Of the total patient population seen during these years, 33.5% receiving a standard porcine bioprosthesis and 48.6% receiving a supraannular bioprosthesis were 65 years of age or older. Of this elderly patient population, 465 patients were between 65 and 69 years old; 618 patients, 70 and 79 years old; and 52 patients, 80 years old and older. Aortic valve replacement was performed in 635 patients, mitral valve replacement in 417 patients, tricuspid valve replacement in 2 patients, and multiple-valve replacement in 80 patients. The cumulative follow-up was 3,957 patient-years. Early mortality was 9.5%: 7.3% for the 65- to 69-year-old group, 10.7% for the 70- to 79-year-old group, and 15.4% for the group 80 years old and older. Late mortality was 5.5% per patient-year: 4.2% per patient-year for the 65- to 69-year-old group, 6.3% per patient-year for the 70- to 79-year-old group, and 14.1% per patient-year for the group 80 years old and older. Valve-related causes contributed to 7 early deaths and 33 late deaths. The overall patient survival, including operative deaths, was 70.7% +/- 1.6% at 5 years and 47.8% +/- 3.7% at 10 and 12 years. The freedom from all valve-related complications was 52.1% +/- 6.1% at 10 and 12 years. The overall rate of valve-related complications was 5.0% per patient-year (fatal complications, 1.13% per patient-year). The overall rate of thromboembolism was 2.3% per patient-year and the freedom from thromboembolism, 69.6% +/- 5.2% at 10 and 12 years. The freedom from structural valve deterioration was 80.8% +/- 8.1% at 10 and 12 years: 71.7% +/- 11.0% at 10 and 12 years for the 65- to 69-year-old group, 97.9% +/- 1.2% at 10 years for the 70- to 79-year-old group, and 100% at 12 years for the group 80 years old and older. At 10 and 12 years, the freedom from valve-related death was 83.7% +/- 4.3% and the freedom from reoperation, 73.3% +/- 8.6%. The freedom from valve-related death, residual morbidity from thromboembolism and anticoagulant-related hemorrhage, and reoperation was 61.7% +/- 7.0% at 10 and 12 years. The clinical performance of porcine bioprostheses in the elderly patient population has been excellent. The early mortality increases in patients 70 years old or older.(ABSTRACT TRUNCATED AT 400 WORDS)

Porcine bioprostheses in the elderly: Clinical performance by age groups and valve positions

Porcine bioprostheses have been recommended and used for cardiac valve replacement in the elderly. A review of 1,984 patients with 2,042 operations, performed between 1975 and 1992, has afforded a detailed evaluation of clinical performance by valve positions and age groups within the elderly population. The numbers of operations performed by age groups were 65 to 69 years, 719; 70 to 74 years, 745; 75 to 79 years, 431; 80 to 84 years, 119; and 85 years or older, 28. The early mortality rate overall was 9.5% (195 patients), range 6.9% to 17.8% by age groups (p < 0.05), and 11.9% with concomitant procedures and 7.6% without (p < 0.05). The total cumulative follow-up was 10,060 patient-years (mean, 4.9 years). The late mortality rate was 7.0%/patient-year (for age groups, 5.8% to 13.4%/patient-year) (p = not significant). The patient survival at 15 years ranged from 25% +/- 4% for 65 to 69 years to 9% +/- 5% for 75 to 79 years (p < 0.05). The freedom from valve-related complications and composites at 10 years revealed differences (p < 0.05) by age groups only for structural valve deterioration: 85% +/- 2% for 65 to 69 years versus 98% +/- 2% for 80 to 84 years. The overall freedom from structural valve deterioration at 10 years for aortic valve replacement was 98% +/- 1%; for mitral valve replacement, 79% +/- 3%; and for multiple replacement, 86% +/- 7% (p < 0.05, aortic valve replacement > mitral valve replacement).(ABSTRACT TRUNCATED AT 250 WORDS)

