Pulmonary arterial V waves in mitral regurgitation: clinical and experimental observations.

Pulmonary arterial early diastolic waves (V waves) were investigated in patients and experimental animals with mitral regurgitation. V waves exceeding systolic pressure in the pulmonary artery were recorded in the main pulmonary artery with micromanometer catheters both in patients and animals, eliminating the possibility of catheter artifact. In experimental animals, aortic closure preceded pulmonic closure by 33 +/- 12 msec at baseline. With the creation of acute mitral insufficiency, a pulmonary arterial V wave occurred in six of eight animals. Early pulmonic valve closure occurred only in the six animals with a pulmonary arterial V wave. In these animals, pulmonic closure preceded aortic closure by 28 +/- 7 msec during mitral insufficiency (p less than .05). Of 70 patients with severe mitral regurgitation at cardiac catheterization, 14 had a pulmonary arterial V wave. In five patients recordings with micromanometer catheters were made and early pulmonic closure was also observed in four of these patients who had pulmonary arterial V waves at rest or upon provocation. Patients with pulmonary arterial V waves had a more acute onset of symptoms, shorter duration of mitral regurgitation, higher pulmonary capillary wedge V waves, and lower pulmonary arterial resistances than patients without them and were more likely to have nonrheumatic mitral regurgitation.