ECHOCARDIOGRAPHY ASSESSMENT OF THE HALL KASTER MITRAL PROSTHESIS

To study the effect of the Hall Kaster prosthesis on left ventricular filling characteristics after mitral valve replacement, postoperative M-mode echocardiograms of the left ventricle from sixteen patients were digitized to determine the peak rate of dimension (D) Increase of the left ventricle during diastole (peak dD/df) and the rapid filling period (RFP). These were compared with fourteen normal controls, thirty patients with Starr Edwards and thirty patients with Bjork Shiley mitral prosthesis. Results suggest that the Hall Kaster mitral prosthesis is less obstructive than either the Starr Edwards or the Bjork Shiley prosthesis, and tends to approximate the normal mitral valve.     

Heart valve replacement with the Sorin tilting-disc prosthesis. A 10-year experience.

From 1978 to 1988, 697 patients with a mean age of 48 +/- 11 years (range 5 to 75 years) received a Sorin tilting-disc prosthesis; 358 had had aortic valve replacement, 247 mitral valve replacement, and 92 mitral and aortic valve replacement. Operative mortality rates were 7.8%, 11.3%, and 10.8%, respectively, in the three groups. Cumulative duration of follow-up is 1650 patient-years for aortic valve replacement (maximum follow-up 11.4 years), 963 patient-years for mitral valve replacement (maximum follow-up 9.9 years) and 328 patient-years for mitral and aortic valve replacement (maximum follow-up 9.4 years). Actuarial survival at 9 years is 72% +/- 4% after mitral valve replacement, 70% +/- 3% after aortic valve replacement, and 50% +/- 12% after mitral and aortic valve replacement, and actuarial freedom from valve-related deaths is 97% +/- 2% after mitral valve replacement, 92% +/- 2% after aortic valve replacement, and 62% +/- 15% after mitral and aortic valve replacement. Thromboembolic events occurred in 21 patients with aortic valve replacement (1.3% +/- 0.2%/pt-yr), in 12 with mitral valve replacement (1.2% +/- 0.3% pt-yr), and in seven with mitral and aortic valve replacement (2.1% +/- 0.8%), with one case of prosthetic thrombosis in each group; actuarial freedom from thromboembolism at 9 years is 92% +/- 3% after mitral valve replacement, 91% +/- 3% after aortic valve replacement, and 74% +/- 16% after mitral and aortic valve replacement. Anticoagulant-related hemorrhage was observed in 15 patients after aortic valve replacement (0.9% +/- 0.2%/pt-yr), in 9 after mitral valve replacement (0.9% +/- 0.3%/pt-yr), and in 6 with mitral and aortic valve replacement (0.9% +/- 0.5%/pt-yr); actuarial freedom from this complication at 9 years is 94% +/- 2% after aortic valve replacement, 91% +/- 4% after mitral valve replacement, and 68% +/- 16% after mitral and aortic valve replacement. Actuarial freedom from reoperation at 9 years is 97% +/- 2% after mitral and aortic valve replacement, 92% +/- 4% after mitral valve replacement, and 89% +/- 3% after aortic valve replacement, with no cases of mechanical fracture. The Sorin valve has shown a satisfactory long-term overall performance, comparable with other mechanical prostheses, and an excellent durability that renders it a reliable heart valve substitute for the mitral and aortic positions.     

Incidence of primary tissue valve failure in porcine bioprosthetic heart valves

This report provides retrospective follow-up data on 324 consecutive patients who received a Hancock-I porcine valve in the aortic or the mitral position, or in both positions, between June, 1974, and December, 1976. This analysis included 319 valves (193 mitral, 126 aortic) available for study of the incidence of primary tissue valve failure after 10 to 12.5 years of follow-up. Of the 319 prostheses at risk, 114 instances of primary tissue valve failure occurred. Seventy-three of the failed valves were in the mitral position, and 41 were in the aortic position. The calculated actuarial probability of freedom from primary tissue valve failure was 52 +/- 5% for the mitral and 58 +/- 6% for the aortic prostheses at 12.5 years of follow-up. For patients older than 40 years at the time of operation, the rate of freedom from primary failure was 68 +/- 8% and 55 +/- 6% for aortic and mitral prostheses, respectively, at 12.5 years. Comparison of both actuarial curves disclosed no meaningful difference. However, a tendency toward greater failure rate was observed in the mitral prosthesis group.     

