Comparison the efficacy of single and dual defibrillator orthogonal electrical cardioversion in persistent atrial fibrillation

Objective Atrial fibrillation (AF) is treated with DC shocks delivered transthoracically; however, in approximately 5 to 30% of patients, these shocks fail to restore sinus rhythm (SR). In this study, we aimed to evaluate whether delivering high-energy shocks at different axes using a single-device or dual-device orthogonal configuration could improve the success of cardioversion compared with standard DC shocks to restore SR. Method After TEE evaluation, 180 persistent AF patients were included in the study. In group 1, 50 patients underwent conventional DCCV; in group 2, 50 patients underwent orthogonal single-device DCCV; and in group 3, 80 patients underwent orthogonal dual-device DCCV. The conventional group DCCV electrode pads were positioned antero-lateral (Figure 1a). The orthogonal single-device group DCCV electrode pads were positioned antero-lateral and antero-posterior, and these pads were connected to a single defibrillator (Figure 1b). The orthogonal dual-device group DCCV electrode pads were positioned antero-lateral and antero-posterior, and these pads were connected to two defibrillators (Figure 1c). In conventional group; transthoracic electrical cardioversion was performed with delivery of synchronized biphasic DC shocks of 200, 200, and 270J using antero-lateral pads (Figure 1a,2). In orthogonal single-device group; transthoracic electrical cardioversion was performed with delivery of synchronized biphasic DC shocks of 200, 200, and 270J using antero-lateral and antero-posterior pads (Figure 1b,2). In the orthogonal dual-device group; transthoracic electrical cardioversion was performed with delivery of synchronized biphasic DC shocks of 100 + 100, 200 + 200, and 270 + 270J using antero-lateral and antero-posterior pads (Figure 1c,2). Cardioversion was considered successful if atrial P waves were unmistakably identified 5 min after the shock. Result The results of the study are shown in Figure 2. First DCCV shock success (conversion to SR) was significantly higher in group 3 than in group 1; in group 1: 70% vs in group 3: 85%; p=0.04, and in group 2; 80%. Second DCCV shock success was significantly higher in group 3 than in group 1 and 2; in group 1: 72% vs in group 3: 95 %; p<0.001, in group 2: 80% vs in group 3: 95%; p=0.007. Third DCCV shock success was significantly higher in group 2: 90% than in group 1: 74%; p=0.03, and in group 3: 97.5% than in group 1: 74%; p<0.001. CK, CK-MB, and hs-Troponin I levels were evaluated at baseline and at 6 and 12 hours after DCCV, and these parameters were similar among the three groups (p > 0.05). All patients who converted to SR remained in sinus rhythm until hospital discharge. Conclusion Double simultaneous DC shocks in an orthogonal configuration is an effective method than standart antero-lateral DC shocks for the cardioversion of persistant AF. These methods have similar safety.