Patients
The study protocol was approved by the Institutional Committee on Human Research and Ethics. The study was conducted in compliance with the Declaration of Helsinki. Out of 420 patients with DDD pacemakers who were admitted to cardiology outpatient clinics of two participating hospitals for elective device control between October 7th, 2021 and December 31st, 2021, 177 [mean age, 67.5 ± 14.8 (70) years; 107 men, 70 women] were included in this study. A total of 420 patients with pacemakers, ICDs and CRTs were evaluated. Those with VVI/VDD mode devices, atrial fibrillation/flutter/tachycardia, lead dysfunction or uninterpretable atrial threshold test were excluded and the remaining 177 patients were included in the study.
All patients signed informed consent forms. Patients with atrial fibrillation, atrial tachycardia, very frequent atrial premature beats preventing healthy evaluation of the atrial threshold test, patients in whom pacing continued after the lowest threshold value, patients with higher than measurable threshold values, patients with inconclusive threshold test results, patients with atrial or ventricular lead malfunction were excluded.
Out of 177 subjects, 105 had pacemakers, 20 had ICDs and 52 had CRTs. Overall, 77 patients had Abbott - St Jude Medical, 70 had Medtronic, 20 had Boston -Scientific, 7 had Biotronik and 3 patients had LivaNova - Sorin devices. Demographical and clinical features of the patients, indications for CIED implantation and details of the devices were recorded to be analyzed in this study.