Impact of mitral valve repair in patients with mitral regurgitation undergoing coronary artery bypass grafting.

BACKGROUND: The benefit of concomitant mitral valve correction (replacement or reconstruction, MVR) and coronary artery bypass grafting (CABG) in patients with coronary artery disease and mitral regurgitation (MR) remains unclear. PATIENTS AND METHODS: 298 consecutive patients underwent CABG alone (n=196) or CABG+ MVR (n=102) between January 2003 and April 2008. Clinical data were collected and MR graded according to preoperative echocardiographic studies. Four severity grades of MR were determined and patients assigned accordingly. Echocardiographic follow-up was performed postoperatively to assess heart and valve function. Multivariate logistic regression analysis was performed for perioperative morbidity and mortality. RESULTS: Patients were comparable within the groups regarding age, gender, NYHA-class, ejection fraction and number of graft vessels. Perioperative mortality (10.8% vs. 5.1%, P < 0.05) and degree of MR were higher among CABG+MVR patients. Among patients with moderate to severe or severe MR, postoperative echocardiography showed an improvement of mitral regurgitation in 95% of CABG+MVR and in 64% of CABG only patients. In patients with mild or moderate MR, improvement rates of both groups were similar (74% and 69%, respectively). Postoperatively, ejection fraction increased in both groups (CABG+MVR: 31.3 +/- 8.5 to 36.4 +/- 11.2; CABG only: 29.9 +/- 6.1 to 33.3 +/- 8.1, P > 0.05). Significant predictors for peri-operative mortality were renal insufficiency, older age and NYHA class III/IV. CONCLUSIONS: For reduction of ischaemic MR, CABG+MVR is preferable in patients with moderate to severe or severe MR. Combined CABG+MVR procedures cannot be recommended for patients with a particular risk profile because of disproportionately high peri-operative mortality.