Left atrial appendage exclusion is effective in reducing postoperative stroke after mitral valve replacement

OBJECTIVE: This study aimed to evaluate the role of surgical left atrial appendage (LAA) exclusion in the prevention of stroke after mitral valve replacement (MVR). METHODS: We retrospectively reviewed clinical data of 860 patients who received MVR in our center from January 2008 to January 2013. The patients were randomly assigned to two surgical groups, namely LAA exclusion group (n = 521) and LAA nonexclusion group (n = 339) according to whether concurrent surgical exclusion of the LAA was to be undertaken or not before surgery in a blind fashion. MVR was performed by two experienced surgeons. The LAA was explored during the operation and mural thrombus removed in all cases. The LAA was left intact in nonocclusion group whereas the neck of the LAA was closed with a two-layer continued suture in exclusion group. The incidence of early postoperative ischemic stroke between the two groups was compared. RESULTS: The patients' age was 53 ± 12 years, with 48.1% male and 67.9% with rheumatic disease. Mural thrombosis was seen in 18.8% of the patients and atrial fibrillation (AF) coexisted in 62.4%. All operations were successfully performed and no difference was noted in in-hospital mortality, re-exploration for bleeding, and other major complications between the two groups. The incidence of ischemic stroke in LAA exclusion group was significantly lower than in nonexclusion group (0.6% vs. 2.7%, p = .011). The subgroup multivariate analysis showed that LAA exclusion significantly reduced the risk of postoperative stroke in patients with AF (odds ratio [OR] = 0.070, 95% confidence interval [CI]: 0.006-0.705, p = .025) but not in non-AF patients (OR = 1.902, 95% CI: 0.171-21.191, p = .601). CONCLUSIONS: Concurrent LAA exclusion during MVR is a safe and effective way to reduce postoperative ischemic stroke, particularly in patients with AF.