Variable interatrial conduction illustrated in a hypertrophic cardiomyopathy population.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Hypertrophic cardiomyopathy (HCM) is linked to a high incidence of atrial fibrillation.
• Patients with HCM show prolonged P-wave duration, suggesting atrial conduction abnormalities.
• Previous research noted P-wave morphology changes in paroxysmal atrial fibrillation.

Purpose of the Study:

• To compare P-wave morphology in hypertrophic cardiomyopathy (HCM) patients versus matched controls.
• To investigate the nature of atrial conduction alterations in HCM.
• To explore the relationship between P-wave duration and interatrial conduction.

Main Methods:

• Included 65 patients with HCM and 65 matched controls.
• Recorded 5-minute 12-lead ECGs for all participants.
• Transformed ECG data to orthogonal leads for signal-averaged P-wave analysis.

Main Results:

• HCM patients had significantly longer P-wave duration (149 ms) than controls (130 ms).
• Interatrial conduction block was observed in both groups, but more severe in HCM patients.
• P-wave changes were most pronounced in Leads Y and Z.

Conclusions:

• Prolonged P-wave duration in HCM patients is likely due to increased interatrial conduction block.
• Interatrial conduction abnormalities contribute to the observed ECG findings in HCM.
• Findings highlight the role of interatrial block in HCM pathophysiology.