CarboMedics mechanical prosthesis: performance at eight years

BACKGROUND AND AIM OF THE STUDY: The bileaflet St. Jude Medical mechanical prosthesis has been implanted for over 20 years. The purpose of this study was to evaluate the clinical performance of the bileaflet CarboMedics (CM) prosthesis, which was introduced in 1986. METHODS: The CM prosthesis was implanted in 1,258 patients (709 males, 549 females; mean age 60.9 +/- 12.3 years) between 1989 and 1997. The prosthesis distribution was aortic valve replacement (AVR) 613; mitral valve replacement (MVR) 447; and multiple replacement (MR) 231. Coronary artery bypass (CAB) was performed in 334 (26.6%) patients; previous procedures had been performed in 346 (27.5%). The age distribution was <60 years (n = 527), 61-70 years (n = 424) and >70 years (n = 307). Risk factors assessed were age or age groups, gender, CAB, previous surgery, rhythm, valve position, status and NYHA functional class. The total follow up was 4,765.0 patient-years (pt-yr), and was 98.4% complete. RESULTS: The early mortality rate was 5.6% (AVR 4.8%, MVR 3.7%, MR 11.5%). The late mortality rate was 3.7%/pt-yr (n = 174), and valve-related mortality 1.1%/pt-yr (n = 50). The total thromboembolism (TE) rate was 4.1%/pt-yr (n = 195) (p = NS by valve position); the major TE rate was 1.9%/pt-yr and fatal TE rate 0.31%/pt-yr (n = 15). The valve thrombosis rate was 0.31%/pt-yr (n = 15; 11 MVR, four MR). The fatal thrombosis rate was 0.06%/pt-yr (n = 3; two MVR, one MR). The hemorrhage rate was 2.7%/pt-yr (n = 128) and fatal hemorrhage rate 0.4%/pt-yr (n = 20). The reoperation rate was 1.0%/pt-yr (n = 46), fatal 0.1%/pt-yr (n = 5). The actuarial freedom from overall TE at eight years was 77.3 +/- 2.8%; major TE 88.5 +/- 1.6%, and hemorrhage 76.4 +/- 3.2% (all p = NS by valve position). There were no independent predictors of overall TE and TE exclusion of early events. The only predictor for TE major was status (emergency > urgent > elective). The actuarial freedom from valve-related mortality at eight years was 91.4 +/- 1.8% (p = NS by position) (actual freedom 93.0 +/- 1.3%). The actuarial freedom from valve-related reoperation was 91.1 +/- 2.4% (p <0.05; AVR > MVR and MR, MVR > MR) (actual freedom 92.2 +/- 2.7%). Overall survival rate at eight years was 68.2 +/- 2.3% (p <0.05; AVR > MVR and MR, MVR > MR). CONCLUSION: The clinical performance of the CarboMedics mechanical prosthesis is satisfactory when implanted in the mitral, aortic and multiple positions.     

Five-year follow up of the ATS mechanical heart valve

BACKGROUND AND AIM OF THE STUDY: Between January 1, 1997 and December 31, 2001, a total of 342 patients underwent aortic valve replacement (AVR) or mitral valve replacement (MVR) with the ATS Medical prosthesis. The initial three-year phase of this study took place under a United States Food and Drug Administration-approved investigational device exemption study. The study aim was to determine the incidence of valve-related events in up to five years of follow up after valve implantation, and to assess patient disturbance from valve noise. METHODS: Patients were consecutively enrolled to undergo AVR or MVR with the ATS prosthesis. Follow up studies were conducted by patient questionnaire and/or telephone call. Follow up was 96% complete. AVR was conducted in 246 patients (80 with coronary bypass), and MVR in 96 patients (29 with coronary bypass). RESULTS: The overall operative mortality was 2.6% (n = 9; AVR 3.2%, n = 8; MVR 1.0%, n = 1), with two deaths being valve-related (0.6%). In 878 patient-years (pt-yr) of follow up (613 pt-yr for AVR; 265 pt-yr for MVR) there were an additional 22 deaths. Five deaths (0.6%/pt-yr) were valve-related: two were neuroembolic (both MVR), one from endocarditis (AVR), and two from bleeding events (both AVR). Late valve-related complications (>30 days) included 17 episodes of major bleeding (11 AVR, 1.8%/pt-yr; six MVR, 2.3%/pt-yr), five permanent neuroembolic events (four AVR, 0.7%/pt-yr; one MVR, 0.4%/pt-yr); 16 transient neuroembolic events (10 AVR, 1.6%/pt-yr; six MVR, 2.3%/pt-yr); three transient peripheral emboli (two AVR, 0.3%/pt-yr; one MVR, 0.4%/pt-yr); four paravalvular leaks (two AVR, 0.3%/pt-yr; two MVR, 0.8%/pt-yr); and one episode of valve thrombosis (MVR, 0.4%/pt-yr; AVR, 0%/pt-yr). Reoperation was required in two patients: one AVR (paravalvular leak, 0.2%/pt-yr) and one MVR (replacement due to thrombosis, 0.4%/pt-yr). CONCLUSION: These results indicate that intermediate-term results with the ATS mechanical prosthesis continue to be excellent, though further long-term follow up is warranted.     

