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.     

Carpentier-Edwards supra-annular porcine bioprosthesis. Clinical experience and implantation characteristics

The investigational Carpentier-Edwards supra-annular valve was implanted in 592 patients from November, 1981, to February, 1984 (aortic valve replacement in 286, mitral valve replacement in 259, and multiple valve replacement in 47, for a total of 638 prostheses). A previous cardiac operation had been performed in 77 patients (13%). Concomitant procedures were performed in 202 patients (34.1%), including coronary artery bypass in 163 patients. The patient evaluation was 98.6% complete. The early mortality was 7.4% (44 patients) and the late mortality was 6.2% per patient-year (41 patients). The valve-related causes of late mortality were thromboembolism (five), anticoagulant-related hemorrhage (one), and prosthetic valve endocarditis (one). The overall patient survival, including operative death, was 85% at 2 years. The linearized occurrence rate for valve-related complications was 5.6% per patient-year (37 events)--thromboembolism 2.7% per patient-year (18) anticoagulant-related hemorrhage 1.2% (eight), prosthetic valve endocarditis 0.8% (five), and periprosthetic leak 0.9% per patient-year (six). There were no cases of primary tissue failure or structural failure. At 2 years, the freedom from valve-related complications was 86.9%, from valve-related mortality, 98.7%, and from valve-related mortality and reoperation, 97.7%. This valve is fixed in glutaraldehyde at low pressure and is designed to improve durability. It has provided a low incidence of valve-related complications without structural failure. The structural design of the prosthesis does not always conform to the anatomy of bicuspid aortic valves.     

The Carpentier-Edwards standard porcine bioprosthesis. A first-generation tissue valve with excellent long-term clinical performance

The Carpentier-Edwards standard porcine bioprosthesis was implanted in 1190 patients (1201 operations, 1303 valves) between January 1975 and June 1986; most implants were before 1982. The mean age of the patients was 57.2 years (range 8 to 85 years). The early mortality was 7.6% (aortic valve replacement 5.1%, mitral valve replacement 8.8%, and multiple valve replacement 15.3%). Late mortality was 3.9% per patient-year (aortic valve replacement 3.6%, mitral valve replacement 4.2%, and multiple valve replacement 3.8%). The total cumulative follow-up period was 6737 years. Thromboembolism was 1.5% per patient-year (fatal 0.4% per patient-year) (minor 0.6%, major 0.9%); antithromboembolic therapy-related hemorrhage was 0.5% (fatal 0.1%); prosthetic valve endocarditis was 0.6% (fatal 0.2%); nonstructural dysfunction was 0.5% (fatal 0.2%); and structural valve deterioration and/or primary tissue failure was 1.5% per patient-year (fatal, 0.2% per patient-year). Thromboembolism and structural valve deterioration were the significant complications, structural valve deterioration occurring primarily between the sixth and 10th year of evaluation. The overall patient survival was 65.0% for aortic valve replacement and 54.8% for mitral valve replacement (p less than 0.05) at 10 years. The patients were classified as 92.9% New York Heart Association functional classes III and IV preoperatively and 92.3% classes I and II postoperatively. Freedom at 10 years from thromboembolism was 84.3% for aortic valve replacement and 76.5% for mitral valve replacement (p = 0.05); structural valve deterioration was 78.6% for aortic valve replacement and 71.6% for mitral valve replacement (p less than 0.05); reoperation was 74.4% for aortic valve replacement and 67.1% for mitral valve replacement (p less than 0.05). Freedom from all valve-related complications at 10 years was 58.9% for aortic valve replacement and 46.8% for mitral valve replacement (p less than 0.05); valve-related mortality was 89.5% for aortic valve replacement and 82.6% for mitral valve replacement (p = not significant); mortality and reoperation was 58.9% for aortic valve replacement and 46.8% for mitral valve replacement (p less than 0.05); mortality and residual morbidity (treatment failure) was 87.2% for aortic valve replacement and 75.1% for mitral valve replacement (p = not significant); mortality, residual morbidity, and reoperation were 66.3% for aortic valve replacement and 54.9% for mitral valve replacement (p less than 0.05). The standard Carpentier-Edwards porcine bioprosthesis has provided satisfactory clinical performance and has afforded patients excellent quality of life.     

