Hemodynamic and volumetric effects of venodilation with nitroglycerin in chronic mitral regurgitation.

To evaluate the potential value of nitrate therapy in patients with chronic mitral regurgitation, the hemodynamic and angiographic effects of intravenous nitroglycerin were studied in 10 such patients. Nitroglycerin infusion, titrated to reduce mean pulmonary artery wedge pressure at least 20%, resulted in a significant reduction in mean blood pressure (from 91 +/- 12 to 77 +/- 13 mm Hg, p less than 0.0001), mean right atrial pressure (12 +/- 6 to 7 +/- 4 mm Hg, p less than 0.001), left ventricular end-diastolic pressure (22 +/- 7 to 13 +/- 5 mm Hg, p less than 0.0001) and peak V wave of indirect left atrial pressure (34 +/- 9 to 20 +/- 10 mm Hg, p less than 0.001). Changes in systemic vascular resistance (1,986 +/- 468 vs 1,582 +/- 534 dynes s cm-5) and forward stroke volume (39 +/- 14 vs 45 +/- 8 ml) were not statistically significant. Angiographic data showed a decrease in both end-diastolic and end-systolic left ventricular volumes (248 +/- 51 to 216 +/- 54 ml, p = 0.06 and 127 +/- 69 to 99 +/- 48 ml, p less than 0.05, respectively) and an improvement in ejection fraction, from 0.52 +/- 0.15 to 0.55 +/- 0.15 (p less than 0.05). There was no significant change in the group values for mitral regurgitant volume and fraction (from 85 +/- 32 to 72 +/- 32 ml and 67 +/- 10 to 64 +/- 5%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)