Variation of Left Atrial Function in Different Stages of Mitral Regurgitation and Its Association With...

The current guidelines associate indications for surgery in mitral regurgitation (MR) with left ventricle size and function. However, there is not enough emphasis in current guidelines on left atrial function, which is thought to be an important factor predicting adverse outcomes in MR. The aim of this study was to investigate the left atrial function at different stages of mitral regurgitation and its value in predicting the indications of mitral valve surgery.

This was a retrospective study with 163 consecutive chronic primary MR patients who underwent color doppler echocardiography at the Guangxi Zhuang Autonomous Region Second People's Hospital between January 2016 and June 2018. All patients were in sinus rhythm, classified into three groups, according the degree of mitral regurgitation. Comparison was made with 30 control patients. Using Simpson's methods, we recorded maximal left atrial volume, left atrial volume before active contraction and minimal left atrial volume, from which left atrial expansion index, left atrial passive emptying fraction, left atrial active emptying fraction, and the total left atrial emptying fraction were derived.

Left atrial volume was expanded and left atrial emptying fraction was reduced in the mitral regurgitation group. By multivariate analysis, left atrial passive emptying fraction and left atrial active emptying fraction were independent predictors of mitral regurgitation requiring surgery. Using receiver-operating characteristic analysis, left atrial passive emptying fraction <97.4% demonstrated 98% sensitivity and 67% specificity for predicting the presence of surgical indication (area under the curve: 0.91; P < .001).

During mitral regurgitation, left atrial volume increases and functions decrease. The left atrial passive emptying fraction can be used as an additional tool to predict the indications of mitral valve surgery.