Obstruction of St Jude medical valves in the aortic position: a consideration for pathogenic mechanism of prosthetic valve obstruction

Between 1995 and 2000, 8 patients with St. Jude Medical (SJM) valves in the aortic position required 9 redo valve replacement for prosthetic valve obstruction. Obstruction of the prosthetic valve was diagnosed by simultaneous echocardiography and cineradiography, and process of restricted leaflet movement that progressed to hemodynamic impairment was observed by serial studies in three recent patients. An oral anticoagulation was considered to be adequate in all patients except one patient who had withdrawal of warfrain. Pannus was the sole cause of valve obstruction in seven events in 6 patients, and both thrombus and pannus in 2 patients. Pannus overgrowth was found on the inflow aspect of the SJM valve, and involved the ends of the straight edge of the leaflets over pivot guards. These results suggest that pannus might play the primary role in development of obstruction of aortic SJM valves in patients on adequate oral anticoagulation.     

St. Jude Medical prosthetic aortic valve malfunction due to pannus formation.

According to the literature, the incidence of pannus formation with the St. Jude Medical prosthetic aortic valve has been reported at 0.03% and 0.14% (per patient-year), with no case report of St. Jude Medical prosthetic aortic valve malfunction due to pannus formation. Between 1980 and 1999, 1,186 patients underwent aortic valve replacement at our institute. We encountered 2 aortic valve malfunctions due to pannus formation, including the case of a 53-year-old woman who suffered a St. Jude medical aortic valve malfunction 13 years after the initial operation. A second aortic valve replacement was successful and the postoperative course was uneventful. The possibility of pannus formation on St. Jude Medical aortic valves must thus be considered and its mechanism clarified.     

Leaflet arrest in St Jude Medical and CarboMedics valves: an experimental study

Objective: Two patients who suffered acute failure of their St Jude Medical Masters aortic valve prostheses due to leaflet arrest that were unrelated to suture material are presented. It was hypothesized that the valves failed because force applied to bear upon the valve annulus caused the hinge mechanism to become restricted or to arrest. Methods: A study was designed to measure the force that would cause leaflet arrest in three sizes of St Jude Medical Masters valves and CarboMedics mechanical valves. A specially manufactured pushrod device was used to apply a variable force to the sewing cuff, low annulus level, or to the pivot guards of all the valves. Results: For every valve size tested, the St Jude Medical Masters valves required significantly less force applied than did the CarboMedics valves to cause one or both leaflets to arrest (P<0.0004). Conclusions: A force applied on the valve ring of mechanical valves can cause leaflet arrest. The force required to arrest the leaflets is within an order of magnitude of that measured in other in vivo animal studies. We conclude that force on the valve rings in patients after aortic valve surgery could cause leaflet malfunction and even arrest in some patients.     

Assessment of effective orifice area of prosthetic aortic valves with Doppler echocardiography: an in vivo and in vitro study

OBJECTIVES: We sought to evaluate the Doppler assessment of effective orifice area in aortic prosthetic valves. The effective orifice area is a less flow-dependent parameter than Doppler gradients that is used to assess prosthetic valve function. However, in vivo reference values show a pronounced spread of effective orifice area and smaller orifices than expected compared with the geometric area. METHODS: Using Doppler echocardiography, we studied patients who received a bileaflet St Jude Medical valve (n = 75; St Jude Medical, Inc, St Paul, Minn) or a tilting disc Omnicarbon valve (n = 46; MedicalCV, Incorporated, Inver Grove Heights, Minn). The prosthetic valves were also investigated in vitro in a steady-flow model with Doppler and catheter measurements in the different orifices. The effective orifice area was calculated according to the continuity equation. RESULTS: In vivo, there was a wide distribution with the coefficient of variation (SD/mean x 100%) for different valve sizes ranging from 21% to 39% in the St Jude Medical valve and from 25% to 33% in the Omnicarbon valve. The differences between geometric orifice area and effective orifice area in vitro were 1.26 +/- 0.41 cm(2) for St Jude Medical and 1.17 +/- 0.38 cm(2) for Omnicarbon valves. The overall effective orifice areas and peak catheter gradients were similar: 1.35 +/- 0.37 cm(2) and 25.9 +/- 16.1 mm Hg for St Jude Medical and 1.46 +/- 0.49 cm(2) and 24.6 +/- 17.7 mm Hg for Omnicarbon. However, in St Jude Medical valves, more pressure was recovered downstream, 11.6 +/- 6.3 mm Hg versus 3.4 +/- 1.6 mm Hg in Omnicarbon valves (P =.0001). CONCLUSIONS: In the patients, we found a pronounced spread of effective orifice areas, which can be explained by measurement errors or true biologic variations. The in vitro effective orifice area was small compared with the geometric orifice area, and we suspect that nonuniformity in the spatial velocity profile causes underestimation. The St Jude Medical and Omnicarbon valves showed similar peak catheter gradients and effective orifice areas in vitro, but more pressure was recovered in the St Jude Medical valve. The effective orifice area can therefore be misleading in the assessment of prosthetic valve performance when bileaflet and tilting disc valves are compared.     

