Long-Term Follow-up of the Björk-Shiley Prosthetic Valve Used in the Mitral Position

This study analyzes 547 patients who had mitral valve replacement with a Björk-Shiley prosthesis over a 9-year period (mean follow-up, 46.5 months). Operative mortality was 7.3%, and 5-year survival was 76.9%. Serious anticoagulation problems occurred in 1.8% (10 patients) and serious thromboembolic episodes in 5.3% (28 patients) (1.3 per 1,000 patient-months). The study includes 257 patients with isolated mitral valve replacement (Group 1) and 290 who had associated procedures (Groups 2 through 5). Hospital mortality in Group 1 was 2.7% compared with 11.7% in Groups 2 through 5 (p < 0.01). Five-year survival for Group 1 was 83.9% and for the others, 70.5% (p < 0.01), and two-thirds of the deaths occurred in Groups 2 through 5.In the patients in Group 1 with pure mitral insufficiency (MI), 5-year survival was 70.9%, significantly lower (p < 0.05) than the 90.2% for those with pure mitral stenosis (MS) and 84.3% for those with combined stenosis and insufficiency (MI + MS). In Groups 2 through 5, 5-year survivals were 56.0% (MI), 82.5% (MS), and 71.4% (MI + MS).Significantly lower (p < 0.01) 5-year survival was found for those in Functional Class IV preoperatively compared with Class III or II. In Group 1, 89.1% were in Class II, 86.7% in Class III, and 64.8% in Class IV. The corresponding figures in the combined other groups were 72.7%, 76.4%, and 48.9%, respectively. This study shows that rhythm plays a small role in thromboembolic episodes and survival and that there is strong evidence for early operation in patients with MI.     

Heart Valve Replacement with the Hancock Bioprosthesis: A 6-Year Review

All patients who had a mitral or aortic Hancock valve replacement between June, 1974, and June, 1979, were reviewed. A total of 734 bioprostheses were implanted in 632 patients: 291 had mitral (MVR), 239 had aortic (AVR), and 102 had both mitral and aortic valve replacement (MVR + AVR). In 228 patients, an associated surgical procedure was necessary. It involved conservative valve operation in 205 of them. The hospital mortality was 9.6% (28) for MVR (11.5% with associated operation), 4.6% (11) for AVR (8.7% with associated operation), and 13.7% (14) for MVR + AVR (13.0% with associated operation).The follow-up period was between 1 and 6 years with a total follow-up of 934.6, 714.6, and 288.3 patient-years for MVR, AVR, and MVR + AVR, respectively. The late mortality was 0.96% (9), 1.53% (11), and 2.08% (6) per patient-year for MVR, AVR, and MVR + AVR, respectively. The thromboembolic rate was 1.49%, 0.14%, and 2.08% per patient-year for MVR, AVR, and MVR + AVR, respectively. There were twelve valve failures (six were due to rupture; four, thrombosis; one, insufficiency because of intrinsic failure; and one, stenosis without evident cause at reoperation). This represents a failure rate of 0.53%, 0.13%, and 2.08% per patient-year for MVR, AVR, and MVR + AVR, respectively. These results encourage us to continue our routine use of the glutaraldehyde xenografts as the safest valve substitute at present.     

Early and late risk of mitral valve replacement. A 12 year concomitant comparison of the porcine bioprosthetic and prosthetic disc mitral valves