Single-center experience with the On-X prosthetic heart valve between 1996 and 2005

BACKGROUND AND AIM OF THE STUDY: Herein are presented long-term results for the On-X mechanical heart valve. All On-X heart valve recipients since the first implantation worldwide at the University of Bochum in September 1996 were followed retrospectively; the present authors' single-center experience over a period of almost 10 years is reported. METHODS: A total of 428 patients (255 males, 173 females; mean age 62.7 years) underwent either aortic valve replacement (AVR; n = 264) or mitral valve replacement (MVR; n = 164) using the On-X prosthesis. Preoperatively, 329 patients (76.8%) were in NYHA class III or IV. Approximately 5% of AVR and 23% of MVR patients had undergone previous cardiac surgery. Concomitant surgery was performed in 189 patients (44.2%). The mean follow up was 3.9 years, and cumulative follow up 1,625 patient-years (pt-yr); the overall follow up rate was 98.7%. RESULTS: Early mortality (< or = 30 days) was 3.7% after AVR and 14.0% after MVR, with valve-related mortality rates of 0.4% and 1.2%, respectively. At autopsy (n = 12) all implants were intact. Freedom from valve-related death at nine years was 85.0 +/- 3.9% after AVR and 87.6 +/- 3.2% after MVR. The overall survival rate was 67.9 +/- 4.3% after AVR and 52.7 +/- 8.1% after MVR. The linearized rate of thromboembolism for AVR and MVR was 1.49%/pt-yr and 1.61%/pt-yr; of thrombosis 0%/pt-yr and 0.35%/pt-yr; of hemorrhage 0.93%/pt-yr and 1.43%/pt-yr; of endocarditis 0.37%/pt-yr and 0.17%/pt-yr; of non-structural failure 0.18%/pt-yr and 1.43%/pt-yr; and of reoperation 0.28%/pt-yr and 0.53%/pt-yr. There were no cases of structural valve failure. CONCLUSION: After almost one decade of clinical experience in a single center, the On-X heart valve continues to be reliable and effective.     

Nine-year follow up of the omnicarbon prosthesis in the aortic position

BACKGROUND AND AIM OF THE STUDY: Clinical experience with the Omnicarbon mechanical valve implanted in the aortic position is reported in this retrospective survey. METHODS: A total of 110 patients (mean age 56 years) undergoing isolated aortic valve replacement with Omnicarbon mechanical prostheses at the authors' institution between November 1991 and October 2000 was included. Follow was available in 94.5% of patients (mean follow up 4 years per patient; total follow up was 415 patient-years (pt-yr)). RESULTS: Hospital mortality was 3.6%. There were no instances of valve thrombosis or structural failure. The incidence of valve-related complications (linearized rates in events per 100 pt-yr/actuarial freedom at 9 years, in %) was: valve-related mortality 2.4+/-0.7 / 80.3+/-8.0; non-structural failure 0.7+/-0.4 / 93.8+/-4.2; thromboembolism 0.2+/-0.2 / 99.0+/-1.0; anticoagulant-related hemorrhage 0.9+/-0.5 / 93.7+/-3.3; prosthetic valve endocarditis 0.2+/-0.2 / 99.0+/-1.0; and reoperation 0.7+/-0.4 / 93.8+/-4.2. CONCLUSION: In the authors' experience the Omnicarbon mechanical prosthesis provides a good clinical performance for up to nine years in the aortic position.     

Aspire porcine bioprosthesis: ten years' experience

BACKGROUND AND AIM OF THE STUDY: Clinical results of this multicenter study of the Aspire porcine valve were reported previously at eight years; the present report provides an update of valve performance to 10 years postoperatively. METHODS: A total of 749 patients (60% males; mean age 73+/-7 years) underwent implantation with the Aspire (Tissuemed) porcine bioprosthesis between 1991 and 2002, at three institutions. Follow up was complete for 98% of the cohort. The mean follow up period was 51.6+/-39.6 months (range: 0-181 months); total follow up was 3,159 patient-years (pt-yr). RESULTS: There were 617 aortic valve replacements (AVR), 96 mitral valve replacements (MVR) and 32 double valve replacements. There were 62 deaths (8.3%), one of which was valve-related. The late mortality rate was 9.3% per pt-yr (1.2%/pt-yr valve-related). Actuarial freedom from complications at 10 years was: thromboembolism 76+/-4% (2.6%/pt-yr); hemorrhage 73+/-4% (2.8%/pt-yr); structural valve deterioration (SVD) 96+/-2% (0.2%/pt-yr); non-structural deterioration 99+/-1% (0.1%/pt-y); prosthetic valve endocarditis 97+/-1% (0.3%/pt-yr); and reoperation 97+/-1% (0.4%/pt-yr). In patients aged >70 years, the 10-year actuarial freedom from SVD was 98+/-2% for AVR and 93+/-7% for MVR. Preoperative atrial fibrillation (AF) was a significant predictor of late mortality (p <0.001), thromboembolism (p = 0.05) and hemorrhage (p = 0.01). CONCLUSION: The Aspire porcine bioprostheses is a reliable choice for a tissue valve, for both the aortic and mitral positions, especially in patients aged >70 years. In elderly patients the presence of AF is a significant predictor of early and late mortality and morbidity.     