Durability and low thrombogenicity of the St. Jude Medical valve at 5-year follow-up

Between November, 1978, and December, 1983, 736 patients had valve replacement with the St. Jude Medical valve prosthesis. There were 478 patients with aortic valve replacement (AVR), 188 with mitral valve replacement (MVR), 63 with double valve replacement, and 7 with tricuspid valve replacement (they were not included in this study). The mean age at the time of operation was 46.7 years for patients having AVR and 48.6 years for those having MVR and AVR + MVR. Follow-up totaled 1,116 patient-years (range, 4 to 82 months). Early (30-day) mortality was lowest for isolated MVR (2.3%) and AVR (3.7%), and increased with reoperation or when associated procedures were combined with valve replacement. Patients undergoing reoperation or having associated procedures made up 49% of the AVR and 54% of the MVR groups. All patients were advised of the need for long-term anticoagulation with warfarin sodium. Nine patients (7 with AVR, 1 with MVR, 1 with AVR + MVR) had suspected or confirmed episodes of systemic thromboembolism, a linearized incidence of 0.99% per patient-year for AVR, 0.36% per patient-year for MVR, and 0.98% per patient-year for AVR + MVR. Eight patients with AVR underwent reoperation for prosthetic valve endocarditis (5 of the 8 patients had endocarditis prior to initial valve replacement). There were no instances of structural valve failure. There were 37 late deaths. Actuarial survival at 5 years (excluding early mortality, 95% confidence limits) was 89.8% for AVR, 84.8% for MVR, and 95.2% for AVR + MVR.(ABSTRACT TRUNCATED AT 250 WORDS)     

Valve replacement in the elderly. Is the mechanical valve a good alternative?

The controversy surrounding the choice of a prosthesis for valve replacement in the elderly patient prompted me to review the performance of mechanical (Medtronic Hall [Medtronic, Inc., Minneapolis, Minn.] and St. Jude Medical [St. Jude Medical, Inc., St. Paul, Minn.]) valves implanted in 213 patients 65 years and older (mean 70.4 years) from 1980 to 1985. There were 63 mitral, 131 aortic, and 19 double (aortic and mitral) valve replacements. Most patients undergoing aortic valve replacement had stenotic lesions, but half of the patients in the mitral valve replacement group had regurgitation with or without stenosis. Early mortality rates for mitral, aortic, and double valve replacement were 4.8%, 6.1%, and 21.1%, respectively (p less than 0.01). The mortality rate for patients 65 to 74 years old was 6.5% and that for those older than 75 years was 9.1%. The cumulative follow-up for the survivors was 850 patient-years. The late mortality rate was 8.1% per patient-year but was valve-related in only 1.3% per patient-year. Noncardiac causes accounted for 43.5% of the late deaths. The late mortality rate was significantly higher in patients who had regurgitant lesions than in those who had stenotic or mixed disease. It was also higher in the older patients (10.3% per patient-year) than in the younger group (7.6% per patient-year; p less than 0.05). Reoperation was required in only six patients (0.7% per patient-year). Thrombotic obstruction of the prosthesis and systemic thromboembolism occurred at linearized rates of 0.6% per patient-year and 2.5% per patient year, respectively, and significant anticoagulant-related hemorrhage at a rate of 0.6% per patient-year. With the exception of late mortality, the incidence of all late complications was similar to that of patients younger than 65 years operated on during the same period. Actuarially, global survival (58% +/- 4%) and freedom from reoperation (95% +/- 2%), from thrombotic obstruction (96% +/- 1%), from thromboembolism (92% +/- 2%), from all valve-related mortality and morbidity (82% +/- 3%), and from valve failure (93% +/- 2%) were also similar to those of the younger patients. Mechanical prostheses perform well in elderly patients. I could not confirm an increase in thromboembolic or hemorrhagic episodes, and the respective mortality and morbidity indexes were similar to those observed in younger patients.     

