The cardiac conduction system: A narrative review

Area of Science:

• Cardiovascular Physiology
• Cardiac Electrophysiology
• Anatomy

Background:

• The cardiac conduction system (CCS) is a complex network responsible for initiating and coordinating heart electrical activity.
• Its function relies on specialized tissues, cellular heterogeneity, and intercellular coupling.
• A comprehensive understanding is crucial for clinical applications and computational modeling.

Purpose of the Study:

• To provide a multiscale description of the human CCS by synthesizing anatomical, histological, electrophysiological, and imaging evidence.
• To consolidate dispersed insights into a unified framework for reference.
• To highlight the importance of CCS understanding for clinical decision-making and cardiac modeling.

Main Methods:

• Literature review synthesizing anatomical, histological, electrophysiological, and imaging data.
• Multiscale description of CCS components from sinoatrial node to His-Purkinje system.
• Integration of experimental and conceptual findings.

Main Results:

• Detailed description of the sinoatrial node as a protected pacemaker complex.
• Characterization of interatrial conduction pathways.
• Explanation of atrioventricular node's role in physiological delay.
• Description of the His-Purkinje system for rapid ventricular activation.
• Identification of Purkinje-ventricular junction as a critical site for excitation and potential delay.

Conclusions:

• An integrated understanding of the CCS is essential for optimizing cardiac pacing therapies.
• Accurate CCS knowledge supports the development of patient-specific cardiac digital twins.
• This review serves as a reference for clinicians, researchers, and engineers in cardiac electrophysiology and modeling.