Structural and functional changes in left ventricle during normotensive and preeclamptic pregnancy

Abstract

.-Increased cardiac output in pregnancy is associated with cardiac remodeling and possible reduction in contractility, which may worsen in preeclampsia. Left ventricular (LV) geometry and function were compared between nonpregnant controls (n ϭ 12) and normotensive (n ϭ 44) and preeclamptic (n ϭ 15) pregnant women using echocardiography. Loadindependent comparisons of LV systolic function compared end-systolic stress (ESS) and rate-corrected velocity of circumferential fiber shortening (V CFC). Mean arterial pressures were 101 Ϯ 14 mmHg in preeclampsia, 76 Ϯ 6 mmHg in normotensive pregnancy, and 78 Ϯ 6 mmHg in controls (P Ͻ 0.005 vs. preeclampsia). LV mass increased during normotensive pregnancy (66 Ϯ 13 to 76 Ϯ 16 g/m 2 ; P Ͻ 0.05; controls, 65 Ϯ 10 g/m 2 ; P Ͻ 0.05) and was greater in preeclampsia (90 Ϯ 18 g/m 2 ; P Ͻ 0.05). In normotensive pregnancy, ESS decreased (59 Ϯ 9 to 52 Ϯ 11 g/cm 2 ; P Ͻ 0.05; controls, 66 Ϯ 14 g/cm 2 ; P Ͻ 0.005). ESS was greater in preeclampsia (60 Ϯ 14 g/cm 2 ; P Ͻ 0.05). In controls, there was an inverse relationship between ESS and V CFC (r ϭ Ϫ0.78). The ESS-V CFC relationships in normotensive and preeclamptic pregnancy were unchanged from controls. We conclude that LV hypertrophy in normotensive and preeclamptic pregnancy matches changes in cardiac work, and LV contractility is preserved. preeclampsia; echocardiography; ventricular function; myocardial contractility; hypertension PREGNANCY IS ASSOCIATED WITH hemodynamic and hormonal changes that can affect the heart. From the first trimester, there is an increase in cardiac output that places a volume load on the heart. Hormonal changes include increased circulating estrogen and relaxin, which may directly or indirectly affect the heart. During pregnancy, the heart undergoes remodeling similar to that observed in athletes (9, 13) with increases in chamber dimensions, left ventricular (LV) wall thickness, and mass (2, 13, 24) that is consistent with a process of eccentric hypertrophy (15).More controversial is whether myocardial contractile function also changes in pregnancy. Ejection-phase indices of LV function, including systolic fractional shortening (FS) and mean velocity of circumferential fiber thickening (V CFC ), have been variously reported to increase (26), remain constant (15), or decrease (24) during pregnancy. The use of these indices is limited by the changes in ventricular loading conditions that occur during pregnancy. The inverse relationship between ventricular end-systolic stress (ESS) and V CFC has been described as a load-independent measure of contractility (5). The results of one study (21) that used the ESS-V CFC relationship suggest that myocardial contractility is actually reduced during pregnancy. There are even less data about changes in LV diastolic function during pregnancy. Hypertrophy of the left ventricle may result in reduced diastolic compliance (20), whereas hormonal influences such as nitric oxide may have the opposite effect (22).A change in myocardial contractility during pregnancy has impo...

Cardiovascular and electrocardiographic changes in Nigerians with a normal pregnancy

“…Reversal of chamber and hypertrophic changes of normal pregnancy has been shown to occur from a variable period of eight weeks to more than one year post delivery, due to the reversal of the haemodynamic changes associated with pregnancy 14-18. However, the proportion of subjects who reported back was too small to draw a meaningful conclusion on this and further studies are therefore suggested.…”

“…This was in support of previous studies, which had demonstrated that the heart is enlarged by both chamber dilatation and hypertrophy as a result of the haemodynamic changes that occur in pregnancy 5. Acute physiological LVH can occur rapidly during a normal human pregnancy, as an adaptive response to increased preload and cardiac work 14. This can be demonstrated during the second trimester and is most marked at the end of pregnancy 15.…”

Total Vascular Resistance and Left Ventricular Morphology as Screening Tools for Complications in Pregnancy

“…Simmons et al 36 reported that women with preeclampsia tend to decrease their TVR, whereas normotensive women show an increase from antenatal to postpartum. Our report is consistent with those previous findings.…”

Maternal cardiac and obstetric performance in consecutive pregnancies in women with heart disease

“…This is likely due to placental hormone production, with the degree of fall in TPVR directly associated with an increase in cardiac output (CO). 1 Progressive physiological left ventricular hypertrophy also occurs 2 With increasing parity, some of these changes become amplified. Turan et al 3 in a cross-sectional study of maternal cardiac function during pregnancy demonstrated an increased CO in parous as compared with nulliparous women and the difference increased with increasing parity.…”