A consecutive series of 706 mitral valve replacements was performed from January, 1972, to January, 1984. The follow-up ranged from 6 to 150 months with a mean of 50 and a median of 43 months. Seven percent (50) of the patient were lost to follow-up. There were 243 men and 463 women, whose ages ranged from 17 to 86 years (mean 58). A porcine bioprosthetic valve was implanted in 528 patients (514 Hancock and 14 Carpentier-Edwards valves) and a prosthetic disc valve in 178 patients (102 standard disc Bj?rk-Shiley, 34 Beall, and 42 Harken disc valves). Seven patients were in Functional Class II, 325 in Class III, and 374 in Class IV. A concomitant operative procedure was performed in 253 of the 706 patients (36%). Mitral regurgitation was the primary hemodynamic lesion in 363 and mitral stenosis in 343. Operative mortality figures were as follows: 77 of 706 (11%) for the overall group, 34 of 453 (7.5%) for isolated mitral valve replacement, 30 of 169 (17.5%, p = 0.001) for mitral replacement plus coronary bypass, 49 of 528 (9%) for the bioprosthetic valve group, and 28 of 178 (16%) for the prosthetic disc valve group (p = 0.01). After the operation, 262 patients were in Functional Class I, 99 in Class II, and 18 in Class III. The long-term survival rate was significantly lower in patients who had an associated procedure (45% +/- 6%), who had mitral regurgitation rather than mitral stenosis (53% +/- 5% versus 67% +/- 4%) (p = 0.002), who were in Functional Class IV rather than Classes I to III (51% +/- 4% versus 70% +/- 4%) (p = 0.001), and who received a prosthetic disc valve rather than a bioprosthesis (40% +/- 6% versus 67% +/- 4%) (p = 0.001). Thromboembolic rates were significantly higher with prosthetic valves than with bioprosthetic valves (4.6% +/- 0.22% versus 2.4% +/- 0.5% per patient-year of follow-up), and the incidence of anticoagulant-related hemorrhage was significantly higher in the prosthetic valve group (1.65% versus 0.43% per patient-year). Primary valve dysfunction was significantly more common in the bioprostheses (1.23% versus 0.40% per patient-year).(ABSTRACT TRUNCATED AT 400 WORDS)     

Valvuloplasty for rheumatic mitral valve disease. A surgical challenge

From January 1981 through February 1985, 241 patients with rheumatic mitral valve disease (mean age 21.5 +/- 11.8 years) were subjected to comprehensive mitral valvuloplasty. One hundred seven patients (44.4%) were 15 years or younger and 63 (26.1%) were 12 years or younger. One hundred seventy five patients had pure or predominant regurgitation (mean age 19.3 +/- 10.7 years) and 40 (16.6%) had active rheumatic carditis at the time of the operation. Almost all patients (229) were in New York Heart Association Functional Class III or IV. The techniques used included shortening of anterior leaflet chordae tendineae (136 patients), resection of secondary, tertiary, and basal posterior leaflet chordae (156 patients), commissurotomy (113 patients), and implantation of a Carpentier ring (164 patients). Current operative mortality is 1.9%. The survivors were followed up for 576 patient-years (mean 2.64 +/- 1.32 years). Late mortality was 2.60% per patient-year and was valve related in 1.04% per patient-year. Reoperation was required in 25 patients (4.34% per patient-year), mostly (72%) in the first year. There were only two cases (0.35% per patient-year) of thromboembolism and three cases (0.52% per patient-year) of infective endocarditis. Hence valve failure occurred at a linearized rate of 6.08% per patient-year but was fatal in only 22% of the patients. There was no relationship between valve failure and the type of lesion or procedure performed, but reoperation was required more frequently in patients aged 12 years or less (7.33% per patient-year) than in those older than 12 years (3.29% per patient-year) (p less than 0.05). Actuarial survival rate at 41/2 years was 90%, and 82% of the patients were free from valve-related complications. Valve function after valvuloplasty was assessed clinically. Eighty-four percent of the patients had a good immediate result, but this figure dropped to 69% at the end of the follow-up period (p less than 0.05). The remainder had moderate valve dysfunction. However, 85% of the patients remain in New York Heart Association Functional Class I. Mitral valvuloplasty is an excellent alternative to valve replacement in young patients with rheumatic mitral valve disease. Persistent or reactivated rheumatic carditis may be a significant factor of valve failure, and penicillin prophylaxis is mandatory after operation.     

Determinants of Operative Survival Following Combined Mitral Valve Replacement and Coronary Revascularization

To determine the operative survival rate following combined mitral valve replacement (MVR) and coronary artery bypass graft (CABG) operation, we evaluated 100 patients, who were seen consecutively at the Peter Bent Brigham and Brigham and Women's Hospital from 1972 to 1981. There were 63 men and 37 women; the mean age was 62 years. Thirty-six patients were in New York Heart Association (NYHA) Functional Class III, and 64 were in Functional Class IV. Mitral regurgitation was predominant in 76 patients; mitral stenosis, in 24. Emergency operations were performed in 15 patients, and elective or semielective operations were performed in 85.There were 18 operative deaths (18%): 9 in patients having elective operations (10.5%) and 9 in those having emergency operations (60%; p < 0.01). Significant preoperative factors related to operative death were NYHA functional class, increased pulmonary vascular resistance, lower cardiac index, and lower ejection fraction in the nonsurvivors. The rate of survival did not differ according to sex, age, or degree of coronary artery disease. In addition, myocardial protection with potassium cardioplegia and complete coronary revascularization significantly reduced operative mortality in the elective group of patients but did not alter the mortality in the emergency group.     

