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.     

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.     

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.     

Early and late survival following replacement of prosthetic heart valves

From May 1975 to December 1988, 62 patients underwent 66 replacements of prosthetic heart valves, due to structural valve failure in 37, prosthetic valve endocarditis (PVE) in 17, periprosthetic leak in 5, thrombosed valve in 3, hemolysis in 2, and prophylactic removal in 2. Before reoperation, 3 patients were in NYHA Class I, 24 in Class II, 21 in Class III, and 18 in Class IV. Replacements of valve prostheses were at the mitral position in 33 patients, at the aortic position in 16, at the aortic and mitral position in 9, at the mitral and tricuspid position in 5, at the tricuspid position in 2, and at the pulmonary position in 1. There were 6 early deaths (9.1%), and 13 late deaths (7.2 +/- 0.4%/patient-year). Clinical improvement of the current survivors was good. The follow-up duration was 4 months to 11.4 years (mean 3.5 years), and the cumulative follow-up was 180 patient-years (100% complete). Patients undergoing replacement of 2 prostheses showed a higher early mortality rate (35.7%) than those who received replacement of 1 prosthesis (1.9%) (p less than 0.01). The actuarial survival including early deaths was compared using the generalized Wilcoxon test. Survival was better in patients with replacement of one prosthesis than in those with replacement of 2 prostheses (p less than 0.001), and was better in NYHA Class I to III patients than in Class IV patients (p less than 0.05). Replacement of 1 prosthesis for patients with primary tissue failure of bioprostheses showed no operative mortality and a good 5 year survival rate (96 +/- 4%). High risk factors for replacement of prosthetic valves included double valve replacement, NYHA Class IV and PVE.     

Six year clinical study of use of the Omniscience valve prosthesis in 219 patients

A 6 year experience of cardiac valve replacement with the Omniscience prosthesis is described. A total of 253 valves were inserted in 219 patients. The survivors were followed up for a total of 536 patient-years and for a mean of 2.8 years. The follow-up was 97.6% complete. Analyses were performed in accordance with recommended criteria regarding definitions of complications and grading thromboembolic events for severity and analysis of anticoagulant status. Results are described both in terms of actuarial and linearized rates. For the patients at risk, actuarial survival at the end of 5 years was 87.9 +/- 3.1% overall, 90.4 +/- 3.0% for single valve (aortic 88 +/- 5%, mitral 93.3 +/- 4%) replacement and 71 +/- 11% for multiple valve replacement. The actuarial rates of freedom from complications were as follows: endocarditis 95.7 +/- 1.8% (aortic 94 +/- 3.5%, mitral 100%), periprosthetic leak 98 +/- 1% (aortic 96.2 +/- 2.6%, mitral 100%), thromboembolism 95.2 +/- 2.3% (aortic 90.9 +/- 4.6%, mitral 96.7 +/- 3.3%), valve thrombosis 98.7 +/- 0.9% (aortic 100%, mitral 100%), anticoagulant-induced bleeding 90.3 +/- 2.6% and all valve-related complications 79.4 +/- 3.6% (aortic 78.8 +/- 3.6%, mitral 85.9 +/- 4.5%). The functional improvement in patients was very satisfactory and the risk of reoperation was 1.1% per patient-year. Over a 6 year time frame, the Omniscience valve has given excellent clinical performance.     

Short- and mean results of mitral and aortic valve replacement with a Bj?rk-Shiley disc prosthesis. Thromboembolic and hemorrhagic complications]

96 patients with a Bj?rk aortic valve and 112 patients with a Bj?rk mitral valve were followed up for four and a half years and five years after operation respectively. The actuarial survival rate was 82.5% in the aortic and 73% in the mitral patients. Late death was observed in 7.3% of mitral patients with thromboembolic complications and 4.2% of mitral patients with left ventricular dysfunction, compared to 2.6% of aortic patients with thromboembolism and 3.6% with left ventricular dysfunction. The incidence of thrombolic complications was three times as great with the prosthesis in the mitral position. The probability of absence of thromboembolic complications, studied by actuarial methods, was 93% at 4 1/2 years in aortic prostheses compared to 82% at 5 years in the mitral prostheses. 12 haemorrhagic complications (5.7%), with one fatality, were observed. Aortic valve replacement with a Bj?rk prosthesis is a very satisfactory operation and the results compare favourably with other prostheses. However, the risk of thromboembolic complications should be seriously considered in the surgical indications when this prosthesis is to be used for mitral valve replacement.     

