Extended ECG Monitoring in Patients with Hypertrophic Cardiomyopathy: The Tempo-HCM Study

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Current guidelines recommend 24-48 hour Holter monitoring for hypertrophic cardiomyopathy (HCM) patients.
• Shorter monitoring durations may lack sensitivity for detecting arrhythmias.
• Extended ECG monitoring has shown improved arrhythmia detection in other conditions.

Purpose of the Study:

• To evaluate the effectiveness of 30-day extended ECG monitoring in a non-high-risk HCM cohort.
• To compare arrhythmia detection rates between 30-day monitoring and the initial 24 hours.

Main Methods:

• Prospective multicenter study involving 113 non-high-risk HCM patients.
• Utilized a dedicated device for 30-day ECG monitoring.
• Compared arrhythmias detected during 30 days versus the first 24 hours.

Main Results:

• Extended monitoring detected relevant arrhythmias in 63.7% of patients versus 12.4% in the first 24 hours (p < 0.001).
• Non-sustained ventricular tachycardia (NSVT) was the primary driver of this difference (61.1% vs. 8.9%, p < 0.001).
• 21.2% of patients were reclassified to a higher sudden cardiac death (SCD) risk category.

Conclusions:

• Extended ECG monitoring substantially increases arrhythmia detection in HCM patients.
• NSVT is frequently detected in non-high-risk HCM patients with prolonged monitoring.
• Further research is needed to define the role of extended monitoring in SCD risk stratification and AF screening.