| Abstract: | To assess the effects of nitroglycerin ointment (NTG) on hemodynamics and autonomic nervous activity, 17 normal subjects and 13 patients with severe congestive heart failure (CHF) were studied. In 12 normal subjects, NTG significantly increased the plasma norepinephrine concentration in association with a slight reduction in systolic blood pressure and a slight increase in heart rate, plasma cyclic adenosine monophosphate (cyclic AMP) concentration, and renin activity at 1 hr. All normal subjects complained of headache or felt heavy-headed after NTG administration. In the 13 patients with CHF, NTG significantly decreased plasma norepinephrine and cyclic AMP concentrations in association with a significant increase in the cardiac index and a significant reduction in pulmonary arterial diastolic pressure, systemic vascular resistance, systolic blood pressure, and heart rate. The effects occurred at 30 min after NTG administration and continued for 3 hr. Relief from dyspnea or orthopnea in patients with CHF was observed. NTG did not change the plasma cyclic GMP concentration in normal subjects and patients with CHF. We conclude that in patients with CHF, NTG decreases the enhanced sympathetic nervous activity, with concomitant beneficial effects on hemodynamics and improvement of clinical symptoms. In contrast, NTG increases sympathetic nervous activity in normal subjects. |
