Role of left atrial appendage obliteration in stroke reduction in patients with mitral valve prosthesis: a transesophageal echocardiographic study.

OBJECTIVES

The aim of our study was to assess whether left atrial appendage (LAA) ligation in patients undergoing mitral valve replacement is associated with the risk of future embolisms.

BACKGROUND

Previous studies show that the LAA plays an important role in the development of intracardiac thrombus. According to this decisive role, LAA surgical closure in patients undergoing cardiac surgery may be an attractive choice for reducing stroke.

METHODS

We retrospectively studied 205 patients with previous mitral valve replacement and referred for echocardiography study. Patients were excluded if other causes of systemic embolism were found. The main outcome measure was the occurrence of an embolic event.

RESULTS

Ligation of LAA was performed in 58 patients. However, an incomplete ligation was verified in six patients. During a median time from valve replacement to echocardiography study of 69.4 months (1 to 329), 27 patients had an embolism. Multivariate analysis identified the absence of LAA ligation (odds ratio [OR] 6.7 [95% confidence interval [CI] 1.5 to 31.0]; p = 0.02) and the presence of left atrial thrombus as the only independent predictors of occurrence of an embolic event. Moreover, when the identification of an incomplete LAA ligation was considered together with the absence of LAA ligation, risk of embolism increased up to 11.9 x (OR 11.9 [95% CI 1.5 to 93.6]; p = 0.02).

CONCLUSIONS

Our study shows that LAA ligation during surgery of mitral valve replacement, performed in a high-risk population, is consistent with a reduction of the risk of late embolism and supports this technique if a mitral valve replacement is indicated.