The Monostrut Bj?rk-Shiley valve. Seven years' experience.

The results of cardiac valve replacement with the Monostrut Bj?rk-Shiley prosthesis (Shiley, Inc., Irvine, Calif.) during a 7-year period are presented. A total of 984 valves were implanted in 820 patients from May 1983 to April 1990. Aortic valve replacement was performed in 378 patients, mitral replacement in 294, and multiple replacement in 148. In addition, 180 patients (22%) underwent associated procedures. Mean age was 52.6 +/- 11 years. Operative (30 days) mortality was 5.9% (49 patients): 3.9% (15 patients) for aortic, 7.8% (23 patients) for mitral, and 7.4% (11 patients) for multiple valve replacement. All patients were given long-term anticoagulation therapy. Follow-up was 99% complete (eight patients were lost to follow-up), with a closing interval of 3 months, and totaled 2422 patient-years. Valve-related complications, expressed as percentage event-free (+/- standard error) at seven years were as follows: structural deterioration, 100%; nonstructural dysfunction, 98.3% +/- 0.6%; thromboembolism, 90.2% +/- 1.7%; anticoagulant-related hemorrhage, 88.7% +/- 2.8%; and prosthetic valve endocarditis, 98.1% +/- 0.8%. There were no cases of valve thrombosis. Actuarial survival (free from operative, valve-related, and sudden death) was 88.4% +/- 1.2% at 7 years. Freedom from reoperation was 96.8% +/- 0.1%. Probability of being free from all valve-related morbidity and mortality was 70% +/- 3%, and 708 (93%) of the survivors were in New York Heart Association class I or II. Serial Doppler echocardiograms were done prospectively in 243 patients (with 154 aortic and 120 mitral prostheses), both postoperatively and at regular intervals up to 3 years. Mean prosthetic gradients ranged from an average of 20.9 to 7 mm Hg in the aortic prostheses (21 to 29 mm) and from 6.1 to 4.8 mm Hg in the mitral prostheses (25 to 31 mm). The gradients in each patient did not change significantly during the follow-up period. Our 7 year's experience with the Monostrut valve shows a low rate of valve-related complications, a durable design, and good hemodynamic and functional results.     

25-year experience with 456 combined mitral and aortic valve replacement for rheumatic heart disease

BACKGROUND: Valvular heart disease in developing countries resulting from rheumatic fever is disabling and if untreated leads to congestive heart failure and death. Valve replacement has remained the procedure of choice for advanced valve disease. METHODS: Between 1973 and 1997, 456 patients underwent combined mitral and aortic valve replacement. In light of our favorable earlier experience the Starr-Edwards ball valve prostheses were implanted in 90% and 72.8% of mitral and aortic positions, respectively. Follow-up ranged from 1 to 24 years with a median of 8.5 years. RESULTS: The 30-day hospital death rate was 9.2% and late death occurred in 10.1%. A low-intensity anticoagulant regimen was followed to maintain the target prothrombin time at 1.5 times the control value. The actuarial survival at 5, 10, 20, and 24 years was 90.4%, 85.6%, 84.4%, and 82.4% per year, respectively. CONCLUSIONS: In view of the acknowledged advantage of superior durability, increased thromboresistance in our patient population, and its cost effectiveness the Starr-Edwards ball valve is the mechanical prosthesis of choice for advanced combined valvular disease. The low-intensity anticoagulant regimen has offered sufficient protection against thromboembolism as well as hemorrhage.     

Mitral valve replacement in patients younger than 6 years of age.

We present our experience in mitral valve replacement (including left-sided tricuspid valve in corrected transposition) in patients younger than 6 years of age. The long term results were examined with special focus on re-replacement of the valve. Between 1974 and 1995, we performed mitral valve replacement in 14 patients younger than 6 years of age, with no operative mortality. There were 3 late deaths, caused by endocarditis, valve thrombosis, and congestive heart failure, respectively. The five-year-survival rate after primary replacement was 85%, and the ten-year-survival rate was 75%, using Kaplan-Meier analysis. Ten patients (11 occasions) required repeated mitral valve replacements at 2 months to 17 years after the original replacement. The indication for the second or third mitral valve replacement was paravalvular leakage (2 patients), valve thrombosis (1 patient), degeneration in the porcine prosthesis (3 patients), and patient outgrowth of the original small prosthesis (5 patients). Again there was no operative mortality. One patient who suffered from multiple occasions of valve thrombosis died at two years after the second replacement. All patients who had outgrown the prosthetic valve received larger prosthesis at the second replacement than at the primary replacement. The actuarial percentage of freedom from valve-related events at 3 years, 5 years, and at 10 years, was 50%, 37%, and 8%, respectively. CONCLUSIONS: Mitral valve replacement in patients younger than 6 years of age can be performed relatively safely, but meticulous follow-up and appropriate decision making for re-replacement is mandatory for the long-term survival of these patients.     

