Effects of nitroglycerin on myocardial excursions and velocities in the early hours of acute myocardial infarction.

The effects of sublingual nitroglycerin on septal and left ventricular wall motion were determined by echocardiography in the early hours of acute myocardial infarction (MI) in 20 patients admitted via a mobile coronary care unit. Left ventricular and septal echoes were obtained in 11 patients with acute anterior MI and in 9 with acute inferior MI before and after administration of 500 micrograms sublingual nitroglycerin. In the group with acute anterior MI, nitroglycerin did not significantly affect the B-C excursion, posterior wall excursion, and mean posterior wall velocity. Nitroglycerin significantly increased (P less than 0.01), however, the systolic septal excursion, systolic septal velocity, diastolic septal excursion, and diastolic septal velocity. In the group with acute inferior MI, nitroglycerin significantly increased the B-C excursion (P less than 0.01); posterior wall excursion (P less than 0.01); mean posterior wall velocity (P less than 0.01); systolic septal excursion (P less than 0.01); diastolic septal excursion (P less than 0.05), and diastolic septal velocity (P = 0.01) but did not affect the systolic septal velocity. All measurements were obtained by use of a method of labeling and describing specific points of the wall motion that has been described recently.