Mitral Valve Replacement with the Hancock Bioprosthesis: Five- to Ten-Year Follow-up

One hundred eleven patients undergoing mitral valve replacement, either alone (56) or in conjunction with another type of prosthetic valve, prior to 1975 were evaluated. Hospital mortality was 9.9%. Cumulative follow-up is 505 patient-years (mean, 5.4 years). Seventy patients have been followed between 5 and 10 years. Late mortality for mitral valve replacement alone is 4.3 ± 1.3% per patient-year; actuarial survival is 82 ± 6% at 5 years and 65 ± 11% at 10 years. The incidence of emboli was 3.3 ± 0.9% per patient-year for all patients with bioprostheses (62) and 4.2 ± 1.7% per patient-year for bioprostheses and concomitant mechanical aortic valves (32). In patients with only bioprostheses, two of twelve emboli occurred within the first 6 postoperative months and there were three fatal cerebral emboli (0.8 + 0.5% per patient-year). The incidence of hemorrhagic complications is 4.9 ± 1.9% for anticoagulated patients with bioprostheses and mechanical aortic valves; one hemorrhage was fatal (0.7 ± 0.7% per patient-year). Intrinsic mitral bioprosthesis failure occurred in 10 patients; 2 died. Five patients had valve failure secondary to perivalvular regurgitation (3) or endocarditis (2). Actuarial late survival free from intrinsic mitral bioprosthetic failure was 99 ± 1% at 5 years, 92 ± 4% at 7 years, 70 ± 12% at 9 years, and 61 ± 13% at 10 years.It is unknown at the present time whether the long-term risk of late intrinsic valve failure and reoperation will outweigh the low incidence of emboli and avoidance of anticoagulant-related hemorrhage. Until further information becomes available, the Hancock bioprosthesis is used for mitral valve replacement only in patients older than 60 years or in patients with contraindications for anticoagulant therapy.     

Clinical performance of St. Jude and Medtronic-Hall prostheses: a randomized comparative study

Newer and improved models of mechanical prostheses are regularly added to surgeons' armamentarium. This study was designed to compare the clinical performance of two of the most used current models of mechanical prostheses. From August 1983 through July 1985, 182 white patients were prospectively randomized to implantation of the St. Jude Medical (95 patients) or Medtronic-Hall (87 patients) prostheses. There were 84 mitral, 85 aortic, and 13 double (mitral and aortic) valve replacements. There were no differences between the two groups with regard to sex distribution, age, functional class, emergency operation, and site of implantation. Early mortality was 3.2% for patients with the St. Jude valve and 5.7% for those with the Medtronic-Hall (p = NS). The survivors were followed for 3 to 5 years (mean, 4.2 +/- 0.6 years; cumulative follow-up, 559 patient-years). Late mortality was 7.1%/patient-year for the St. Jude group and 3.2%/patient-year for the Medtronic-Hall group (p less than 0.05). However, the valve-related mortality was equal (1.4%/patient-year) for both groups. Noncardiac causes accounted for most of the difference between the St. Jude and Medtronic-Hall groups (2.5%/patient-year and 0.4%/patient-year, respectively). There were no cases of thrombotic obstruction, whereas serious systemic thromboembolism occurred at the rate of 1.8%/patient-year (5 episodes) for the St. Jude group and 2.5%/patient-year (7 episodes) for the Medtronic-Hall group (p = not significant); there were another nine episodes of systemic embolism that left no sequelae. Three patients (St. Jude, 2; Medtronic-Hall, 1), all of whom had aortic valve replacement, required reoperation (0.5%/patient-year) because of prosthetic endocarditis, with two deaths.(ABSTRACT TRUNCATED AT 250 WORDS)     

Eight years' experience with the Medtronic-Hall valve prosthesis

During the period January 1981 to September 1986, 444 Medtronic-Hall heart valve prostheses were implanted in 351 patients (mean age, 45 +/- 10 years) mainly for rheumatic valve disease (63.2%). Most of the patients were in New York Heart Association functional class III. Concomitant surgical procedures, mainly conservative tricuspid or mitral procedures or coronary artery bypass grafting, were performed in 101 patients (28.7%). Single-valve replacement was performed in 262 patients (74.6%) (aortic in 117 patients, mitral in 143, and tricuspid in 2), double-valve replacement in 85 (24.2%) (mitral and aortic in 83 and mitral and tricuspid in 2), and triple-valve replacement in 4 (1.1%). Hospital mortality was 6.2%. Follow-up was 97.7% complete. The overall actuarial 8-year survival rate was 77.2%. The linearized incidence of valve-related complications was as follows: thromboembolism, 1.5%/patient-year; reoperation, 1.5%/patient-year; endocarditis, 1.25%/patient-year; hemolysis, 0.52%/patient-year; anticoagulant-related hemorrhage, 0.39%/patient-year; and noninfection-related paraprosthetic leak, 0.33%/patient-year. There were no instances of structural failure. We conclude that after 8 years of follow-up, the Medtronic-Hall valve prosthesis has an excellent clinical performance and a low range of valve-related complications.     

