P516Permanent his bundle pacing: conclusions from the one-year experience of a romanian center

Abstract

Abstract Background Long term right ventricular pacing has been associated with an increased risk of heart failure development due to pacing induced cardiomyopathy. Therefore, alternatives of more physiological pacing have been evaluated. Amongst them, His bundle pacing (HBP) has emerged in the past two decades as the most physiological method of ventricular pacing due to synchronous activation of both ventricles through the intrinsic conduction system. Although there is an already consistent experience in the United States, China and western Europe regarding His bundle pacing, some countries in central and eastern Europe have little or no experience in this matter. We present the results of our one-year experience after implementing His bundle pacing in a tertiary cardiac pacing center in Romania. Material and methods Between July 2018 and October 2019, HBP using the current available dedicated delivery system was attempted in 50 patients with permanent cardiac pacing indications. Patient characteristics and procedural results were analyzed during implant and at 3 months, 6 months and 1 year follow-ups. Results The mean age of the patients was 70,14 ± 10,58 years and 58 % were male. The main indication for cardiac pacing was atrioventricular block (66%) and 96 % received a dual-chamber pacemaker. No ventricular back-up leads were used. The acute procedural success (selective or nonselective His bundle capture) was achieved in 40 patients (80%). The rest of the patients received either right ventricular or left bundle branch pacing. Selective His bundle pacing was seen in 15 out of 40 patients, with nonselective His bundle pacing in the rest. The acute His pacing threshold was 1.77 ± 1.06 V at 1 ms, the sensed R wave amplitude was 4.2 ± 2.27 mV and total fluoroscopy time was 15.95 ± 10.9 min. The paced QRS duration was very similar to the baseline QRS duration in patients without bundle branch block and significantly narrower in patients with bundle branch block morphology (126,6 ± 23 ms vs. 95,5 ± 21,65 ms, p < 0,001). The presence of a native QRS complex with a bundle branch block morphology was associated with an increased risk of procedural failure, longer fluoroscopy times and higher capture thresholds. Also, pacing threshold (1,91 ± 1,23 vs. 1,62 ± 0,84 V/1ms , p = 0,4) and fluoroscopy times (21,15 ± 10,35 vs. 10,75 ± 8,85 min, p = 0,002) were lower in the second half of the procedures as the learning curve was achieved. There were no significant changes in pacing and sensing thresholds at 3 months, 6 months and 1 year follow-ups. There was only one case of lead dislodgement a week after the procedure that required reintervention. Conclusion His bundle pacing is feasible and easy to implement in an experienced device implantation center, with a high procedural success rate. Improvement of the procedural parameters is achieved while advancing the learning curve. Proper patient selection could influence the outcomes of the procedure.