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.     

The Mitroflow bioprosthesis. Results after 6 years

From March 1982 through December 1986, 139 Mitroflow pericardial heart valves were utilized in 129 patients. There were 69 males and 60 females, with an average age of 55.2 years (range 26 to 74 years). Eighty-nine patients underwent isolated aortic valve replacement, 27 isolated mitral valve replacement, three isolated tricuspid valve replacement and ten mitral-aortic valve replacement. In 20.9% additional cardiac surgery was performed. Maximum follow-up was 6 years with a mean of 43.9 months. The cumulative follow-up was 491 patients/year. Overall hospital mortality was 1.6% (2 cases). There were 3 late deaths in this series (2.4%). The linearized incidence of late mortality was 0.49% per patient/year. The survival actuarial curve was 96% +/- 1.8. The incidence of thromboembolism was 1.22% per patient/year, and the actuarial thromboembolism-free rate was 93% +/- 2.7. Three patients developed primary tissue failure of the Mitroflow valve in the mitral position. The linearized incidence of primary tissue failure was 0.73% per patient-year and the actuarial freedom from primary tissue failure was 95% +/- 3.2%. A total of 4 patients underwent reoperation (0.49% per patient/year). In conclusion, the clinical performance of the Mitroflow pericardial heart valve at medium-term follow-up is satisfactory; however a significant number of early primary tissue failures have already occurred in the mitral position.     

Carpentier-Edwards porcine bioprostheses: clinical performance assessed by actual analysis

BACKGROUND AND AIM OF THE STUDY: The clinical performance of porcine bioprostheses for valve replacement has been evaluated for over three decades by actuarial analysis as the standard for reporting time-related results. Actual or cumulative incidence analysis provides a complementary method to determine the manifestations of valve-related complications due primarily to structural valve deterioration. Valve-related mortality and reoperation of porcine bioprostheses for aortic and mitral valve replacement was compared by actuarial and actual methodology. METHODS: The Carpentier-Edwards porcine bioprostheses were implanted between 1975 and 1995 as 2,237 aortic valve replacements (AVR) and 1,582 mitral valve replacements (MVR). Coronary artery bypass was performed in 36.4% of AVR, and 30.6% of MVR. Fatal valve-related complications occurred in 7.6% of AVR and 11.3% of MVR. The cumulative follow up was 14,810 patient-years (mean 6.6 years) for AVR and 9,718 patient-years (mean 6.1 years) for MVR. RESULTS: Patient survival, and actuarial and actual freedom from valve-related mortality and valve-related reoperation was reported at 15 years. For AVR, survival in the 61-70 years age group was 30.9%, freedom from valve-related mortality was 79.3% and 86.9% respectively, and freedom from valve-related reoperation 79.0% and 88.1% respectively. For AVR, survival in the >70 years age group was 18.1%, freedom from valve-related mortality 72.8% and 84.9% respectively, and freedom from reoperation 86.3% and 96.1% respectively. For MVR, survival in the 61-70 years age group was 16.1% at 15 years, freedom from valve-related mortality was 59.5% and 79.5% respectively, and freedom from valve-related reoperation 32.6% and 71.0% respectively. For MVR, survival in the >70 years age group was 2.8% at 15 years, valve-related mortality was 26.1% and 82.0% respectively, and freedom from valve-related reoperation 83.4% and 93.3% respectively. CONCLUSION: The actual freedom from valve-related mortality and valve-related reoperation (primarily from structural valve deterioration), provides further evidence to consider porcine bioprostheses for AVR in patients aged >60 years, and for MVR in patients aged >70 years. The freedom from valve-related mortality supports the use of porcine bioprostheses for MVR in patients aged 61-70 years. Patient survival is influenced to the greatest extent by factors other than valve-related mortality.     

