Ambulatory ECG recordings: a spectrum of technology.

A four-tiered approach to data reduction-observer analysis, semi-automated scanning, automated scanning, and computer applications-of ambulatory electrocardiographic recordings is now possible as a result of refinements in technology. Clinical circumstances, cost, and requirements of the involved institution or laboratory will dictate to what extent more advanced technology is needed. Although computer application will increase the detection sensitivity of ectopic beats, sophisticated, costly systems are still required for the analysis of high-frequency ectopic activity tapes.