P4720Noninvasive evaluation of single-dose intravenous 5-lipoxygenase inhibitor effect on ventricular repolarization variability in patients with mild-to-moderate chronic heart failure

Background: Sudden cardiac death is a major cause of death in the growing population of patients with heart failure (HF). In addition to reduced left ventricular ejection fraction other risk markers such as abnormal repolarization or electrical instability may have better predictive value. Novel magnetocardiography (MCG) inverse approach and automated techniques were developed for imaging of cardiac spatial repolarisation dispersion (SRD) alternates. The aim of this study was to assess the effect of intravenous 5-lipoxygenase inhibitor quercetin by evaluation of the dynamic changes of ventricular repolarization heterogeneity in patients with HF. Methods: Eleven males' patients (mean age 67.5±2.7 years) with mild-to-moderate chronic HF (NYHA II-IV) were studied. All participants underwent a complete clinical examination, including 12-channel ECG, high-resolution ECG, echocardiography, and MCG before 20 min of infusion quercetin and were repeated after two hours of treatment. MCG was recorded by means of 9-channel MCG system in non-shielded MCG laboratory. Inverse MCG imaging at each time instant was computed for the whole duration of the heartbeat. The SRD was automatically defined as the time interval from the earliest T-wave end to the latest T-wave end by using the time evolution of current density variables map.