Severe papillary muscle dysfunction substantiated by atrial pacing during cardiac catheterization

A patient experienced episodic pulmonary edema accompanying nocturnal angina pectoris. The symptoms were provoked at cardiac catheterization by atrial pacing. Simultaneous onset of chest pain, shortness of breath, and sudden appearance of a large V wave in the pulmonary artery wedge pressure contour confirmed acute mitral valve regurgitation. Rapid reversal of these changes after nitroglycerin administration supported "papillary muscle dysfunction" as the explanation for these hemodynamic changes.