Ten-year trends in heart valve replacement operations

BACKGROUND: There has been increasing concern in recent years about the quality and cost of heart valvular replacement procedures. The purpose of this study is to examine the profile of patients undergoing valvular operations during the past decade, and to look at trends in outcome and resource utilization over that period. METHODS: Clinical and procedural data of 2,972 patients undergoing heart valve replacement at Emory University Hospitals between 1988 and 1997 were recorded prospectively on standardized forms by trained medical personnel and entered into a computerized database. RESULTS: There were 1,802 patients undergoing aortic valve replacement (AVR), 966 undergoing mitral valve replacement (MVR), and 204 undergoing combined aortic and mitral valve procedures (AVR + MVR). No patients were excluded. There was a statistically significant trend for patients undergoing AVR, MVR, or AVR + MVR over time to be older and sicker by multiple criteria. Nonetheless, procedural outcome and inhospital mortality for patients undergoing AVR remained unchanged. Cost and length of stay increased from 1988 to 1992 when a concerted effort to decrease resource utilization began. Between 1992 and 1997 for AVR, length of stay decreased from 13.4 to 8.0 days and cost from $37,047 to $21,856. Similarly, between 1992 and 1997 for MVR, length of stay decreased from 15.6 to 8.1 days and cost from $45,072 to $21,747. The net result over the time period from 1988 to 1997 was an average decline in the cost of operation of $785 a year, adjusted for other factors. CONCLUSIONS: This study reveals that outcome of valvular replacement during the period from 1988 to 1997 has remained constant despite the patients becoming older and sicker during the same period. This constant outcome has been accomplished, but length of stay has decreased significantly. Hospital costs increased during the first years of the study period, but then decreased to levels in 1997 that were equal to or significantly less than 1988 levels.     

Predictors of outcome in a multicenter port-access valve registry

BACKGROUND: The aim of this study was to examine the predictors of outcome in patients undergoing isolated valve operation using port-access techniques. METHODS: Logistic regression analysis was performed in a prospective, multi-institutional registry of patients undergoing isolated aortic valve replacement (AVR, n = 252), mitral repair (MVP, n = 491), or mitral replacement (MVR, n = 568) using port-access techniques from 1997 to 1999. RESULTS: Endoaortic balloon occlusion was used in 2% (AVR), 93% (MVP), and 90% (MVR) of cases. Conversion to full sternotomy occurred in 3.8% of all cases. For all patients, early mortality was 50 of 1,311 (3.8%) and onset of new atrial fibrillation occurred in 140 of 1,311 (11%) patients. The determinants of 30-day mortality were redo, age, and MVR or AVR. The determinants of reoperation for bleeding were age, reoperation, and MVR. Age was a predictor for stroke, and age and low or medium volume center were predictors of new atrial fibrillation. CONCLUSIONS: Excellent short-term results can be obtained using port-access techniques in isolated mitral or aortic valve operations. Patient outcome is not related to institutional case volume, and the primary determinants of outcome after port-access valve procedures are generally patient-related factors.     

Improved early results after heart valve surgery over the last decade

Objectives: This study was undertaken to investigate time trends in early mortality, morbidity and clinical characteristics of patients undergoing heart valve surgery over the last decade. Methods: A regional, prospectively collected, study comprising all patients (2327) undergoing valve surgery in a defined geographical area from January 1990 to December 1999 was conducted. Data were collected from 1746 patients submitted to aortic valve replacement (AVR), 432 to mitral valve replacement (MVR), 78 to double valve replacement (DVR) and 71 to mitral valve repairs. Logistic regression was used to identify risk factors for early mortality. Time trends of early mortality, morbidity and clinical characteristics were analysed. Results: The total early mortality rate was 5.9%; for AVR it was 4.8%, MVR 9%, DVR 14% and mitral valve repair 1.4%. The risk factor profiles for early mortality were similar in all groups of valve interventions, with shock, age over 70 years and advanced NYHA class as the strongest risk factors. There was a decrease in early mortality over the period which remained after correction for risk factors. The proportion of patients over 70 years of age and of patients with diabetes increased, whereas other risk factors were not altered during the study period. Conclusion: It is confirmed that early risks for death after heart valve surgery have decreased. This improvement was consistent after adjustment for risk factors.     

