What is the purpose of a Holter monitor?

The purpose of a Holter monitor is to continuously record heart rhythms over an extended period, typically ranging from 24 to 48 hours. This device is particularly valuable for capturing intermittent arrhythmias or other abnormalities in heart rhythms that may not be detected during a standard EKG, which only provides a brief snapshot of cardiac activity at a single moment in time. The continuous monitoring allows for a more comprehensive evaluation of the heart’s activity throughout daily activities and even during sleep, making it an essential tool in diagnosing conditions like atrial fibrillation or other rhythm disturbances.

In contrast, while measuring the heart's electrical activity during exercise is important in some contexts, that is specifically the role of a stress test, not a Holter monitor. The Holter monitor is not designed to detect structural heart abnormalities, which typically require imaging techniques like echocardiography or MRI.