Long-term outcome after biologic versus mechanical aortic valve replacement in 841 patients

OBJECTIVE: The purpose of this study was to optimize selection criteria of biologic versus mechanical valve prostheses for aortic valve replacement. METHODS: Retrospective analysis was performed for 841 patients undergoing isolated, first-time aortic valve replacement with Carpentier-Edwards (n = 429) or St Jude Medical (n = 412) prostheses. RESULTS: Patients with Carpentier-Edwards and St Jude Medical valves had similar characteristics. Ten-year survival was similar in each group (Carpentier-Edwards 54% 3% versus St Jude Medical 50% 6%; P =.4). Independent predictors of worse survival were older age, renal or lung disease, ejection fraction less than 40%, diabetes, and coronary disease. Carpentier-Edwards versus St Jude Medical prostheses did not affect survival (P =.4). Independent predictors of aortic valve reoperation were younger age and Carpentier-Edwards prosthesis. The linearized rates of thromboembolism were similar, but the linearized rate of hemorrhage was lower with Carpentier-Edwards prostheses (P <.01). Perivalvular leak within 6 months of operation was more likely with St Jude Medical than with Carpentier-Edwards prostheses (P =.02). Estimated 10-year survival free from valve-related morbidity was better for the St Jude Medical valve in patients aged less than 65 years and was better for the Carpentier-Edwards valve in patients aged more than 65 years. Patients with renal disease, lung disease (in patients more than age 60 years), ejection fraction less than 40%, or coronary disease had a life expectancy of less than 10 years. CONCLUSIONS: For first-time, isolated aortic valve replacement, mechanical prostheses should be considered in patients under age 65 years with a life expectancy of at least 10 years. Bioprostheses should be considered in patients over age 65 years or with lung disease (in patients over age 60 years), renal disease, coronary disease, ejection fraction less than 40%, or a life expectancy less than 10 years.     

In vivo hemodynamics of prosthetic St. Jude Medical and Ionescu-Shiley heart valves analyzed by computer

Using a method of our own design, we evaluated intraoperatively the function of prosthetic heart valves. The changing hemodynamics induced by a stress test were assessed by simultaneously measuring the mean transvalvular pressure gradient and the stroke volume. The effective orifice area (EOA) of the valves was determined for each stroke by computer analysis, and this value was compared with the actual orifice area. Data were collected from 19 patients undergoing aortic or mitral valve replacement or both with 17 St. Jude Medical and 12 Ionescu-Shiley valves. The mean pressure gradient increased with tachycardia and an increase in mean left atrial pressure in the mitral position, but decreased with a decrease in cardiac output and peak left ventricular pressure in the aortic position. The St. Jude Medical valve had a smaller mean pressure gradient than the Ionescu-Shiley bioprosthesis. For both valves, the EOA increased with valve size. The St. Jude Medical valve had a greater EOA than the Ionescu-Shiley bioprosthesis, regardless of the valve size (p less than 0.005). However, the performance of prosthetic leaflets was better with the Ionescu-Shiley bioprosthesis than with the St. Jude Medical mechanical valve (p less than 0.001). This method involving computer analysis of each cardiac cycle proved to be useful for evaluating prosthetic heart valve function in the presence of changing hemodynamics.     

