Learn More
We used two experimental techniques to study the effect of lidocaine hydrochloride on the early inward transient (sodium) current as it is reflected by the maximum rate of change of action potential phase 0 (Vmax). We assessed the effect of lidocaine on Vmax as Purkinje fibers were slowly depolarized by increasing the extracellular potassium concentration(More)
A major advance in understanding how quinidine depresses maximum upstroke velocity (Vmax) is the Hondeghem-Katzung mathematical model which incorporates voltage-independent rate constants for binding to and unbinding from resting, open, and inactive Na channels, and a voltage shift of -40 mV for the Hodgkin-Huxley h-kinetics of quinidine-associated Na(More)
Of 866 patients enrolled in our multicenter study, 667 performed a low-level exercise test early after myocardial infarction, most before discharge. Excluding seven patients who died before the test could be considered, there was a 14% 1 year cardiac mortality in 192 patients who did not take the test (150 for medical and 42 for logistic reasons) compared(More)
We studied the effects of lidocaine (1-5 mg/liter) on the diastolic currents of sheep Purkinje fibers by the two-microelectrode voltage clamp technique to obtain additional information on how lidocaine decreases the slope of spontaneous diastolic depolarization of mammalian Purkinje fibers. During voltage clamps we measured both the magnitude and time(More)
We enrolled 250 patients with acute myocardial infarction after they had been discharged from the cardiac intensive care unit. Among 236 patients who performed a low-level exercise test just before hospital discharge, 52 (22%) had exercise-induced ST depression of at least 0.1 mV in ECG lead V5, 102 (43%) had ventricular arrhythmias, and 121 (51%) had an(More)
SUMMARY In man, therapeutic doses of imipramine suppress ventricular arrhythmias, and toxic doses can cause severe intraventricular conduction disturbances and cardiac arrest. To determine the cellular mechanisms responsible for these actions, we studied the effects of imipramine hydrochloride at concentrations from 3 x 1<T 8 to 3 x 10~ 6 g/ml on the(More)
  • 1