[Our initial experience in using allapinin in patients with paroxysmal supraventricular tachycardias]. / Pervyi opyt primeneniia allapinina u bol'nykh s paroksizmal'nymi nadzheludochkovymi takhikardiiami.

Twenty one patients with various forms of paroxysmal supraventricular tachycardias (SVT) were treated with allapinine, a new antiarrhythmic drug. Intravenous infusion of allapinine (0.43 mg/kg) arrested the episodes of SVT in none of 7 patients. Oral administration of the drug for short-term treatment (150 mg/day) prevented the artificial induction or spontaneous occurrence of paroxysms in 10 of 16 patients. Thus, the first experience with allapinine shows its potential efficacy in the prophylactic treatment of paroxysmal SVT.

[Effect of a single oral dose of allapinin in patients with chronic ventricular extrasystole]. / Deistvie allapinina pri odnokratnom prieme vnutr' u bol'nykh s khronicheskoi zheludochkovoi ekstrasistoliei.

Effect of a new antiarrhythmic drug allapinin was studied in 21 patients with chronic ventricular extrasystoles by an acute drug test with single oral dose of the drug controlled by 12-hour Holter monitoring. In 9 cases the dose was 50 mg. Maximal total reduction of ventricular ectopic complexes (VEC) per hour was 67 +/- 28% (mean value); in 5 cases (55%) it exceeded 90% of basal level. At peak of action, PQ interval increased by 15%, QRS--by 14%, QT was not significantly changed. In 14 cases the dose was 75 micrograms. Maximal VEC number reduction per hour was on the average 89 +/- 18% and in 12 cases (88%) exceeded 90%. PQ increased by 22%, QRS--by 23% and QT by 9% though JT was not changed (average peak values). It is thus concluded that single oral dose of allapinin has pronounced antiarrhythmic effect in patients with VEC and influences ECG intervals in the way characteristic for class IC antiarrhythmic drugs. The degree of the effect depends on the dose.

[Effect of allapinin after a single intravenous administration to patients with chronic ventricular extrasystole]. / Deistvie allapinina pri odnokratnom vnutrivennom vvedenii bol'nym s khronicheskoi zheludochkovoi ékstrasistoliei.

Clinical assessment of a new antiarrhythmic drug, allapinin, was carried out in 42 patients with chronic ventricular extrasystoles. Single intravenous doses were effective where they exceeded 0.32 mg/kg. Doses above 0.42 mg/kg were regularly associated with side effects, such as dizziness or, less commonly, diplopia. The 0.39 mg/kg dose produced an antiarrhythmic effect in 61% of patients, whose PQ interval was lengthened by 23%, and the QRS complex, by 18%, while QTc duration remained unchanged. Heart rate and arterial blood pressure were virtually unchanged, either. The peak of antiarrhythmic effect fell to the second postadministration hour, and the effect persisted within an average of 7.6 hours. Therefore, allapinin appears to be a potent quinidine-like agent.