Physiological vs. non-physiological heart pacing as assessed by ultra-high-frequency ECG

Abstract

Abstract Background The dyssynchrony related to permanent cardiac pacing is the main reason for heart failure in some patients. Physiological pacing techniques as His bundle pacing (HBP), left bundle branch pacing (LBBP), and left ventricular myocardial septal pacing (LVSP) were shown to improve clinical outcomes in patients with pacemakers. Due to specific lead placement in the area close to conductive tissue, several different ventricular capture types are possible during them. Method We studied the effect of these pacing modalities on ventricular synchrony using ultra-high-frequency ECG (UHF-ECG), which is a novel tool for ventricular depolarization visualization. Several parameters of dyssynchrony were calculated and compared between studied ventricular capture types. Results We showed ventricular depolarization during nonselective HBP to be equivalent to selective HB pacing. Next, we demonstrated the nonselective HBP in the area below the tricuspid valve leads to the best interventricular synchrony from all other RV pacing locations. We also compared UHF-ECG-derived parameters of ventricular depolarization during HBP, LBBP, and LVSP, and we showed that both pacing types from the left septal area are less physiological than HBP. nsLBBP and sLBBP deteriorate interventricular dyssynchrony, and LVSP leads to less physiological left ventricular depolarization than HBP. Conclusion UHF-ECG is an effective tool that can be used in clinical practice to assess the electrical dyssynchrony caused by cardiac pacing. Furthermore, its real-time implementation allows recognizing between physiological vs. non-physiological pacing during an implant procedure. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health of the Czech Republic