The initial experience with the ATS Medical mechanical cardiac valve prosthesis

BACKGROUND: From May 1994 through October 2000, a total of 1,146 patients underwent valve replacement with the ATS Medical mechanical cardiac valve prosthesis under a study protocol approved by international ethics committees (non-United States participants) or under a United States Food and Drug Administration-approved Investigational Device Exemption study. The study took place at 19 domestic and three international centers. METHODS: As required by the Food and Drug Administration's Heart Valve Guidance Document, only isolated implants were included in the study (double-valve implants were excluded), with operative and follow-up data collected from each center. RESULTS: Aortic valve replacement (AVR) was conducted in 801 patients (309 with coronary bypass) and mitral valve replacement (MVR) in 345 patients (78 with coronary bypass). Overall operative (< or = 30 days post implant) mortality was 2.1% (17 AVR = 2.1%, 7 MVR = 2.0%), 7 of which (AVR = 4, MVR = 3) were valve related. In 2,086 patient-years (1,459 AVR patient-years, 627 MVR patient-years) of follow-up, there were an additional 50 patient deaths of these, 18 were valve related, 9 due to anticoagulant related bleeding, 5 sudden/unexplained, and 1 each after stroke, thrombosis, prosthetic valve endocarditis, and thromboembolism. Late (>30 days post implant) valve-related complications included: transient and chronic thromboembolism (27 AVR (linearized rate 1.85%/patient-year) and 20 MVR (3.19%/patient-year), of which 11/47 (0.53%/patient-year) had chronic deficits, thrombosis (1 AVR = 0.07%/patient-year and 4 MVR = 0.64%/patient-year), paravalvular leak (10 AVR = 0.69%/patient-year and 8 MVR = 1.28%/patient-year), anticoagulant related hemorrhage (34 AVR = 2.33%/patient-year and 8 MVR = 1.28%/patient-year), prosthetic valve endocarditis (3 AVR = 0.21%/patient-year and 2 MVR = 0.32%/patient-year), and structural valve failure or dysfunction (0%). Echocardiographic gradients were proportional to valve size and did not significantly change over the follow-up period. CONCLUSIONS: This study documented the ATS Medical mechanical cardiac valve prosthesis to be a valuable addition to the surgeon's armamentarium in the treatment of cardiac valvular disease.     

Open heart surgery in the elderly

Of 3254 open heart surgical cases performed since 1972, 126 patients (3.9%) were 70 years of age or older. The mean age was 72 years, the oldest being 82. Sixty-seven per cent were male. The following procedures were performed: coronary artery bypass grafting (CABG) 51, aortic valve replacement (AVR) 44, AVR + CABG 16, mitral valve replacement (MVR) 3, MVR + CABG 6, MVR + AVR 4, and other, 2. Of those undergoing CABG, 33% came from the Coronary Care Unit and 24% had left main coronary artery stenosis. There was one peri-operative death (2.0%). Of those undergoing AVR, 43% had coronary artery disease and 13% triple vessel disease. Operative mortality for AVR, and AVR + CABG was 11.4% (5/44) and 18.8% (3/16), respectively. Twenty-six per cent of operative survivors had significant postoperative complications (excluding atrial arrhythmias). The postoperative hospital stay for CABG, AVR and other cases was 11, 13 and 16 days, respectively. Seven year survival of all patients was 61.2 +/- 6.5% (+/- 1 SE) and for AVR +/- CABG was 51.5 +/- 8.6%. Five year survival for CABG was 83.9 +/- 6.3%. We conclude that, in selected cases, CABG can be performed safely in the elderly. Although valvular and combined surgery may result in significant morbidity and mortality, the satisfactory long term results in survivors justifies surgery in this group of patients.     

Eight year experience with the CarboMedics bileaflet valvular prosthesis.

