[Reversibility of a critical intraventricular conduction delay under flecainide and lacosamide by sodium bicarbonate].

The case of a 72-year-old female patient with arrhythmogenic syncope associated with a combination therapy of flecainide and lacosamide is presented. The authors believe in an additive effect of both drugs on myocardial voltage-gated sodium channels with extraordinary QRS widening, exit block with temporary pacing and complete reversibility through infusion of sodium bicarbonate as bail-out therapy.