A 25-Year Experience with the Closed Method of Treatment in 139 Patients with Mitral Stenosis

A 25-year experience with 139 patients undergoing closed mitral commissurotomy is reviewed. The primary indication for closed mitral commissurotomy was mitral stenosis, but 24 patients also had other less important valvular defects. Preoperatively, all patients were in New York Heart Association (NYHA) Functional Class III or IV. Average age was 46 years (range, 18 to 77 years). There were 24 men and 115 women. No further operation after initial closed mitral commissurotomy was required in 68% of the patients (95 patients), and NYHA Functional Classification was improved in 93%. Postoperative complications occurred in 3%, and operative mortality was 2.0%. Follow-up revealed restenosis in 6% of the patients, mitral regurgitation in 14%, complications in 7%, and late deaths in 3%. Reoperation, required in 32% (44 of 139 patients), included a second closed mitral commissurotomy (21 patients), open mitral commissurotomy (3), mitral valve replacement (MVR) (18), and MVR after a second closed mitral commissurotomy (2). Improvement in NYHA classification was found in 82% of these patients. Operative mortality was 9.5% for patients having a second closed mitral commissurotomy and 20% for those having MVR.     

Twenty years' experience with the Model 6120 Starr-Edwards valve in the mitral position

A total of 549 nonconsecutive patients underwent isolated mitral valve replacement with a Starr-Edwards valve prosthesis (Model 6120) at the University of Louvain (Belgium) from 1965 to 1985. Ninety-seven percent of the patients could be traced and only 17 patients were lost to follow-up. Cumulative follow-up totalled 3,130 patient-years. Actuarial and linearized statistical techniques were used to describe the survival and the incidence of valve-related complications (according to stringent criteria). Long-term overall survival rate including early deaths was 79% +/- 0.02% at 5 years, 65% +/- 0.03% at 10 years, and 54% +/- 0.04% at 19 years, with a linearized incidence of late deaths of 3.9% +/- 0.5% per patient-year. The incidence of late valve-related deaths was 1.25% per patient-year. Valve-related complications occurred at the following rates: thromboembolism 3.1% per patient-year, anticoagulant-related hemorrhage 1.08% per patient-year, endocarditis 0.26% per patient-year, reoperation and periprosthetic leak 0.45% per patient-year, and structural failure 0% per patient-year. All valve-related mortality and morbidity were calculated at 4.9% per patient-year and the rate of valve failure (deaths and reoperations) at 1.4% per patient-year. Among 376 survivors, 352 clinical functions could be obtained: 95% of patients belong to Class I or II of the New York Heart Association after operation versus 24% before operation. The study shows the structural durability of the Starr-Edwards mitral valve with a follow-up over 20 years. The Model 6120 valve may be considered a faithful standard.     

Mechanical valve replacement in children and teenagers

A previous study from this unit showed that only 19% of children with mitral bioprostheses were free from complications after 7 years and prompted us to review the performance of new-generation mechanical prostheses implanted in the same population group. In a 5-year period (1980-1985), 352 patients 20 years old and younger (mean age 15.3 +/- 4 years) with rheumatic valvular disease had 177 mitral, 62 aortic and 113 double (mitral + aortic) valve replacements with Medtronic-Hall or St. Jude prostheses. The overall early mortality was 6.3%. All survivors, followed up for a total of 1171 patient-years, received oral anticoagulation. The late mortality for mitral, aortic and double valve replacement was 4.1% per patient-year, 4.3% per patient-year and 8.0% per patient-year, respectively (P less than 0.05), and was valve-related in 46% of the cases. Twenty-nine patients, all but 2 in the mitral and double valve replacement groups, were reoperated upon (2.5% per patient-year), mainly for infective endocarditis (34%), for prosthetic thrombosis (33%) and for bland periprosthetic leak (31%). The incidence of thrombotic obstruction was 1.1% per patient-year: mitral valve replacement, 1.0% per patient-year; aortic valve replacement 0.5% per patient-year; and double valve replacement, 1.7% per patient-year; P less than 0.05) and was fatal in 33% of the cases. Major systemic thromboembolism occurred at the rate of 1.4% per patient-year, similar in the three groups. The incidence of prosthetic endocarditis was 0.9% per patient-year.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mitral valve replacement: a nine-year follow-up of risks and survivals.