Two hundred and two patients (97 female and 105 male; mean age: 45. 5+/-9 years) received CarboMedics bileaflet valves during a period of eight years. Ninety-one patients received mitral, 72 aortic and 39 aortic+mitral valve prosthesis. Tricuspid plasty and coronary artery bypass surgery were the concomitant operations in 17 and 12 patients, respectively. The mean follow-up period was 24.7 months and the ratio was 91%. Overall operative mortality was 3.96% (8 patients); 2.78% for aortic valve replacement (AVR), 3.29% for mitral valve replacement (MVR) and 7.7% for double valve replacement (DVR). The late mortality rate was 2.89% for AVR, 2.2% for MVR and 8. 3% for DVR. The main cause of mortality was low cardiac output. The overall survival rate was 91.5% in 2 years. The actuarial freedom from thromboembolism in 2 years was 97% for AVR, 95% for MVR and 84% for DVR. No mortality due to heamorrhagic events was observed. CarboMedics prosthetic heart valves may be used satisfactorily with a low incidence of valve-related morbidity and mortality.     

Long-term clinical results after combined aortic and mitral valve replacement

The results after 282 consecutive double (aortic & mitral) valve replacements (DVR) are compared with our previously reported experience after mitral (MVR, n = 810) and aortic valve replacement (AVR, n = 1753). All but one patient received Bj?rk-Shiley valves. The follow-up which closed on August 1, 1985 was 99.3% and covered 16,869 patient-years (mean 6.3 years/patient). Autopsies were performed in 74% of all fatalities. Early mortality rates were identical in the three patient groups, and late mortality did not differ between MVR and DVR patients. The fraction of valve-related mortality was similar in all groups. Anticoagulant-related bleeding was equally common in all patient groups. The incidences of thromboembolism, reoperation and valve failure did not differ between MVR and DVR patients, but were significantly higher than among AVR patients. With the exception of a slightly increased incidence of prosthetic valve endocarditis, the results after DVR equal those after MVR. In cases with severe mitral valve disease but borderline aortic valve disease, primary DVR is clearly justified and eliminates the need for, and risks of, a secondary AVR.     

Improved in-hospital mortality in women undergoing coronary artery bypass grafting. Northern New England Cardiovascular Disease Study Group

BACKGROUND: Few studies have examined the changes in in-hospital mortality for women over time. We describe the changing case mix and mortality for women undergoing coronary artery bypass grafting (CABG) from 1987 to 1997 in northern New England. METHODS: Data were collected on 8,029 women and 21,139 men undergoing isolated CABG. The study consisted of three time periods (1987 to 1989, 1990 to 1992, and 1993 to 1997) to account for regional efforts to improve quality of care that occurred during 1990 to 1992. RESULTS: Compared with 1987 to 1989, women undergoing CABG in 1993 to 1997 were older, had poorer ventricular function, and more often required urgent or emergency operations. The crude and adjusted mortality rates for both women and men decreased significantly over time. The absolute magnitude of the change in adjusted rates was greater for women (3.1%) than for men (1.5%). Although women represented only 28% of the study population, the decrease in their mortality accounted for 44% of the total decrease in adjusted mortality during the study period. CONCLUSIONS: Over the last decade there has been a marked decrease in CABG mortality for women, despite a worsening case mix.     

Durability and low thrombogenicity of the St. Jude Medical valve at 5-year follow-up

Between November, 1978, and December, 1983, 736 patients had valve replacement with the St. Jude Medical valve prosthesis. There were 478 patients with aortic valve replacement (AVR), 188 with mitral valve replacement (MVR), 63 with double valve replacement, and 7 with tricuspid valve replacement (they were not included in this study). The mean age at the time of operation was 46.7 years for patients having AVR and 48.6 years for those having MVR and AVR + MVR. Follow-up totaled 1,116 patient-years (range, 4 to 82 months). Early (30-day) mortality was lowest for isolated MVR (2.3%) and AVR (3.7%), and increased with reoperation or when associated procedures were combined with valve replacement. Patients undergoing reoperation or having associated procedures made up 49% of the AVR and 54% of the MVR groups. All patients were advised of the need for long-term anticoagulation with warfarin sodium. Nine patients (7 with AVR, 1 with MVR, 1 with AVR + MVR) had suspected or confirmed episodes of systemic thromboembolism, a linearized incidence of 0.99% per patient-year for AVR, 0.36% per patient-year for MVR, and 0.98% per patient-year for AVR + MVR. Eight patients with AVR underwent reoperation for prosthetic valve endocarditis (5 of the 8 patients had endocarditis prior to initial valve replacement). There were no instances of structural valve failure. There were 37 late deaths. Actuarial survival at 5 years (excluding early mortality, 95% confidence limits) was 89.8% for AVR, 84.8% for MVR, and 95.2% for AVR + MVR.(ABSTRACT TRUNCATED AT 250 WORDS)     

Do hospitals with low mortality rates in coronary artery bypass also perform well in valve replacement?

