OBJECTIVES: The ability to detect residual regurgitation is important in the management of patients after mitral valve repair. We performed a study of 264 patients to determine the risk factors and to compare the accuracy of clinical assessment with that of echocardiography. METHODS: Operative details and valve pathologic data were obtained from individual patient case notes. Clinical assessment consisted of history, examination, and electrocardiography. The presence of regurgitation was ranked in 7 grades, from none to severe. Transthoracic echocardiography was performed blinded to and independently of clinical assessment on the same visit and was graded similarly. Univariate analyses of demographic, etiologic, and operative variables were performed. Significant factors were entered into a multivariate logistic regression model. Sensitivities and specificities were calculated for each diagnostic modality, and the kappa statistic was used to express agreement. RESULTS: Mean (+/- SE) freedoms from regurgitation at 1 and 5 years were 91.5% +/- 1.7% and 47.5% +/- 3.2%. Factors independently associated with postoperative regurgitation were poor ventricular function (P =.04), increased age (P =.01), and chordal procedures (P =.006). When assessing the presence of regurgitation, auscultation conferred a specificity of 78%, a sensitivity of 77%, and a kappa of 0.43 relative to echocardiography. Electrocardiographic criteria for left ventricular hypertrophy were superior, with a complete specificity of 100% but a low sensitivity of 15%. Agreement within 7 grades of severity was moderate, with a weighted kappa value of 0.42. CONCLUSIONS: The hazard function for regurgitation after mitral repair increases steadily after the third year, with ventricular function, age and chordal procedures as independent risks. Clinical assessment and electrocardiography are excellent in identifying regurgitation, but their agreement is less when grading severity.