Influence of test site on ventricular fibrillation threshold.

An influence of VFT test site location on measured values of VFT was demonstrated in dogs with coronary occlusions, in dogs with localized areas of short recovery properties induced by warm thermal lesions, and with a computer simulation of fibrillation threshold. Under these experimental conditions VFT did not significantly change from control values when the measurement was made at a site distant to the lesion. Differences in the temporal relationship of time of recovery following application of VFT test stimuli to various locations are probably responsible for the observed differences in effects of lesions on VFT measured at these sites.