Cardiovascular effects of mianserin--a comparative study with amitriptyline and a placebo in healthy subjects

The cardiovascular effects of a tricyclic (amitriptyline) and a tetracyclic (mianserin) antidepressant were compared with those of a placebo in a double-blind randomized group-comparative trial stratified for sex in 18 healthy volunteers. The dose of the test preparations was gradually increased to therapeutic level. Duration of treatment was 8 days. Neither test drug affected objective physical condition, intraocular pressure, blood variables or urinalysis, and the effect on blood pressure was found to be negligible. No impressive differences of untoward cardiac effects between the test preparations could be demonstrated. However, the prolongation of the pre-ejection period in amitriptyline-treated males, indicating a negative effect on myocardial contractility, and the reduction of the left ventricular end-systolic volume by mianserin, probably through increasing the ejection fraction, are observations of possible clinical relevance. They lend further support to the assumption that therapeutic doses of tricyclic antidepressants may produce untoward cardiac effects whereas the tetracyclic mianserin seems devoid of such unwanted properties.