Evaluation of the Sorin bicarbon bileaflet valve in 488 patients (519 prostheses)

The Sorin bicarbon bileaflet prosthesis was introduced in 1990. To evaluate the clinical performance of this prosthesis, we reviewed 519 prostheses that were implanted in 488 patients (275 men, 213 women; mean age 59 years; SD 10.8, range 19 to 88) from 1993 to 1997. Preoperatively, 82% of patients were in New York Heart Association (NYHA) functional class III or IV. There were 263 aortic valve replacements (AVRs) (54%), 194 mitral valve replacements (MVRs) (40%), and 31 AVRs and MVRs (both) (6%). Concomitant procedures were performed in 82 patients (17%). Follow-up was complete in 471 (97%) with a total cumulative follow-up of 866 patient-years. The 30-day mortality for patients with AVR was 5.7% (95% confidence interval [CI] 2.9 to 8.5), MVR 17.5% (CI 9.9 to 19.7), and both 19% (CI 7.6 to 51.1), with no early valve-related deaths. Patient survival at 55 months was 76% (SE 2.27%), with patients with AVR being 90%, MVR 63%, and both 61%. This was influenced by the following: (1) valve position, which was higher for MVR (p = 0.0001); (2) poor NYHA functional class (p = 0.0006); (3) reoperation (p = 0.02); and (4) age >70 years (p = 0.0001). Valve-related complications (expressed as percentage per patient year and number of events) were major thromboembolism at 0.9% per year (8), with AVR rates being 1.2% per year (6) and MVR 0.7% per year (2); major hemorrhage at 2.3% per year (20) with AVR rates being 2.4% per year (12) and MVR 2.5% per year (7); bacterial endocarditis at 0.2% per year (2); and nonstructural dysfunction rate of 0.7% per year (6). The reoperation rate was 0.9% per year (8) with AVR being 0.6% per year (3) and MVR 1.7% per year (5). At 55 months, actuarial freedom from major thromboembolism was 97% (SE 1.1%) with AVR being 96% and MVR 98%; major hemorrhage 89% (SE 3.1%) with AVR being 88.6% and MVR 91%; structural valve dysfunction 100% (SE 0.0%); and reoperation 97.1% (SE 1.10%) with AVR being 98.5% and MVR 94.6%. At follow-up, 88% of survivors were in NYHA class I or II. In this series, hospital mortality and overall survival in patients were influenced by the patients' clinical characteristics. There were no early valve-related deaths. Valve-related complications were similar to previously reported series with no episode of structural failure. Our experience with the Sorin bicarbon bileaflet prosthesis suggests that it has a satisfactory clinical performance, with low complication rates.     

Evaluation of valve-related complications in patients with Sorin Bicarbon prosthesis: a seven-year experience.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the medium-term results of aortic valve replacement (AVR), mitral valve replacement (MVR) and double valve replacement (DVR) with the Sorin Bicarbon prosthesis. METHODS: A total of 990 patients (568 men, 422 women; mean age 60+/-10 years; range: 20-86 years) was reviewed who received 1,108 Sorin Bicarbon prostheses between 1992 and 1998 at three institutions. AVR was performed in 541 patients (55%), MVR in 330 (33%) and DVR in 119 (12%). Concomitant procedures, mainly coronary artery grafting, were performed in 222 patients (22%). Follow up was 98% complete; total cumulative follow up was 3,091 patient-years. RESULTS: Hospital mortality was 3.7% (n = 37). There were 49 late deaths; actuarial survival at seven years was 88+/-2% after AVR, 86+/-5% after MVR, and 78+/-8% after DVR. At last follow up, 915 survivors were in NYHA functional class I or II. At seven years, actuarial freedom from valve-related deaths, valve thrombosis, embolism and bleeding respectively was 96+/-1%, 99+/-1%, 93+/-2% and 91+/-3% after AVR; 97+/-2%, 97+/-3%, 90+/-3% and 86+/-7% after MVR; and 92+/-6%, 98+/-1%, 64+/-2% and 82+/-2% after DVR. Reoperation was required in 20 patients (due to valve thrombosis in six, endocarditis in five and periprosthetic leak in nine). At seven years, actuarial freedom from reoperation was 97+/-1%, 96+/-2% and 84+/-9% after AVR, MVR and DVR, respectively; actuarial freedom from endocarditis was 99+/-1%, 99+/-1% and 95+/-5%. Nine patients experienced a nonstructural valve dysfunction (all periprosthetic leak), while no cases of structural failure were observed. CONCLUSION: The Sorin Bicarbon prosthesis has shown good medium-term results with regard to clinical improvement, and low incidence of valve-related complications. Thus, it appears to be a reliable valve substitute when the use of a mechanical prosthesis is indicated.     

