Percutaneous mitral valve repair with the MitraClip in patients with handgrip exercise-induced dynamic mitral regurgitation

Aim: To investigate whether patients with symptomatic heart failure and exercise-induced dynamic severe mitral regurgitation (MR) benefit from percutaneous mitral valve repair (PMVR). Methods: We included patients who underwent PMVR with the MitraClip system in an all-comers observational study. Handgrip echocardiography was performed in patients with a discrepancy between symptoms and echocardiographic findings at rest, giving rise to the suspicion of an exercise-induced increase in MR severity. The primary endpoint of the study was a composite of all-cause mortality or admission for heart failure at 1-year follow-up. The secondary endpoint was the reduction in NYHA functional class. Results: Two hundred twenty-one patients who underwent MitraClip implantation were included. Ninety-three patients with moderate to severe MR at rest received handgrip echocardiography prior to PMVR. The remaining 128 patients presented with severe MR at rest, making exercise echocardiography unnecessary. Handgrip exercise led to an increase in MR severity in 81% of patients with moderate MR at rest, irrespective of the subtype of MR. Following PMVR, patients with dynamic severe MR experienced comparable clinical improvement as patients Received: First Decision: Revised: Accepted: Published: x Science Editor: Copy Editor: Production Editor: Jing Yu Page 2 of 11 Spieker et al. Vessel Plus 2020;4:29 I http://dx.doi.org/10.20517/2574-1209.2020.28 with severe MR already at rest: During 1-year follow-up, 37 patients died, and 71 patients were re-admitted to the hospital because of heart failure. In this regard, 13 patients (30%) with dynamic severe MR experienced the combined endpoint, while 72 patients (43%) with severe MR at rest did as well (P = 0.121). Moreover, the majority of patients with dynamic severe MR similar to patients with severe MR at rest experienced clinical improvement from NYHA class III/IV to I/II (59% vs . 56%; P = 0.566). Conclusion: The data presented provide evidence of a clinical benefit from PMVR using MitraClip in patients with moderate MR at rest who display exercise-induced increases in MR severity during handgrip exercise.