Tricuspid valve replacement: Porcine bioprostheses and mechanical prostheses

The clinical performance of tricuspid valve replacement with bioprostheses and mechanical prostheses was assessed in a series of 5,489 total valve replacement operations performed from 1975 to 1992. There were 97 (1.8%) tricuspid valve replacements in 94 patients (16 men, 78 women) with a mean age of 55.4 +/- 13.8 years. Bioprostheses (mean patient age, 55.9 +/- 14.1 years) were used in 83 operations and mechanical prostheses (mean patient age, 52.1 +/- 11.9 years) were used in 14 operations. There were 30 isolated tricuspid valve replacements and 67 tricuspid valve replacements incorporated in multiple valve replacements. The total cumulative follow-up was 360 patient-years (bioprostheses, 321 years; mechanical prostheses, 39 years) (96.8% complete). The mean follow-up was 3.7 years (bioprostheses, 3.9 years; mechanical prostheses, 2.8 years) (p = not significant). The early mortality was 14.4% (bioprostheses, 14.5%; mechanical prostheses, 14.3%) (p = not significant) (isolated replacement, 13.3%; multiple replacement, 14.9%). The late mortality was 9.2% per patient-year (isolated replacement, 12.2% per patient-year; multiple replacement, 7.9% per patient-year). The freedom from structural valve deterioration at 5 and 7 years was 100% for mechanical prostheses and 97.1% +/- 2.9% for bioprostheses (p = not significant). For isolated tricuspid valve replacement, the freedom from structural valve deterioration for bioprostheses was 90.9% +/- 8.7% at 5 years and at 7 years (p = not significant). For the mechanical prostheses, the freedom was 100%.(ABSTRACT TRUNCATED AT 250 WORDS)

Experience with the Carpentier-Edwards Porcine Valve Prosthesis in 700 Patients

The Carpentier-Edwards porcine valve prosthesis has afforded our patients a satisfactory quality of life and a low incidence of valve-related complications at follow-up periods of up to five years. From December, 1975 to March, 1980, 768 prosthesis were implanted in 700 patients (aortic valve replacement [AVR], 334; mitral valve replacement [MVR], 292; tricuspid valve replacement [TVR), 6; and multiple valve replacement, 68). One hundred and thirty-seven patients (19.6%) had had previous cardiac operations. Concomitant aortocoronary bypass was performed in 127 patients (18.1%). There were 52 hospital deaths, for a mortality of 7.4% (AVR, 4.8%; MVR, 9.2%; multiple valve replacement, 11.8%). Total follow-up was 1,047 patient-years (range, 6 to 60 months, mean, 19.4 months). There were 33 late deaths (AVR, 1.7% per patient-year; MVR, 4.0% per patient-year; multiple valve replacement, 8.1% per patient-year). Eight percent of AVR patients and 47% of MVR and multiple valve replacement patients were taking anticoagulants. The valve-related complications (expressed as events per 100 patient-years) were as follows: (1) thromboembolism (AVR, 0.94; MVR,. 1.42; multiple valve replacement, 4.62); (2) infective endocarditis (AVR, 0.94; MVR, 0.24; multiple valve replacement, 2.31); (3) periprosthetic leak (AVR, 0.94; MVR, 0.71; multiple valve replacement, 3.46); and (4) valve dysfunction (MVR, 0.24). The only case of valve dysfunction was a calcified mitral prosthesis in a 13-year-old girl. Actuarial survival, including operative deaths, was as follows: AVR, 90.5% at 36 months; MVR, 84% at 36 months; and multiple valve replacement, 74% at 24 months. Of surviving patient, 93.6% were in New York Heart Association Class I or II at follow-up evaluation.

Medtronic intact porcine bioprosthesis experience to twelve years

BACKGROUNDnThe Medtronic Intact porcine bioprosthesis was further evaluated to determine the influence of zero-pressure glutaraldehyde fixation on structural valve deterioration (SVD).nnnMETHODSnFrom 1986 through 1996, at three Canadian centers, 1,272 patients had 1,296 procedures: 836 aortic valve replacement (AVR), 332 mitral valve replacement (MVR), 14 tricuspid valve replacement, 3 pulmonary valve replacement, and 111 multiple valve replacements. The mean age of the patient population was 67 years (range 9 to 91 years). The total follow-up was 8,011 patient-years (mean 6.2 years).nnnRESULTSnThe late mortality (overall) was 4.8% and 6.7% per patient-year for AVR with or without concomitant procedures, respectively; and 4.7% and 10.4% per patient-year for MVR, respectively. There were 51 cases of SVD (AVR 22 of 836; MVR 23 of 332; pulmonary valve replacement 1 of 3; and multiple valve replacement 5 of 111). The actuarial freedom from SVD at 12 years for AVR was 94.3%+/-3.3% for patients aged 61 to 70 years and 97.7%+/-1.1% for those more than 70 years; for MVR actuarial freedom from SVD at 12 years was 93.7%+/-3.9% for patients more than 70 years. The actual freedom at 12 years from SVD for AVR was 92.4%+/-3.1% for patients aged 51 to 60 years, 96.1%+/-2.1% for those 61 to 70 years, and 98.4%+/-0.7% for those older than 70 years; for MVR actual freedom from SVD at 12 years was 89.6%+/-3.2% for patients 61 to 70 years and 96.6%+/-3.4% for those more than 70 years.nnnCONCLUSIONSnThe Medtronic Intact porcine bioprosthesis, formulated with tissue preservation at zero-pressure fixation, has encouraging freedom from structural failure.