Mitral valve replacement in patients younger than 6 years of age

We present our experience in mitral valve replacement (including left-sided tricuspid valve in corrected transposition) in patients younger than 6 years of age. The long term results were examined with special focus on re-replacement of the valve. Between 1974 and 1995, we performed mitral valve replacement in 14 patients younger than 6 years of age, with no operative mortality. There were 3 late deaths, caused by endocarditis, valve thrombosis, and congestive heart failure, respectively. The five-year-survival rate after primary replacement was 85%, and the ten-year-survival rate was 75%, using Kaplan-Meier analysis. Ten patients (11 occasions) required repeated mitral valve replacements at 2 months to 17 years after the original replacement. The indication for the second or third mitral valve replacement was paravalvular leakage (2 patients), valve thrombosis (1 patient), degeneration in the porcine prosthesis (3 patients), and patient outgrowth of the original small prosthesis (5 patients). Again there was no operative mortality. One patient who suffered from multiple occasions of valve thrombosis died at two years after the second replacement. All patients who had outgrown the prosthetic valve received larger prosthesis at the second replacement than at the primary replacement. The actuarial percentage of freedom from valve-related events at 3 years, 5 years, and at 10 years, was 50%, 37%, and 8%, respectively. Conclusions: Mitral valve replacement in patients younger than 6 years of age can be performed relatively safely, but meticulous follow-up and appropriate decision making for re-replacement is mandatory for the long-term survival of these patients.     

The Ionescu-Shiley pericardial valve: results in 473 patients

From January 1, 1980, through December 31, 1985, 473 patients underwent valve replacement with an Ionescu-Shiley valve. Overall hospital mortality was 7.8%. Major associated procedures and preoperative New York Heart Association (NYHA) Classes IV and V influenced hospital mortality significantly. The mean follow-up was 2.6 +/- 1.3 years. Late mortality was 5.9%. Overall actuarial survival was 81% at 5 years. A chief cause of reoperation was cusp rupture of a mitral prosthesis in 5 patients (all after aortic and mitral valve replacement). The overall actuarial reoperation-free incidence was 93% at 5 years. Thromboembolic (TB) phenomena occurred at a linear incidence of 1.4 +/- 0.3% per patient-year or an actuarial thromboembolism-free incidence of 92% at 5 years. Univariate and multivariate analyses showed that postoperative NYHA Class, rhythm at follow-up, and anticoagulant therapy significantly influenced the incidence of TE phenomena.     

Influence of type of prosthesis on late results after combined mitral-aortic valve replacement

The influence of type of prosthesis on the late outcome of patients with combined mitral-aortic valve replacement was analyzed by comparing, at a 14-year follow-up, patients receiving two biological prostheses (group 1; n = 135), two mechanical prostheses (group 2; n = 221), or a mechanical prosthesis in the aortic position and a bioprosthesis in the mitral position (group 3; n = 97). No difference was found among the three groups in terms of actuarial survival and incidence of and freedom from valve-related deaths, thromboemboli, and hemorrhages. Patients with biological prostheses had a significantly greater incidence of structural valve deterioration, reoperations, and overall complications when compared with patients with only mechanical prostheses. The results of an extended follow-up of patients with combined mitral-aortic valve replacement indicate that mechanical prostheses perform better in the long-term owing to their superior durability when compared with biological valves. The use of bioprostheses should be confined to old patients with limited life expectancy because of their cardiac disease, provided that anticoagulants are not used. Combination of mechanical and biological prostheses in the same patient should be avoided because the advantages of each type of prosthesis are lost.     

