Electrophysiological study as a predictor of mortality in unexplained syncope

Background: Electrophysiological study can help in the diagnosis of arrhythmic syncope. According to the electrophysiological study finding, the prognosis of patients with syncope is still a matter of study. Objective: The aim of this study was to assess the survival of patients undergoing electrophysiological study according to their findings and to identify clinical and electrophysiological independent predictors of all-cause mortality. Methods: A retrospective cohort study included patients with syncope who underwent electrophysiological study from 2009 to 2018. A Cox logistic regression analysis was performed to identify independent prognostic factors for all-cause mortality. Results: We included 383 patients in our study. During a mean follow-up of 59 months, 84 (21.9%) patients died. The split His group had the worst survival compared with the control group, followed by sustained ventricular tachycardia and HV interval ≥ 70 ms, respectively (p =.001; p <.001; p =.03). The supraventricular tachycardia group showed no differences compared with the control group (p =.87). In the multivariate analysis, independent predictors of all-cause mortality were Age (OR 1.06; 1.03–1.07; p <.001); congestive heart failure (OR 1.82; 1.05–3.15; p =.033); split His (OR 3.7; 1.27–10.80; p =.016); and sustained ventricular tachycardia (OR 1.84; 1.02–3.32; p =.04). Conclusion: Split His, sustained ventricular tachycardia, and HV interval ≥ 70 ms groups had worse survivals when compared to the control group. Age, congestive heart failure, split His, and sustained ventricular tachycardia were independent predictors for all-cause mortality.