Experience with mitral valve replacement over a nine-year period is reviewed. Hospital mortality was 8.9%, with an additional late mortality of 18.5% during a mean follow-up period of 4.34 years. Study of the factors influencing the results of valve replacement revealed a direct correlation between long-term survival and New York Heart Association (NYHA) Functional Class, as judged preoperatively, as well as left ventricular end-diastolic pressure, cardiac index, type of valve lesion, and presence of associated coronary artery disease. Hospital mortality was 32% (p less than 0.01) for those patients in NYHA Functional Class IV before operation, compared with 3% for Class III patients. Untreated concomitant coronary artery disease was associated with a significantly higher perioperative mortality of 28% (p = 0.002) compared with an 8% mortality in patients with coronary artery disease treated by vein bypass at the time of mitral valve replacement. Patients with normal coronary arteries documented angiographically before operation had a 1% hospital mortality. Seventy-two percent of all patients are still alive at a maximum follow-up of nine years. Eighty-three percent of those survivors who were in Functional Class III or IV before operation are now considered to be in Class I or II. We conclude that patients should undergo mitral valve replacement before the development of the advanced functional stage of valve disease. In addition, coronary arteriograms should be performed on all patients who are more than 40 years old at the time of cardiac catheterization, and revascularization considered at the time of mitral valve replacement for those patients with significant coronary disease.     

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.     

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.     

Isolated mitral valve replacement with the Hancock bioprosthesis: a 13-year appraisal

Four hundred seventy-six patients underwent isolated mitral valve replacement (MVR) with the glutaraldehyde-preserved porcine Hancock bioprosthesis from March, 1970, through December, 1981. There were 312 female and 164 male patients ranging in age at operation from 9 to 68 years (average, 53 years). Associated surgical procedures were performed in 35 patients. Hospital mortality was 13%, the main cause of death being low-output syndrome. The survivors were followed from 1.6 to 13.2 years (mean, 5.2 years). Cumulative duration of follow-up is 2,180 patient-years and is 97% complete. Overall late mortality is 3.1 +/- 0.3% per patient-year, and actuarial survival is 73.8 +/- 3.4% at 13 years. Embolic accidents occurred in 45 patients and were fatal in 13; the linearized incidence of postoperative systemic thromboemboli is 2.1 +/- 0.3% per patient-year. Reoperation was necessary in 49 patients: in 4 because of valve endocarditis, with 3 deaths; in 6 because of perivalvular leak, with no deaths; in 2 because of left atrial thrombosis; and in 37 because of valve dysfunction due to primary tissue failure, caused mainly by calcific degeneration of the tissue, with 5 operative deaths. Actuarial freedom from primary tissue failure is 58 +/- 6.6% at 13 years. Extended follow-up after MVR with the Hancock bioprosthesis confirms the satisfactory performance and low thrombogenicity of this device up to 13 years after operation.(ABSTRACT TRUNCATED AT 250 WORDS)     

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)     

Clinical Experience with the Smeloff-Cutter Prosthesis: 1- to 12-Year Follow-up

To determine the long-term results of aortic valve replacement with the Smeloff-Cutter prosthesis, the fate of 358 of 459 (78%) consecutive patients was determined 1 to 12 years postoperatively. There were 319 male patients (70%). Mean age at operation was 57 years (range, 15 to 84 years). Aortic stenosis was the dominant lesion in 267 patients (58%) and aortic regurgitation in 133 patients (29%). Fifty-nine patients (13%) had both aortic stenosis and regurgitation. In addition to aortic valve replacement, 93 patients (20%) had coronary artery bypass, 30 (6.5%) had mitral commissurotomy, 23 (5%) had mitral valve replacement, and 41 (9%) had other procedures. Preoperative status by New York Heart Association Functional Class was: Class I, 3 (1%); Class II, 39 (8%); Class III, 148 (32%); and Class IV, 269 (59%). Operative (30-day) mortality was 8.5% (39 out of 459).Functional improvement was obtained in all postoperative survivors: 345 (82%), Class I; 63 (15%), Class II; and 12 (3%), Class III. A perivalvular leak developed in 6 patients (1%) and subacute bacterial endocarditis in five (1%). Actuarial long-term survival was 80% at 5 years and 71% at 8 years. Thromboembolism occurred in 34 patients (9.5%). The incidence of thromboembolism per 100 patient-years for patients receiving no anticoagulants was 5.4; antiplatelet agents, 2.9; and Coumadin (sodium warfarin), 2.6. Major thromboembolism was uncommon in patients on a regimen of sodium warfarin but major morbidity from bleeding was significant.     

