Early Clinical Results with VDD Pacing in Patient with Atrioventricular Block

Abstract

In patients with intact sinus node function and atrioventricular block III(o) VDD pacing with a single pass lead may have advantages compared to conventional DDD systems. The purpose of this study was to evaluate the reliability of a new VDD pacemaker with regard to problems encountered with the implantation and the stability of the atrial sensing potential in the postoperative course. 24 patients (10 male, 14 female; age 61 +/- 17 years) underwent implantation of the Intermedics UNITY 292+07 VDD pacemaker. Patients were analyzed postoperatively with respect to stimulation parameters applied. The mean follow-up was 10+/- 3 months. While early on 23 of 24 patients were paced in a VDD mode, one patient was programmed to the vvi mode due to atrial flutter. One patient died early after aortic valve replacement, while another lost his atrial sensing one month postoperatively. Two patients were reprogrammed to the vvi mode because of atrial arrhythmias. The other 20 patients demonstrated stable atrial sensing potential aside from unchanged ventricular stimulation parameters. No infectious or unchanged ventricular stimulation parameters. No infectious or technical problems were observed. From these results it is concluded that VDD pacing may represent an excellent alternative in patients with intact sinus node function and AV block III(o). The atrial sensing was found to be reliable with the additional technical advantage that the single pass lead is less prone to dislocation than the atrial leads in DDD pacing.

Dual chamber cardiac pacing in children: Single chamber pacing dual chamber sensing cardiac pacemaker or dual chamber pacing and sensing cardiac pacemaker?

“…Intermittent atrial undersensing is common in these pacemakers 11 . Previous studies have demonstrated a gradual decrease in the P wave amplitude during the follow‐up period 12−18 . Our study also demonstrated that in both pacing modes there were significant differences in atrial signal measurements in the period between implantation and the last visit ( P < 0.05).…”

Atrial Signal Amplitude Measurements in VDD Systems According to Body Position

“…Many studies showed stability of P wave amplitude in VDD systems in long‐term follow‐up 3,5‐7,9,14‐16 . However, P wave sensing failure can occur at times during the follow‐up in 5–13% of patients 5‐7,9 .…”

“…Single lead VDD pacing is a reliable method of physiological pacing and an established therapy in patients with atrioventricular (AV) block and normal sinus node function 1‐12 . According to current guidelines it is one of the recommend types of therapy 13 .…”

“…According to current guidelines it is one of the recommend types of therapy 13 . Providing AV synchronous pacing, this single lead technique facilitates and shortens the time of implant and leads to less frequent complications as compared to dual lead systems 3‐5,8 . It is also less expensive 10,11 .…”

“…It is also less expensive 10,11 . However, the variability of atrial sensing of the floating electrode may cause atrial undersensing, 3,5‐7,9,14‐16 which may be symptomatic 17 …”