Clinical use of automatic pacemaker algorithms: results of the AUTOMATICITY registry.

AIMS: Follow-up of the ever-increasing numbers of patients with implantable cardiac devices places a heavy burden on clinical departments. Device automaticity may alleviate the follow-up burden by minimizing the time for physician involvement. The aim of the prospective, multicentre AUTOMATICITY registry was to examine the performance of a subset of programmed automatic algorithms during patient follow-up and their acceptance by implanting physicians. METHODS AND RESULTS: The clinical use of automatic algorithms from the Insignia pacemakers (PM; Boston Scientific, St Paul, MN, USA) was evaluated: atrial and ventricular AutoSense (sensitivity adjustment), ventricular Automatic Capture (threshold verification and output setting), AutoLifeStyle (sensor settings adjustment). The objective of the study was to assess the reprogramming rates within 12 months of implant, the reasons for reprogramming and relationship to adverse events. A total of 960 patients were enrolled in the study. The proportion of patients free from any algorithm reprogramming at 12 months was 86.1%. A total of 2736 algorithms were activated at enrolment, with 156 (5.7%) being reprogrammed in 115 patients at 12 months for any reason. Forty-nine reprogrammings (1.8%) were unintentional or related to changes in device settings such that the algorithm was no longer available, 33 (1.2%) were due to suspected sensing issues, and 22 (0.8%) were assumed related to the algorithm. The individual 12-month reprogramming-free rates were: ventricular AutoSense 94.3%, Atrial AutoSense 93.3%, AutoLifeStyle 93.9%, and Automatic Capture 95.9%. CONCLUSION: The results of the AUTOMATICITY registry show that automatic measurement of key settings and automatic adjustment to optimal programming is feasible and safe. The simplicity of PM follow-up and avoidance of frequent reprogramming may contribute to a more effective use of hospital time and resources.

Impact of atrial prevention pacing on atrial fibrillation burden: primary results of the Study of Atrial Fibrillation Reduction (SAFARI) trial.

BACKGROUND: The role of atrial-based pacing algorithms in preventing atrial fibrillation (AF) remains controversial. The inconsistent results noted in previous trials may be due in part to differences in endpoints, pacing algorithms, and study design. SAFARI, a worldwide, prospective, randomized clinical trial, was designed to address these issues and to evaluate the safety and efficacy of a suite of prevention pacing therapies (PPTs) among patients with paroxysmal AF. METHODS AND RESULTS: Patients who met standard pacemaker indications and documented symptomatic AF were implanted with a pacemaker (Vitatron Selection 9000). At 4 months, only patients with documented AF despite dual-chamber pacing were randomized to PPTs ON or PPTs OFF and followed for 6 months. Incidence of permanent AF and change in AF burden were compared between the two groups. Among the 555 patients enrolled, 240 had AF burden at 4 months and were randomized. The risk of developing permanent AF was similar in both groups (0 in the PPTs ON group vs. 3 in the OFF group). However, there was a significant reduction in AF burden between baseline and 10-month follow-up in the ON group compared with the OFF group (median decrease of 0.08 hours/day vs no change, P = .03). CONCLUSION: Among patients with paroxysmal AF and standard bradycardia indications, PPTs are safe and associated with less AF burden compared with conventional pacing.