Pathophysiology of Ischaemic Mitral Valve Prolapse: A Review of the Evidence and Implications for Surgical Treatment

Ischaemic mitral prolapse (IMP) is a pathologic entity encountered in about one-third of patients undergoing surgery for ischaemic mitral regurgitation. IMP is generally the result of a papillary muscle injury consequent to myocardial infarction, but the recent literature is progressively unveiling a more complex pathogenesis. The mechanisms underlying its development are the impairment of one or more components of the mitral apparatus, which comprises the annulus, chordae tendineae, papillary muscle, and left ventricular wall. IMP is not only a disorder of valvular function but also entails coexistent aspects of a geometric disturbance of the mitral valve configuration and of the left ventricular function and dimension. A correct understanding of all these aspects is crucial to guide and tailor the correct therapeutic strategy to be adopted. Localisation of prolapse and anatomic features of the prolapsed leaflets and the subvalvular apparatus should be carefully evaluated as also constituting the major determinants defining patient outcomes. This review will summarise our current understanding of the pathophysiology of and clinical evidence on IMP, with a particular focus on surgical treatment.