The Carpentier-Edwards supraannular porcine bioprosthesis. A new generation tissue valve with excellent intermediate clinical performance

The Carpentier-Edwards supraannular porcine bioprosthesis, an investigational valve, was implanted in 1167 patients (1174 operations, 1274 valves) between November 1981 and December 1985 (age range 13 to 85 years, mean 61 years). The early mortality rate was 7.2% (with concomitant procedures 10.9%, without 4.8%; with previous operation 10.5%, without 6.6%). The late mortality rate was 4.5% per patient-year (aortic valve replacement, 4.0%; mitral valve replacement, 4.8%; multiple valve replacement, 5.6%). Total cumulative follow-up was 2272.3 years. The prevalence of thromboembolism was 2.6% per patient-year (fatal 0.4% per patient-year, major 1.4%, minor 1.2%); hemorrhage related to antithromboembolic therapy, 0.7% (fatal 0.1%); prosthetic valve endocarditis, 0.4% (fatal 0.2%); periprosthetic leak, 0.4% (fatal 0%); structural valve deterioration (primary tissue failure/structural failure), 0.1% per patient-year; and clinical valve dysfunction, 0.4%. The reoperation rate was 0.8% per patient-year (thromboembolism, 0.1%; clinical valve dysfunction, 0.1%; prosthetic valve endocarditis, 0.1%; periprosthetic leak, 0.4%; structural valve deterioration, 0.1%). Thromboembolism occurred throughout the observation period but with decreasing frequency, hemorrhage throughout the period in no predictable fashion, prosthetic valve endocarditis within 2 years, periprosthetic leak within 2 years, and structural valve deterioration occurred during the fourth year of assessment. The overall survival rate was 79.8% +/- 1.7% (4 years). Freedom (at 4 years) from thromboembolism was 92.2% +/- 1.2%; from structural valve deterioration, 98.8% +/- 0.8%; and from reoperation, 95.8% +/- 1.3%. Freedom from all complications (4 years) was 85.9% +/- 1.7%; from complication mortality, 98.4% +/- 0.4%; and from valve failure (mortality and reoperation), 94.3% +/- 1.3%. This investigational Carpentier-Edwards supraannular porcine bioprosthetic valve has provided excellent clinical performance and remains our overall prosthesis of choice.     

Implantation of the Duromedics bileaflet cardiac valve prosthesis in 400 patients

From September, 1983, to April, 1986, 451 Duromedics bileaflet cardiac valve prostheses were implanted in 400 patients at our institution in Vienna. Aortic valve replacement was done in 190 patients, 157 underwent mitral valve replacement (1 patient also underwent tricuspid valve replacement), 52 underwent double valve replacement, and 1 patient underwent isolated reoperation for tricuspid valve replacement. Concomitant procedures were performed in 86 patients (21.5%). Sixty-one patients (15.2%) had undergone previous cardiac surgery; 32 (8%) had undergone earlier valve replacement. The early mortality rate (within 30 days) was 6.25% (25 patients). Follow-up was done on 337 surviving Austrian citizens; this represents 429 patient-years. The late mortality rate was 2.1% per patient-year (9 patients). We observed paravalvular leak in 3 patients (0.7% per patient-year), thromboembolism in 4 (0.9%), prosthetic valve endocarditis in 5 (1.2%), and anticoagulant-related hemorrhage in 10 (2.3%). Valve failure occurred in 8 patients (1.8%). We conclude, therefore, that good clinical results and a low complication rate can be achieved with this new type of valve.     

Nine years' experience with the Bj?rk-Shiley prosthetic valve: early and late results of 932 valve replacements