The CarboMedics 'Top-Hat' aortic valve prosthesis: short-term results

BACKGROUND AND AIM OF THE STUDY: The CarboMedics 'Top-Hat' aortic valve prosthesis has been specifically designed for supra-annular implantation. The aim of this study was to assess the safety of implantation of this prosthesis by reporting the short-term results of follow up. METHODS: Between May 1993 and May 1998, 128 patients (mean age 62.5 +/- 9.8 years; range: 22-76 years) received a CarboMedics 'Top-Hat' prosthesis at our institution. Among patients, 55% were in NYHA functional classes III or IV, and 54.7% had an isolated aortic valve replacement. Associated procedures were: coronary artery bypass grafting (25.7%), double valve replacement (17.1%), treatment of ascending aortic aneurysm (4.7%) and miscellaneous (5.5%). Follow up was 100% complete; total cumulative follow up was 265 patient-years (pt-yr) (range: 2-60 months). RESULTS: The overall mortality rate was 1.5% (two deaths). The operative mortality rate was 0.8% (one death); this patient died from neurological complications after operation for aortic dissection. The other patient died on postoperative day 40 from a massive cerebral hemorrhage. Four patients presented thromboembolic events; in all cases these were reversible ischemic neurologic deficits. One patient had a nonstructural deterioration (endocarditis) and required reoperation. Freedom from mortality was 98.3% at five years (linearized rate of 0.75%/pt-yr). Freedom from thromboembolism was 63.1% at five years (linearized rate 1.5%/pt-yr). CONCLUSION: Short-term results with the CarboMedics 'Top-Hat' prosthesis were satisfactory, with low rates of morbidity and mortality. As this prosthesis has demonstrated a good reliability to date, we have continued its implantation in our institution, and long-term follow up will be necessary to confirm these good early results.     

Seventeen-year clinical results of 1,037 Mitroflow pericardial heart valve prostheses in the aortic position

BACKGROUND AND AIM OF THE STUDY: It is generally believed that the pericardial tissue valve is associated with a greater propensity to early structural failure and subsequent valve-related complications. However, a modified valve design during recent years has considerably improved the clinical durability of this bioprosthesis. METHODS: Between April 1986 and December 2003, single Mitroflow pericardial valve prostheses were inserted in the aortic position in 1,037 patients (mean age 72.4 +/- 8.4 years). Coronary artery bypass grafting (CABG) was performed in 373 patients (36%). Preoperative echocardiographic findings of structural valve deterioration (SVD) were confirmed at reoperation. Total follow up was 5,022 patient-years (pt-yr) (mean 4.85 +/- 4.7 years) and was 99.7% complete (three patients lost). RESULTS: Early (30-day) mortality was 2.9% for elective surgery; 434 patients (41.9%) died during the follow up period. Actuarial survival at 17 years was 23.2 +/- 2%. Actuarial freedom from valve-related mortality at 17 years was 92.0 +/- 2.2%, whereas the linearized mortality rate was 0.4%/pt-yr. Linearized valve-related complications occurred at a rate of 3.6%/pt-yr (n = 122). SVD of Mitroflow bioprostheses occurred at a rate of 1.0%/pt-yr, and caused stenosis (36.7%), insufficiency (20.4%) and combined stenosis and insufficiency (42.9%). Actual freedom from SVD at 17 years was 95.3 +/- 0.7% for all patients, 96.2 +/- 0.6% for those aged > 60 years, and 99.0 +/- 0.4% for those aged > 70 years. CONCLUSION: The Mitroflow pericardial bioprosthesis, in the aortic position, provides an excellent clinical performance and a low rate of valve-related morbidity, mortality and reoperation for up to 17 years. The prosthesis also demonstrates satisfactory hemodynamic performance, and is therefore recommended for patients aged > or = 70 years and for those aged 60-69 years with comorbidities.     

