Dopexamine hydrochloride in chronic congestive heart failure with improved cardiac performance without increased metabolic cost

Abstract

Dopexamine hydrochloride is a new intravenous, short-acting agent with agonist activity at beta 2-adrenergic and DA1-dopaminergic receptors. The effects of dopexamine hydrochloride infusion on systemic and coronary hemodynamics, myocardial metabolism and the neuroendocrine system were evaluated in 10 patients with chronic severe congestive heart failure at baseline, at rates of 1, 2, 4 and 6 micrograms/kg/min at 15-minute intervals, and after a 1-hour infusion of the "optimal" dose. Right atrial pressure was reduced by 25% (p less than 0.01), pulmonary capillary wedge pressure by 26% (p less than 0.05), systemic vascular resistance by 44% (p less than 0.001) and pulmonary vascular resistance by 34% (p less than 0.01) after the optimal dose. Heart rate increased by 17% (p less than 0.01), rate-pressure product by 17% (p less than 0.01) and stroke volume index by 31% (p less than 0.001). There was no change in mean arterial pressure, myocardial oxygen consumption, coronary sinus blood flow, myocardial oxygen extraction or norepinephrine balance. None of the patients demonstrated net myocardial lactate production. These findings suggest that dopexamine hydrochloride improves systemic hemodynamics and cardiac performance without adversely affecting myocardial energetics or norepinephrine balance. Thus, dopexamine hydrochloride may be a useful agent for the short-term treatment of congestive heart failure.