High-speed Holter ECG analysis--what we have learned.

A system for high-speed quantitative analysis of continuous ECG (Holter) recordings has proved effective in maintaining a measured specificity of 99.67 percent and sensitivity of 99.74 percent. Practical difficulties with common ECG signal artifact, and with unusual QRS complexes, have proved that online operator monitoring of classification accuracy is required. Because of artifactual and physiological variability among patients, Holter analysis of individual recordings is meaningless unless accompanied by an indication of the degree of accuracy of the specific recording. Common definitions of specificity and sensitivity based on results from sample recordings are not sufficient to describe the characteristics of an automated ECG performance on any given recording. A quality assurance program that evaluates both the machine and its operator is discussed.