Valve thrombosis of St. Jude Medical prosthesis; report of three cases

Three cases with valve thrombosis of St. Jude Medical prosthesis (SJM valve) are reported. Incidence of valve thrombosis of SJM valve was 0.15%/patient-year. Cineradiography was useful to make the diagnosis. SJM valves were implanted with the hinges anatomically oriented in mitral position, and in both aortic and tricuspid positions with the leaflet opening parallel to the ventricular septum. Therefore, we recommend that SJM valve should be placed with the hinge antianatomically oriented in mitral position, and in both aortic and tricuspid positions with the leaflet opening to be perpendicular to the interventricular septum, respectively.     

An assessment of the mechanical properties of leaflets from four second-generation porcine bioprostheses with biaxial testing techniques

The aim of this study was to determine whether second-generation porcine bioprostheses, glutaraldehyde fixed at pressures said to be less than 4 mm Hg, exhibit more natural leaflet material properties than earlier valves fixed at 80 to 100 mm Hg. Biaxial mechanical testing techniques were used to compare Carpentier-Edwards SAV, St. Jude Medical BioImplant, Hancock II, and Medtronic Intact bioprostheses (12 leaflets from four valves in each case) with fresh porcine aortic valves and high pressure-fixed Carpentier-Edwards 6625 bioprostheses (14 leaflets from five valves in each case). The circumferential extensibility of leaflets from Medtronic Intact bioprostheses and from fresh porcine aortic valves were not significantly different (p greater than 0.05), whereas leaflets from the other second-generation valves tested and from Carpentier-Edwards 6625 valves were highly inextensible in the circumferential direction. The radial material properties of leaflets from all bioprostheses differed from those of fresh porcine aortic valves, which were very extensible with a high pretransitional compliance. The radial extensibility and compliance of Hancock II, St. Jude Medical BioImplant, and Carpentier-Edwards 6625 leaflets were not significantly different (p greater than 0.05). In the radial direction, Carpentier-Edwards SAV and Medtronic Intact valve leaflets were substantially more extensible than Carpentier-Edwards 6625 leaflets (p less than 0.01), whereas Medtronic Intact leaflets were more compliant than all other bioprostheses. These data demonstrate (1) that second-generation porcine bioprosthetic valves do not necessarily exhibit more natural leaflet material properties than earlier high pressure-fixed xenografts and (2) that Medtronic Intact valve leaflets have material properties most closely approximating the fresh porcine aortic valve.     

Hemodynamic and hemolytic features of the St. Jude Medical valve prostheses

We performed valvular replacement in 86 cases (108 valves, 43 males, 43 females) from July 1978 to July 1981 with St. Jude Medical valves which utilize two discs made of pyrolytic carbon and employ a bileaflet central opening system. Ages ranged from 13 to 68 years (average 42.3). For all cases in this study, we performed anti-coagulant therapy. The incidence of thromboembolic complication was zero. With regard to postoperative clinical evaluation on valve function and chronic hemolysis, we compared the cases of St. Jude Medical valves with those of Starr-Edwards (S.E.) valves (aortic: Model 2320, mitral: Model 6400), Carpentier-Edwards (C.E.) valves and cases of open mitral commissurotomy. As for valve function such as left atrioventricular diastolic pressure gradient, mitral effective orifice area both at rest and on exercise, the St. Jude Medical valve yielded best results. Next was the C.E. and third was the S.E. The results of the St. Jude Medical valve group and those of the open mitral commissurotomy group were equivalent. In comparison with ball type cardiac valve prostheses and bioprostheses, the St. Jude Medical valve has excellent hemodynamic characteristic. Concerning hemolysis, the St. Jude Medical was below only the C.E., however the degree of hemolysis was so low that the St. Jude Medical valve holds great promise as central flow mechanical valve prostheses.     

