The effect of prophylactic nitroglycerin infusion on the incidence of regional wall-motion abnormalities and ST segment changes in patients undergoing coronary artery bypass surgery.

The effects of nitroglycerin (NTG) on regional wall-motion abnormalities, ST segment changes, and the incidence of myocardial infarction (MI), cardiac failure, and mortality were studied in 30 patients undergoing coronary artery bypass. Patients received continuous infusions of either normal saline or NTG (1 microgram/kg per min [low dose] or 2 micrograms/kg per min [high dose]) beginning at anesthesia and continuing for 4 hours postoperatively. The occurrence of wall-motion abnormalities as detected by transesophageal echocardiography was 38 events in the normal saline group (N = 10). Significantly fewer events (p < 0.05) were recorded in the low dose and high dose NTG groups (20 events and 15 events, respectively) compared to controls. There were no significant differences between the control and NTG groups with regard to the incidence of Holter ST segment events or the incidence of MI, cardiac failure, or cardiac death. NTG reduced the incidence of echocardiographic wall-motion abnormalities in a dose dependent manner while having no significant effect on other parameters examined.