Potassium efflux from myocardial cells induced by defibrillator shock.
نویسندگان
چکیده
A transient, dose-dependent cardiac depression was produced by defibrillator shocks in an isolated, working canine heart preparation perfused with oxygenated arterial blood from a support dog. Accompanying this depression was an efflux of potassium (K+), forced out of the myocardial cells by the passage of defibrillating current. The transient increase in extracellular K+ concentration was recorded graphically in the venous outflow. It was found that 5-msec rectangular wave shocks, from three to ten times defibrillatory current threshold, released dose-related pulses of K+. It is concluded that because K+ is a myocardial depressant, at least part of the myocardial depression after defibrillation is caused by the release of K+ from the myocardial cells.
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عنوان ژورنال:
- Medical instrumentation
دوره 20 3 شماره
صفحات -
تاریخ انتشار 1986