6 years clinical experience with the TEKNA bivalve heart valve prosthesis

OBJECTIVE: The revised Edwards-Duromedics valve was introduced onto the market in June 1990. In September 1993, the producer changed the name of the valve to TEKNA, which is a low profile, bileaflet, mechanical prosthesis with a self-irrigating hinge mechanism. The results of a prospective follow-up study after valve replacement with this prosthesis are presented. METHODS: From November 1990 to December 1996, 173 TEKNA prostheses were implanted in 161 patients (73 men, 88 women), either in the aortic (AVR; 48.4%), mitral (MVR; 44.1%), or aortic and mitral positions (DVR; 7.5%). Patient ages ranged from 17 to 83 years (mean age 59.2 +/- 8.7 years). Follow-up was 97.5% complete, comprising 433.15 patient-years for a mean follow-up of 34.8 +/- 23 months. RESULTS: Overall operative (30-day) mortality was 4.97%. Fifteen patients died in the late period, corresponding to a linearized late mortality rate of 3.5%/pt-yr. Actuarial survival at six years was 75.3% +/- 6.2% overall. The actuarial freedom from complications was calculated as follows (linearized rates in parentheses): valve-related mortality 91.3% +/- 5.1% (0.92%/pt-yr); thromboembolism 94.2% +/- 2.5% (1.62%/pt-yr); valve thrombosis 98.6 +/- 1.0% (0.46%/pt-yr); bleeding events 85.9% +/- 4.7% (2.77%/pt-yr); prosthetic valve endocarditis 98.6 +/- 0.9% (0.46%/pt-yr); nonstructural dysfunction 93.2 +/- 3.2% (1.38%/pt-yr); reoperation 87.1 +/- 5.3% (2.08%/pt-yr). Functional class according to NYHA was improved from preoperatively 72.05% in III or IV to 6-year postoperative 94.2% in I or II. CONCLUSION: The clinical performance of the TEKNA valve is quite satisfactory, with low incidence of valve-related complications. No structural deterioration has been observed. Further, the patients physical ability and quality of life were significantly improved.     

Valve surgery in renal dialysis patients

BACKGROUND AND AIM OF THE STUDY: Mechanical valves are used in dialysis patients due to the presumed rapid degeneration of tissue valves. The study aim was to compare the results of mechanical and tissue valves placed in renal dialysis patients. METHODS: Information obtained from a computer-based valve replacement database, telephone interviews and patient charts was reviewed for follow up data. RESULTS: Between 1991 and 2004, 50 dialysis patients underwent left-sided valve replacement. Of these patients, 17 received 21 St. Jude Medical mechanical valves (12 aortic, nine mitral), and 33 received 39 tissue valves (19 aortic, 20 mitral). The mean follow up for the mechanical and tissue valve groups was 19.4 +/- 21.3 and 21.4 +/- 18.7 months, respectively. Mortality at four years was 65% (11/17) for the mechanical valve group, and 42% (14/33) for the tissue valve group (p = 0.15). Freedom from reoperation was not significantly different. The tissue valve group had significantly higher Kaplan-Meier freedom from thromboembolism (100% versus 75 +/- 15%, p = 0.01), hemorrhage (97 +/- 3% versus 44 +/- 17%, p = 0.002), valve-related morbidity (74 +/- 9% versus 42 +/- 16%, p = 0.043), and valve-related morbidity and mortality (69 +/- 9% versus 37 +/- 14%, p = 0.037) at three years. Linearized rates of hemorrhage (21 versus 2%/pt-yr; p = 0.005), valve-related morbidity (36 versus 12%/pt-yr; p = 0.02) and valve-related morbidity and mortality (50 versus 17%/pt-yr; p = 0.008) were all significantly higher in the mechanical valve group. CONCLUSION: Dialysis patients had poor survival; prosthetic valve degeneration was negligible. Incidences of thromboembolism, bleeding and valve-related morbidity and mortality were higher with mechanical valves. Linearized, as opposed to actuarial, analysis further accentuated the unacceptably high rates of complications and death with mechanical valves.     

The Mosaic bioprosthesis in the aortic position at five years

BACKGROUND AND AIM OF THE STUDY: The study aim was to collect intermediate-term data on the Mosaic bioprosthesis implanted in the aortic position. The device has been in clinical use since February 1994. METHODS: The Mosaic bioprosthesis is a stented porcine aortic valve, which combines a zero pressure differential fixation technique and anti-mineralization treatment with amino oleic acid for improved tissue durability. Between February 1994 and May 1999, 100 patients (49 females, 51 males; mean age at implant 73.4 +/- 7.3 years (range: 31-87 years) underwent aortic valve replacement with the Mosaic prosthesis in our department. Concomitant procedures were performed in 40% of cases. Patients were followed up prospectively at annual intervals; the mean follow up was 2.7 years (total 273.7 patient-years (pt-yr)) and was 100% complete. RESULTS: Total early mortality (within 30 days) was 3.0%; the late mortality rate was 4.4%/pt-yr and included a valve-related mortality rate of 0.7%/pt-yr. The freedom from event rates at five years were 97.3 +/- 1.9% for permanent neurological, 99.0 +/- 1.0% for transient neurological, 95.9 +/- 3.2 for thrombosed prosthesis, 95.6 +/- 2.2% for anti-thromboembolic-related hemorrhage, 100% for primary valvular leak, 96.9 +/- 3.0% for non-structural dysfunction, 100% for endocarditis, and 92.0 +/- 4.9% for explant. The mean systolic gradients were 15.2, 13.1 and 10.1 mmHg for the 21, 23 and 25 mm valve sizes, respectively. CONCLUSION: The clinical and hemodynamic performance of the Mosaic prosthesis was highly satisfactory during the first five years after clinical introduction. Further data will be necessary to confirm long-term durability.     

