EXPERIENCES WITH BETA-ADRENERGIC BLOCKADE.

1. Seventeen cases of cardiac arrhythmias and one case of chronic orthostatic hypotension have been treated with oral or intravenons propranolol. 2. No effect was noted on the orthostatic hypotension of the one case treated. 3. Fifteen of the seventeen arrhythmias responded with good rate control. In three cases with ventricular arrhythmias and one with supraventricular tachycardia, a normal sinus rhythm was established. 4. The encouraging conversion of ventricular fibrillation to a normal rhythm with propranolol when other measures had failed, warrants consideration for this approach in the desperate situation. 5. Toxic manifestations included chest tightness in three; possible temporary aggravation of a pre-existent hearing loss in one; aggravation of failure and possible precipitation of cardiac arrest in one; possible temporary neurogenic effect in one; and the temporary elevation of transaminases and lactic dehydrogenase in one. 6. The presence of left ventricular failure is a major contraindication to the use of propranolol. 7. The marked effect of propranolol in controlling a variety of cardiac arrhythmias, whether or not related to digitalis intoxication, is highly significant and adds an important new drug to our armamentarium. [ABSTRACT FROM AUTHOR]