OR19. Correlation between Circadian Variation of Idiopathic Ventricular Arrhytmia and Left Ventricular Intrinsic Systolic Function assessed by Speckle Tracking Echocardiography

Abstract

Abstract Aims To investigate the correlation between circadian variation of idiopathic ventricular arrhytmia (IVA) and left ventricular (LV) intrinsic systolic function. Methods This cross sectional study included 67 patients with IVA originated from ventricular outflow tract. All patients underwent 24-hour Holter monitoring and speckle tracking echocardiography examinations. The circadian variation of IVA burden and global longitudinal strain (GLS) were determined and statistical analysis was conducted to evaluate their correlation. Results A total 31 patients (46.3%) had impaired LV systolic function by GLS (-15.1% + 1.8% vs -21.3% + 2.0%; p = <0.001) with less variation in circadian PVC distribution (coefficient of variation 6 hourly 26.8% + 15.6 vs 52.0 % + 28.2%; p = <0.00). Impaired LV systolic function was found in 31 patients (46.3%) with less variation in circadian IVA distribution (coefficient of variation/CoV 6 hourly 26.8%+15.6) compared to patients with normal LV systolic function (CoV: 52.0%+28.2%; p = <0.001). Multivariate analysis showed that less variation in circadian PVC distribution [CoV<35%) is correlated with LV dysfunction (OR = 3.89, 95%CI 1.09-13.80, p = 0.036). Other independent factors were episode of non-sustained VT (OR = 14.4, 95%CI=2.36-88.55, p = 0.008), IVA burden >9% (OR = 6.81, 95%CI 1.35-34.41, p = 0.020), and male gender (OR = 14.4, CI 95%=2.02-101.1, p = 0.004). Conclusion This study is the first to show that lack of circadian variation of IVA is associated with impaired LV systolic function by GLS. The finding of this study suggested that chronotherapy of antiarrhytmia medication may prevent the development of LV dysfunction.