EVALUATION OF CERTAIN ANTIHISTAMINICS FOR USE IN AURICULAR FIBRILLATION

1. The isolated auricle technique of Dawes has been used to study the action of a series of antihistamine compounds on the myocardial refractory period. The antihistaminics studied prolong the refractory period at concentrations lower than that required by quinidine. Diphenhydramine appeared worthy of clinical trial in patients with auricular fibrillation. 2. Fibrillation or flutter has been evoked in the isolated auricle preparation by a localized traumatic infarct or by aconitine. Quinidine and diphenhydramine can produce a sudden conversion to a slow rhythm in these preparations.