title: Ventricular Rate Stabilization In Patients With Permanent Atrial Fibrillation And Single-Chamber Ventricular Pacemaker: RARE-PEARL Study.
abstract: Background:In patients with permanent atrial fibrillation (AF) rate irregularity can cause symptoms and impair the pumping function of the heart. Ventricular pacing at a rate close to the mean spontaneous ventricular rate can result in a more stable ventricular rate. Specific algorithms for automatic Ventricular Rate Stabilization (VRS) were designed and implemented in commercially available pacemakers. To assess this dynamic rate control we designed the RARE-PEARL study: prospective, randomized, cross-over, double-blinded.Methods:Patients with permanent AF, symptomatic episodes of brady-tachycardia, left ventricular ejection fraction (LVEF) >40%, NYHA class I/II/III, were eligible for enrolment. Each patient (n = 67) was implanted with a single-chamber VVIR pacemaker (models C20 or T20, Vitatron BV, The Netherlands) equipped with the VRS algorithm. At the end of a four week stabilization period, patients were randomized to VRS algorithm ON or OFF (2 months) and then crossed-over for the second phase (2 months). Primary endpoint was patient's preference.Results:Sixty six patients ended the study: 19 (29%) had no preference; 15 (23%) preferred algorithm OFF, 32 (48%) algorithm ON (p<0.0001, algorithm ON vs OFF). In 58% of patients the algorithm ON caused an increase of ventricular pacing percentage > 10%. The ventricular pacing percentage was 82±10% with algorithm ON vs 59±26% with algorithm OFF (p<0.0001). Symptoms did not differ significantly.Conclusions:The VRS algorithm significantly increases the ventricular pacing percentage in patients with permanent AF. This pacing function is preferred by the majority of patients implanted with a single-chamber VVIR pacemaker.
authors.affiliation: Cardiology Department, AOU Maggiore della Carità, Novara, Italy.
authors.forename: Eraldo
authors.initials: E
authors.lastname: Occhetta
authors.affiliation: Cardiology Department, Ospedale di Cecina, Azienda USL 6, Livorno, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Mazzocca
authors.affiliation: Cardiology Department, Ospedale Versilia di Camaiore, Lido di Camaiore, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Svetlich
authors.affiliation: Cardiology Department, Ospedali Riuniti Umberto I - GM Lancisi - G Salesi, Ancona, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Scipione
authors.affiliation: Cardiology Department, Ospedale Area Aretina Nord, Arezzo, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Fabiani
authors.affiliation: Cardiology Department, Ospedale Maria Vittoria, Torino, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Giammaria
authors.affiliation: Cardiology Department, Azienda Sanitaria Locale, Rieti; Italy.
authors.forename: Serafino
authors.initials: S
authors.lastname: Orazi
authors.affiliation: Formely, Medtronic BRC, Maastricht, The Netherlands.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Corbucci
keywords: Biventricular Pacing; Catheter Ablation of the Atrioventricular Node; Right Ventricular Pacing; Ventricular Tachycardia