BACKGROUND: While hospital performance in coronary artery bypass graft (CABG) surgery is reported widely, patients may find it difficult to learn about their hospital's performance in heart valve replacement. We sought to determine if a hospital's performance in CABG is correlated to its performance in heart valve replacement. METHODS: We studied operative mortality after CABG, aortic valve replacement (AVR), and mitral valve replacement (MVR) using the 1994 to 1999 national Medicare database. After excluding any hospital that did not perform at least 50 CABGs and 20 valve replacements per year we examined the correlation between hospital mortality in CABG and hospital mortality in AVR and MVR using least-squares simple linear regression models. Operative mortality was adjusted for patient characteristics using logistic regression models. RESULTS: A total of 684 hospitals performed 817,606 isolated CABGs, 142,488 AVRs (54% with concomitant CABG), and 61,252 MVRs (45% with concomitant CABG). Hospital mortality rates with AVR ranged from 6.0% to 13.0% between hospitals in the lowest and highest, respectively, 10th percentile of CABG performance. Similarly hospital mortality rates with MVR ranged from 10.1% to 20.5% in the lowest and highest respectively, 10th percentile of CABG performance. Adjusted mortality rates for both AVR and MVR were closely correlated with isolated CABG mortality rates (correlation coefficients 0.592 and 0.538, respectively; p = 0.001 for both correlations). In stratified analyses these correlations persisted regardless of whether valve replacement was performed with or without concomitant CABG or whether valve replacement was performed in a high- or low-volume hospital. CONCLUSIONS: Hospital mortality rates with CABG are closely correlated with mortality rates with valve replacement. These findings suggest that shared processes and systems of care are important determinants of performance in cardiac surgery.     

Midterm evaluation of the Sorin Bicarbon heart valve prosthesis: single-center experience

BACKGROUND: The purpose of this study was to perform midterm evaluation of the clinical performance of the Sorin Bicarbon mechanical heart valve prosthesis. METHODS: From November 1992 to December 2002, 328 patients underwent isolated aortic (AVR; 156) or mitral (MVR; 172) valve replacement with the Sorin Bicarbon mechanical valve. Concomitant surgery was performed in 83 patients (25.2%). RESULTS: Total hospital mortality was 5.2%. Survival at 7 years was 79.5% for AVR and 82.4% for MVR. Kaplan-Meier freedoms from valve-related complications were as follows: thromboembolism 92.7% (AVR 94.8%, MVR 92.1%); bleeding 93% (AVR 91.9%, MVR 94.5%); nonstructural dysfunction 96.6% (AVR 94.7%; MVR 97.9%); endocarditis 97.7% (AVR 97.4%, MVR 98.1%); and reoperation 95.7% (AVR 96.6%, MVR 93.9%). Overall freedom from valve-related death was 93.2% (AVR 99.3%, MVR 91.2%). At the end of follow-up, 88.9% of survivors were in New York Heart Association class I or II. CONCLUSIONS: The Sorin Bicarbon valve is a satisfactory mechanical valve prosthesis with low mortality and morbidity and good functional results.     

Five- to eight-year follow-up of patients with the Hancock cardiac bioprosthesis

All patients undergoing a heart valve replacement with a glutaraldehyde-preserved Hancock xenograft from June, 1974, through June, 1977, were reviewed. This analysis included 403 patients: 202 having mitral valve replacement (MVR), 131 having aortic valve replacement (AVR), and 70 having mitral and aortic valve replacement (M/AVR). The hospital mortality was 9.9% (40/403): 10.8% (22/202) for MVR, 4.5% (6/131) for AVR, and 17.1% (12/70) for M/AVR. Of 363 patients discharged from the hospital, six were lost to follow-up at 24 and 37 months and they are excluded from the figures. There were 41 late deaths, which represents an incidence of 1.47% per patient-year for MVR (16/177), 1.95% per patient-year for AVR (14/122), and 3.35% per patient-year for the M/AVR (11/58). There were 37 thromboembolic events in 32 patients. This represents a linearized incidence of 1.93%, 0.97%, and 2.74% per patient-year for MVR, AVR, and M/AVR, respectively. None of the accidents was fatal, and four of the 32 patients were on a regimen of controlled anticoagulation at the time of embolism. Primary tissue failure was observed in 34 patients (231 MVR, eight AVR, and five MAVR). The probability of being free from primary tissue failure at 8 years is 85.3% +/- 3.7% for MVR, 85% +/- 11.6% for AVR, and 81% +/- 8.9% for M/AVR. These current results indicate that the Hancock xenograft valve can be considered as a valid alternative in heart valve replacement.     