Carpentier-Edwards standard and supraannular porcine bioprostheses: comparison of technology

BACKGROUNDnPerformance with regard to structural valve deterioration (SVD) with the Carpentier-Edwards standard (CE-S) and supraannular (CE-SAV) (Baxter Healthcare Corp, Irvine, CA) porcine bioprostheses was evaluated to determine whether progress in reduction of structural failure has been achieved with technological changes.nnnMETHODSnThe CE-S was implanted during 567 aortic valve replacement (AVR) and 486 mitral valve replacement (MVR) procedures, and the CE-SAV was implanted during 1,670 AVR and 1,096 MVR procedures. The failure mode of early stent dehiscence with the CE-SAV prosthesis, thought to be controlled by manufacturing changes in 1986 and 1987, supported comparison of the CE-SAV with censored cases of stent dehiscence. Stent dehiscence accounted for only 1.2% (1 of 81) and 14.1% (29 of 205) of AVR and MVR CE-SAV failures, respectively.nnnRESULTSnThe only difference for AVR for freedom from SVD occurred in the 21- to 40-year age group at 15 years and was 68% for the CE-SAV and 31% for the CE-S (p<0.05). In the 61- to 70-year age group, freedom from SVD at 15 years was 76% for the CE-S and 84% for the CE-SAV; for the 71-year or higher age group, freedom from SVD was 89% and 95%, respectively (p = NS). For MVR freedom from SVD was different only in the 71-year or higher age group and was 90% for the CE-S and 59% for the CE-SAV (p<0.05). Freedom from SVD was reduced but was similar (p = NS) for the other age groups. For AVR the actual freedom from SVD at 15 years for the CE-S and CE-SAV was, respectively, 79% and 72% for the 51- to 60-year age group, 86% and 91% for the 61- to 70-year age group, and 98% and 98% for the 71-year or higher age group. For MVR, these rates were, respectively, 69% and 75% for the 61- to 70-year age group and 96% and 89% for the 71-year and higher age group.nnnCONCLUSIONSnThe technologic advancements made in the second-generation CE-SAV bioprosthesis to reduce the incidence of structural failure have not uniformly been successful. The actual freedom from SVD provides evidence for implantation of porcine bioprostheses for AVR in age groups 61 to 70 years and 71 years or higher and for MVR in the age group 71 years or higher.

Medtronic intact porcine bioprosthesis: 10 years’ experience

BACKGROUNDnThe Medtronic Intact porcine bioprosthesis experience was evaluated over a period of 10 years to determine the influence of structural valve deterioration by valve position in various age groupings.nnnMETHODSnFrom 1986 to 1996 inclusive, at three centers, 1,272 patients had the prosthesis implanted in 1,296 procedures. The mean age of the population was 67 years (range, 9 to 91 years). There were 836 aortic valve replacements (AVR) (64.5%), 333 mitral valve replacements (MVR) (25.7%), and 110 multiple valve replacements (MR) (8.5%).nnnRESULTSnThe early mortality was 7.3% (94 of 1,296 procedures). The early mortality with concomitant procedures (primarily coronary artery bypass grafting) was 9.8% (52 of 528) and without, 5.5% (42 of 768). The late mortality was 4.25%/patient-year. The linearized rate of major thromboembolism was 0.86%/patient-year. The rate of reoperation was 1.19%/patient-year and valve-related mortality, 1.06%/patient-year. There were 36 cases of structural valve deterioration for aortic valve replacement (16), mitral valve replacement (15), tricuspid valve replacement (2), and multiple valve replacement (3). The freedom from structural valve deterioration for aortic valve replacement was in patients 21 to 40 years, 62.5%+/-25.8% at 7 years; 41 to 50 years, 75.0%+/-15.3% at 7 years; 51 to 60 years, 91.0%+/-4.5% at 8 years; 61 to 70 years, 98.7%+/-0.7% at 10 years; and older than 70 years, 98.3%+/-1.0% at 10 years (p < 0.05). The freedom from structural valve deterioration for mitral valve replacement was for patients 41 to 50 years, 91.7%+/-8.0% at 7 years; 51 to 60 years, 85.9%+/-9.9% at 8 years; 61 to 70 years, 86.3%+/-6.8% at 8 years; and older than 70 years, 93.9%+/-4.8% at 8 years (not significant).nnnCONCLUSIONSnThe Medtronic Intact porcine bioprosthesis has acceptable freedom from structural valve deterioration in both the aortic and mitral positions approaching 10 years of evaluation.