Bhorat I E, Naidoo D P, Rout C C, Moodley J
Department of Obstetrics and Gynecology, University of Natal, Durban, South Africa.
Am J Obstet Gynecol. 1993 Apr;168(4):1292-6. doi: 10.1016/0002-9378(93)90383-t.
Our aim was to assess the impact of beta-adrenergic blockade during the peripartum period on the previously observed high incidence of ventricular arrhythmias in eclamptic parturients.
An open, randomized comparison of intravenous labetalol versus dihydralazine was conducted in 40 eclamptic subjects in the peripartum period. Cardiac rhythm was assessed by blinded analysis of a 24-hour Holter record by means of the Lown classification of arrhythmias.
There was a significantly higher incidence of serious ventricular arrhythmias in patients receiving dihydralazine (81%) than in those receiving labetalol (17%, p < 0.0001). Patients receiving labetalol showed a significant decrease in mean heart rate (p < 0.0001), whereas patients receiving dihydralazine showed a significant increase (p < 0.0001).
The introduction of beta-adrenergic blockade into peripartum hypertensive management of eclampsia significantly reduced the incidence of dangerous ventricular arrhythmias. Myocardial oxygen supply/demand ratio may be improved by beta-blockade.