Results of heart valve replacement with the SORIN prosthesis

From March 1977 to December 1981, 872 patients at our institution underwent valve replacement with a pyrolytic carbon tilting disc prosthesis manufactured in Italy by SORIN-Biomedica. To verify the performance characteristics of this prosthesis, we analyzed the intermediate-term results obtained over a cumulative total of 3,041 patient-years (pt-yr) of follow-up. Three hundred sixty-nine patients underwent mitral valve replacement (MVR), 309 had aortic valve replacement (AVR), and 194 had both mitral and aortic (double) valve replacement (DVR). Expressed in actuarial terms (% [+/- standard error of the mean] free of adverse events at 5 years) and in linearized terms (% pt-yr), respectively, valve-related complications occurred at the following rates: Thromboembolism, 89.9 +/- 1.9% and 2.1 +/- 0.4% pt-yr (MVR); 92.1 +/- 1.9% and 1.7 +/- 0.4% (AVR); 90.5 +/- 5.0% and 2.2 +/- 0.6% (DVR). Anticoagulant-related hemorrhage, 95.2 +/- 1.5% and 1.4 +/- 0.3% (MVR); 95.9 +/- 1.5% and 1.3 +/- 0.3% (AVR); 96.0 +/- 2.0% and 0.9 +/- 0.4% (DVR). Prosthetic valve endocarditis, 99.0 +/- 0.6% and 0.2 +/- 0.1% (MVR); 97.4 +/- 1.0% and 0.6 +/- 0.2% (AVR); 94.5 +/- 1.7% and 1.4 +/- 0.4% (DVR). Reoperation, 92.6 +/- 1.5% and 1.7 +/- 0.3% (MVR); 89.4 +/- 1.9% and 2.4 +/- 0.4% (AVR); 82.3 +/- 2.9% and 4.8 +/- 0.8% (DVR). The total valve-related morbidity and mortality was 79.6 +/- 2.6% and 4.9 +/- 0.6% (MVR); 79.7 +/- 2.6% and 5.1 +/- 0.6% (AVR); 70.5 +/- 4.0% and 7.7 +/- 1.1% (DVR). The 5-year actuarial survival rate without hospital mortality was 86.8 +/- 2.0% (MVR), 91.0 +/- 1.7% (AVR), and 78.8 +/- 3.7% (DVR). The intermediate-term survival and complication rates showed the performance of the SORIN prosthesis to be quite satisfactory.     

Simultaneous aortic and mitral valve replacement: predictors of adverse outcome

BACKGROUND AND AIM OF THE STUDY: Uncertainties remain regarding the influence of several preoperative and intraoperative factors on outcome after double (simultaneous aortic and mitral) valve replacement (DVR). METHODS: Between 1981 and 1999, 132 patients (58 males, 74 females; mean age 53.8 years) underwent DVR with either aortic and mitral bileaflet mechanical valves in 81 patients, aortic tilting disk valve and mitral bileaflet valve in 36, and aortic tilting disk and mitral biological valve in 15. The mean duration of follow up was 7.6 years; cumulative follow up was 860 patient-years (pt-yr). RESULTS: Early mortality was 9.9% (n = 13). Late death occurred in 21 patients (linearized rate 2.4%/pt-yr; freedom rate at 10 years 77.6 +/- 5.4%) including cardiac-related death in 16 patients (linearized rate 1.9%/pt-yr; freedom rate at 10 years 86.9 +/- 4.5%) and valve-related death in 11 (linearized rate 1.3%/pt-yr; freedom rate at 10 years 87.7 +/- 4.3%). Late morbidity included 30 cases of thromboembolism (linearized rate 3.5%/pt-yr; freedom rate at 10 years 70.2 +/- 6.1%), seven bleeding (linearized rate 0.8%/pt-yr; freedom rate at 10 years 95.6 +/- 2.2%), 22 reoperations (linearized rate 2.6%/pt-yr; freedom rate at 10 years 79.4 +/- 5.1%), three prosthetic valve endocarditis, 13 structural valve deterioration, and two paravalvular leakage. Independent determinants of early and late mortality and morbidity, except for valve reoperation, were preoperative patient-related factors of NYHA class IV, left ventricular ejection fraction < or = 40%, mean right atrial pressure > or = 15 mmHg, and mean pulmonary artery wedge pressure > or = 25 mmHg. However, late valve reoperation and all valve-related complications were influenced by a valve-related factor, namely mitral bioprosthesis. CONCLUSION: Earlier surgical management before the development of severe heart failure, myocardial dysfunction and hemodynamic deterioration would improve the results of DVR. Mitral bioprosthesis combined with a mechanical aortic valve should be avoided as it increases the risk of reoperation.     

