[Haemodynamic effects of nitroglycerin (author's transl)].

The haemodynamic effects of nitroglycerin (0.6 mg sublingual) have been studied in eleven patients with coronary artery disease, by means of the thermodilution method which enables cardiac output to be repeatedly measured at short time intervals (1-2 minutes). The following data have been studied: blood pressure (BP), pulmonary arterial pressure (PA), left ventricular filling pressure (LVFP), cardiac output (CO), stroke volume (SV), heart rate (HR), total systemic resistance (TSR), total pulmonary resistance (TPR), tension-time index (TTI) and left ventricular stroke work index (LVSWI). Within 1 minute following nitroglycerin (NG) administration the patients showed a decrease in TSR, TPR, and an increase in CO, SV, HR and LVCWI. TTI was reduced at the 5th minute. LVFP, PA and BP decreased after 3-5 minutes. CO increase at the 1st minute often compensated the fall in TSR, and blood pressure remained unchanged. The LVSWI/LVFP curve showed a transitory shift to the left at the 1st minute. In eleven normal subjects NG induced a minor increase in CO and SV, and a minor decrease in TSR at the 1st minute. The mechanism of action of NG in angina pectoris is briefly discussed.