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Conduction System Pacing for CRT — EECC MCQ

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ModerateCardiac DevicesConduction System Pacing for CRTEECC

A 68-year-old man with a CRT-D has persistent AF with suboptimal biventricular pacing (BiV pacing 82%). Despite AV nodal blocking agents, his resting ventricular rate is 95 bpm. What is conduction system pacing (CSP) and how might it apply here?

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Correct answer: D — CSP (His bundle pacing or left bundle branch area pacing) delivers pacing via the native conduction system, producing physiological ventricular activation; LBBAP is increasingly used as an alternative to conventional BiV pacing for CRT with advantages in lead stability and narrower paced QRS

Conduction system pacing (CSP) encompasses His bundle pacing (HBP) and left bundle branch area pacing (LBBAP). LBBAP involves placing the pacing lead through the interventricular septum to capture the left bundle branch, producing near-physiological LV activation. Advantages over traditional BiV CRT include: (1) more physiological activation pattern; (2) higher success rates than HBP (which has lead stability issues); (3) lower pacing thresholds; (4) may achieve CRT in patients with failed CS lead placement. The 2021 ESC Pacing Guidelines mention CSP as an emerging alternative (Class IIb), with rapidly accumulating evidence. For this patient with AF and suboptimal BiV pacing, AV node ablation combined with CSP (LBBAP) could provide 100% physiological ventricular pacing.

Reference: ESC (2021): Cardiac Pacing and CRT Guidelines