OC17.01: Effect of antihypertensive therapy on pre‐ and postnatal cardiovascular parameters in hypertensive disorders of pregnancy: a human and animal model

This study aimed to assess the effects of antihypertensive therapy (AT) on cardiovascular (CV) parameters in women with hypertensive disorders of pregnancy (HDP) and in a pre-eclamptic rat model. We prospectively evaluated CV parameters in singleton pregnancies with HDP compared to healthy controls. Assessment was conducted via USCOM1A and arteriograph before and after initiation of AT with α-methyldopa as well as 1 week, 3-6 and 12 months postpartum. In the pre-eclamptic rat model maternal hemodynamics were measured invasively, blood pressure (BP) was monitored using telemetry and cardiac compliance assessed via echocardiography. 238 women were included (56 gestational hypertension (GH), 76 pre-eclampsia (PE); 106 controls). There was significant impairment of cardiac output (CO) (PE p<0.001), augmentation index (AiX) (p<0.001) and systemic vascular resistance (SVR) (p < 0.001) in women with HDP before initiation of AT compared to controls. After initiation of AT, there was significant improvement of SVR (difference (D) -0.085, p = 0.005), CO (D 0.382, p = 0.021) and AiX (D 9.314, p = 0.017) in women with GH. No significant changes in CV parameters were found in PE patients after treatment with α-methyldopa (p>0.05 for all). CV parameters improved significantly after delivery but without lasting impact of AT postpartum. In the rat model, prenatal treatment with α-methyldopa and Nifedipine reduced BP but Labetalol did not (MAP (mmHg): PE 160.80 ± 3.85; PE+α-methyldopa 145.01 ± 3.71; PE+Nifedipine 122.08 ± 5.62; PE+Labetalol: 163.12 ± 3.12). Despite antihypertensive effects of α-methyldopa and Nifedipine, maternal hemodynamics and cardiac compliance did not improve pre- and postnatally (p>0.05 for all). Pre- and postnatal assessment showed no significant improvement of CV parameters in women with PE treated with α-methyldopa. These findings are supported by the pre-eclamptic rat model, indicating that current standard therapy for PE does not seem to be sufficient to improve CV impairment.