Mid-term results of valve replacement with the ATS valve: a seven-year follow up

BACKGROUND AND AIM of the study: The ATS open pivot bileaflet valve has been the prosthesis of choice at the authors' hospital since 1997. Herein is presented a retrospective analysis of the mid-term results of valve replacement with the ATS valve prosthesis. METHODS: Between 1997 and 2005, a total of 280 patients (mean age 58.3 years) underwent valve replacement with the ATS valve; these included 133 aortic valve replacements (AVR), 115 mitral valve replacements (MVR), and 32 double (aortic plus mitral) valve replacements (DVR). Preoperatively, 162 patients (57.9%) were in NYHA functional class II, 97 (34.6%) in class III, 19 (6.8%) in class IV, and two (0.7%) in class V. Atrial fibrillation was detected in 105 patients (37.5%), and significant coronary artery disease was found concomitantly in 13 (4.6%). Postoperative anticoagulant therapy consisting of warfarin and an antiplatelet drug was usually instituted on the first postoperative day, and the International Normalized Ratio maintained between 1.6 and 2.5. RESULTS: Overall hospital mortality was 3.6% (n = 10). Hospital survivors were followed for a mean period of 4.2 years (maximum 10 years); the total follow up was 1,127.9 patient-years (pt-yr). Follow up was complete for 267 patients (98.9%). Actuarial survival at seven years was 87.1% for AVR, 79.8% for MVR, and 90.1% for DVR. The probability of freedom from valve-related death at seven years was 96.7% for AVR, 94.4% for MVR, and 100% for DVR. The linearized rates for postoperative complications were thromboembolism 1.2%/pt-yr, major bleeding 0.7%/pt-yr, prosthetic valve endocarditis 0.2%/pt-yr, non-structural dysfunction 0.7%/pt-yr, and reoperation 0.5%/pt-yr. Structural valve failure was not encountered. CONCLUSION: This clinical experience with the ATS open pivot heart valve demonstrated low rates of adverse events and valve-related complications.     

Clinical experience of 473 patients with the omnicarbon prosthetic heart valve

BACKGROUND AND AIM OF THE STUDY: The long-term clinical experience of patients receiving Omnicarbon heart valve prostheses between January 1985 and December 1996 was investigated. METHODS: In total, 473 patients (255 males, 218 females; mean age 57.5 +/- 10.1 years (range: 20n-73 years) received 523 prostheses. These included 253 mitral (MVR), 170 atrial (AVR) and 50 double (DVR) valve replacements. RESULTS: The 30-day mortality rate was 4.7% (n = 22); in addition eight patients died more than 30 days after surgery, but during the same hospital stay. Mean follow up was 3.9 years (maximum 11 years and 7 months). Cumulative follow up was 1,750.1 patient-years (pt-yr); follow up was 97.5% complete. Among 39 late deaths, 20 were valve-related (seven cerebral infarction, seven cerebral bleeding, six endocarditis) and four cardiac-related. The overall five-year cumulative survival rate (excluding early mortality) was 90.2 +/- 11.7% (MVR 88.0 +/- 2.5%, AVR 93.1 +/- 2.3%, DVR 93.7 +/- 4.8%). At 10 years, the overall survival rate was 76.4 +/- 7.7%. Valve-related complications included thromboembolism (n = 13, 0.7%/pt-yr), anticoagulation-related hemorrhage (n = 12, 0.7%/pt-yr) and endocarditis (n = 7, 0.4%/pt-yr). Neither mechanical failure nor clinical hemolysis was observed. The overall valve-related event-free rate after five years was 89.3 +/- 2.0% (MVR 89.8 +/- 2.4%, AVR 93.5 +/- 2.6%, DVR 89.4 +/- 5.7%) and after 10 years it was 87.6 +/- 2.6% (MVR 85.4 +/- 3.7%, AVR 93.5 +/- 2.6%, DVR 82.5 +/-10.1%). CONCLUSIONS: These long-term results with the Omnicarbon valve are excellent; especially satisfactory results were achieved in terms of the low rate of thromboembolic complication.     

Low-dose oral anticoagulation and antiplatelet therapy with St. Jude Medical heart valve prosthesis

BACKGROUND AND AIM OF THE STUDY: Since 1986, the St. Jude Medical (SJM) mechanical heart valve prosthesis has been implanted in patients at the authors' institution. We present our experience of low-dose oral anticoagulation and antiplatelet therapy following SJM valve implantation. METHODS: Among 2,585 patients (mean age 40.3 +/- 13.5 years) living in a rural environment, 865 underwent aortic valve replacement (AVR), 1,231 mitral valve replacement (MVR) and 489 double valve replacement (DVR). All patients received 2.5 mg/day warfarin and a combination of antiaggregation therapy (dypridamole 3 x 75 mg/day plus aspirin 100 mg/day), irrespective of their prothrombin time and cardiac rhythm. RESULTS: Postoperatively, 139 adverse events occurred (51 in AVR patients, 58 in MVR, 30 in DVR). Operative mortality rate was 5.9%, 4.7% and 6.1%, respectively, in the three groups (overall mortality rate 5.4%). The most frequent cause of operative mortality was low cardiac output. During follow up, there were 88 anticoagulant hemorrhages (1.2%/patient-year (pt-yr)), 11 paravalvular leaks (0.2%/pt-yr), 52 thromboembolisms (0.7%/pt-yr), 60 mechanical valve thromboses (0.8%/pt-yr) and 78 reoperations (1.1%/pt-yr). These complications occurred in 101 patients after AVR, in 125 after MVR, and in 63 after DVR (4.2%, 3.7% and 4.6% per pt-yr, respectively). Patient age (p = 0.0004), concomitant surgery (p = 0.0017) and late valve-related complications (p = 0.0159) were statistically significant mortality factors after AVR. Previous surgery was a significant risk factor for operative mortality after MVR (p <0.05). Female gender (p = 0.0059) and age (p = 0.017) were significant risk factors for operative mortality after DVR (p <0.01). CONCLUSIONS: Following implantation of the St. Jude Medical mechanical heart valve prosthesis, a fixed dose of 2.5 mg/day warfarin and combined dipyridamole/aspirin provided satisfactory results in terms of thrombosis, embolism and bleeding.     

