We describe a singular case of a 75-year-old woman affected by an anterior acute myocardial infarction in the subset of a very recent orthopaedic surgery. She had had severe mitral regurgitation on coronary angiography. A thorough cardiac echocardiographic examination revealed the particular mechanism of mitral incompetence, consisting of a dynamic anterior mitral leaflet displacement caused by a sustained compensatory left ventricle hypercontractility and favored by postsurgical moderate anemia and mild hypertensive hypertrophy. The use of beta-blockers and the avoidance of pure vasodilators permitted complete reversal of such mechanisms during the clinical course.