[Surface recording technique of His bundle potential in man]

Area of Science:

• Cardiology
• Electrophysiology
• Medical Instrumentation

Context:

• His bundle electrical activity is crucial for cardiac conduction.
• Current methods for recording His bundle activity are invasive.
• Non-invasive techniques are needed for safer cardiac diagnostics.

Purpose:

• To develop and validate a non-invasive method for recording His bundle electrical activity from the body surface.
• To assess the correspondence between surface-recorded signals and intracardiac His bundle potentials.
• To evaluate the diagnostic potential of this non-invasive technique in patients with conduction abnormalities.

Summary:

• A novel method utilizes bipolar electrocardiogram (ECG) leads (precordial, Frank "x", Frank "z"), high amplification, and digital averaging to record His bundle electrical activity non-invasively.
• Repeatable electrical deflections, termed "B waves", were detected in the PR segment during surface investigations.
• A strong correlation was observed between surface-recorded B waves and intracardiac His bundle (H) waves in patients, confirmed by atrial pacing and pharmacological tests.

Impact:

• This non-invasive technique offers a safer alternative to invasive His bundle recordings.
• It has the potential to improve the diagnosis and management of cardiac conduction disorders.
• The method could enhance the understanding of cardiac electrophysiology and pave the way for new diagnostic tools.