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 St. Jude medical valve: early clinical results in 253 patients

The St. Jude Medical cardiac valve is a low-profile, bileaflet, central-flow prosthesis made entirely of pyrolytic carbon. A total of 261 St. Jude valves were implanted in 253 patients during a 25-month period. Perioperative mortality for the entire series was 9.1%, including patients undergoing reoperation for valve disease and those having associated cardiac procedures. There were four nonfatal thromboembolic episodes during the follow-up period, resulting in a risk of thromboembolism for aortic and mitral valves of 2.1% and 2.1% per patient year, respectively. There were no instances of structural failure of the valve, and no valve-related hemolysis occurred. Two-year actuarial survival was 95%. Hemodynamic studies indicate that the valve has the lowest transvalvular pressure gradient of any prosthetic mechanical valve available, and we believe it is the valve of choice for patients in whom a prosthetic mechanical valve is indicated.     

Performance of bioprostheses and mechanical prostheses in age group 61-70 years

BACKGROUND AND AIM OF THE STUDY: The performance of bioprostheses (BP) and mechanical prostheses (MP) from valve-related composites of complications and combined major thromboembolism and hemorrhage were considered in order to facilitate decision-making for the patient age group of 61-70 years. METHODS: The aortic valve replacement (AVR) population (BP, n = 619; MP, n = 303) was differentiated by age, concomitant coronary artery bypass, diabetes mellitus, chronic obstructive pulmonary disease (COPD) and preoperative renal failure. The mitral valve replacement (MVR) population (BP, n = 353; MP, n = 312) was differentiated by valve type, age, concomitant coronary artery bypass, ejection fraction, NYHA and preoperative renal failure. RESULTS: Actual freedom from reoperation for AVR was 92.1 +/- 1.5% for BP and 98.7 +/- 6.6% for MP, and for MVR was 74.5 +/- 2.6% for BP and 93.8 +/- 2.2% (12 years) for MP. Actual freedom from major thromboembolism and hemorrhage for AVR was 85.1 +/- 1.7% for BP and 76.9 +/- 3.6% for MP, and for MVR was 82.7 +/- 2.4% for BP and 76.7 +/- 3.8% (12 years) for MP. Linearized rates were undifferentiated for major thromboembolism. The hemorrhage rate for AVR-BP was 0.55%/pt-yr and for AVR-MP was 2.3%/pt-yr (p < 0.0001); for MVR-BP, the rate was 0.69%/pt-yr and for MVR-MP was 1.85%/pt-yr (p = 0.0011). The only predictor of AVR reoperation was age, and predictors for MVR reoperation were prosthesis type and follow up NYHA class. Predictors of AVR major thromboembolism and hemorrhage were prosthesis type, age, diabetes mellitus and COPD. There were no predictors of MVR major thromboembolism and hemorrhage. CONCLUSION: For the age group of 61-70 years, MP are recommended for MVR to protect from BP reoperation, whilst for AVR BP are recommended to protect from anticoagulant hemorrhage. Freedom from reoperation for AVR was undifferentiated for BP and MP at 12-15 years.     

Mechanical aortic valve replacement: long-term outcomes in children

BACKGROUND AND AIM OF THE STUDY: Early and late outcomes following mechanical aortic valve replacement (AVR) in children were analyzed. METHODS: Between January 1980 and December 2003, 55 patients underwent mechanical AVR at the authors' institution. Of these patients, 12 had aortic regurgitation (AR), 31 had aortic stenosis (AS), and 12 had mixed disease. Preoperatively, 25 patients (45.5%) were in NYHA classes III and IV. Among patients, 22 had a previous valvotomy and 19 had associated cardiac defects. Isolated AVR was performed in 37 cases. Twelve patients required root enlargement procedures, two had aortic root replacement, three had a double valve replacement, and one patient had a concurrent mitral annuloplasty. The mean prosthesis size was 22.6 mm (range: 16-31 mm). Mean follow up was 12.28 +/- 6 years (range: 1-23 years); total follow up was 665 patient-years (pt-yr). RESULTS: There was one late death. Actuarial survival at 20 years was 98 +/- 2%. Event-free survival at one, five and 20 years was 96 +/- 3%, 92 +/- 4% and 88 +/- 5%, respectively. Four patients required reoperation (two for valve outgrowth, one each for paravalvular leak and prosthetic valve endocarditis (PVE)). Freedom from reintervention at one, five and 20 years was 98 +/- 2%, 96 +/- 3% and 92 +/- 4%, respectively. There was one event of anticoagulation-related hemorrhage. Freedom from anticoagulant-related hemorrhage at 20 years was 98 +/- 2%, and freedom from PVE at five and 20 years was 98 +/- 2% and 96 +/- 3%, respectively. There were no instances of thromboembolism or structural valve dysfunction. Linearized rates of bleeding and endocarditis were 0.15 and 0.3% per pt-yr, respectively. At follow up, 54 children were in NYHA classes I or II. CONCLUSION: Mechanical AVR, with aortic root enlargement if necessary, is associated with low mortality and morbidity, and is an excellent treatment option in children. Late embolic and hemorrhagic complications are infrequent in the current era.     

