Magnetocardiographic evaluation of nonarrhythmogenic flecainide-induced electrocardiographic T-wave inversion

Flecainide is used for pharmacological conversion of atrial fibrillation (AF), to maintain sinus rhythm in patients with paroxysmal AF and/or supraventricular tachycardia, or to prevent catecholaminergic polymorphic ventricular tachycardia (1, 2). However, flecainide has been shown to be proarrhythmic in vitro (3) and was associated with threefold increase in arrhythmic death in Cardiac Arrhythmia Suppression Trial patients with low ejection fraction. Thus, flecainide use is restricted to patients without structural heart disease (1, 2). Reported cases showing torsade de pointes with JT/QTc interval prolongation, increased spatial dispersion of ventricular repolarization (VR), and/or T wave inversion in the electrocardiogram (ECG) precordial leads (4), even in the absence of ischemia or other cardiomyopathy, suggest that comprehensive noninvasive monitoring of VR may be useful at least during the early phase of treatment with flecainide.