Uncommon presentation of drug-refractory pacemaker-mediated common atrioventricular nodal reentrant tachycardia and a simple solution by reprogramming.

An 81-year-old woman who had undergone dual chamber pacemaker implantation for sick sinus syndrome was referred to our hospital with drug-refractory common atrioventricular (AV) nodal reentrant tachycardia. Ventricular pacing (Vp) following premature atrial contraction (PAC) with a long AV interval induced ventriculoatrial (VA) conduction, which allowed the tachycardia to be initiated. The sensed AV interval was shortened to 80 ms, allowing Vp during the refractory period of VA conduction. Postventricular atrial refractory period was shortened to 180 ms to sense PACs with short coupling interval. After reprogramming, the suppression of the tachycardia by blocking VA conduction following Vp was confirmed.