Evaluation of Electrical and Hemodynamic Effects of Different Pacing Strategies in CRT Candidates

"This intervention involves sequential temporary pacing at five distinct ventricular sites within the same patient during a single electrophysiological study. The pacing sites include:His bundle pacing (HBP),Deep septal pacing (DSP),Left ventricular septal pacing (LVSP),Non-selective left bundle branch pacing (NS-LBBP),Selective left bundle branch pacing (SLBBP).~Each pacing modality is tested under identical hemodynamic and electrophysiological conditions using a fixed output and AV delay. Electrical parameters and acute hemodynamic responses are recorded for each site. The study uses a within-subject crossover design, allowing direct intra-individual comparison of different pacing strategies in patients meeting standard CRT indications. No long-term device implantation is involved during this phase of the study."