Fourteen years' experience with the Bj?rk-Shiley tilting disc prosthesis

Between 1970 and 1984, 1,574 Bj?rk-Shiley valve prostheses have been implanted in 1,171 patients in Glasgow. Between 1970 and 1980, 1,023 standard disc prostheses were implanted in 729 patients: 184 had aortic valve replacement, 323 mitral, and 222 multiple valve replacement. Between 1980 and 1984, 551 convexo-concave valves were implanted in 442 patients: 125 had aortic, 228 mitral, and 89 multiple valve replacement. Concomitant coronary artery bypass grafting was performed in 9.2% of the latter group as compared with 2.7% of the earlier group. The overall hospital (30 day) mortality for the group with the standard disc prosthesis was 10.4% and for patients with the convexo-concave prosthesis, 7.0%. Cumulative follow-up extends to 4,125 patient-years--standard disc group 3,378 patients-years, range 4 to 14 years (mean 5.2 years); convexo-concave group 747 patient-years, range 1.5 to 5.3 years (mean 1.9 years). The late mortality is 3.8% per patient-year--standard disc group 2.9% per patient-year and convexo-concave group 4.3% per patient year (no significant difference). Actuarial survival rate at 12 years for the whole group, excluding operative deaths, is 69.4% +/- 6.3%. The freedom from all valve-related complications at 12 years is 65.9% +/- 6.5%. there is no significant difference in the incidence of most major complications between the standard disc and convexo-concave prostheses apart from the occurrence of mitral valve thrombosis (p less than 0.05) in the standard disc group and outlet strut fracture (p less than 0.005) in the convexo-concave group. These results confirm the excellent long-term performance of the Bj?rk-Shiley tilting disc prosthesis.     

Structural valve deterioration in mitral replacement surgery: comparison of Carpentier-Edwards supra-annular porcine and perimount pericardial bioprostheses.

BACKGROUND: Bioprostheses preserved with glutaraldehyde, both porcine and pericardial, have been available as second-generation prostheses for valve replacement surgery. The performance with regard to structural valve deterioration with the Carpentier-Edwards supra-annular (CE-SAV) porcine bioprosthesis and the Carpentier-Edwards Perimount (CE-P) pericardial bioprosthesis (Baxter Healthcare Corp, Edwards Division, Santa Ana, Calif) was evaluated to determine whether there was a difference in mitral valve replacement. METHODS: The CE-SAV bioprosthesis was implanted in 1266 overall mitral valve replacements (isolated mitral, 1066; mitral in multiple, 200) and the CE-P bioprosthesis in 429 overall mitral valve replacements (isolated mitral, 328; mitral in multiple, 101). The mean age of the CE-SAV population was 64.2 +/- 12.2 years and that of the CE-P population, 60.7 +/- 11.7 years (P =.0001). For the study, structural valve deterioration was diagnosed at reoperation for explantation. RESULTS: The freedom from structural valve deterioration was evaluated to 10 years, and the freedom rates reported are at 10 years. For the overall mitral valve replacement groups, the actuarial freedom from deterioration was significant (P =.0001): CE-P > CE-SAV for 40 years or younger, 80% versus 60%; 41 to 50 years, 91% versus 61%; 51 to 60 years, 84% versus 69%; 61 to 70 years, 95% versus 75%. The older than 70-year group was 100% versus 92% (no significant difference). The actual freedom from structural valve deterioration also demonstrated the same pattern at 10 years: 40 years or younger, CE-P 82% versus CE-SAV 68%; 41 to 50 years, 92% versus 70%; 51 to 60 years, 90% versus 80%; 61 to 70 years, 97% versus 88%; and older than 70 years, 100% versus 97%. The independent risk factors of structural valve deterioration for the overall mitral valve replacement group were age and age groups and prosthesis type (CE-SAV > CE-P). The prosthesis type either in isolated replacement or in multiple replacement was not predictive of structural valve deterioration. The pathology of structural valve deterioration was different: 70% of CE-P failures were due to calcification and 57% of CE-SAV failures were due to combined calcification and leaflet tear. CONCLUSION: The actuarial and actual freedom from structural valve deterioration, diagnosed at reoperation, is greater at 10 years for CE-P than for CE-SAV bioprostheses. The mode of failure is different, and the cause remains obscure. Long-term evaluation is recommended, because the different modes of failure may alter the clinical performance by 15 and 20 years.     

A successful surgical treatment of mitral stenosis of double mitral valve combined with aortic regurgitation

The purpose of this paper was to present a successful double mitral commissurotomy concomitant with aortic valve replacement for 45-year-old female who was found to have rheumatic fever in her history. Double mitral valve was incidentally diagnosed by means of preoperative echocardiography. Both orifice areas were almost same and measured as 0.70 and 0.71 cm2 in size. Double mitral commissurotomy was successful to obtain optimal areas of mitral valve at surgery and aortic valve replacement was carried out with #23 Bj?rk Shiley prosthesis. Her postoperative course was uneventful and followed up one year after operation at present. This is the first case in the literature of successful surgical treatment of double mitral commissurotomy combined with aortic valve replacement.     