Chitra heart valve: results of a multicenter clinical study

BACKGROUND AND AIM OF THE STUDY: The Chitra tilting disc valve was developed in India to meet the need for a low-cost cardiac valve. The valve has an integrally machined cobalt-based alloy cage, an ultra-high molecular-weight polyethylene disc, and a polyester suture ring. An important feature of this valve is its soft closing sound, by virtue of a plastic occluder. METHODS: Between December 1990 and January 1995, 306 patients underwent isolated aortic (AVR, n = 101) or mitral valve replacement (MVR, n = 205) at six institutions in India. The early mortality rate was 6.9% (seven after AVR; 14 after MVR). A total of 285 survivors was followed up until September 1998; total follow up was 1212 patient-years (pt-yr) (AVR, 445 pt-yr; MVR, 767 pt-yr). RESULTS: There were 52 late deaths (4.3%/pt-yr; AVR 2.2%/pt-yr; MVR 5.5%/pt-yr). Thirty-five deaths were valve-related (23 were due to unknown causes). One AVR patient (0.2%/pt-yr) and 12 MVR patients (1.6%/pt-yr) developed valve thrombosis, and embolic episodes occurred in 25 patients (seven after AVR, 1.6%/pt-yr; 18 after MVR, 2.4%/pt-yr). Bleeding events and infectious endocarditis occurred infrequently (AVR 0.9 and 0.7%/pt-yr; MVR 0.4 and 0.5%/pt-yr, respectively). There was no incidence of paravalvular leak or structural dysfunction of the valve. Actuarial survival rates at seven years were 82.4+/-4.0% for AVR and 65.2+/-5.0% for MVR. During the same interval, thrombus-free and embolism-free survival after AVR and MVR occurred in 98.9+/-1.1% and 94.1+/-1.9%, and 92.3+/-2.8% and 82.1+/-5.7% of patients, respectively. Freedom from all valve-related mortality and morbidity at seven years was 81.5+/-4.1% after AVR, and 64.2+/-5.1% after MVR. CONCLUSION: The Chitra valve appears to be safe and to have performance comparable with that of other currently used tilting disc valves. This valve costs substantially less than other valves, and is therefore within reach of a larger subset of Indian patients.     

Single-center outcome analysis of 1,161 patients with St. Jude medical and ATS open pivot mechanical heart valves

BACKGROUND AND AIM OF THE STUDY: The clinical performance of mechanical heart valves and valve-related complications are important safety endpoints in patients after heart valve replacement. In this retrospective analysis, the mid- to long-term clinical outcomes of two similar bileaflet heart valves, routinely implanted at the authors' institution over an 11-year period, were compared. METHODS: Between January 1993 and December 2003, a total of 1,161 patients (758 males, 403 females) received either a St. Jude Medical (SJM) or ATS mechanical heart valve. Follow up was obtained via an in-house Quality Management Database, ascertained by telephone questionnaire of the patients and/or family physicians. Follow up was 98.9% complete; the median follow up was 4.6 years; total follow up was 5,624 patient-years (pt-yr). RESULTS: A total of 604 SJM and 601 ATS prostheses was implanted as isolated (n = 669) or combined (n = 492) procedures. The overall 30-day mortality for SJM and ATS was 4.1% and 3.4%, respectively (p = 0.45). Cumulative survival and freedom from valve-related mortality at 10 years for SJM and ATS valves were 66 +/- 3% versus 68 +/- 5% (p = 0.84) and 96 +/- 1% versus 97 +/- 1% (p = 0.36), respectively. No structural valve failure was encountered for both valve types. Freedom from overall valve-related complications at 10 years was 79 +/- 4% for SJM and 66 +/- 6% for ATS (p = 0.08). The linearized rates for valve-related adverse events for SJM and ATS valves, respectively, were: thromboembolism 0.9 and 1.1%/pt-yr; major bleeding requiring transfusion 0.3 and 0.5%/pt-yr; prosthetic endocarditis 0.03 and 0.1%/pt-yr; paravalvular leak 0.1 and 0.6%/pt-yr. CONCLUSION: On the basis of an 11-year experience, both bileaflet valves showed very good clinical results, with low incidences of adverse events during the mid-term outcome. Gender and/or concomitant coronary artery disease were not predictors for reduced life expectancy.     

