Percutaneous “edge-to-edge” leaflet repair in patient with primary mitral valve regurgitation

Mitral regurgitation (MR) is the most common left-sided heart valve disease in developed countries with a constantly rising number of patients requiring hospitalization or intervention. Organic MR is defined as a primary structural abnormality of the mitral valve (MV) apparatus which may be caused by a broad set of pathological processes, among which myxomatous degeneration of the leaflets causing MV prolapse is the most common. If left untreated, chronic severe MR leads to serious adverse outcomes, from heart failure to death, but medical therapy is unable to change the natural history of the disease. Surgical correction, by means of valve repair or replacement, is the gold standard for the treatment of symptomatic patients with severe primary MR. However, surgery is not feasible for a large percentage of patients because of old age, reduced left ventricular ejection fraction and the presence of severe comorbidities. Therefore, in recent years, several percutaneous therapeutic alternatives suitable for high or prohibitive surgical risk patients were developed. In this review we discuss the transcatheter treatment of primary MR, from available evidence to technical practice, with a focus on the percutaneous “edge-to-edge” leaflet repair performed with the MitraClip System and the PASCAL Repair System.