Evaluation and comparison of strain and myocardial work parameters in patients undergoing percutaneous edge-to-edge mitral valve repair with mitraclip system

Myocardial Work (MW) is an advanced echocardiographic technique that assesses left ventricular performance, considering the hemodynamic load on the ventricle. Unlike traditional measures such as ejection fraction (EF) and global longitudinal strain (GLS), MW provides a comprehensive evaluation throughout the cardiac cycle.

This study evaluates and compares echocardiographic parameters, specifically GLS and MW, before and after percutaneous edge-to-edge repair with the Mitraclip system, to highlight post-procedural improvements in ventricular performance.

A total of 59 patients with severe symptomatic mitral regurgitation, candidates for Mitraclip, were enrolled from March 2023 to April 2024. Parameters included GLS, Global Work Index (GWI), Global Constructive Work (GCW), Global Wasted Work (GWW), and Global Work Efficiency (GWE). Pre- and post-procedure measurements were analyzed using paired t-tests, considering patient comorbidities. The chi-square test and logistic regression were used to evaluate associations and predictive capacities.

Significant improvements were observed in post-procedural GLS (-9.17±5.95 to -13.41±5.22, p=0.0001), GWI (p < 0.005), and GWE (p < 0.005), with a reduction in GWW (p = 0.0001). In hypertensive and non-hypertensive patients there was a significant increases in GWI and GWE, and reduction in GWW. In diabetic and dyslipidemic patients there was a significant improvements in GWI, GWE, GLS and reduction in GWW. In patients with atrial fibrillation there was a significant improvements in GWI, GWE, GLS and reduction in GWW. In patients with coronary artery disease patients there was a significant increases in GWI and GWE. No significant changes in GCW were observed in any group. For degenerative mitral regurgitation (DMR), leaflet fibrosis was associated with residual mitral regurgitation post-procedure (more than mild). In functional mitral regurgitation (FMR), ischemic etiology was not significantly associated with residual regurgitation (more than mild). Logistic regression indicated that reduced GWI and increased GLS were linked to adverse outcomes, though not statistically significant.

GLS and MW are highly sensitive and useful non-invasive diagnostic parameters compared to ejection fraction, demonstrating improvements in myocardial work efficiency and ventricular performance post-Mitraclip. Long-term follow-up studies are needed to confirm the durability and clinical outcomes of these benefits.