(FIT)-Module 2 Lectures: Invasive Diagnosis and Treatment Part 1-Principles of Entrainment

Video Transcription

Video Summary

The session focuses on the principles of entrainment for mapping ventricular tachycardia. Bill Stevenson from Vanderbilt University Medical Center explains that modern electroanatomic mapping allows for detailed visualization of reentry circuits in scar-related areas, typically forming figure-eight or double-loop circuits around an isthmus. Activation maps may not always clearly identify the isthmus but can suggest its presence, which can aid in targeting ablation effectively to terminate VT.<br /><br />Entrainment is described as the continuous resetting of a reentry circuit, and its mapping helps identify the circuit's components without requiring a full activation map. By pacing slightly faster than the tachycardia, clinicians can study the site's influence on the reentry circuit, checking for pacing capture and assessing the post-pacing interval to determine proximity to the circuit.<br /><br />Concealed fusion during entrainment pacing, where the morphology of QRS complexes remains unchanged, indicates that pacing is close to the reentry circuit, often within a narrow isthmus. Identifying the exact part of the circuit aids in effective ablation. The session also highlights that complex scar-related arrhythmias often show multiple potential pitfalls, emphasizing the value of combining entrainment and activation mapping for successful intervention.

Keywords

entrainment

ventricular tachycardia

electroanatomic mapping

reentry circuit

isthmus

activation map

ablation

concealed fusion