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.     

Clinical evaluation of the carbomedics prosthesis: experience at providence health system in Portland

BACKGROUND AND AIMS OF THE STUDY: This study details the authors' experience with the CarboMedics bileaflet mechanical prosthesis, and assesses the valve's efficacy in terms of early mortality and long-term morbidity. METHODS: Between July 1994 and December 2000, a total of 696 CarboMedics valves was implanted in 616 patients. Aortic valve replacement (AVR) was performed in 350 (57%) patients, mitral valve replacement (MVR) in 161 (26%), double (aortic + mitral) valve replacement (DVR) in 79 (13%), and other procedures in 26 (4%). RESULTS: There were 32 operative deaths. Operative mortality was 4.3% for AVR, 6.8% for MVR, and 7.6% for DVR. Linearized rates for late death were 3.4%/patient-year (pt-yr), 5.5%/pt-yr and 7.7%/pt-yr for AVR, MVR and DVR, respectively. Survival at five years was 80.1% for AVR, 73.0% for MVR, and 64.6% for DVR (p = 0.004). Freedom from reoperation at five years was 97.6% for AVR, 98.1% for MVR, and 94.1% for DVR (p = 0.718); freedom from thromboembolism at five years was 96.3% for AVR, 98.6% for MVR, and 88.3% for DVR (p = 0.04). Linearized rates of late thromboembolism were 0.7%/pt-yr, 0.4%/pt-yr and 2.3%/pt-yr, respectively. Freedom from PVE at five years was 98.4% for AVR, 97.0% for MVR, and 89.7% for the DVR group (p = 0.172). Linearized rates of PVE were 0.5%/pt-yr, 0.9%/pt-yr and 1.8%/pt-yr, respectively. Freedom from anticoagulant-related bleeding at five years was 98.0% in the AVR group, 97.8% in the MVR group, and 88.3% in the DVR group (p <0.001); linearized rates of this event were 0.4%/pt-yr, 0.6%/pt-yr and 3.2%/pt-yr, respectively. One valve thrombosis was found after MVR, and another in the mitral position after DVR. CONCLUSION: Early and intermediate-term follow up of the CarboMedics prosthesis indicates that the clinical performance of this valve is satisfactory, and results are comparable with those obtained for other mechanical valves.     

Seventeen-year experience with the St. Jude medical biocor porcine bioprosthesis

BACKGROUND AND AIM OF THE STUDY: Bioprostheses in heart surgery have been investigated in recent years to reduce the long-term anticoagulant administration associated with mechanical devices. Positive results have been achieved, particularly in elderly patients who have a supposed delayed fibrocalcification and reduced life expectancy. Herein are reported 17-year data on the ongoing long-term study of the Biocor porcine prosthetic heart valve, an improved bioprosthesis with reduced stiffness and improved flexibility of the valve cusps designed to resolve issues of reduced lifespan of previous biological valves. METHODS: Data were presented for 1,455 patients who underwent aortic valve replacement (AVR) or mitral valve replacement (MVR) in Sweden with glutaraldehyde-preserved Biocor bioprostheses between 1983 and 2000. Follow up after surgery was evaluated on alternate years using hospital records, interviews, questionnaires and the Cox regression model of multivariate analysis. RESULTS: At 17 years, the cumulative follow up was 6,540 and 989 patient-years (pt-yr) for AVR and MVR, respectively. Late mortality accounted for 357 (28%) and 65 (38%) patients, respectively, and actuarial survival was 28.2% and 35.4%, respectively. Thromboembolic events occurred in 82 AVR (1.25%/pt-yr) and 18 MVR (1.82%/pt-yr) patients, respectively, with freedom from thromboembolism decreasing with age; 181 AVR and 44 MVR patients received anticoagulants. Reoperations due to structural valve deterioration (SVD) were required in 63 AVR and nine MVR patients. Freedom from reoperation due to SVD increased with age in both groups; actuarial freedom from reoperation was 73.9% and 81.3%, respectively. CONCLUSION: Seventeen-year data confirm the low incidence of valve-related complications and improved valve durability reported at the 15-year follow up after both AVR and MVR using Biocor porcine bioprostheses.     