Clinical evaluation of St Jude Medical Hemodynamic Plus versus standard aortic valve prostheses: The Italian multicenter, prospective, randomized study

OBJECTIVE: Hemodynamic and clinical performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus aortic valves (St Jude Medical, Inc, St Paul, Minn) were compared with those of 21-mm and 23-mm St Jude Medical standard cuff aortic valves in the first such multicenter, prospective, randomized study. Hemodynamic Plus valves are mechanical, bileaflet prostheses suitable for the small aortic anulus. METHODS: Patients with 21-mm and 23-mm anulus diameters were randomized to receive either a Hemodynamic Plus or a standard cuff valve. Postoperatively and at 6 months after the operation, patients underwent 2-dimensional Doppler echocardiography. Ejection fraction, cardiac output, peak gradient, mean gradient, effective orifice area, effective area index, and performance index were calculated. Postoperative and 6-month echocardiographic measurements and their variations across observation times were analyzed statistically. RESULTS: Of the 140 patients enrolled, 5 died at operation and 1 died of aortic dissection during the follow-up period. Eight patients were lost to follow-up. A total of 125 patients completed the study. In 1 patient a sewing cuff escaped intraoperatively. At 6 months the 21-mm and 23-mm Hemodynamic Plus valves showed significantly lower peak gradients and mean gradients than those of the 21-mm and 23-mm standard cuff valves. The 21-mm Hemodynamic Plus valves had gradients similar to those of the 23-mm Hemodynamic Plus valves. The effective orifice area did not differ significantly between the Hemodynamic Plus and standard cuff valves at either measurement. No valve mismatch was found in the 4 groups of patients. A more enhanced decrease of peak gradients and mean gradients and a more enhanced increase of effective orifice areas, effective area indices, and performance indices were found across observation times for patients with Hemodynamic Plus valves compared with those with standard cuff valves. CONCLUSIONS: Clinical hemodynamic performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus valves correspond closely with those of standard cuff valves, and gradients are substantially better than those of standard cuff valves of the same diameter. Therefore, use of this valve may minimize the need for aortic anulus enlargement. Early follow-up results with the Hemodynamic Plus valves were excellent, although more time is required to confirm this outcome.     

Twenty-year comparison of tissue and mechanical valve replacement

OBJECTIVE: We sought to compare outcomes with tissue and St Jude Medical mechanical valves over a 20-year period. METHODS: Valve-related events and overall survival were analyzed in 2533 patients 18 years of age or older undergoing initial aortic, mitral, or combined aortic and mitral (double) valve replacement with a tissue valve (Hancock, Carpentier-Edwards porcine, or Carpentier-Edwards pericardial) or a St Jude Medical mechanical valve. Total follow-up was 13,390 patient-years. There were 666 St Jude Medical aortic valve replacements, 723 tissue aortic valve replacements, 513 St Jude Medical mitral valve replacements, 402 tissue mitral valve replacements, 161 St Jude Medical double valve replacements, and 68 tissue double valve replacements. The mean age was 68 +/- 13.3 years (St Jude Medical valve, 64.5 +/- 12.9; tissue valve, 72.0 +/- 12.6). RESULTS: There were no overall differences in survival between tissue and mechanical valves. Multivariable analysis indicated that the type of valve did not affect survival. Analysis by age less than 65 years or 65 years or older and presence or absence of coronary disease revealed similar long-term survival in all subgroups. The risk of hemorrhage was lower in patients receiving tissue aortic valve replacements but was not significantly different in patients receiving mitral valve or double valve replacements. Thromboembolism rates were similar for tissue and mechanical valve recipients. However, reoperation rates were significantly higher in patients receiving both aortic and mitral tissue valves. The reoperation hazard increased progressively with time both in patients receiving aortic and in those receiving mitral tissue valves. Overall valve complications were initially higher with mechanical aortic valves but not with mechanical mitral valves. However, valve complication rates later crossed over, with higher rates in tissue valve recipients after 7 years in patients undergoing mitral valve replacement and 10 years in those undergoing aortic valve replacement. CONCLUSIONS: Tissue and mechanical valve recipients have similar survival over 20 years of follow-up. The primary tradeoff is an increased risk of hemorrhage in patients receiving mechanical aortic valve replacements and an increased risk of late reoperation in all patients receiving tissue valve replacements. The risk of tissue valve reoperation increases progressively with time.     

