The Challenge of Timing Surgery in Degenerative Mitral Regurgitation Is B-Type Natriuretic Peptide the Solution? ∗

Degenerative mitral regurgitation (MR) with prolapse or flail of mitral leaflets has become the most frequent cause of severe primary MR in Europe and North America (1,2). In its chronic stage, even severe MR is tolerated very well for a surprisingly long time, and patients may remain asymptomatic for years. During this compensated stage of disease, pre-load, afterload, and both contractility and ejection fraction of the left ventricle (LV) remain normal, and the total stroke volume is increased as a result of the compensatory enlargement of the end-diastolic LV volume, which is enabled by an adaptive process of the LV myocardium(3). However, these compensatory adaptions of the  LV eventually fail, and patients enter via a still-reversible transition phase into a decompensated stage where myocardial damage becomes irreversible(3). Without timely relief of the burden of volume overload to the LV and left atrium by surgical correction of MR, patients develop left heart failure, atrial fibrillation, and secondary pulmonary hypertension with eventually right heart failure (1,2). Considering the high long-term morbidity and mortality of degenerative MR on the one hand and the increasingly good results of surgical valve repair on the other, intervention has become recommended earlier and earlier over the years. Two critical questions remain, however: what is early enough, and what may possibly be too early? Observational studies have demonstrated that patients who already have sev...
Source: Journal of the American College of Cardiology - Category: Cardiology Source Type: research