Implant failures in conduction system pacing: single centre experience

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Conduction system pacing (CSP) ensures physiological ventricular activation and avoids the dyssynchrony associated with traditional myocardial pacing. New dedicated tools makes it possible to increase procedural success but not yet comparable to myocardial pacing. Objective Retrospective analysis of 3-years CSP implants, focusing on implant failures. Methods From January 2019 to June 2022, 639 CSP implant were performed (91% PMs and 9% ICDs). Single-chamber ICDs implants and devices replacements were excluded from the analysis because the conduction system pacing could not be an option in those cases. Pacing indications were standard with prevalence of AV block (51%); AF with slow ventricular rate 14.5%; sick sinus syndrome 14.5%; ablate&pace 4%; heart failure or cardiomyopathy 14.5%, re-interventions after malfunction of a previous implant 1.5%. Mean age was 78±9 years; 62% were males. Results CSP was successfully achieved in 605 cases (94.6%). In 34 cases lead implant failed. Reasons for failure were "anatomical" in 15 cases (5 due to excessive right atrial enlargement, 5 due to severe pulmonary hypertension; 3 due to scar in the septum and 2 due to stenosis of the venous axis in upgrading procedure) and "technical" in 19 cases (5 due to unacceptable high thresholds, 10 due to uncorrected bundle branch block, 4 due to dislodgment during cutting without reposition). In 52% of the CSP implant failures, an underlying cardiomyopathy or heart failure were documented. Considering CSP failure, the implant was concluded with standard biventricular pacing in 18 cases (in 4 cases the coronary sinus implantation also failed) while 16 implants were concluded with the lead implanted in the septum or apex. Conclusions conduction system pacing is feasible in daily clinical practice; available tools allow to achieve high procedural success rate (94.8% implant success rate in our experience). Procedural failures were 5.2% and were caused by anatomical (44%) or technical reason (56%).