Comparison of noninvasive techniques in evaluation of the Bj?rk-Shiley and the St. Jude Medical valve prostheses in mitral position

Pressure gradients and left ventricular function were assessed by Doppler echocardiography in 50 patients with Bj?rk-Shiley mitral valve and 50 patients with St. Jude Medical valve prosthesis. There was correlation between pressure gradient and valve size, and between effective valve orifice area and valve size for St. Jude Medical valve. These correlations were not found in Bj?rk-Shiley valve. Clinical improvement and cardiac function were quite satisfactory in 20 patients with Bj?rk-Shiley valve and in 32 patients with St. Jude Medical valve whose pressure gradients were less than 10 mmHg. Twenty eight of 50 patients with Bj?rk-Shiley valve and 42 of 50 patients with St. Jude Medical valve showed good response to the exercise test. Eight patients underwent reoperation because of unacceptably high gradient caused by thrombus and pannus formation. The patients who show high pressure gradient across the valve prosthesis should be followed up cautiously.     

Mitral Valve Stenosis Caused by Abnormal Pannus Extension over the Prosthetic Ring and Leaflets After Duran Ring Mitral Annuloplasty

Abstract   We treated a 61-year-old woman with mitral stenosis caused by pannus formation after Duran ring annuloplasty. Pannus overgrowth on the ring with extension onto both leaflets narrowed the mitral orifice and severely restricted the mobility of the valve leaflets. Mitral valve replacement with a St. Jude Medical mechanical heart valve prosthesis was successfully performed, and the postoperative course was uneventful. Patients undergoing Duran ring annuloplasty should be followed up with the consideration of possible mitral stenosis caused by pannus extension, as the cause for pannus formation remains unclear.     

Comparative Rest and Exercise Hemodynamics of Allograft and Prosthetic Valves in the Aortic Position

Background. Allograft aortic valve replacement has gained widespread acceptance. However, there is little information about in vivo allograft valve function at rest and during exercise.

Methods. Cardiac catheterization was performed to measure hemodynamic variables at rest and during supine bicycle exercise in 44 patients who had had aortic valve replacement using allograft valves or Bicer or St. Jude Medical prosthetic valves 19 to 27 mm in diameter. Sixteen patients received an allograft valve; 17, a Bicer valve; and 11, a St. Jude Medical valve. There were no significant differences between the three groups in age, body surface area, left ventricular end-systolic and end-diastolic volume indices, exercise cardiac index, exercise heart rate, or work load achieved. Left ventricular and ascending aortic pressures were measured simultaneously according to the transseptal method.

Results. The mean pressure gradient was generally higher for the Bicer and St. Jude Medical valves than for the allograft valves, both at rest and during exercise. Significant differences were obtained in patients with small-sized valves (21 and 23 mm); pressure gradients were higher in the prosthetic valve groups. In patients with large-sized prosthetic valves (25 mm), there were no significant differences between the three groups at rest and during exercise. However, there was no pressure gradient at all for allograft valves.

Conclusions. Exercise cardiac catheterization confirms that the allograft aortic valve is an ideal substitute from the hemodynamic aspect, particularly in patients with a small aortic root and in those who perform strenuous exercise.     

Usefulness of a multidetector-row computed tomography scanner for detecting pannus formation

BACKGROUND: Prosthetic valve dysfunction (PVD) as a result of pannus or thrombus formation is an infrequent but serious complication. Currently available diagnostic tools, however, are insufficient to detect a minute pannus and thrombi. The use of a more advanced diagnostic image, multidetector-row computed tomography scanner, may enable us to determine the anatomic and functional causes of PVD. METHODS: Patients who underwent aortic valve replacement with a St. Jude Medical valve were examined by transthoracic echocardiography and cineradiography to diagnose PVD. Sixteen patients with PVD (PVD group) and 12 patients with normal prosthetic valve function (control group) were studied using the multidetector-row computed tomography scanner. The multidetector-row computed tomography findings in 2 patients with PVD were validated by the observations during reoperation. RESULTS: In 13 of 16 patients (81%) in the PVD group and 3 of 12 patients (25%) in the control group, multidetector-row computed tomography demonstrated that an abnormal small tissue, regarded as pannus, was found to extend from the left ventricular septum into the pivot guard. These findings were confirmed by the observations during reoperation in 2 patients in the PVD group. CONCLUSIONS: Multidetector-row computed tomography can be a useful diagnostic technique for anatomic and functional evaluation of PVD as a result of pannus formation.     

