Functional mitral regurgitation: a 30-year unresolved surgical journey from valve replacement to complex valve repairs.

Functional mitral regurgitation remains one of the most complex and controversial aspect--for both clinicians and surgeons--in the management of mitral valve disease in the context of left ventricular dysfunction. Given the current absence of clear guidelines, as well as of results from randomized trials comparing the outcome of different surgical strategies potentially available for this complex scenario, surgical decision making for these high-risk patients poses a real dilemma in the daily practice. The resulting surgical choices often represent a questionable combination of surgeons' personal feeling, local supplies, patients' life expectancy and risk/benefit ratios, opinions and statements of the experts, and so on. This review provides an overview of the present knowledge about the complex pathophysiology underlying functional mitral regurgitation, the different pathophysiology-guided surgical techniques suggested in the last decades, as well as the current results following these different surgical techniques.