Prognostic Value of Pre-Operative Transthoracic Echocardiography in Patients with Primary Mitral Regurgitation

Mitral regurgitation is the second most prevalent valvular disease, with primary mitral regurgitation (PMR) accounting for 61%–67% of cases. Chronic PMR can result in progressive left ventricular remodeling and dysfunction, ultimately leading to heart failure or other adverse cardiac events. This, in turn, necessitates frequent referrals, hospitalizations, and cardiac surgeries. The optimal timing for PMR surgery has been a subject of ongoing debate and remains a controversial issue. Presently, it is recommended that patients with chronic PMR undergo earlier mitral valve surgery to enhance post-operative outcomes. For example, the recommendation of European and American guidelines about left ventricular end-systolic diameter for surgery has been altered from 45 mm to 40 mm. Echocardiographic parameters are regarded as noteworthy indicators for intervention in patients with PMR. Extensive research has been undertaken in the field of echocardiography to identify more effective indicators that can propose the optimal timing for surgery, encompassing both conventional and novel echocardiography parameters. However, some parameters are not known to clinicians and the cut-off values for these parameters have shown some variations. Furthermore, a comprehensive review of this topic is currently missing. Consequently, this review aims to provide a thorough summary and elucidation of the prognostic significance of various echocardiographic measurements and their corresponding cut-off values, to help the clinical decision-making and further improve the outcomes of patients with PMR.