Alterations of systolic time intervals in the assessment of myocardial function during hypertensive pregnancy.

The alterations in the systolic time intervals caused by hypertension during pregnancy have been investigated. A group of 20 women who developed hypertension only during pregnancy (HP), and a group of 16 women who began pregnancy with established hypertension (EHP) were matched with 25 normal pregnant women (N). The study was performed (I) during the third trimester, (2) five days after delivery and (3) five weeks after delivery, both in supine and in lateral postures. In the third trimester the two hypertensive groups, when compared with the normal group, were characterized by a shorter left ventricular ejection time (LVET: 407±3 ms for the normal group v. 390±2ms for the HP group, P<0.001; v. 398±2ms for the EHP group, P<0.02), and a longer pre-ejection period (PEP,: 138±2 ms for the normal group v. 154 ± 2 ms for the HP group P<0.001; v. 145± 1 ms for the EHP group, P<0.05). When the two hypertensive groups were compared with each other the HP group showed a shortened LVET and a prolonged PEP (P<0.01), and also a slower heart rate (HP 74±3bmin. EHP 83±3 b min P<0.05). Five days after delivery while systolic time intervals of the HP group (LVET = 400±3 ms; PEP= 144±2 ms) were partially returning toward the values of the normal group (LVET=410±2 ms; PEP137±2ms), those of the EHP group showed a further worsening (LVET = 397±3 ms; PEP= 151 ±2 ms). Five weeks later, most of the indices were within normal limits. It is concluded that when hypertension is superimposed on pregnancy, it causes significant changes in cardiac performance; the women who develop hypertension only during pregnancy show the greatest changes. After delivery, systolic time intervals gradually return toward normality. [ABSTRACT FROM PUBLISHER]