Apelin: A novel prognostic predictor for atrial fibrillation recurrence after pulmonary vein isolation.

Apelin, the ligand for the APJ receptor, is involved in the pathogenesis of atrial fibrillation (AF). However, whether serum apelin can predict the recurrence of AF after pulmonary vein isolation (PVI) has not been determined.A prospective cohort study was performed in patients with AF (but without structural heart disease) who were undergoing first-time PVI. Serum apelin-12 was measured by enzyme-linked immunosorbent assay. Echocardiographic examination was performed at baseline, 3 months, and 6 months after PVI. Patients were followed up for 6 months after PVI, and the association between baseline apelin-12 and AF recurrence (early recurrence: within 3 months after ablation; late recurrence: 3-6 months after ablation) was analyzed.A total of 61 patients were included in the study. Baseline serum level of apelin-12 was significant lower in patients with early (median [interquartile range]: 1844 [1607-2061] vs 2197 [1895-2455] ng/L, P = .01) and late (1639 [1524-1853] vs 1923 [1741-2303] ng/L, P = .02) AF recurrence compared with patients without these events. Results of Cox stepwise multivariate analysis demonstrated that lower baseline apelin-12 (<2265 ng/L) was independently associated with increased AF recurrence within 6 months after PVI (P < .05). The specificity and positive predictive value of apelin-12 for AF recurrence were significantly higher than those of baseline N-terminal brain proBNP (60.4% vs 28.6%, P < .001; 58.8% vs 34.4%, P = .01), although the sensitivity and negative predictive value were similar.Reduced baseline serum apelin-12 may be an independent risk factor for the recurrence of AF after PVI in patients without structural heart disease.