Imipramine의 혈중농도와 심전도 영향

The Plasma Concentrations of Imipramine Hydrochloride and Electrocardiographic Effects

The authors conducted a study on the effects of blood pressure and electrocardiograph of imipramine hydrochloride. Twenty DSM-III diagnosed major depressive patients were administered imipramine orally. The blood pressures were obtained three times during treatment. Although orthostatic hypotension did not produce statistically significant results, it lead to termination of the drug treatment for 1 subject. The standard 12-lead ECG tracing was obtained three times and the plasma concentration was measured two times during treatment. The results on examinations were as follows : 1) Heart rates were increased with plasma imipramine and desmethylimipramine concentrations in the range of 0-50ng/ml, 50-100ng/ml(p<0.01) ， 100-150ng/ml(p<C0.05). 2) There was no significant difference between PR interval and plasma imipramine and desmethylimipramine concentrations. 3) QRS intervals were prolonged with plasma imipramine and desmethylimipramine concentrations in the range of 0-50ng/ml(p<0.05), 50-100ng/ml, 100-150ng/ml(p<C0.01). 4) QTc interval was prolonged with plasma imipramine and desmethylimipramine concentration in the range of 0-50ng/ml(p〈0.05). 5) T wave amplitudes were lowered with plasma imipramine and desmethylimipramine concentrations in the range of 0-50ng/ml, 100-150ng/ml ( p<C0.05), 50-100ng/ml ( p<C0.0l). The above results suggest that imipramine should be used cautiously or avoided in patients with ECG abnormality or heart disease because of the increase in heart rate, QRS, QTc interval and the decrease in T wave amplitude with lower plasma imipramine and desmethylimipramine concentrations.