The St. Jude Medical cardiac valve prosthesis: long-term follow up of patients having double valve replacement

BACKGROUND AND AIM OF THE STUDY: Between October 1977 and February 2002, a total of 343 patients (mean age 62 +/- 13 years; range: 19-91 years) underwent double valve replacement (DVR) with the St. Jude Medical (SJM) heart valve. Among the replacements, 337 (98%) were aortic and mitral in nature. Concomitant coronary artery bypass was performed in 73 patients (21%). METHODS: Cardiac Surgical Associates has maintained an independent database of patients undergoing valve replacement with the SJM prosthesis since the valve's first implantation in October 1977. Patients were contacted by questionnaire and/or telephone (94% complete) between November 2002 and June 2003. The patients' hospital course and valve-related events were verified by patient chart review and/or physician contact. RESULTS: Operative mortality was 8% (n = 29); mortality was valve-related in two cases. The mean follow up was 6.5 +/- 6.0 years (range: 1 month to 24 years); total follow up was 2,226 patient-years. Over 25 years, patient freedom from late mortality was 62%, and from valve-related mortality 78%. Freedom from thromboembolic events was 82% (93% from permanent defect), from bleeding events 76%, from endocarditis 98%, from valve thrombosis 99.9%, and from reoperation 98%. Six reoperations were carried out in five patients (2%), valve repair or replacement in five (2%), and suture closure of paravalvular leak in one patient (0.3%). There were no valve structural failures reported. CONCLUSION: The SJM valve has proven to be an effective and durable heart valve prosthesis. Over the long-term, the event rate is low and there is excellent freedom from reoperation in the double valve configuration.     

Fifteen years follow up with the St. Jude Medical Biocor porcine bioprosthesis

BACKGROUND AND AIM OF STUDY: The study aim was to review the 15-year results of aortic (AVR) and mitral (MVR) valve replacement with the St. Jude Medical Biocor porcine prosthesis, in order to investigate long-term survival and valve-related complications. METHODS: Between January 1983 and January 1998, a total of 1,187 patients underwent either AVR (n = 1,029; mean age 69 years) or MVR (n = 158; mean age 63 years). Follow up (99.7% complete) was monitored in 1998, and all data were analyzed with regard to actuarial valve failure rates. Long-term echocardiographic data were obtained. RESULTS: Cumulative follow up time was 5,049 patient-years (pt-yr) for AVR patients, and 845 pt-yr for MVR patients. Actuarial survival rate at 15 years was 41 +/- 3%, and freedom from valve-related death was 94 +/- 1% for the AVR group; corresponding values for the MVR group were 25 +/- 11% and 84 +/- 6%. The occurrence of structural valve deterioration (SVD) varied with age; older patients were less affected. Freedom from SVD was 76 +/- 7% and 92 +/- 4% for AVR and MVR patients, respectively. Thromboembolism (TE) occurred mainly among the oldest patients, and was most prevalent among those with MVR. Actuarial freedom from TE was 82 +/- 5% after AVR and 75 +/- 7% after MVR. Prosthetic valve endocarditis (PVE) was rare, but caused the only reoperative mortality. Freedom from PVE was 95 +/- 2% after AVR and 93 +/- 3% after MVR. CONCLUSION: Although the optimal valve substitute remains to be found, this long-term study of a third-generation bioprosthesis showed a low incidence of valve-related complications, especially of valve deterioration. This type of bioprosthesis appears to be more durable than valves of previous generations.     

CarboMedics and Monostrut valves: clinical and hemodynamic outcomes in a randomized study

BACKGROUND AND AIM OF THE STUDY: Our aim was to compare the CarboMedics (CM) and Monostrut (M) mechanical heart valve prostheses in the aortic position. These prostheses have been studied extensively in the past, both have well-defined characteristics, and have not been modified for many years. METHODS: This randomized, prospective study included 200 consecutive patients; 100 received the CM prosthesis and 100 the M prosthesis. Both groups were statistically similar in terms of age, aortic valve lesion, and preoperative clinical and surgical characteristics. Mean follow up was 5.58 years (range: 2 months to 11 years); total follow up was 1095 patient-years (pt-yr) (CM 5.33 years, 528 pt-yr; M 5.85 years, 567 pt-yr). RESULTS: Early mortality rates were 1% in the CM group and 3% in the M group. Late mortality rates were 7% and 9%, respectively. Mean (+/- SD) survival rates at 11 years were 80.51 +/- 7.36% for the CM group and 79.62 +/- 5.59% for the M group. There were no cases of mechanical valve failure in either group. The linearized rates of major thromboembolism were 1.03% and 0.20% per pt-yr for the CM and M groups, respectively; the rates of major bleeding-events were 0.71% and 0.61% per pt-yr, respectively. The rate of paravalvular leak was 0.35% and 0% per pt-yr in the CM and M groups, respectively. Postoperative NYHA class was I-II in 95.83% of CM patients, and in 94.37% of M patients. CONCLUSION: Clinical results with CarboMedics and Monostrut prostheses are highly satisfactory, but no superiority of one valve over the other can be identified.