Work

Characterization of spontaneous termination of sustained ventricular tachycardia associated with coronary artery disease

Year: 1991

Type: article

Abstract: To characterize the change in cycle length and QRS morphology before spontaneous termination of sustained ventricular tachycardia (VT), electrocardiograms were recorded and VT cycle length measured for the periods 31 to 21 and 11 to 1 beats before termination in 55 episodes from 28 patients with coronary artery disease. Beats 31 to 21 were designated as a period of stable arrhythmia and served as a reference for changes occurring just before termination. Forty-four episodes of VT occurred in the setting of antiarrhythmic drug therapy; 11 episodes occurred in patients not treated with antiarrhythmic drugs. Variability in cycle length was indexed by the standard deviation of the mean cycle length and by the percentage of consecutive cycles varying by ≥ 40 ms (% ≥ 40 ms). There was greater variability just before termination (standard deviation of the mean cycle length, 25.8 ms; % ≥ 40 ms, 16.7%) than during the stable period (standard deviation of the mean cycle length, 8.5 ms; % ≥ 40 ms, 5.4%; p < 0.001 for both). This was true irrespective of antiarrhythmic drug use, although the differences in the standard deviation of the mean cycle length for beats 11 to 1 and for beats 31 to 21 were greater for the antiarrhythmic drug group (29.6 vs 8.9 ms, p < 0.001) than for the group not receiving antiarrhythmic drugs (11.0 vs 6.7 ms, difference not significant). No specific patterns of cycle length variability characteristic of VT termination were found. A change in QRS morphology occurred before termination in only 4 (7%) episodes of VT. In all, (1) cycle length variability increases immediately before spontaneous VT termination, although marked variability may occur without termination; (2) antiarrhythmic drugs may enhance the increase of cycle length variability at the time of termination; (3) distinct patterns of cycle length variability were infrequently seen at termination; and, (4) a change in VT morphology before termination is rare. These results may have implications for validating computer models of VT termination, for designing sensing criteria for antitachycardia devices and for increasing our understanding of antiarrhythmic drug action.

Source: The American Journal of Cardiology

DOI: 10.1016/0002-9149(91)90098-6

Authors: David J. Callans, Francis E. Marchlinski

Institutions: Hospital of the University of Pennsylvania, University of Pennsylvania

Language: English

Topic: Cardiac Arrhythmias and Treatments

Subfield: Cardiology and Cardiovascular Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,380