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The aim of this study is to evaluate the hemodynamics and pregnancy outcome of women with prior orthotopic liver transplantation. Hemodynamic measurements by Doppler technique were performed on pregnant subjects with prior orthotopic liver transplantation. Maternal characteristics, renal function, pregnancy complications, delivery indications, delivery mode, and neonatal outcomes were evaluated. Six pregnancies occurred in 5 women after orthotopic liver transplantation at the University of Washington Medical Center (Seattle, WA) between 1991 and 1999. Four of the 6 pregnancies were complicated by chronic hypertension, fetal growth restriction, and preterm delivery. Two pregnancies had worsening hypertension characterized by vasoconstriction in the second trimester despite antihypertensive therapy. These 2 subjects were administered cyclosporine for maintenance immunosuppression and had greater mean arterial pressures preconception and in the first trimester than the other subjects. One of these pregnancies resulted in fetal demise at 25 weeks' gestation. The other subject was delivered at 28 weeks' gestation for nonreassuring fetal status and superimposed preeclampsia. All pregnancies were complicated by renal insufficiency; however, the 2 subjects with poor obstetric outcome had preconception serum creatinine levels greater than 1.5 mg/dL and creatinine clearances less than 40 mL/min. Pregnancies complicated by second-trimester vasoconstriction and moderate renal insufficiency are at risk for preeclamspia, fetal growth restriction, and fetal demise. Good obstetric outcome can occur in women with mild renal insufficiency and well-controlled chronic hypertension. Improved hypertensive control preconception may decrease the risk for preeclampsia and poor obstetric outcome.

Objective: To describe the clinical course of pregnancies complicated by pulmonary hypertension and treated with the pulmonary vasodilators nifedipine and prostacyclin., Methods: Four pregnant women with pulmonary hypertension were treated with pulmonary vasodilators. Therapy with oral nifedipine and intravenous prostacyclin was guided by right pulmonary artery catheterization and Doppler measurements of cardiac output., Results: Three of four women responded to vasodilator therapy and successfully completed their pregnancies. Two who conceived at least 1 year after successful treatment and normalized right ventricle function carried three uncomplicated pregnancies. The woman who did not respond died. Delay in diagnosis contributed to her outcome. Noninvasive measurement of cardiac output helped diagnosis of right ventricular failure and offered reassurance in women who remained compensated. Postpartum decompensation in one woman was characterized by a negative Starling response as central venous pressure increased from 4 to 11 mmHg. She responded positively to diuresis., Conclusion: Early diagnosis of pulmonary hypertension is critical. Volume overload postpartum might significantly contribute to decompensation. We recommend a year of successful therapy after a response to vasodilator therapy and near-normal right ventricular function before pregnancy is considered. In complicated pregnancies, women must balance the best estimate of risk with the value they put on pregnancy.

Objective: To determine the effect of third-trimester calcium supplementation on maternal hemodynamic function., Methods: Pregnant women were randomized to receive either 1.5 g of elemental calcium or placebo for 6 weeks during the third trimester. Using Doppler technique, maternal hemodynamic characteristics were measured at baseline, at 2 hours after the first dose of study drug, and at the completion of 6 weeks. Serum, dietary, and urinary calcium levels were also assessed. Power calculation indicated the need to study ten subjects in each group to detect a 1.2 L (20%) difference in cardiac output between groups, assuming a mean of 6.2 +/- 1.0 L/minute. Data were analyzed by analysis of variance for repeated measures, Student t test, Mann-Whitney U test, and Fisher exact test., Results: Twenty-three women enrolled, and 18 completed the study. There were no statistically significant differences in demographic characteristics or in serum, dietary, or urinary calcium levels between the two groups. There were also no statistically significant differences in hemodynamic function over time within the calcium supplementation or placebo group (P > .05; analysis of variance for repeated measures). After 6 weeks, there were no significant differences between the calcium- and placebo-treated subjects in any hemodynamic measurement. Specifically, there was not a statistically significant difference in cardiac output (7.3 +/- 1.2 L/minute versus 8.0 +/- 0.9 L/minute; P = .09) between the calcium- and placebo-treated groups., Conclusion: These findings suggest that third-trimester calcium supplementation does not significantly alter cardiac output. The mechanism by which calcium supplementation lowers blood pressure remains to be elucidated.

