Valvuiar heart disease

To develop strategies for the management of high-risk patients, contemporary risk factors for operative mortality and postoperative ventricular dysfunction were identified in 214 patients undergoing mitral valve surgery in 1982 and 1983. Thirty-eight preoperative and perioperative variables were prospectively collected and analyzed by univariate and multivariate statistics. The overall mortality was 4.6% and the incidence of postoperative low-output syndrome (LOS) was 18.7%. Fortyseven patients with coronary artery disease (CAD) had a higher mortality and incidence of LOS (as evidenced by the need for inotropic drugs or counterpulsation to maintain blood pressure) (those with CAD 15% mortality, 40% LOS; those without CAD 2% mortality, 13% LOS; p < .05). The presence of unstable angina and ischemic mitral regurgitation further increased the risk. Age was also a predictor of outcome. Patients who died or had LOS were older (those who died, 65 7 years, those with LOS, 58 11 years) than patients who survived and did not have postoperative dysfunction (those who survived, 53 + 11; those with no LOS, 53 + 11; p < .01). Mitral regurgitation was associated with a higher (p < .05) mortality and incidence of LOS (mortality 10.5%, LOS 36%; n 76) than was mitral stenosis (mortality 0%, LOS 4%; n = 74) or mixed lesions (mortality 3%, LOS 15%; n = 64). In patients without CAD, mitral regurgitation remained a significant predictor of mortality and ventricular dysfunction. Seventeen patients with tricuspid insufficiency required tricuspid valve annuloplasty, and were at higher risk (mortality 18%, LOS 53%) than patients who did not require tricuspid annuloplasty (mortality 4%, LOS 18%; p < .05). Symptoms at rest (NYHA class IV) were predictive of postoperative outcome (those in NYHA class IV 21% mortality, 42% LOS; those in classes I, II, and III 1% mortality, 14% LOS; p < .01). The surgeon, sex, rhythm, timing of surgery, previous valvular surgery, cause of lesion, pulmonary arterial pressure, pulmonary vascular resistance, and cardiac index did not influence the mortality or incidence of postoperative LOS. By stepwise logistic regression, NYHA class, age, presence of CAD or a mitral regurgitant lesion, and the need for tricuspid annuloplasty were, in descending order of significance, risk factors independently predictive of mortality or postoperative LOS. Circulation 72 (suppl II), 11-120, 1985. THE RISK of operative mortality after mitral valve surgery in the 1960s ranged between 18% and 40%.1-6 Recent reports suggest that the current risk to patients undergoing mitral valve surgery is less than 10%.7 8 The factors predictive of outcome have changed as the results of surgery have improved.71 The inclusion of patients operated on in the 1970s with those undergoing surgery in the 1980s7' 8,12 obscures the analysis of the factors influencing morbidity and mortality. We therefore instituted a prospective evaluation of the risk From the Divisions of Cardiovascular Surgery and Cardiology, the Toronto General Hospital and the University of Toronto, Toronto, Ontario, Canada. Supported by the Heart and Stroke Foundation of Ontario, the Canadian Heart Foundation, and the Medical Research Council of Canada. Address for correspondence: Richard D. Weisel, M.D., Cardiovascular Surgery, Toronto General Hospital, 200 Elizabeth St., Eaton North 13-224, Toronto, Ontario, Canada M5G 2C4. 11-120 factors of morbidity and mortality after mitral valve surgery. Ventrcular dysfunction after mitral valve surgery is the most common cause of mortality.8' 12, 13 This study was designed to assess current factors that contribute to mortality and ventricular dysfunction after mitral valve surgery to develop strategies to improve the results in high-risk subgroups.