Introduction: In patients with atrioventricular(AV) block without sinus node dysfunction, VDD pacemaker implantation has been used for years and was recommended as the primary mode choice. However in the recent years, dual chamber pacemaker systems have gained wider usage because of several reasons like the absence of technological developments in the VDD leads unlike other leads, atrial sensing problems, apical pacing, worries about lead dislocation because of the lack of active fixation, development of sinus node diseases throughout the follow up and need of atrial pacing. In this retrospective analysis, we aimed to investigate the clinical, demographic, echocardiographic features of the patients who had VDD pacemaker implanted as a treatment in the follow up.
Methods: In patients with atrioventricular(AV) block without sinus node dysfunction, VDD pacemaker implantation has been used for years and was recommended as the primary mode choice. However in the recent years, dual chamber pacemaker systems have gained wider usage because of several reasons like the absence of technological developments in the VDD leads unlike other leads, atrial sensing problems, apical pacing, worries about lead dislocation because of the lack of active fixation, development of sinus node diseases throughout the follow up and need of atrial pacing. In this retrospective analysis, we aimed to investigate the clinical, demographic, echocardiographic features of the patients who had VDD pacemaker implanted as a treatment in the follow up.
Results: The mean age of the patients was 66.9±16 (0-97 years).The indications for pacemaker implantation were complete AV block (54.5 %), intermittent block (34.8 %), trifascicular block (2.3 %), postoperative AV block (13.8%) and post – myocardial infarction AV block (0.9%). In most of the patients, left side implantation (cephalic vein in 67.2 %, subclavian vein in 30.4%) was preferred. After a mean follow up of 9.0±4.7 years, when compared to baseline values, a significant decrease in ejection fraction (EF) (54.9±9.8 % vs. 51.0±10.2%, p< 0.0001) and significant increases in left atrium size (4.1±0.5 cm vs. 4.3±0.6 cm, p< 0.0001) and pulmonary arterial systolic pressure (35.6±11.7 mmHg vs. 39.0±10.0 mmHg, p=0.015) were found. 9 patients (2%) had infection of the device wound and all of these patients had their leads extracted. A total of 12 patients (2.7%) had re-implantation due to various reasons. 3 patients (0.7%) had ICD implantation due to low EF. Before pacemaker implantation, 94 patients were found to have coronary artery disease (CAD) and in 56 patients (12.6%) revascularization was performed (44 by-pass surgery, 10 stent implantation, 2 angioplasty). After the pacemaker implantation, 29 patients had the need for coronary imaging and 19 of these (4.2%) were taken into revascularization (12 stent implantation, 5 by-pass surgery, 2 angioplasty). During the follow up, replacement was needed once in 161 patients (36.4 %), twice in 33 patients (7.4%), three times in 2 patients (0,4%). Upgrading was performed in 11 patients (2.5%) (7 DDD, 4 CRT).
Conclusions: Even though VDD pacemaker implantation in the patients who have AV block without sinus node dysfunction was found to be safe, after long term follow up, it causes decrease in EF, increase in left atrial size and pulmonary artery pressure.