Objective: To investigate serum cardiac troponin I, a sensitive marker of cardiac myocyte damage, in normal pregnancy and pregnancies complicated by hypertension with and without significant proteinuria.
Design: Prospective cross sectional study.
Setting: University hospital delivery suite.
Sample: Serum samples obtained from women in normal pregnancy and in pregnancies complicated by hypertension with and without significant proteinuria.
Method: Women with hypertension in pregnancy (at least two readings of systolic blood pressure > 140 mmHg and diastolic blood pressure > 90 mmHg) (n = 26) and normotensive women (n = 43) were included in the study. Serum cardiac troponin I was measured using Beckman Access immunoassay.
Main outcome measure: Serum cardiac troponin I level in the pregnancies complicated by hypertension (with and without significant proteinuria) compared with the levels measured in normotensive women.
Results: The median serum cardiac troponin I level in pregnancies complicated by hypertension was 0.118 ng/mL (n = 26) which was significantly greater than that measured in samples obtained from normotensive women in pregnancy (0.03 ng/mL; n = 43) (P < 0.0001). There were higher median serum cardiac troponin I levels in hypertensive women with significant proteinuria (0.155 ng/mL; n = 6), compared with those without proteinuria (0.089 ng/mL; n = 20; P = 0.03).
Conclusion: Serum cardiac troponin I is elevated in women with hypertensive disorders of pregnancy indicating some degree of cardiac myofibrillary damage in these disorders.