(FIT)-Module 1 Lectures: Basic Science and Fundamentals-Sinoatrial and Atrioventricular Nodes and His-Purkinje System (Miller)

Video Transcription

Video Summary

In a session presented by John Miller from the Heart Rhythm Society, the complex mechanisms of sinoatrial (SA) and atrioventricular (AV) nodal conduction, as well as the His-Purkinje system, are discussed. The session aims to cover the anatomy, evaluation, autonomic influences, and potential therapies related to cardiac impulse formation and conduction. A strong grasp of cardiac anatomy and physiology is deemed essential for electrophysiologists today, particularly when performing procedures like ablations, which require precise maneuvering to avoid critical areas and effective placement of pacing electrodes.<br /><br />Miller delves into the intrinsic and extrinsic issues that can impact the function of the sinoatrial node, such as idiopathic degenerative changes, ischemia, and the influence of drugs and metabolic factors. He highlights the significance of evaluating electrical pathways in the heart using electrocardiograms (ECG) and intracardiac recordings to determine if there are signs of conduction issues. In practice, decisions concerning the need for pacemakers are usually straightforward based on ECG and clinical data. However, additional studies such as EP may be necessary when conduction problems endanger heart functionality.<br /><br />The presentation underscores the importance of recognizing different types of AV nodal and His-Purkinje system abnormalities, including first, second, and third-degree sinus exit blocks, brady-tachy syndrome, and dual AV nodal pathways, and provides techniques for testing and analyzing these conditions. Electrophysiologists are reminded that many genetic abnormalities can affect the heart's conduction system, and Miller also touches upon non-pathologic rhythm disturbances that might be mistaken for heart issues. <br /><br />Overall, the session emphasizes the significance of understanding cardiac function to diagnose and treat various potential conduction system disorders effectively.

Keywords

sinoatrial node

atrioventricular node

His-Purkinje system

cardiac conduction

electrophysiology

ablation procedures

pacemaker implantation

electrocardiogram (ECG)

sinus exit block

brady-tachy syndrome

dual AV nodal pathways