P923Feasibility of the transcatheter mitral valve repair as the rescue therapy for patients with severe mitral regurgitation and endangered heart failure

Abstract

Abstract Background For those who carry high or prohibitive surgical risk, the transcatheter edge-to edge mitral valve repair using MitraClip has been a safe and effective treatment for severe mitral regurgitation (MR). In patients with severe MR and cardiogenic shock under hemodynamic supporting devices, emergent surgical mitral valve interventions carry extremely high risk for peri-operative morbidities and mortalities. The feasibility and efficacy of emergent MitraClip to rescue patients in critical conditions remains elucidate. Methods Patients with severe MR were evaluated by the heart team and those with high or prohibitive surgical risks were referred to receive MitraClip procedures. Emergent MitraClip were conducted in patients with unstable hemodynamics and under mechanical or inotropic support. The hemodynamic measures, transthoracic echocardiography, transesophageal echocardiography, and blood tests were performed before MitraClip procedures. Procedural success was defined as having mild mitral regurgitation immediately after MitraClip, and patients were free from in-hospital mortality. Clinical and echocardiographic outcomes were followed by telephones and clinics. Results Among 50 consecutive patients (74.7±11.2 years, 74% male), 8 emergent MitraClip procedures were conducted to rescue patients with cardiogenic shock. Extracorporeal membrane oxygenation were used in 2 patients and intra-aortic balloon pump were applied in 4 patients (50%). The rest of 4 patients received continuous inotropic agent administration. Compare to those who underwent elective procedures, patients underwent emergent MitraClip had higher surgical risk profile (Euroscore II 34.8% vs 5.1% and STS score 19.7% vs 5.1%), poorer renal function and higher right atrial pressure. There was no peri-procedural death, myocardial infarction, stroke or any adverse events requiring emergent cardiac surgery in both groups. Mild mitral regurgitation was achieved in 87.5% patients from the emergent group and 95.2% patients in the elective group (P=0.514). In follow up, there were 5 deaths (three in the emergent group), including 2 non-cardiovascular deaths. The Kaplan-Meier analysis showed patients who underwent emergent procedures have poorer long-term survival rate as compare to those who received elective procedures. (P value = 0.008). Conclusions When open-heart surgery is not feasible and deferred due to excessive risk, trans-catheter mitral valve repair is an alternative way to rescue patients in cardiogenic shock status. The emergent MitraClip procedure may provide comparable safety and efficacy in treating patients with severe MR and unstable hemodynamics.