Sympathetic Blockade of the Acutely Injured Heart

¹ Robert S. Marx Laboratories, Department of Surgery, Wayne State University School of Medicine, Detroit, and the Veterans Administration Hospital, Dearborn

1. The myocardial irritability of animals subjected to an acute embolization of the left circumflex coronary artery was decreased when the animals were pretreated with nethalide.

2. The marked cardiovascular deterioration noted in the control group of animals after occlusion of the left circumflex coronary artery was less pronounced if the animals had been pretreated with nethalide.

3. When the heart's ability as a pump was tested by a rapid intravascular fluid load, beta adrenergic blockade induced by nethalide (Pronethalol) impaired the cardiac function.

4. These studies suggest that the beta adrenergic blocking drug nethalide (Pronethalol) may be of value in the treatment of arrhythmias associated with an acute myocardial injury; however, it is important to maintain the pumping demands of the heart at a minimum during the use of this agent.