Arrhythmia monitoring in HCM patients is used not only for determining risk of sudden death and potential need for an implantable defibrillator, but also for detecting atrial fibrillation (AFib) and implementing anti-coagulation for stroke prevention.

A recent paper provides an overview of the usefulness of arrhythmia monitoring in patients with HCM. 

THERE ARE DIFFERENT TYPES OF EVENT MONITORS

There are several varieties of event monitor available: some are used for a day or two, some for a couple of weeks, and some implantable devices such as implantable loop recorders can be used to record rhythm abnormalities for several years.

WHEN IS MONITORING APPROPRIATE?

The 2020 AHA/ACC Guidelines recommend arrhythmia monitoring at initial evaluation and then every 1 or 2 years thereafter. Extended monitoring is also recommended for patients with palpitations or lightheaded episodes in order to ascertain and treat the cause.

MONITORING FOR ATRIAL FIBRILLATION

This paper highlights the fact that patients with HCM who have Afib risk factors should undergo an initial screening for AFib and then repeat arrhythmia monitoring every 1 to 2 years thereafter.

IMPORTANT NOTE -The prevalence of AFib in HCM is 4 to 6 times higher than in the general population. Documented AFib of more than 24 hours duration requires lifelong treatment with anti-coagulants in order to avoid a thromboembolic stroke.

MONITORING FOR NON-SUSTAINED VENTRICULAR TACHYCARDIA (NSVT)

Episodes of NSVT found during monitoring, especially when looked at in conjunction with other risk factors, may support the recommendation of an implantable defibrillator.