Perimount pericardial bioprosthesis for aortic calcified stenosis: 18-year experience with 1133 patients

BACKGROUND AND AIM OF THE STUDY: Aortic stenosis (AS) is the most important cause of aortic valve disease, its prevalence increasing with patient age. The present study formed part of a long-term evaluation on use of the Perimount pericardial valve for aortic calcified stenosis. METHODS: A total of 1133 consecutive patients who underwent aortic valve replacement (AVR) with a Perimount pericardial bioprosthesis for degenerative AS between July 1984 and December 2003 at the authors' institution, was followed up in 2004. Among the patients (716 males, 417 females; mean age 72.6 years), 997 were in sinus rhythm, and the mean NYHA functional class was 2.3. Preoperative echocardiography indicated a mean gradient of 56 mmHg, a peak gradient of 89 mmHg, and an effective orifice area of 0.6 cm2. Associated procedures were required in 336 patients. RESULTS: All patients but 18 (1.5%) were followed up for an average of 5.5 years postoperatively; thus, the total follow up was 6,180 patient-years. Operative mortality was 2.8% (n=32), and there were 330 late deaths. At 18 years the actuarial survival rate was 22 +/- 4%. Among the 725 patients followed, 80% were in sinus rhythm and 98% in NYHA classes I or II. Valve-related complications included 39 thromboembolic episodes, 24 endocarditis, 22 anticoagulant-related hemorrhage, 28 reoperations, and 19 structural valve failures. A total of 54 patients died from valve-related causes (13 embolic events, two endocarditis, two hemorrhage, one structural failure, 36 unknown causes), and 57 died from cardiac failure. Neither thrombosis nor hemolysis was observed. At 18 years, freedom from embolism was 92 +/- 2%, from endocarditis 93 +/- 4%, from hemorrhage 95 +/- 2%, from reoperation 62 +/- 11%, from valve failure 68 +/- 12%, and from all complications 47 +/- 8%. Among patients aged >60 years, the 18-year actuarial freedom from reoperation was 76 +/- 14%, and from valve failure 85 +/- 8%. CONCLUSION: With a low rate of valve-related events at 18 years, and an especially low rate of structural failure, the Perimount pericardial prosthesis is a reliable choice for patients with aortic calcified stenosis.     

Aortic valve replacement with Toronto SPV in elderly patients: 10-year results

A retrospective assessment of clinical and echocardiographic variables was performed in 145 patients who received a Toronto SPV aortic valve replacement. The majority (90%) of these elderly patients (mean age, 75.5 +/- 7.4 years) were preoperatively in New York Heart Association class III-IV. Operative mortality was 4.8%. Follow-up was complete up to 10 years and revealed few valve-related complications: thromboembolism (7), bleeding (4), and prosthesis dysfunction necessitating reoperation (3). Late mortality was cardiac-related in 11.7% and noncardiac-related in 17.2%. Actuarial survival was 83% at 5 years and 63% at 8 years. Echocardiography showed low transvalvular gradients (peak, 17.5 +/- 7.5 mm Hg; mean, 9.2 +/- 4.2 mm Hg) resulting in a significant reduction in left ventricular mass index during the first 3 years. Independent of the transprosthetic gradient, left ventricular mass index tended to increase again beyond the 5th year, which correlated positively with the presence of arterial hypertension in this older population. The Toronto SPV bioprosthesis offers an aortic valve substitute with excellent long-term hemodynamics, resulting in significant early left ventricular mass regression. Considering the limitations of this selected elderly population, the clinical outcome and survival up to 10 years are encouraging, with few observed valve-related events.