Clinical assessment of the St. Jude medical cardiac prosthesis. A 5-year experience

Mechanical prosthetic valves have established their long-term durability, but the incidence of thromboembolism has been less satisfying. Therefore, the search for the perfect valve continues. The choice of replacing a cardiac valve with a prosthetic valve is based upon its hemodynamics, durability, thromboembolic and hemolytic characteristics. The hemodynamic assessment of the St. Jude Valve demonstrates that it performs well in the aortic, mitral, and tricuspid positions. The central bileaflet flow design leads to minimal gradients, even in the small valves which make it ideal for its use in children. The purpose of its all-pyrolite construction is to decrease the incidence of thromboembolism. Replacement of heart valves with the St. Jude Medical prosthesis was initiated in April, 1979. An analysis of all patients undergoing valve replacement between April 1, 1979, and June 1, 1984, was carried out to assess the durability, incidence of thrombosis, and thromboembolic as well as other complications.     

A retrospective comparative study of aortic valve replacement with St. Jude medical and medtronic-hall prostheses: a 20-year follow-up study

OBJECTIVE: To compare the long-term clinical outcome of patients who underwent aortic valve replacement with St. Jude Medical and Medtronic-Hall mechanical prostheses. DESIGN: From June 1978 to June 1982, 43 Medtronic-Hall and 48 St. Jude Medical mechanical valves were implanted in 90 consecutive patients with aortic valve disease, and their clinical outcome was retrospectively assessed. RESULTS: At 20 years in the St. Jude Medical group and in the Medtronic-Hall group the actuarial rates of overall survival were 50 and 49% (p = NS), of cardiovascular survival 66 and 63% (p = NS), of valve-related survival 95 and 91% (p = NS), of freedom from major valve-related complications 83 and 45% (p = 0.005), from major cerebrovascular events 93 and 71% (p =0.06), from valve thrombosis 97 and 89% (p = NS), from aortic valve reoperation 93 and 88% (p = NS), from major bleeding 96 and 82% (p = 0.04), and from endocarditis 93 and 82% (p = NS), respectively. The linearized rate of overall major aortic valve prosthesis-related complications was 3.47%/year in the Medtronic-Hall valve group and 1.53%/year in the St. Jude Medical valve group (p = 0.003). Multivariate analysis showed that the type of prosthesis was predictive of freedom from valve-related complications (p = 0.01; 2.849; C.I. 95%: 1.246-6.516). CONCLUSION: The aortic St. Jude Medical mechanical valve seems to be associated with a slightly lower rate of long-term valve-related morbidity than the aortic Medtronic-Hall mechanical valve. Because of the small patient population and the retrospective nature of the study, the choice between these two prostheses should not be made only on the basis of these findings. However, these results suggest a reappraisal for further comparative studies with such an extended follow-up.     

Surgical treatment of the prosthetic valves in reoperation

Surgical treatment and problems in patients required reoperation for malfunctioning prosthetic valves are reviewed in our institute. The cinefluoroscopy and pulse doppler echocardiography were helpful for diagnosis of artificial valve dysfunction. In recent two decades valve replacement were performed in 382 cases and number of re-implanted valve were 469. Among them the cases of reoperation were 21 and reimplanted valves were 25 (5.6%); 4.7% in aortic, 5.0% in mitral, 6.7% in tricuspid position. Three cases of those patients had three operations. Main causes of reoperation were primary tissue failure in Carpentier-Edwards porcine xenograft (6 cases, 23%) and cloth wear in Starr-Edwards ball valve (9 cases, 38%) and thrombosis in St. Jude Medical bi-leaflet valve (3 cases, 15%). In most cases St. Jude Medical valve were chosen for the alternative prosthetic valve in reoperation. We applied IABP support to seven patients for severe low cardiac output syndrome after the operation and overall mortality was 24% in reoperation. It concluded that St. Jude Medical valve may be most reliable because of low incidence of postoperative complication in our institute.     

