Correlation between the signal-averaged electrocardiogram from Holter tapes and from real-time recordings

Readings from a real-time electrocardiograph, a device that measures the heart's electrical output, were compared to recordings from a Holter monitor, a tiny portable electrocardiograph which records heart activity of the person wearing the device, and close correlation between the results of both methods was obtained. Although the Holter systems have trouble with high frequencies, Holter analysis may be very beneficial in that it can record a number of different parameters on the same tape, which is important in analyzing abnormal heartbeats (arrhythmias). It may prove useful in observing transient ischemia (periods of insufficient oxygen to the heart) or spontaneous ventricular fibrillation (erratic contraction of the lower left heart chamber). Diagnostic accuracy using criteria for real-time systems is clinically acceptable for use until specific Holter criteria are established.