Between November, 1970, and December, 1977, 932 consecutive patients received the standard Bj?rk-Shiley prosthesis. Operative mortality was 4.6% for aortic valve replacement (AVR; N = 364), 5.1% for mitral valve replacement (MVR; N = 313); 11.3% for multiple valve replacement (N = 194), and 13.7% for valve replacement combined with coronary artery bypass grafting (CABG; N = 51). Factors influencing hospital mortality included type of valve replacement, age at operation, whether the valve replacement was done as an emergency, and year of implantation. Complete follow-up (mean, 3.7 years) was achieved in 95% of the survivors. Actuarial survival was 82% for AVR patients at 8 years, 83% for MVR patients at 7 years, 72% for multiple valve replacement patients at 7 years, and 76% for those who had valve replacement with CABG at 3 years. No significant difference in late survival was found between patients with mitral insufficiency alone (p greater than 0.2) or aortic insufficiency alone (p greater than 0.9) and those with stenotic lesions only. Thromboembolic complications occurred at an incidence of 1.17% per patient-year, and Dicumarol-induced hemorrhages occurred at an incidence of 2.11% per patient-year. Twelve out of 13 patients survived operation for prosthetic valve thrombosis, indicating that this complication is not as catastrophic as many believe. The incidence of reoperation in anticoagulated patients was 0.63% per patient-year. All of these results are compared with data from the recent literature.     

Late results after left-sided cardiac valve replacement in children

Selection of types of cardiac valve substitutes for children remains controversial. Between 1976 and 1984, 166 children, 15 years of age or younger, underwent aortic (N = 53) or mitral valve replacement (N = 90) or both (N = 23). Biological prostheses were used in 84 patients and mechanical prostheses in 71; both a mitral bioprosthesis and an aortic mechanical valve were used in 11 patients. The overall early mortality was 9%. Mean follow-up intervals were 4.1 years for the bioprosthesis group, 3.3 years for the mechanical valve group, and 3.5 years for the group receiving both. The 7 year survival rates (+/- standard error) were 63% +/- 6% in the bioprosthesis group and 70% +/- 7% in the mechanical valve group (p = NS). After aortic valve replacement the 7 year survival rates were 66% +/- 14% (bioprosthesis group) and 77% +/- 9% (mechanical valve group) (p = NS); after mitral valve replacement the rates were 65% +/- 7% (bioprosthesis group) and 54% +/- 17% (mechanical valve group) (p = NS). The incidence of thromboembolic events was 0.6% +/- 0.4% per patient-year in the bioprosthesis group (none after aortic valve replacement, 0.8% +/- 0.6% per patient-year after mitral valve replacement) and 1.4% +/- 0.8% per patient-year in the mechanical valve group (0.7% +/- 0.7% per patient-year after aortic valve replacement, 4.0% +/- 2.8% per patient-year after mitral valve replacement) (p = NS). The linearized rates of reoperation were 10.4% +/- 1.8% per patient-year (bioprosthesis group) and 2.3% +/- 1.0% per patient-year (mechanical valve group) (p less than 0.001). The 7 year probability rates of freedom from all valve-related complications were 43% +/- 6% in the bioprosthesis group and 86% +/- 4% in the mechanical valve group (p less than 0.001). In the aortic position, a mechanical adult-sized prosthesis can always be implanted, and satisfactory long-term results can be anticipated. In the systemic atrioventricular position, the results are less than satisfactory with either type of prosthesis; every effort should be made to preserve the natural valve of the child.     

Long-term comparative analysis of the Bj?rk-Shiley and Hancock valves implanted in 1975

The long-term results in all patients undergoing isolated mitral, aortic, or double mitral-aortic heart valve replacement operated upon in 1975 has been retrospectively analyzed. A total of 153 patients received the standard Bj?rk-Shiley (flat pyrolytic disc) mechanical prostheses and 150 patients received the noncomposite Hancock porcine xenograft. Overall operative mortality was not significantly different between groups. All patients receiving a Bj?rk-Shiley prosthesis, but none in the Hancock group, received long-term anticoagulant therapy. Medium and long-term actuarial survival rates (5 and 10 years postoperatively) were comparable for the two groups (88% for Bj?rk-Shiley and 84% for Hancock [NS] at 5 years; 86% for Bj?rk-Shiley and 80% for Hancock at 10 years [NS]). The incidence of systemic embolism was similar in the two groups (1.6% +/- 0.4% per patient-year for the Bj?rk-Shiley group and 1.3% +/- 0.3% per patient-year for the Hancock group [NS]). Also the incidence of endocarditis was similar (0.6% +/- 0.2% per patient-year for the Bj?rk-Shiley group and 0.8% +/- 0.3% per patient-year for the Hancock group [NS]). In the Hancock group the overall incidence of reoperations was significantly higher than in the Bj?rk-Shiley group (4.2% +/- 0.6% per patient-year versus 0.9% +/- 0.3% per patient-year (p = 0.001). The major cause for reoperation in the Hancock group was primary tissue failure (3% +/- 0.5% per patient-year). In the Bj?rk-Shiley group the major cause of reoperation was valve thrombosis (0.5% +/- 0.2% per patient-year). Therefore, accepting the fact that other bioprostheses may behave differently from the Hancock noncomposite xenograft, we currently restrict our indications for valve replacement with bioprostheses.     