Functional rehabilitation after cardiac valve surgery

Functional rehabilitation after cardiac valve surgery was evaluated in a series of 267 patients operated upon during the years 1963 through 1970. All but a few were in N.Y.H.A. Functional Class III or IV prior to operation. Hospital mortality was 14%, and the late mortality was 26%. During the last four years (1967–1970), when only current-model Starr-Edwards valves were used, hospital mortality was reduced to 8% (5.4% for single- or double-valve replacement), but late mortality (15% within two years) was unchanged. The reduction in hospital mortality was due to improvements in surgical technique and postoperative care rather than to improved valve design.Although more than 70% of the survivors were in Functional Class I or II postoperatively, fewer than 20% returned to work and only 24% were asymptomatic. These findings did not improve during 1967–1970. Multivariable computer analysis failed to reveal specific preoperative factors that correlated with late mortality or functional results. Isolated mitral stenosis was associated with the lowest late mortality, and isolated mitral regurgitation had the highest late mortality. Long-standing congestive heart failure also carried a poor prognosis. Complications related to the prosthetic valve were reduced with current-model prostheses, but valve-related causes accounted for less than 12% of deaths, and late mortality due to progressive cardiac disease was unchanged. It is suggested that correction of cardiac valve lesions is performed too late in the course of the disease to significantly influence rehabilitation of most 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.     

Long-Term Results of Cardiac Valve Replacement with the Delrin-Disc Model of the Björk-Shiley Valve Prosthesis

One hundred two Björk-Shiley valve prostheses with the Delrin-disc occluder were implanted in 83 patients between January, 1971, and July, 1972. Fifty-eight were in the mitral position, 42 in the aortic, and 2 in the tricuspid. Complete follow-up until 1981 was obtained in 93% of the patients (mean follow-up, 66.8 months). Hospital mortality was 18% and late mortality, 19%. Survival according to actuarial methods was 84.8% at 5 years and 78.1% at 9 years after operation. Thromboembolism was detected in 8.8% of patients but caused no deaths. The incidence was 1.2% and 1.5% per year in those patients treated with Coumadin and antiplatelet agents, respectively. Reoperation was necessary in 13% of the patients.Most survivors (72%) are in New York Heart Association Functional Class I, despite a preoperative status of Class III or IV in 57% of the patients. Hospital mortality may be due to poorer understanding of patient management and less refined techniques of myocardial protection. Long-term survival with this prosthesis is similar to that in more recent studies, and rates of thromboembolism and malfunction compare favorably with other prosthetic valves.     

Long-term durability of the Hancock porcine bioprosthesis following combined mitral and aortic valve replacement: an 11-year experience

Long-term evaluation of patients undergoing combined mitral and aortic valve replacement (MVR + AVR) with a porcine bioprosthesis provides the opportunity for a direct comparison of the durability of the mitral versus the aortic porcine bioprosthesis in the same patient. From 1970 to 1983, 71 patients underwent MVR + AVR with Hancock porcine bioprostheses. There were 46 men an 25 women ranging in age from 21 to 64 years (mean, 47.5 +/- 5 years). Sixteen patients (22.5%) died at operation. The survivors were followed from 0.2 to 11.5 years (mean, 5.7 +/- 3 years). Duration of follow-up was 313 patient-years and was 100% complete. Overall late mortality was 6.7 +/- 1.4% per patient-year (linearized incidence), and actuarial survival was 54.2 +/- 8% at 11 years. Endocarditis occurred in 4 patients (linearized incidence of 1.3 +/- 0.6% per patient-year); thromboembolic events were sustained by 4 patients (linearized incidence of 1.3 +/- 0.6% per patient-year); the event was fatal in 1 patient. Actuarial freedom from thromboembolism was 90 +/- 4.8% at 11 years. Reoperation for primary tissue failure was performed in 11 patients (linearized incidence of 3.5 +/- 1% per patient-year) with no deaths; in 7 patients both bioprostheses were explanted, and in 4, only the mitral bioprosthesis was replaced. The durability of explanted aortic and mitral porcine bioprostheses was not significantly different, and the evaluation of seven pairs of explanted aortic and mitral bioprostheses showed similar amounts of calcification. Actuarial freedom from reoperation because of primary tissue failure was 44.6 +/- 13.7% at 11 years.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

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.