P413Reduction in right ventricular pacing: is there a long term benefit in minimising ventricular pacing and extending intrisic rythm search?

Introduction: Many studies have shown that excessive right ventricular pacing (RVP) increases the incidence of heart failure (HF) and atrial fibrillation (AF). Aiming to reduce RVP, algorithms that minimise ventricular pacing (AMVP) have been implemented in modern pacemaker. Managed Ventricular Pacing (MVP) allows wider atrioventricular delays. This algorithm has shown benefit not only in patients with sinus-node disease (SND) but also in those with abnormal atrioventricular conduction (AVD). Purpose: This study aims to compare survival and events between patients with pacemaker and MVP algorithm versus patients with pacemaker and other AMVP . Methods: Retrospective, longitudinal and unicenter study that included 191 patients that implanted dual chamber pacemaker (PM). The mean follow up period was 61,35 months and was made by hospital clinical registries consultation. We compared patients with AMVP MVP (Group A) with patients with AMVP not MVP. The analysis was splited by reason for implantation: SND and AVD. The following events were considered: death from all causes (DAC), HF hospital admissions and AF. Results: Group A (n=100) had consistently lower RVP percentage for both patients with SND ( group A 7,62% vs group B 20,06%, p<0,05) and AVD (group A 32,36 % vs group B 54,85%, p<0,05). Group B (n=91) showed higher probability of HF admissions (log rank p=0,007) and no diference concerning DAC (log rank p>0,05) or AF (log rank p>0,05). During the follow up period, patients from group B with AVD had more AF (log rank p=0,03) requiring conversion to VVI (log rank p=0,010). On the other hand, survival tended to be higher in group A with SND but with no statistical significance (log rank p=0,056). The presence of a AMVP not MVP was an independent predictor for AF (HR 0,21 , CI 0,045-0,986, p<0,05) in patients with AVD. Conclusions: Similarly to what has been described, MVP reduced significantly the RVP in all patients apart from the reason of implantation. This reduction was reflected in less admissions for heart failure and a tendency to higher survival. In the light of most recent evidence, the search for intrisic rythm, even in patients with AVD, can reduce morbidity and permanent AF. Abstract P413 Figure. Kaplan Meier curves