Rest and exercise oxygen uptake and cardiac output changes 6 months after successful transcatheter mitral valve repair

Aims Changes in peak exercise oxygen uptake (VO2) and cardiac output (CO) 6 months after successful percutaneous edge‐to‐edge mitral valve repair (pMVR) in severe primary (PMR) and functional mitral regurgitation (FMR) patients are unknown. The aim of the study was to assess the efficacy of pMVR at rest by echocardiography, VO2 and CO (inert gas rebreathing) measurement and during cardiopulmonary exercise test with CO measurement. Methods and results We evaluated 145 and 115 patients at rest and 98 and 66 during exercise before and after pMVR, respectively. After successful pMVR, significant reductions in MR and NYHA class were observed in FMR and PMR patients. Cardiac ultrasound showed reverse remodelling (left ventricular end‐diastolic volume from 158 ± 63 mL to 147 ± 64, P