Haemodynamic effects of nitroglycerin infusion in patients with postinfarction heart failure

On the basis of their own 5-year experience, the authors discuss the indications for, and limitations of, intravenous infusion of nitroglycerin (NTG). In 42 patients with postinfarction heart failure, NTG produced a significant reduction of left ventricular filling pressure, regardless of its initial value. In patients with normal or only slightly elevated left ventricular filling pressure, NTG caused a decrease in cardiac index and mean arterial pressure as well as, in the earliest phase of infusion, an increase in peripheral resistance. Similar trends were observed also in patients with markedly elevated left ventricular filling pressure if mean arterial blood pressure fell by more than 20%. Taking into consideration that the range of the effective doses was very wide (15-150 micrograms/min), the authors believe that intravenous NTG infusion is indicated mainly in cases of manifest heart failure and should be administered under strict control of the dosage and with careful monitoring of the therapeutic effects.