Ionescu-Shiley pericardial xenografts: follow-up of up to 6 years

The results of valve replacement with the Ionescu-Shiley pericardial xenograft compare favorably with results obtained with other bioprostheses. From March, 1977, to July, 1983, 497 Ionescu-Shiley pericardial valves were implanted in 463 patients at the University of Ottawa Heart Institute. There were 292 patients who had aortic valve replacement (AVR), 140 with mitral valve replacement (MVR), 28 with double valve replacement, and 3 with triple valve replacement. The survivors were followed regularly. Actuarial analysis of late results indicates an expected survival of 71% at 6 years for patients who underwent AVR and 72% at 3 years for patients who had MVR. The only valve-related deaths were due to endocarditis, which occurred at a rate of 3.9% per patient-year for aortic valves and 0.6% per patient-year for mitral valves. Despite a low usage of formal anticoagulation, embolic complications occurred at a rate of 1.4% per patient-year for aortic valves and 4.0% per patient-year for mitral valves. Five valves were removed for intrinsic failure after 36 to 72 months of follow-up. New York Heart Association Functional Class improved an average of 1.28 classes per patient.     

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.     

The Mitroflow pericardial bioprosthesis. Comparison of early clinical performance in aortic and mitral positions.

Between 1983 and 1987 the Mitroflow pericardial prosthesis was implanted in 354 patients, ranging in age from 14 to 94 years (mean 60.1 years). The early mortality was 5.7% and the late mortality 2.9% per patient-year. The total cumulative follow-up was 853 years (mean 2.4 years). Patient survival at 4 years for aortic valve replacement (AVR) was 81.5% and for mitral valve replacement (MVR) 74.8%. The overall rate of valve-related complications was 4.8% per patient-year (41 complications): thromboembolism, 15; hemorrhage related to antithromboembolic therapy, 1; prosthetic valve endocarditis, 15; nonstructural dysfunction, 3; and structural valve deterioration, 7. At 4 years the freedom from thromboembolism was 91.5% +/- 2.7% for AVR and 91.1% +/- 4.0% for MVR, from prosthetic valve endocarditis 93.5% +/- 2.3% for AVR and 94.0% +/- 2.9% for MVR, from structural valve deterioration 97.3% +/- 2.1% for AVR and 92.6% +/- 3.2% for MVR, from valve-related mortality 96.9% +/- 1.4% for AVR and 97.5% +/- 1.8% for MVR, and from reoperation 93.5% +/- 2.8% for AVR and 83.1% +/- 5.1% for MVR. The freedom from the composite of all valve-related complications at 4 years was 81.1% +/- 4.2% for AVR and 75.3% +/- 2.8% for MVR. The Mitroflow valve has provided satisfactory clinical performance at the 4-year evaluation. Structural valve deterioration is greater in the mitral position than in the aortic position. Long-term evaluation of the Mitroflow valve is necessary to determine the impact of structural valve deterioration on its clinical performance.     

复杂性感染性心内膜炎的外科治疗

目的评价瓣周脓肿、心肌脓肿以及瓣膜严重毁损等复杂性感染性心内膜炎手术治疗的近、远期疗效.方法回顾性分析1988年12月至2002年6月手术治疗的复杂性心内膜炎患者57例临床资料,均为原发性心内膜炎,其中感染侵犯主动脉瓣25例、二尖瓣16例、二尖瓣和主动脉瓣16例.术中发现瓣叶严重毁损32例、主动脉瓣周脓肿19例、主动脉根部环形脓肿导致左心室-主动脉连接破坏4例、二尖瓣后瓣环脓肿11例、心肌脓肿6例、瓣膜赘生物形成55例.脓肿清除后遗留残腔采用间断褥式缝合6例、自体心包片修补19例、牛心包片修补6例、聚四氟乙烯膨体补片修补4例;施行以带瓣管道作升主动脉根部替换和左、右冠状动脉移植术4例,主动脉瓣替换术21例,二尖瓣替换术16例,主动脉瓣及二尖瓣双瓣替换术16例.结果早期死亡6例(11%),死亡主要原因为低心输出量综合征、人造心脏瓣膜性心内膜炎和多脏器功能衰竭.随访4个月至14年,平均(5.93±0.20)年.晚期死亡5例,晚期主要并发症为人造瓣膜性心内膜炎.术后1年心功能恢复NYHA分组Ⅰ～Ⅱ级占96%(44/46);5年再手术免除率为(84±3)%,5年实际生存率为(61±9)%.结论复杂性心内膜炎局部组织破坏较多,应限期手术或急症手术,清创后残腔的处理是影响手术本身能否成功以及术后近、远期效果的关键.     

