Effects of Transcatheter Mitral Valve Repair With MitraClip on Left Ventricular and Atrial Hemodynamic Load and Myocardial Wall Stress

Aims: To evaluate the effects of MitraClip on left ventricular (LV) and left atrial (LA) myocardial wall stress as assessed with the use of N-terminal pro B-type natriuretic peptide (NT-proBNP) and strain imaging. Methods and results: Sixty-five patients with symptomatic moderate and severe mitral regurgitation (MR; age 75 +/- 9 y, 57% male, 89% functional MR) treated with the use of MitraClip were evaluated. Patients were divided according to 6-month NT-proBNP tertiles. Changes in echocardiographic parameters over 6 months were assessed. Reductions in LV end-diastolic volumes (178 +/- 77 mL to 170 +/- 79 mL; P = .045) and LV end-systolic volumes (120 +/- 70 mL to 111 +/- 69 mL; P = .040) were observed in the overall population. Interestingly, low NT-proBNP tertile patients showed slight improvements in LV and LA longitudinal strain, whereas high NT-proBNP tertile patients showed impairment. Conclusions: Although MitraClip induces hemodynamic unloading in patients with predominantly functional MR, myocardial wall stress is not consistently improved. In patients with reduced NT-proBNP, improvements in LA volume index and LV and LA strains were observed. Patients who showed an increase in NT-proBNP exhibited impairment in LV and LA strain, suggesting an increase of myocardial wall stress.