Double external direct-current shocks for refractory atrial fibrillation

Encouraged by preliminary data using double external direct-current (DC) sh ocks in patients with atrial fibrillation refractory to single external DC shocks, we undertook a prospective study of all patients with atrial fibril lation of >1-month duration using a shock sequence with (1) 1 shock of 200 J anterior-posterior, (2) I shock of 360 J anterior-posterior, (3) 1 shock of 360 J apex-anterior, and (4) double shocks with configurations 2 and 3 d elivered almost simultaneously by 2 defibrillators. The double shocks appea red to be safe and restored sinus rhythm in approximately 2 of 3 of patient s in whom DC cardioversion failed with single shocks.