RESUMO
BACKGROUND: Long-term outcomes after direct current cardioversion (DCCV) in patients that receive anticoagulation have demonstrated to have no adverse sequela. Less is known about the impact on atrial fibrillation (AF) outcomes and resource utilization of repeated DCCVs that are often required for long-term rhythm control. METHODS: A total of 4,135 AF patients >18 years of age that underwent DCCV with long-term system follow-up were evaluated. Patients were stratified by the number of DCCVs received: 1 (n=2,201), 2-4 (n=1,748), and ≥5 (n=186). Multivariable Cox hazard regression was used to determine the association of DCCV categories to the outcomes of death, AF hospitalization, AF ablation, DCCVs, and stroke/transient ischemic attack. RESULTS: The average follow-up of the patient population was 1,633.1±1,232.9 (median: 1,438.0) days. Patients who underwent 2-4 and ≥5 DCCVs had more comorbidities, namely hypertension, hyperlipidemia and heart failure. Anticoagulation use was common at the time of DCCV in all groups (89.1%, 91.2%, 91.9%, p=0.06) and amiodarone use increased with increasing DCCV category (30.1%, 43.4%, 52.2, p<0.0001). At 5 years, patients that received more DCCVs had higher rates of repeat DCCVs, AF hospitalizations, and ablations. Stroke rates were not increased. Though not statistically significant, 5-year death was increased when comparing DCCV >5 vs. 1, (HR=1.32 [0.89-1.94], p=0.17). CONCLUSIONS: This study found that the increasing number of DCCVs, despite escalation of other pharmacologic and nonpharmacologic therapies, is a long-term independent risk factor for repeat DCCVs, ablations, and AF hospitalizations among AF patients.
