Determinants of outcome in patients with heart failure with reduced ejection fraction & secondary mitral regurgitation

Changes in Left Ventricular Global Longitudinal Strain in Patients With Heart Failure and Secondary Mitral Regurgitation: The COAPT Trial

Background Left ventricular (LV) global longitudinal strain (GLS) provides incremental prognostic information over LV ejection fraction in patients with heart failure (HF) and secondary mitral regurgitation. We examined the prognostic impact of LV GLS improvement in this population. Methods and Results The COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) trial randomized symptomatic patients with HF with severe (3+/4+) mitral regurgitation to transcatheter edge-to-edge repair with the MitraClip device plus maximally tolerated guideline-directed medical therapy (GDMT) versus GDMT alone. LV GLS was measured at baseline and 6-month follow-up. The relationship between the improvement in LV GLS from baseline to 6 months and the composite of all-cause death or HF hospitalization between 6- and 24-month follow-up were assessed. Among 383 patients, 174 (45.4%) had improved LV GLS at 6-month follow-up (83/195 [42.6%] with transcatheter edge-to-edge repair+GDMT and 91/188 [48.4%] with GDMT alone; P=0.25). Improvement in LV GLS was strongly associated with reduced death or HF hospitalization between 6 and 24 months (P<0.009), with similar risk reduction in both treatment arms (Pinteraction=0.40). By multivariable analysis, LV GLS improvement at 6 months was independently associated with a lower risk of death or HF hospitalization (hazard ratio [HR], 0.55 [95% CI, 0.36-0.83]; P=0.009), death (HR, 0.48 [95% CI, 0.29-0.81]; P=0.006), and HF hospitalization (HR, 0.50 [95% CI, 0.31-0.81]; P=0.005) between 6 and 24 months. Conclusions Among patients with HF and severe mitral regurgitation in the COAPT trial, improvement in LV GLS at 6-month follow-up was associated with improved outcomes after both transcatheter edge-to-edge repair and GDMT alone between 6 and 24 months. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01626079.

Prognostic value of myocardial work and global longitudinal strain in patients with heart failure and functional mitral regurgitation

In patients with heart failure and functional mitral regurgitation (FMR), the assessment of left ventricular (LV) function is important for risk stratification and decision making. As LV ejection fraction (LVEF) might not be an optimal metric for LV systolic performance in this population, alternatives such as global longitudinal strain (GLS) and global myocardial work index (GWI) have been proposed. In the present study, we investigated the prognostic value of GLS and GWI and compared these measures to other LV systolic performance parameters. A prospective and consecutive cohort of 181 patients (median age 72 years, 76% male) with LVEF < 50% and FMR underwent comprehensive echocardiographic examination including speckle tracking echocardiography and grading of FMR severity. During a median follow-up of 42 months, 72 cardiovascular (CV) events occurred. In univariate analysis, LVEF, GLS, GWI, mitral S', LV outflow tract time velocity integral, forward LVEF and LV ejection time were associated with CV events. After multivariate adjustment only GLS (hazard ratio (HR) = 0.884, p = 0.015) and GWI (HR = 0.927, p = 0.034) remained independently associated with CV events. There was no difference in the incremental prognostic value of GWI compared to GLS (delta -2 log likelihood = 0.8; p = 0.37). In this cohort of heart failure patients with FMR, GLS and GWI were independently associated with cardiovascular events, whereas other systolic performance parameters were not. However, GWI did not outperform GLS, and further research is required to determine the value of these strain-based measures in clinical practice.