Aim: This study was performed to identify clinical parameters for predicting outcome of surgery for severe tricuspid regurgitation (TR). 38 patients (6 men, mean age 57짹8 years) with severe TR undergoing corrective surgery were prospectively enrolled. Methods and Results: Demographic evaluation, laboratory test, echocardiography, and/or cardiac catheterization were performed before surgery. Tricuspid valve replacement was performed in 30 patients. Mean postoperative follow-up duration was 20짹13 months. Event-free survival was defined as the freedom from postoperative complication resulting in prolonged postoperative hospital stay (���30 days), readmission due to heart failure or arrhythmia, major bleeding, endocarditis and death. Event-free survival at follow-up was 63 %. NYHA class, age at the time of surgery, blood pressure, pulse pressure, left ventricular ejection fraction, right ventricular fractional area change, and pulmonary artery pressure did not predict the outcome. Survivors without morbidity had higher body weight (P=0.03) and body mass-index (BMI; P=0.02), lower blood urea nitrogen level (BUN; P=0.03), and higher total cholesterol level (P=0.03). With BMI<21 kg/m2, sensitivity, specificity and positive and negative predictive values for predicting poor outcome were 54%, 92%, 78% and 79%, respectively (Fig). Conclusion: Low BMI and low cholesterol level predict poor clinical outcome in patients with severe TR late after left heart valve surgery.