Antiarrhythmic and electrophysiological effects of CH-200.
A new antiarrhythmic drug CH-200, 5-phenacyl-thieno[3,2-c]yridinium, was compared with procainamide and lidocaine in a two-stage coronary ligation arrhythmia model for its efficacy and electrophysiological properties. CH-200 suppressed arrhythmia in beagle dogs more effectively than did procainamide and lidocaine. The antiarrhythmic effects of CH-200 and procainamide developed slowly and lasted longer than those of lidocaine. Electrophysiological studies with CH-200 showed that it decreased max dV/dt of the action potential. This effect was dependent on the heart rate: the higher the rate, the stronger the effect. CH-200, procainamide and lidocaine prolonged the effective refractory period and this effect seemed to be responsible for suppressing the arrhythmia after coronary ligation. CH-200 and procainamide increased the frequency of ventricular pacemaker activity, while lidocaine decreased it. These effects appear to be unimportant for the antiarrhythmic effects.
D000098:Acetophenones / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D000889:Anti-Arrhythmia Agents; D001145:Arrhythmias, Cardiac / Q000503:physiopathology; D003331:Coronary Vessels / Q000502:physiology; D004285:Dogs; D004558:Electric Stimulation; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D008012:Lidocaine / Q000494:pharmacology; D008026:Ligation; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D008839:Microelectrodes; D009200:Myocardial Contraction / Q000187:drug effects; D011342:Procainamide / Q000494:pharmacology; D011726:Pyridinium Compounds / Q000494:pharmacology*
D000098:Acetophenones; D000889:Anti-Arrhythmia Agents; D011726:Pyridinium Compounds; C014895:CH 200; D008012:Lidocaine; D011342:Procainamide