[Morphology of the vascular placental bed in chronic arterial hypertension]

To analyze histopathological patterns of placental bed arteries in pregnancies complicated by chronic arterial hypertension. Alterations were considered according to clinical classification of the hypertensive disorders as mild (MG); moderate (MoG) and severe (SG) for comparison with uncomplicated pregnancies, control group (CG).

Placental bed biopsy was performed in 60 pregnant women; the study group was comprised of pregnant women with hypertension, subdivided in 13 with severe chronic hypertension (CH), 11 with moderate CH and 11 with mild CH, and results were compared to 25 placental bed biopsies from uncomplicated pregnancies. All the pregnant women had a gestational age of at least 28 weeks of gestation with a live fetus and were submitted to cesarean section. Hypertension was considered mild with diastolic blood pressure (DBP) 90 I? 100 mmHg, moderate DBP 100 I? 110 mmHg and severe DBP=110 mmHg. Placental bed variables selected for histological analysis were: unaltered patterns, physiological changes, medial layer disorganization, medial and intimal hyperplasic changes, acute necrosis and atherosis.

In cases with SG and MoG there was predominance of abnormal histophysiological findings: medial layer disorganization and hyperplasic changes, with a statistically significant difference when compared to MG and CG. Alteration in the medial layer was observed in these cases. The normal pattern, unaltered patterns and physiologic changes were more frequent in CG and MG. Physiological changes were the most usual finding, further, there was no acute necrosis or atherosis.

1. Abnormal histophysiological findings were predominant in hypertensive pregnant women compared to the normotensive ones; 2. These patterns were more frequent, according to the severity of the hypertensive disorders: Severe, Moderate and Mild; 3. More significant abnormal findings were a change in the medial layer, mainly in the group with severe hypertensive disorders; 4. The groups with moderate and severe hypertensive disorders when compared had similar results; 5. The normal histological pattern was higher in the control group and patients with mild hypertensive disorders and disclosed a similarity between them 6. The most usual pattern was physiologic changes, which was more frequent in the control group.