THE HEMODYNAMIC-EFFECTS OF KETANSERIN VERSUS DIHYDRALAZINE IN SEVERE EARLY-ONSET HYPERTENSION IN PREGNANCY

Objective To compare the haemodynamic efficacy of ketanserin (a select ive serotonin(2)-receptor blocker) with dihydralazine in the managemen t of severe early-onset hypertension in pregnancy. Design Subgroup ana lysis within a randomised prospective multicentre trial to compare hae modynamic effects as measured by pulmonary artery catherization. Setti ng Departments of Obstetrics and Gynaecology and Intensive Care Medici ne, Free University Hospital, Amsterdam and Sophia Hospital, Zwolle. P articipants Thirty-one women with a diastolic blood pressure > 110 mmH g and a gestational age between 26 and 32 weeks. Results The antihyper tensive efficacy of both drugs was comparable. Dihydralazine significa ntly increased cardiac output (P < 0.01), while ketanserin induced onl y minor changes in cardiac output. Systemic vascular resistance decrea sed in both groups, but the decrease was significantly more pronounced with dihydralazine compared with ketanserin. Ketanserin induced a sig nificant but not clinically relevant increase in heart rate (P < 0 01, while dihydralazine caused marked tachycardia (P < 0.005). Left ventr icular stroke work index was reduced to similar values in both groups. Conclusions The antihypertensive profile of ketanserin is characteris ed by an early and gradual reduction of blood pressure in combination with a moderate decrease in systemic vascular resistance and no signif icant change in cardiac output. Dihydralazine causes market tachycardi a resulting in a considerable increase in cardiac output.