Forty-year durability of a Smeloff-Cutter ball valve prosthesis in the mitral position

A rare case requiring replacement of an intact Smeloff-Cutter ball prosthesis in the mitral position 40 years after implantation is presented. The Smeloff-Cutter ball valve prosthesis was designed to have two open cages. It has two potential advantages: a relatively large, effective orifice area and its self-washing effect that prevents thrombus formation. There have been only a few reports of survivors with ball valve prostheses in place for more than three decades especially in the mitral position. This is a valuable report describing the long-term durability of a Smeloff-Cutter ball valve prosthesis in the mitral position.     

A comparison of repair and replacement for mitral stenosis with partially calcified valve

From January 1978 to December 1987 we operated on 135 patients with calcified mitral stenosis. In 60 patients a conservative operation was performed (group I). Nine patients required mitral annuloplasty associated with the commissurotomy. The other 75 patients underwent mitral valve replacement (group II). In 37 patients a mechanical prosthesis was used and in 38 a biologic one. The patients given mitral valve replacement had a more heavily calcified valve than those undergoing a conservative procedure. Twenty-one patients (12 from group I and 13 from group II) required associated tricuspid annuloplasty. The mean follow-up time was 69.1 months (1 months to 10 years). There were no significant differences between the two groups in terms of operative death (0% and 4%, respectively), postoperative functional class, actuarial survival rate at 10 years (84% and 96%, respectively), and probability of freedom from thromboemboli at 10 years (98% and 96%, respectively). However, the probability of freedom from reoperation at 10 years significantly favored the conservative surgery group (84% and 69%, respectively, p less than 0.01). Finally, the probability of freedom from complications at 10 years was also significantly higher in the conservative surgery group (82% and 64%, respectively, p less than 0.005). Because of these results we believe that conservative surgery is, at present, a better alternative than mitral valve replacement for patients with partially calcified mitral stenosis.     

Comparative analysis of long-term results with porcine-aortic, bovine pericardial and tilting disc valves

The three series with the first-generation valve prostheses were reviewed for long-term clinical evaluation in isolated aortic and mitral valve replacement. Hancock porcine xenograft was implanted in 71 patients from 1977 to 1979, ionescu-Shiley pericardial xenograft (standard model) in 271 patients from 1979 to 1983, and Bjork-Shiley tilting disc valve in 194 from 1978 to 1986. In aortic position, no any significant difference among three valve types could be demonstrated in the actuarial survival and freedom from thromboembolism and valve infection, while the actuarial freedom from valve dysfunction in lonescu-Shiley valve was significantly lower than that in other two valves. Bj?rk-Shiley valve in mitral position showed satisfactory clinical performance in terms of valve-related complications and survival in comparison with two types of bioprosthetic valves. In our conclusion at present time, Bj?rk-Shiley valve is suitable for the first choice of both aortic and mitral valve prostheses. In case of valve replacement with a bioprosthesis, however, porcine aortic valve is a better choice for aortic, and bovine pericardial valve likely for mitral replacement.     

Late outcome of patients with Braunwald-Cutter mitral valve replacement

Eighty patients who underwent mitral valve replacement (MVR) with Braunwald-Cutter prostheses (54, single valve replacement; 26, multiple valve replacement) between December, 1972, and September, 1975, are discussed. The period of follow-up ranged from 72 to 120 months with a mean of 84.6 months. For the hospital survivors, actuarial survival at ten years was 73 +/- 6.7% for patients with MVR alone and 30 +/- 17.5% for those with multiple valve replacement. The linearized rate of embolic complications in patients with MVR was 3.2% per year and in patients with multiple valve replacement, 1.5% per year. These low rates of embolism allow a favorable comparison of the Braunwald-Cutter valve with other mechanical prostheses. There was no evidence of serious poppet wear or poppet escape after ten years of the valve in the mitral and tricuspid positions. Thus, elective replacement of the Braunwald-Cutter valve from the atrioventricular position because of this potential problem is not considered necessary. In the aortic position, escape of the poppet from the valve has occurred as late as 101 months. The overall morbidity for the group was high. Only 34% of the patients having MVR and 12% of those with multiple valve replacement are expected to be alive and to remain free from any major complication ten years after operation.     

