Noninvasive detection of spatiotemporal activation-repolarization interactions that prime idiopathic ventricular fibrillation

= 10). In survivors of idiopathic VF, RT gradients were steeper than in controls, without differences in the clinical electrocardiogram, consistent with the ex vivo results. Patients with idiopathic VF also showed local myocardial regions with distinctly early-versus-late RT that were more balanced in size than in controls. Premature beats originated more often from the early RT regions in idiopathic VF survivors than in patients with frequent PVCs only. Thus, idiopathic VF emerges from the spatiotemporal interaction of a premature beat from an early-repolarization region with critical repolarization dispersion in that region. Electrocardiographic imaging can uncover the co-occurrence of these abnormalities.