Effect of mitral valve transcatheter edge-to-edge repair on indices of left atrial performance in chronic mitral regurgitation.

Abstract

Effect of transcatheter edge-to-edge repair (TEER) using MitraClip in patients with mitral regurgitation (MR) on left atrial (LA) kinetic energy (LAKE), an index of LA work, and LA strain, a measure of LA performance, have not been well defined. Patients with chronic primary or secondary 3+ or 4+ MR were analyzed pre- and post-TEER using MitraClip. LAKE was determined by echocardiography using LA stroke volume and A-wave velocity. Peak atrial longitudinal strain (PALS), peak atrial strain in early diastole, and peak atrial contraction strain (PACS) were obtained by speckle tracking echocardiography. Thirty-nine patients undergoing TEER with MitraClip were screened, 12 met criteria for analysis (9 primary and 3 secondary MR). Compared to pre-TEER, there was a significant increase post-TEER in LAKE (71.0±64.1vs. 177.5±167.9 dyne·cm·103 , respectively; p=.008) and Doppler transmitral A-wave velocity (87.8±41.4vs. 138.5±43.7cm/s, respectively; p<.001); LA stroke volume did not change significantly. Mitral valve mean gradient significantly increased post-TEER compared to pre-TEER (5.7±2.1vs. 3.3±2.1mmHg, respectively; p=.01). There was a trend toward decrease in PALS post-TEER compared to pre-TEER (16.2±4.8vs. 20.7±9.9%, respectively; p=.05). Peak atrial strain in early diastole significantly decreased post-TEER compared to pre-TEER (7.2±3.0vs. 14.1±7.2%; respectively, p<.001), while PACS did not significantly change (9.1±3.5vs. 6.7±5.2%, respectively; p=.07). In patients with chronic MR, LAKE increases after TEER with MitraClip driven by an increase in LA emptying velocities. Changes were also seen in LA strain with MitraClip. These procedurally induced changes due to mild mitral stenosis may have clinical implications.