Hypertrophic cardiomyopathy (HCM) is a common heart condition characterized by thickening of the heart muscle, which can lead to arrhythmias and sudden cardiac death. Early detection and management of arrhythmias is crucial for patients with HCM. However, arrhythmias can be difficult to detect using traditional electrocardiogram (ECG) monitoring. Extended ECG monitoring, also known as ambulatory ECG monitoring, has been shown to significantly increase arrhythmia detection in patients with HCM. In this article, we will explore the benefits of extended ECG monitoring in the detection and management of arrhythmias in HCM.
A recent study known as TEMPO-HCM has found that extended electrocardiogram (ECG) monitoring can detect more arrhythmias in patients with hypertrophic cardiomyopathy (HCM) compared to the standard 24-48 hour period. The study was presented in a session at the European Heart Rhythm Association (EHRA) 2023 meeting in Barcelona, Spain. Data has shown that approximately 20-30% of patients with HCM have nonsustained ventricular tachycardia (NSVT), which increases the risk of sudden cardiac death. The standard for monitoring these arrhythmias in HCM patients has been 24-48 hour Holter monitoring. However, extended ECG monitoring has been shown to be more effective in improving detection of atrial fibrillation in patients with cryptogenic stroke or after pulmonary vein isolation. The TEMPO-HCM study aimed to determine whether extended ECG monitoring in HCM patients using a continuous recording system would identify a significantly greater number of clinically relevant arrhythmias than shorter measurements.
The study enrolled 100 HCM patients from 5 hospitals who underwent extended ECG monitoring for 30 days using a dedicated device. Upon analysis, extended ECG monitoring detected a higher incidence of clinically relevant arrhythmias than the 24-hour monitoring (65% vs. 11%; P < .001), with most patients having NSVT detected in 62% of patients across 30 days compared with 8% in the first 24 hours. Extended monitoring data led to more than 1-in-5 patients being reclassified to a higher risk category, leading to 13 additional patients in which an implantable cardioverter defibrillator (ICD) may be considered and 7 additional patients in which an ICD should be considered. Extended monitoring also detected four more cases of atrial fibrillation than 24-hour monitoring, including three patients who did not have a prior diagnosis of arrhythmia. Although the difference between the study periods did not achieve statistical significance, the study suggests that extended monitoring has potential benefits for atrial fibrillation screening and justifies further research.
Juan Caro Codon from Led Paz University Hospital, who led the TEMPO-HCM study, cautioned regarding the significance of NSVT episodes during prolonged ECG monitoring, noting that if a risk factor is extremely prevalent among certain patient populations, it is possible that it does not adequately discriminate the true risk of sudden cardiac death. He emphasized that more complete phenotyping of the arrhythmic profile of a specific patient may aid in risk stratification, where extended ECG monitoring may also help. However, further research is needed before it is ready for clinical practice.
In conclusion, extended ECG monitoring is essential for detecting arrhythmias in patients with hypertrophic cardiomyopathy. This monitoring technique involves wearing a portable electrode device that records the heart’s electrical activity continuously for several days or weeks. With extended ECG monitoring, doctors can detect subtle changes in a patient’s heart rhythm, which can help them provide more targeted and personalized treatment. By extending the duration of monitoring, healthcare professionals can reduce the risk of missed arrhythmia cases and improve their early detection. Ultimately, these benefits can improve the quality of life and outcomes for patients with hypertrophic cardiomyopathy.
