Characteristics of a large sample of candidates for permanent ventricular pacing included in the Biventricular Pacing for Atrio-ventricular Block to Prevent Cardiac Desynchronization Study (BioPace)

Aims: The general clinical profile of European pacemaker recipients who require predominant ventricular pacing (VP) is scarcely known. We examined the demographic and clinical characteristics of the 1808 participants (out of 1833 randomized patients) of the ongoing Biventricular Pacing for Atrio-ventricular Block to Prevent Cardiac Desynchronization (BioPace) study. Methods and results: BioPace recruited patients between May 2003 and September 2007 predominantly in European medical centres. We analysed demographic data and described clinical characteristics and electrophysiological parameters prior to device implantation in 1808 enrolled patients. The mean age ± standard deviation (SD) of the 1808 patients was 73.5 ± 9.2 years, 1235 (68%) were men, 654 (36%) presented without structural heart disease, 547 (30%) had ischemic, 355 (20%) hypertensive, 146 (8%) valvular, and 102 (6%) non-ischemic dilated cardiomyopathy. Mean left ventricular ejection fraction was 55.4 ± 12.3%. The main pacing indications were (a) permanent and intermittent atrioventricular (AV) block in 973 (54%), (b) atrial fibrillation with slow ventricular rate in 313 (17%), and (c) miscellaneous bradyarrhythmias in 522 (29%) patients. Mean QRS duration was 118.5 ± 30.5 ms, left bundle branch block was present in 316 (17%), and atrial tachyarrhythmias in 426 (24%) patients. Conclusion: To the best of our knowledge, this sample is a representative source of description of the general profile of European pacemaker recipients who require predominant VP. Patients' characteristics included advanced age, predominantly male gender, preserved left ventricular systolic function, high-grade AV block, narrow QRS complex, and atrial tachyarrhythmias, the latter being present in nearly one-fourth of the cohort