(FIT)-Module 2 Lectures: Invasive Diagnosis and Treatment Part 1-Techniques of Differentiating SVT Mechanisms

Video Transcription

Video Summary

Greg Michaud from Vanderbilt University discusses the diagnosis of paroxysmal supraventricular tachycardia (PSVT), focusing on distinguishing between AV node re-entry (AVNRT), orthodromic atrioventricular reentrant tachycardia (AVRT), and atrial tachycardia (AT). AVNRT is identified as the most common form of PSVT, often recognizable by a characteristic 12-lead ECG pattern where P waves create pseudo R' or pseudo S waves due to their overlap with the QRS complex. AVNRT and typical forms of AVRT depend on the AV node for retrograde conduction, which helps differentiate them from AT. Michaud explains various pacing maneuvers and observations, such as looking for dual pathways and evaluating anterograde and retrograde conduction during sinus rhythm. The use of ventricular pacing, the presence of bundle branch blocks, and their effect on the VA intervals are key diagnostic indicators. He emphasizes that obtaining a systematic understanding of sinus rhythm and pacing observations is crucial for accurate diagnosis. Moreover, observations such as tachycardia initiation and termination details and interpreting tachycardia wobbles and cycle lengths play a significant role in diagnosis. His lecture is rooted in practical applications for real-life scenarios and exam preparation, highlighting the importance of recognizing patterns and conducting systematic evaluations during sinus rhythm and pacing to accurately diagnose the type of PSVT.

Keywords

Paroxysmal Supraventricular Tachycardia

PSVT

AV Node Re-entry

AVNRT

Orthodromic Atrioventricular Reentrant Tachycardia

AVRT

Atrial Tachycardia

12-lead ECG

Pacing Maneuvers

Retrograde Conduction

Bundle Branch Block

Tachycardia Diagnosis