The aortic diameters of 89 normotensive pregnant women were compared with those of nine rigorously defined preeclamptic women and 59 women who required antihypertensive therapy. Over the course of normal pregnancy, the diameter increased significantly; it was larger in preeclamptic than in normotensive women throughout pregnancy. The aortic diameter in women with high-resistance hypertension was smaller than that in normotensive women and in those with high-output, low-resistance hypertension, but it was larger in women with low-resistance hypertension than in normotensive women. The aortic diameter increased after treatment of high-resistance hypertension with hydralazine, but decreased after treatment of high-output, low-resistance hypertension.

The hemodynamics of six pregnant women with hyperthyroidism were studied before and after therapy. Cardiac output was measured by Doppler technique, and blood pressure by automated cuff. When compared with values in euthyroid pregnant women, blood pressure (83.6 mmHg, P less than .001), heart rate (89.2 beats per minute, P less than .001), cardiac output (11.2 L/minute, P less than .001), and stroke volume (123 mL, P less than .001) were significantly elevated. Total peripheral resistance was significantly reduced (609 dyne.second.cm-5, P less than .001). Despite normalization of thyroid indices after therapy, cardiac output remained markedly elevated (9.7 L/minute, P less than .001) and vascular resistance remained reduced (708 dyne.second.cm-5, P = .01). Although the hemodynamics of pregnant thyrotoxic women normalize with therapy, they remain significantly hyperdynamic.

Preeclampsia is a disease unique to pregnancy that contributes substantially to maternal and fetal morbidity and mortality. The condition has been thought to be one of hypoperfusion in which increased vascular resistance characterizes the associated hypertension. This study was designed to test an alternative hypothesis, that preeclampsia is characterized by high cardiac output. In a blinded longitudinal study of nulliparas with uncomplicated pregnancies, cardiac output was measured serially by Doppler technique. Cardiac output was elevated throughout pregnancy in patients who became preeclamptic (P = .006). Six weeks postpartum, the hypertension of the preeclamptic subjects had resolved but cardiac output remained elevated (P = .001) and peripheral resistance remained lower than in the normotensive subjects (P = .001). This study demonstrates that preeclampsia is not a disease of systemic hypoperfusion and challenges most current models of the disease based on that assumption.

Doppler technique of measuring cardiac output was evaluated during pregnancy. In a study of accuracy Doppler technique correlated well with thermodilution, (r = 0.95, y = 1.05x - 0.35). In a study of interoperator variability, the technique was found to be reproducible, (r = 0.92, y = 0.91x + 0.74).

In 12 patients requiring pulmonary artery catheterization, cardiac output was measured using Doppler and thermodilution techniques. The Doppler technique accurately predicted measurements made by thermodilution (r = 0.91; P less than .001). Eighteen normal patients in the third trimester and 36 preeclamptics who had not been treated with medications other than magnesium sulfate were evaluated with Doppler alone. Of note was the heterogeneity among preeclamptics. Although their mean systemic vascular resistance was elevated, it ranged from 2256-648 dyne X sec X cm-5. Cardiac output ranged from 13.2-3.9 L/minute.

A patient with pheochromocytoma diagnosed at 17 weeks' gestation was studied at rest, during an episode of paroxysmal hypertension, and during phenoxybenzamine treatment. Cardiac output was estimated noninvasively by Doppler technique. During paroxysmal hypertension, the mean blood pressure was 102 mmHg, cardiac output fell by 40%, and systemic vascular resistance rose by 250%. Phenoxybenzamine treatment did not change the resting cardiac output or systemic vascular resistance. These observations suggest that serious fetal compromise might occur even with mild episodes of hypertension associated with pheochromocytoma.

The effects of orthostatic stress on cardiac output and systemic vascular resistance have not been previously studied in pregnancy. A Doppler technique of measuring cardiac output was used to study 15 nonpregnant women, 14 pregnant women in the first trimester, and 16 pregnant women in the third trimester. Subjects were studied in recumbent, sitting, and standing positions. In each group, the change from recumbent to standing positions resulted in a fall in cardiac output of 1.7-1.8 L/minute (P = .001). Systemic vascular resistance rose in each group (P = .001). The magnitude of the rise was greatest in nonpregnant women and smallest in the third trimester (P = .005). The observed fall in cardiac output and rise in systemic vascular resistance may be clinically significant in pregnancies complicated by uteroplacental insufficiency.