A computer-assisted electrocardiographic analysis system: methodology and potential application to cardiovascular toxicology.

An automated analysis of electrocardiographic (ECG) waveforms, based on a precise one-dimensional analysis of features within a generalized computer-enhanced ECG waveform, has been developed in our laboratory. ECG signals are monitored, amplified, and recorded using standard techniques. The recorder output signal is distributed to a microcomputer system. Software developed for the microcomputer slows the signal playback rate and permits operator review of the slowed signal for arrhythmia analysis. The analysis program identifies and superimposes 10-40 individual ECG complexes, depending on the heart rate, and generates an "ensembled" waveform. Operator interaction permits delineation of specific points on the displayed waveform and calculation of heart rate and duration of components within the ECG complex. The primary advantages of this system include (1) extensive automation--computer support decreases analytical time, increases precision, and permits rapid screening of large numbers of animals; (2) enhanced sensitivity--the use of functional parameters should provide a more sensitive index of toxicity than morphological parameters; (3) broad utility--this system provides the capability to utilize a variety of animals, both anesthetized and unanesthetized, ranging in age from fetuses to geriatrics, and permits studies of block as well as longitudinal design; and (4) ease of replication--standardization of equipment and techniques facilitates replication by other laboratories.