Elderly valve replacement with bioprostheses and mechanical prostheses. Comparison by composites of complications

AIM: The goal of aortic valve replacement (AVR) surgery in the elderly (= or >75 years) is to extend survival and minimize valve-related morbidity, mortality and reoperation. As the elderly population lives longer, those with implanted valves are at risk of suffering valve related complications. We hypothesize that bioprostheses are appropriate for the elderly. METHODS: The follow-up evaluation of 966 patients with valves (AVR, 666; mitral valve replacements [MVR], 226; multiple valve replacements [MR], 74) implanted between 1975 and 1999 was examined. There were 879 bioprotheses (BP) and 87 mechanical prostheses (MP). The mean age was 78.9+/-3.3 years (range 75-94.6 years). Concomitant coronary artery bypass was performed in AVR in 51.7%, MVR in 50.4% and MR in 28.4%. Valve type, valve lesion, coronary artery bypass (previous/concomitant), age and gender were considered as independent predictors of composites and survival. The total follow-up was 3905 patient-years. RESULTS: Early mortality was for AVR 9.6% (64), MVR 15.0% (34) and MR 25.7% (19). The late mortality was for AVR 8.8%, MVR 10.4% and MR 8.8%/patient-year. The only independent predictor of survival and valve-related mortality, morbidity and reoperation was age for survival in those with AVR, hazard ratio 1.15 [CL 1.03-1.27] p=0.0094). The BP reoperative rate was 0.5%/patient-year (reoperation was fatal in 6/15) of total, MP reoperative rate was 0% [reasons for reoperation structural valve deterioration (4), non-structural dysfunction (6), prosthetic valve endocarditis (5), reoperation fatality due to non-structural dysfunction (2), prosthetic valve endocarditis (4)]. Overall patient survival at 10 and 15 years, respectively, was 30.5+/-2.4% and 3.6+/-2.2% irrespective of valve position and type. Overall actual and actuarial freedom from valve-related morbidity at 15 years was 96.8+/-0.9% and 93.7+/-2.3%, respectively. Actual and actuarial overall freedom from valve-related mortality at 15 years was 84.3+/-2.4% and 58.4+/-0.9%, respectively. Overall actual and actuarial freedom from valve related reoperation at 15 years was 95.8+/-1.6% and 74.8+/-16.9%, respectively. CONCLUSIONS: BP valves are further confirmed to be a good option for AVR in patients = or >75 years of age.     

Combining off pump coronary artery bypass with mitral valve replacement

Background Conventional approach to combined coronary artery bypass grafting (CABG) and mitral valve replacement (MVR) is associated with longer cardiopulmonary bypass (CPB) and aortic cross clamp (ACC) time leading to high operative risk. Methods We conducted a retrospective review of nine consecutive patients undergoing coronary artery bypass grafting/mitral valve replacement combining the off pump technique with cardioplegic arrest. Elective intra aortic balloon pump (IABP) support was instituted in all cases. CABG was first done in all cases without cardiopulmonary bypass support. Mitral valve replacement was then done using conventional cardiopulmonary bypass and cardioplegic arrest using the superior septal approach. Results Nine consecutive patients underwent coronary artery bypass grafting with mitral valve replacement including three patients with acute myocardial infarction. Preoperative echocardiogram revealed a mean ejection fraction (EF) of 38.4 ± 6.0%. Intra aortic balloon pump was inserted in all patients preoperatively. The average number of grafts were 3.0 ± 0.7. Eight patients received bioprosthetic valve while one patient received mechanical prosthesis. The average length of stay in intensive care unit was 3.3 ± 0.5 days. There was no mortality. One patient had superficial wound infection. Conclusion The data suggest that the combined technique (off pump coronary artery bypass grafting and conventional mitral valve replacement) is a safe method to perform coronary artery bypass grafting/mitral valve replacement with minimal morbidity and mortality.     

