ABSTRACT
Following the increasing use of tricyclic antidepressants, numerous side effects of these drugs are reported, e.g. ECG changes and cases of "sudden death". Because of the fact that haemodynamic studies in man and studies on the possible correlation between the structure of these drugs and their negative inotropic effect are lacking, we have investigated the influence on myocardial contractility of cat papillary muscle induced by impramine and dimetacrin as well as their desmethyl compounds (n = 42). Furthermore, the effects of i.v. administration of imipramine and dimetacrine on cardiovascular functions were investigated in 18 patients at cardiac catheterization. In addition, four patients were studied during ergometric exercise before and 45 min after injection of both drugs. Finally, fluorimetric determination of norepinephrine plasma concentrations were carried out in 8 patients.