Impact of Left Ventricular Global Longitudinal Strain on Outcomes After Transcatheter Edge-to-Edge Repair in Secondary Mitral Regurgitation.

Assessment of left ventricular (LV) systolic function is essential in patient selection for transcatheter edge-to-edge repair (TEER) in secondary mitral regurgitation (MR). Although LV ejection fraction (EF) is mostly used for assessing LV function, it represents the change of LV chamber size, but not myocardial contractility. LV global longitudinal strain (GLS) provides an alternative to assess LV systolic function in patients with secondary MR. This study included 380 patients with secondary MR (mean age 71.0 ± 13.0 years; 61.1% male) who underwent TEER. Patients were dichotomized based on baseline LV GLS (more impaired GLS [<7.0%] vs less impaired GLS [≥7%]) based on existing literature. The primary outcome was all-cause mortality, whereas the secondary outcome was the composite end point of all-cause mortality and heart failure hospitalization. The mean LV GLS was 8.1 ± 3.8%, and 162 patients had GLS <7%. Patients with more impaired GLS (<7%) were more likely to be male (68.5% vs 55.5%; p = 0.01) and have larger LV end-diastolic volume (110.5 ± 36.5 ml/m vs 92.9 ± 34.3 ml/m; p <0.001) and lower LVEF (22.2 ± 8.9% vs 36.4 ± 14.5%; p <0.001) than those with less impaired GLS (≥7%). The number of clips used and residual MR were similar between the 2 groups. Patients with more impaired LV GLS (<7%) had significantly higher 2-year event rates of the primary outcome (38.2% vs 25.9%; log-rank p = 0.003) and the secondary outcome (52.5% vs 36.3%; log-rank p <0.001). Multivariate analysis showed that LV GLS (<7%) was independently associated with the primary outcome (hazard ratio 1.65, 95% confidence interval 1.16 to 2.34, p = 0.005) and the secondary outcome (hazard ratio 1.54, 95% confidence interval 1.08 to 2.20, p = 0.016) whereas such associations were not observed with LVEF. In conclusion, LV GLS (<7%) was independently associated with a higher risk of adverse events in patients with secondary MR who underwent TEER.