SEVERAL methods have been developed in the past decade for the management of patients with repeated episodes of cardiac asystole or ventricular rates too slow to permit adequate perfusion of vital organs. Drug therapy has often proved disappointing. Recent emphasis has centered on various mechanical means of controlling the ventricular rate. Zoll and his co-workers1 have pioneered in the latter approach, employing external cardiac pacemakers that require relatively high voltage and current density. Skin burns have resulted from prolonged use — that is, for more than twenty-four hours. Severe pain has also been a problem. Weirich, Gott and Lillehei2 treated . . .