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

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

Surgery for cardiac valves and aortic root without cardioplegic arrest ("beating heart"): experience with a new method of myocardial perfusion

Simultaneous antegrade/retrograde warm blood perfusion with a beating heart has not been previously reported as a mean of protecting hypertrophied hearts in cardiac valve and aortic root surgeries. Similarly, beating heart mitral valve surgery via the trans-septal approach with the aorta unclamped, is a novel technique. We, herein, report a series of 346 patients with a variety of cardiac pathologies who were operated upon utilizing a new modality of myocardial perfusion. Among this group of patients, there were 55 patients who were diagnosed with endocarditis of one or more valves. These patients were excluded from this series of patients. Mean age was 59 +/- 12, and there were 196 (67.3%) males and 95 (32.7%) females. There were six aortic root procedures, 90 mitral valve replacements (MVR), 46 mitral valve repairs, 20 MVR+ coronary artery bypass grafting (CABG), 28 tricuspid valve repairs, 106 aortic valve replacements (AVR), 17 AVR+CABG, and 8 AVR/MVR. Crude mortality for the group was 20 of 291 (6.8%). Intra-aortic balloon pump utilization at time of weaning from cardiopulmonary bypass was 6/291 (2.06%), and re-operation for bleeding was needed in 12 of 291 (4.1%) patients. Postoperative stroke occurred in 4 of 291 (1.3%) patients. In these patients, the clinical diagnosis of stroke was made prior to surgery. This initial experience with this new method of myocardial perfusion indicates that results are at least comparable, if not superior, to conventional techniques utilizing intermittent cold blood cardioplegia.     

Nine years' experience with the Bj?rk-Shiley prosthetic valve: early and late results of 932 valve replacements

Between November, 1970, and December, 1977, 932 consecutive patients received the standard Bj?rk-Shiley prosthesis. Operative mortality was 4.6% for aortic valve replacement (AVR; N = 364), 5.1% for mitral valve replacement (MVR; N = 313); 11.3% for multiple valve replacement (N = 194), and 13.7% for valve replacement combined with coronary artery bypass grafting (CABG; N = 51). Factors influencing hospital mortality included type of valve replacement, age at operation, whether the valve replacement was done as an emergency, and year of implantation. Complete follow-up (mean, 3.7 years) was achieved in 95% of the survivors. Actuarial survival was 82% for AVR patients at 8 years, 83% for MVR patients at 7 years, 72% for multiple valve replacement patients at 7 years, and 76% for those who had valve replacement with CABG at 3 years. No significant difference in late survival was found between patients with mitral insufficiency alone (p greater than 0.2) or aortic insufficiency alone (p greater than 0.9) and those with stenotic lesions only. Thromboembolic complications occurred at an incidence of 1.17% per patient-year, and Dicumarol-induced hemorrhages occurred at an incidence of 2.11% per patient-year. Twelve out of 13 patients survived operation for prosthetic valve thrombosis, indicating that this complication is not as catastrophic as many believe. The incidence of reoperation in anticoagulated patients was 0.63% per patient-year. All of these results are compared with data from the recent literature.     

Comparison of short-term mortality risk factors for valve replacement versus coronary artery bypass graft surgery

BACKGROUND: Risk factors for 30-day operative (short-term) mortality following coronary artery bypass graft (CABG only) procedures are well established. However, little is known about how the risk factors for short-term mortality following valve replacement procedures (with or without a CABG procedure performed) compare with CABG only risk factors. METHODS: Department of Veterans Affairs (VA) records (65,585 records) were collected from October 1991 through March 2001 and analyzed. Risk factors for short-term mortality were compared across three subgroups of patients: CABG only surgery (n = 56,318), aortic valve replacement (AVR) with or without CABG (n = 7450), and mitral valve replacement (MVR) with or without CABG (n = 1817). Multivariable logistic regression analyses were used to compare the relative magnitude of risk for 19 candidate predictor variables across subgroups. RESULTS: Only three patient baseline characteristics differed significantly in magnitude of risk between the procedure groups. Partially or totally dependent functional status significantly increased the risk of short-term mortality for AVR patients (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.29-2.09) and MVR patients (OR 2.21, 95% CI 1.48-3.30), but not for CABG only patients (OR 1.04, 95% CI 0.93-1.16). Conversely, previous heart surgery and New York Heart Association functional class III or IV symptoms conferred greater magnitude of risk for CABG only patients compared with the valve subgroups. CONCLUSIONS: Overall, the risk factors for short-term mortality following valve replacement and CABG surgery appear to be relatively consistent. However, clinicians should be aware of the importance of preoperative functional status as a unique predictor of mortality following valve surgery.     

