Transcatheter mitral valve repair for primary and secondary mitral regurgitation: new insights from a nationwide registry.

B This article refers to 'Italian Society of Interventional Cardiology (GIse) registry Of Transcatheter treatment of mitral valve regurgitaTiOn (GIOTTO): impact of valve disease aetiology and residual mitral regurgitation after MitraClip implantation' by F. Bedogni I et al i ., published in this issue on pages 1364-1376. b Mitral regurgitation (MR) is the most frequent heart valve disease in the community and the second most frequent cause of hospital referral.1-3 The distinction between primary and secondary MR is of utmost importance since they differ not only in the mechanism causing valve failure but also in their prevalence, prognosis and treatment. While the reduced risk of death associated with a grade 1+ residual MR was expected for primary MR, in which left ventricular dysfunction is the consequence of MR, this is less obvious for secondary MR, in which MR is not the cause but the consequence of left ventricular dysfunction. In this study, in both primary and secondary MR, a grade 1+ residual MR was a protective factor for 1-year mortality and patients with grade 3+/4+ residual MR were at high risk of early death (within 60 days) with 50% of deaths at 1 year. [Extracted from the article]