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.