Echocardiographic determinants of ventricular arrhythmia in sickle cell disease

Abstract

Unexplained sudden death remains a leading cause of death in sickle cell disease (SCD) adults. Ventricular arrhythmia is a well-known risk factor for sudden death but its prevalence and determinants in SCD remain understudied. The aim of this study was to identify echocardiographic predictors of ventricular arrhythmia in SCD. From January 2019 to March 2021, SCD adults referred to ambulatory cardiology department for possible cardiac involvement were prospectively included (Drepacoeur cohort). Patients that had 24-hours ECG monitoring (24 h-Holter) and thransthoracic echocardiography (TTE) on the same day were analysed. The primary end point was the occurrence of ventricular arrhythmia (sustained or non-sustained ventricular tachycardia (VT), more than 500 premature ventricular contractions (PVC) on 24 h-Holter, or history of VT ablation). Overall, 90 patients were included and 54 (60%) analysed. Mean age was 47.6 ± 11.6 years (range 21–69), 53% were male. Heart function was mainly preserved with a mean left ventricular ejection fraction (LVEF) of 57.9 ± 4.9% and a mean global longitudinal strain (GLS) of −18 ± 2.8%. Mean tricuspid regurgitation velocity was 2.6 ± 0.4 m/s. Ventricular arrhythmia was observed in 13 (24.1%) patients (4 non-sustained VT, 9 with more than 500 PVC and 1 history of VT ablation). Ventricular arrhythmia was associated with lower GLS (−15.8 ± 1.8% vs. −19 ± 2.7%, P < 0.001), lower tricuspid annular plane systolic excursion (TAPSE 23 ± 5.7 mm vs. 26.9 ± 4.6 mm, P = 0.02) and more dilated right ventricle assessed by tricuspid annulus diameter (38.2 ± 6.1 mm vs. 34.2 ± 4.5 mm, P = 0.02). In multivariate analysis, GLS was independently associated with ventricular arrhythmia (OR = 2.1, 95% CI [1,3; 3,3], P = 0.004) with a moderate exponential correlation with PVC load on 24 h-Holter (R = 0.5, P < 0.001). In SCD adults with preserved LVEF, GLS was the only independent echocardiographic predictor of ventricular arrhythmia.