Direct current conversion of atrial fibrillation.

Abstract

demonstrated the safety of direct current shock and its effectiveness in abolish- ing ventricular fibrillation. Soon afterwards the use of this method was extended to the treatment of atrial fibrillation (Lown, Amarasingham, and Neu- man, 1962a). The direct current shock causes complete depolarization of cardiac muscle, allowing the sinus node to take over as pacemaker. The safety of the method depends on careful synchron- ization of the direct current discharge to avoid the vulnerable T period of the cardiac cycle. Several papers (Killip, 1963; Lown et al., 1963; Oram et al., 1963; McDonald, Resnekov, and O'Brien, 1964) reported a high percentage of successful conversions and minimal complications.