60-Hz Ventricular Fibrillation and Pump Failure Thresholds Versus Electrode Area

Fibrillation thresholds and safe leakage current levels are being reexamined and new values of safe current other than the 10 μA are being considered. Values of fibrillation and pump failure thresholds are presented and related to surface area. The surface areas covered range from those found in dye injection and other exploratory catheters (0.224 mm
²
) to the largest endocardial pacing catheter (90 mm
²
). The results indicate that to choose or set a safe current level without regard to surface area or based on one surface area is unrealistic.