Single-lead VDD pacing—a serious alternative for atrioventricular synchronous pacing in patients with atrioventricular block?

This editorial refers to ‘Long-term follow-up of DDD and VDD pacing: a prospective non-randomized single-centre comparison of patients with symptomatic atrioventricular block’ by S. Marchandise et al ., on page 496 For >20 years, single-lead VDD pacemakers have been implanted in patients with atrioventricular (AV) block and normal sinus node function.1 A single tripolar or quadripolar passive fixation lead is placed in the apex of the right ventricle for unipolar or bipolar ventricular sensing and pacing. Two sensing rings floating in the right atrium are used for bipolar sensing of the atrial potential. Due to lacking wall contact of the atrial dipole in most patients, atrial potential amplitudes are lower than those of fixed atrial electrodes. Thus, a high atrial sensitivity allowed by a differential sensing amplifier is usually needed for AV synchronous pacing in single-lead VDD devices. Since atrial pacing is not possible, a sinus node disease is a contraindication for VDD pacing and has to be ruled out before implantation. Several registries and randomized trials have shown an equivalent therapeutic efficacy of single-lead VDD pacing2–4 compared with DDD pacemakers. Long-term complications5 and costs of AV synchronous pacing therapy may be reduced by single-lead VDD pacemaker implantation.6,7 Despite these encouraging results, single-lead VDD pacing did not get beyond a ‘niche’ therapy for AV synchronous pacing.8 The concern about …