Hypertensive disorders in pregnancy

Background: Hypertensive complications contribute to maternal and fetal mor bidity. Hypertensive diseases in pregnancy comprise various disorder from t ransient hypertension to the dangerous preeclampsia/eclampsia. Diagnosis of these diseases requires an understanding of the normal physiological adapt ations during pregnancy. Pathogenesis: The primary cause of preeclampsia/eclampsia is a disturbed gr owth of throphoblast cells, probably induced by an altered maternal immunot olerance. The consequent is a dysfunction of endothelial cells with a dt cr t st in perfusion of the uterus and placenta. The normal balance between va soconstrictors and vasodilators is changed ill favor of vasoconstrictors. C omplex changes in the renin-angiotensin system have been detected resulting in an increased angiotensin II-mediated vasoconstriction. The reduction in perfusion of the uterus and placenta eventually leads to preeclampsia/ecla mpsia and growth retardation of the. fetus. Manifest preeclampsia/eclampsia is characterized by disturbed microcirculation of target organs such as br ain, liver and kidney. An involvement of the liver causes the HELLP syndrom e. Therapy: Various pharmacological approaches to prevent preeclampsia/eclamps ia show ed disappointing results, but patients with a risk for the eventual development of preeclampsia/eclampsia should be identified, closely monito red, and hypertension should be treated. A systolic blood pressure > 170 mm Hg and diastolic blood pressure > 100 mm Hg should be treated. Drugs such as alpha -methyldopa and dihydralazine that are well-characterized in their fetal effects are the primary choice for the treatment of hypertension in pregnancy. ACE-inhibitors and angiotensin II receptor antagonists are absol utely, diuretics are relatively contraindicated. The causal therapy for pre eclampsia/eclampsia is delivery. Gravida before the 33th week of pregnancy should be admitted, hypertension should be treated, and the fetus should be monitored by duplex ultrasound and cardiotocography. New data suggest that early treatment with glucocorticoids may prevent the manifestation of HELL P syndrome. Hypertensive pregnant patients should be treated in tertiary ce nters with an interdisciplinary approach involving obstetricians, neonatolo gists, and nephrologists.