Baseline Platelet Aggregation and Major Receptor Expression Predict Subsequent Activity Following Thrombolysis for Acute Myocardial Infarction

Objective - To compare the long-term clinical outcome of patients who underwent aortic valve replacement with St. Jude Medical and Medtronic-Hall mechanical prostheses. Design - From June 1978 to June 1982, 43 Medtronic-Hall and 48 St. Jude Medical mechanical valves were implanted in 90 consecutive patients with aortic valve disease, and their clinical outcome was retrospectively assessed. Results - At 20 years in the St. Jude Medical group and in the Medtronic-Hall group the actuarial rates of overall survival were 50 and 49% ( p = NS), of cardiovascular survival 66 and 63% ( p = NS), of valve-related survival 95 and 91% ( p = NS), of freedom from major valve-related complications 83 and 45% ( p = 0.005), from major cerebrovascular events 93 and 71% ( p = 0.06), from valve thrombosis 97 and 89% ( p = NS), from aortic valve reoperation 93 and 88% ( p = NS), from major bleeding 96 and 82% ( p = 0.04), and from endocarditis 93 and 82% ( p = NS), respectively. The linearized rate of overall major aortic valve prosthesis-related complications was 3.47%/year in the Medtronic-Hall valve group and 1.53%/year in the St. Jude Medical valve group ( p = 0.003). Multivariate analysis showed that the type of prosthesis was predictive of freedom from valve-related complications ( p = 0.01; 2.849; C.I. 95%: 1.246-6.516). Conclusion - The aortic St. Jude Medical mechanical valve seems to be associated with a slightly lower rate of longterm valve-related morbidity than the aortic Medtronic-Hall mechanical valve. Because of the small patient population and the retrospective nature of the study, the choice between these two prostheses should not be made only on the basis of these findings. However, these results suggest a reappraisal for further comparative studies with such an extended follow-up.     

Mitral and mitro-aortic valve replacement with Sorin Bicarbon valves compared with St. Jude Medical valves

OBJECTIVE: We assessed the clinical results of two bileaflet mechanical valves: the St. Jude Medical (SJM) and the Sorin Bicarbon (Sorin Bicarbon) used either in single mitral valve replacement (MVR) or in double, aortic and mitral, valve replacement (DVR). METHODS: Between September 1990 and November 1995, 217 patients received either a St. Jude Medical (n=134) or a Sorin Bicarbon (n=86): 136 mitral valve replacement with 83 St. Jude Medical and 53 Sorin Bicarbon and 84 double valve replacement with 51 St. Jude Medical and 33 Sorin Bicarbon. There was no difference between both St. Jude Medical and Sorin Bicarbon cohorts in respect of mitral valve physiopathology, etiology of valve disease, associated lesions, echocardiographic and hemodynamic data. The only significant preoperative difference was the age of patients within the double valve replacement group and the size of implanted valves within the mitral valve replacement group. Follow-up was 100% complete with a mean of 39+/-18 months, ranging between 6 and 68 months. The total follow-up was 657 patient-years (pt-y): 396 pt-y in the mitral valve replacement group and 274 pt-y in the double valve replacement group. RESULTS: Hospital mortality (St. Jude Medical: 2.2%; Sorin Bicarbon: 6.9%) and late mortality (St. Jude Medical: 8.4%; Sorin Bicarbon: 6.3%) were not significantly different. Ten deaths were considered valve-related (St. Jude Medical 6, Sorin Bicarbon 4). The estimated 4-yr overall survival, including hospital mortality, was for St. Jude Medical--mitral valve replacement: 89+/-4% and St. Jude Medical--double valve replacement: 93+/-4%, and for Sorin Bicarbon--mitral valve replacement: 87+/-5% and Sorin Bicarbon--double valve replacement: 91+/-5%. The linearized incidence (% per pt-y) of valve-related complications was 6.39 in the St. Jude Medical cohort and 9.2 in the Sorin Bicarbon cohort. The linearized incidence (% pt-y) of the prevalent complication, valve thromboembolism and bleeding, was for St. Jude Medical-mitral valve replacement: 3.41, St. Jude Medical--double valve replacement: 3.16 and for Sorin Bicarbon--mitral valve replacement: 2.17 and Sorin Bicarbon--double valve replacement: 3.67. The differences between each group of an estimated 4-yr freedom from combined thromboembolism and bleeding were not significant (St. Jude Medical--mitral valve replacement: 90+/-4%, St. Jude Medical--double valve replacement: 84+/-6%, and for Sorin Bicarbon--mitral valve replacement: 94+/-3% and Sorin Bicarbon--double valve replacement: 75+/-17%). CONCLUSIONS: In this clinical non-randomized study, there was no evidence of any significant difference between St. Jude Medical and Sorin Bicarbon valves over a 4-yr follow-up.