Use of procainamide in patients with the Wolff-Parkinson-White syndrome to disclose a short refractory period of the accessory pathway.
Like ajmaline, procainamide can be used to identify patients with the Wolff-Parkinson-White syndrome who have a short refractory period of the accessory pathway in an anterograde direction. Procainamide given intravenously in a maximal dose of 10 mg/kg body weight over a 5 minute period during sinus rhythm produced complete anterograde block in the accessory pathway in 20 of 39 patients. An electrophysiologic investigation performed 24 to 48 hours later revealed that in 19 of the 20 patients the effective refractory period of the accessory pathway was 270 ms or greater. In 18 of the 19 patients not exhibiting anterograde block in the accessory pathway, the refractory period was less than 270 ms. When ajmaline was compared with procainamide in the same patients, 100 mg of procainamide had approximately the same effect as 10 mg of ajmaline. The use of intravenous procainamide is a reliable and rapid method of identifying patients with the Wolff-Parkinson-White syndrome who may be at risk for circulatory insufficiency or sudden death in case of atrial fibrillation.
D000293:Adolescent; D000328:Adult; D000368:Aged; D000404:Ajmaline; D002648:Child; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D011342:Procainamide; D014927:Wolff-Parkinson-White Syndrome / Q000175:diagnosis*
D000404:Ajmaline; D011342:Procainamide