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 prostheses 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 patients, 93.6% were in New York Heart Association Class I or II at follow-up evaluation.     

The Bj?rk-Shiley valve prosthesis. Analysis of long-term evolution.

The long-term follow-up of 831 patients who underwent valve replacement with Bj?rk-Shiley Delrin and standard Pyrolyte prostheses (341 aortic, 345 mitral, and 145 mitroaortic) between 1971 and 1980 is reviewed. The follow-up concluded in 1985. Cumulative follow-up amounted to 4724 years, with a mean of 5.68 years per patient. Data on survival were obtained in 754 patients (complete follow-up in 90.8% of cases). Perivalvular leak was the most frequent complication in aortic valve replacement, whether isolated or combined, with values significantly higher than those registered in isolated mitral replacement (p < 0.001 in both cases). No correlation was found between this complication and valve calcification, but it was statistically correlated with the size 19 model (p < 0.05). Prosthetic stenosis was more common in mitral than in aortic replacement (p < 0.001), and of the former, size 23 was that most often affected (p < 0.001). The earliest case of mitral pannus was diagnosed 20 months postsurgery, and from 45 months on this pathology was the cause of every case of stenosis. The risk of thromboembolism was similar in aortic, mitral, and double prostheses, while it was the single most frequent complication in isolated mitral replacement. Prosthetic thrombosis was triggered in all cases in which it occurred by discontinuance of anticoagulant therapy. Anticoagulant-induced hemorrhages were more frequent in double replacement than in mitral (p < 0.05) and aortic valve replacement. Endocarditis was the complication that produced the highest mortality rate in all groups; the frequency of this infection was higher among patients with double prostheses when compared with either aortic replacement (p < 0.05) or mitral replacement (p < 0.001). The risk of suffering endocarditis was correlated with the existence of active preoperative infection in patients with mitral prostheses and double prostheses (p < 0.001 in both cases). Overall morbidity was higher in the double replacement group with respect to the mitral group (p < 0.01). The rate of mortality was also higher among the double valve replacement patients when compared with both the aortic (p = 0.0002) and mitral (p = 0.006) groups.     

The necessity of reoperation for patients with Bjork-Shiley, St Jude Medical, Hancock and Carpentier-Edwards prostheses

The purpose of this study was to determine the criteria of valve selection from the long-term results of Hancock, Carpentier-Edwards, St Jude Medical and Bjork-Shiley prostheses, taking into special account the frequency of reoperation. Reoperations on the Hancock bioprosthesis were performed on six patients for tissue leaflet disruption with an incidence of 2.2 per cent/patient-year. Reoperations on the Carpentier-Edwards bioprosthesis were performed on 24 patients for tissue leaflet disruption in 23 patients and prosthetic valve endocarditis (PVE) in one, with an incidence of 3.8 per cent/patient-year. Reoperations on the Bjork-Shiley prosthesis were performed in two patients for severe hemolysis, with an incidence of 0.32 per cent/patient-year. Reoperations on the St Jude Medical prosthesis were performed on 3 patients, for valve thrombosis in one patient, PVE in one, and hemolysis in one, with an incidence of 0.23 per cent/patient-year. The overall mortality rate was 20 per cent, or 7 patients, and the indications for reoperation affected this. Patients with primary tissue failure had a mortality rate of 10.3 per cent; those with a thrombosed valve, 0 per cent; those with hemolysis, 66.7 per cent; and those with valve infection, 100 per cent. A good chance of survival may be achieved in patients facing prosthetic valve complications by performing reoperation as soon as possible after early detection, since mortality is high following emergency reoperation and in patients with severe symptoms. Currently, we recommend mechanical prostheses for valve replacement except in patients over 70 years old and in younger patients with absolute contraindications to anticoagulative therapy.