[Verification of therapeutic levels of procainamide and N-acetyl- procainamide in ventricular arrhythmia].

Therapeutical efficacy was clinically evaluated in 21 patients with ventricular cardiac arrhythmias. The drug was given orally with preceded intramuscular dose. Therapeutic effect was verified by the measurements of procainamide and N-acetylprocainamide concentrations in blood serum to determine the minimal effective concentration of the drug required to obtain satisfactory antiarrhythmic effect. Procainamide proved effective in cardiac arrhythmias in 14 patients (66.7%) with statistical significance in the acute myocardial infarctions; blood serum procainamide plus N-acetylprocainamide levels being were below the therapeutical range. The poor correlation of the dose of the drug and respective procainamide, N-acetylprocainamide concentrations in blood was observed. Relationship of the therapeutical effects blood serum level of the drug should be estimated basing of the assays of both procainamide and N-acetylprocainamide .