Atrioventricular block. Mechanism, clinical presentation, and therapy

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Atrioventricular (AV) block and bifascicular block are common cardiac conduction abnormalities.
• Understanding their mechanisms is crucial for effective patient management.
• His bundle electrocardiography offers insights into the electrical activity within the heart's conduction system.

Purpose of the Study:

• To review the underlying mechanisms of AV block and bifascicular block.
• To elucidate the role of His bundle electrocardiography in precisely locating the site of AV block.
• To discuss the clinical manifestations, therapeutic strategies, and indications for permanent pacing in patients with AV block.

Main Methods:

• Review of existing literature on cardiac electrophysiology and conduction disorders.
• Analysis of the diagnostic utility of His bundle electrocardiography.
• Synthesis of information regarding clinical presentations and treatment guidelines for AV block.

Main Results:

• Detailed explanation of the pathophysiological mechanisms leading to AV block and bifascicular block.
• Demonstration of His bundle electrocardiography's effectiveness in differentiating sites of block within the AV junction.
• Comprehensive overview of current therapeutic approaches, including pharmacotherapy and device implantation.

Conclusions:

• Accurate localization of AV block using His bundle electrocardiography aids in guiding therapeutic decisions.
• Management strategies for AV block should be tailored to the specific type and severity of conduction delay.
• Permanent pacing is indicated in select cases of AV block to restore appropriate atrioventricular synchrony and prevent symptoms.