Role of sublingual nitroglycerin in patients with acute myocardial infarction

14 Patients with acute myocardial infarction were given 0.3 mg sublingual nitroglycerin within the first 12 hr of their acute myocardial infarction. 5 Min after sublingual nitroglycerin mean arterial pressure fell 9 mmHg (1.2 kPa) and remained significantly reduced for 30 min. Pulmonary capillary wedge pressure fell from a mean control value of 17 to 12 mmHg (2.3 to 1.6 kPa) and also remained reduced for 30 min. Heart rate was significantly raised and stroke work index reduced at 5 min. Patients with a stroke work index of greater than 55 g m per m² b.s.a. responded to nitroglycerin with a fall in both pulmonary capillary wedge pressure and stroke work index while in those with a stroke index of less than 55 9 m per m² b.s.a. stroke work index did not fall concomitantly with the fall in pulmonary capillary wedge pressure. In one patient, nitroglycerin led to a precipitous fall in arterial pressure and recurrence of chest pain.