Relevant secondary mitral regurgitation occurs in 35–50% of patients with chronic heart failure and is associated with increased mortality. Surgical management of patients with mitral valve regurgitation and heart failure remains controversial. There are several questions which are not sufficiently clarified because of a lack of prospective randomised controlled trials: (1.) The indication for concomitant mitral valve surgery in patients undergoing coronary artery bypass grafting (CABG) with moderate to severe mitral valve regurgitation; (2.) the management of functional mitral valve regurgitation; (3.) the appropriate surgical strategy: repair or chordal-sparing replacement.