Multivariable prediction of in-hospital mortality associated with aortic and mitral valve surgery in Northern New England

BACKGROUND: Predicting risk for aortic and mitral valve surgery is important both for informed consent of patients and objective review of surgical outcomes. Development of reliable prediction rules requires large data sets with appropriate risk factors that are available before surgery. METHODS: Data from eight Northern New England Medical Centers in the period January 1991 through December 2001 were analyzed on 8943 heart valve surgery patients aged 30 years and older. There were 5793 cases of aortic valve replacement and 3150 cases of mitral valve surgery (repair or replacement). Logistic regression was used to examine the relationship between risk factors and in-hospital mortality. RESULTS: In the multivariable analysis, 11 variables in the aortic model (older age, lower body surface area, prior cardiac operation, elevated creatinine, prior stroke, New York Heart Association [NYHA] class IV, congestive heart failure [CHF], atrial fibrillation, acuity, year of surgery, and concomitant coronary artery bypass grafting) and 10 variables in the mitral model (female sex, older age, diabetes, coronary artery disease, prior cerebrovascular accident, elevated creatinine, NYHA class IV, CHF, acuity, and valve replacement) remained independent predictors of the outcome. The mathematical models were highly significant predictors of the outcome, in-hospital mortality, and the results are in general agreement with those of others. The area under the receiver operating characteristic curve for the aortic model was 0.75 (95% confidence interval [CI], 0.72 to 0.77), and for the mitral model, 0.79 (95% CI, 0.76 to 0.81). The goodness-of-fit statistic for the aortic model was chi(2) [8 df] = 11.88, p = 0.157, and for the mitral model it was chi(2) [8 df] = 5.45, p = 0.708. CONCLUSIONS: We present results and methods for use in day-to-day practice to calculate patient-specific in-hospital mortality after aortic and mitral valve surgery, by the logistic equation for each model or a simple scoring system with a look-up table for mortality rate.     

Management of aortic valve disease during aortic surgery

BACKGROUND: Outcomes and resource utilization of patients undergoing mitral valve replacement (MVR) with or without concomitant coronary artery bypass grafting (CABG) were reviewed. METHODS: Data for 1,844 patients undergoing isolated primary MVR at Emory University Hospitals between 1980 and 1997 were recorded prospectively in a computerized database. RESULTS: The four groups included patients undergoing elective MVR with (n = 360) or without CABG (n = 1332) and urgent/emergent MVR with (n = 66) or without CABG (n = 86). Length of stay was significantly higher in patients undergoing elective MVR with CABG (15 days) than in those without CABG (11 days) but was not significantly different in patients undergoing urgent/emergent MVR with CABG (17 days) than in those without CABG (19 days). In-hospital mortality was significantly higher for patients undergoing elective (14%) or urgent/emergent (41%) MVR with CABG than in those undergoing MVR without CABG (elective:6%; urgent/emergent:20%). The 19-year survival rate was 32% for patients undergoing elective MVR with CABG compared with 51% for those without CABG and 28% for patients undergoing urgent/emergent MVR with CABG compared with 46% for those without CABG. Multivariate correlates of long-term mortality included older age, concomitant CABG, and urgent/emergent status. Hospital costs were significantly higher for patients undergoing elective MVR with ($33,216) than for those without ($23,890) CABG. No significant difference in cost were noted between patients undergoing urgent/emergent MVR with ($40,535) and without ($31,981) CABG. CONCLUSIONS: The addition of CABG or urgent/emergent status to patients undergoing MVR significantly increases morbidity, mortality, and costs. Careful scrutiny of the benefits versus resource utilization is required for patients undergoing high risk MVR.