Medium-Term Follow-up of the Ionescu-Shiley Heterograft Valve

Utilizing a questionnaire specifically designed to uncover potential thromboembolic episodes, we personally interviewed 97 patients who underwent valve replacement with the Ionescu-Shiley valve between January, 1977, and June, 1980. In both the aortic and mitral positions, the attrition rate after the first year was low; cumulative survival at 3 to 4 years was 78% (aortic) and 61% (mitral). None of the deaths were attributed to primary valve failure.Patients with aortic prostheses, none of whom were anticoagulated, had a cumulative thromboembolism-free rate of 94% at 3 to 4 years. Patients with mitral prostheses had a thromboembolism-free rate of 71% at 3 to 4 years, with 80% of the episodes occurring in patients in atrial fibrillation. Most emboli produced only transient symptoms, and only 1 patient has residual impairment.The Ionescu-Shiley valve performs well in the early years after valve replacement. Anticoagulation should be strongly considered for patients with mitral prostheses who are in atrial fibrillation.     

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.     

Ten years experience with the St. Jude Medical valve prosthesis for mitral valve replacement

During the 10-year period between 1980 and December 1989, isolated mitral valve replacement (MVR) with the St. Jude Medical (SJM) valve prosthesis was performed on 404 patients at our hospital, and a long-term postoperative follow-up was conducted. There were 161 males and 243 females ranged in age from 1 year to 73 years. Early operative mortality was 5.2%. Follow-up period for 383 patients who discharged from the hospital was 1970.7 patient-years. Twenty of these patients died during the follow-up period, and a late mortality rate was 5.2%. During 10 years, thromboembolic event occurred in 8 patients. Four patients had anticoagulant-related bleeding, 4 had paravalvular leak, and 5 underwent re-operations. There was neither structural valve failure nor prosthetic valve endocarditis. Therefore, the actuarial survival rate and the valve-related death-free rate at 10 years were 83.2%, and 96.8%. Of the patients who survived, New York Heart Association class improved significantly (93% in classes II and III preoperatively and 71% in class I postoperatively). Linearized rates for thromboembolism, anticoagulant-related bleeding, and hemolysis were 0.41%, 0.20% and 0.36%/100 patient-years, respectively. The actuarial estimate of incidence free from all complications was 92.0% at 10 years. On the basis of this 10 years' experience, we believe that the SJM valve prosthesis is an excellent mechanical prosthesis for mitral valve replacement, in terms of hemodynamic performance and low thrombogenicity in patients receiving anticoagulants.     

The Hancock II porcine bioprosthesis. A preliminary report

From May 1983 to July 1987 a total of 153 Hancock II porcine bioprostheses have been implanted in 130 patients with a mean age of 59 +/- 8 years (range 29 to 76 years). Mitral valve replacement was performed in 72 patients, aortic valve replacement in 35, and mitral-aortic valve replacement in 23. Cumulative follow-up of 121 survivors is 223 patient-years and 100% complete (range 0.4 to 4.5 years). The actuarial survival rate at 4 years is 88% +/- 8% for mitral, 86% +/- 7.8% for aortic, and 84% +/- 8% for mitral-aortic valve replacement. Minor thomboembolism occurred in two patients (0.9% +/- 0.6%/pt-yr) with an actuarial freedom from emboli at 4 years of 100% for mitral, 96% +/- 3.7% for aortic, and 91% +/- 8.6% for mitral-aortic valve replacement. Anticoagulant-related hemorrhage occurred in 10 patients (4.4% +/- 1.4%/pt-yr) with an actuarial freedom at 4 years of 90% +/- 4.8% for mitral, 89% +/- 5.8% for aortic, and 84% +/- 10.6% for mitral-aortic valve replacement. Failure of the porcine bioprosthesis was observed in three patients with an actuarial freedom at 4 years of 96% +/- 3.6% for aortic, 91% +/- 8% for mitral, and 91% +/- 8.6% for mitral-aortic valve replacement. Actuarial freedom from all porcine bioprosthesis-related complications at 4 years is 85.7% +/- 6.6% for aortic, 79% +/- 9% for mitral, and 70% +/- 13% for mitral-aortic valve replacement. No instances of primary tissue failure occurred.(ABSTRACT TRUNCATED AT 250 WORDS)