Altered maternal left ventricular contractility and function during normal pregnancy

Authors:
Publisher website
Google Scholar
Abstract
Objectives To evaluate maternal left ventricular (LV) systolic and diastolic function during normal pregnancy by non‐invasive measures of LV contractility incorporating loading conditions. METHODS Sixty‐five women were examined using echocardiography, including tissue Doppler and two‐dimensional speckle tracking, and subclavian artery pulse trace recordings at gestational weeks 14–16, 22–24 and 36, and at 6 months postpartum. Results The mean ± SD age of the women was 32.0 ± 4.6 years. Cardiac output and LV end‐diastolic volume were on average 20% and 23% higher, respectively, during pregnancy, compared to that at 6 months postpartum (both, P < 0.01). LV ejection fraction, global peak systolic strain and rate‐corrected LV velocity of circumferential fiber shortening (Vcfc) were 11%, 6% and 6% lower, respectively, at 36 weeks' gestation compared to at 6 months postpartum (all, P < 0.01). Afterload, measured as LV end‐systolic wall stress (ESWS) increased by 10% between 14–16 and 36 weeks' gestation (P < 0.01). Analysis of the relationship between Vcfc and ESWS revealed that LV contractility was lower during pregnancy than at 6 months postpartum. Changes in diastolic function were demonstrated by 11% lower mitral early diastolic (E) wave velocity, 8% lower tissue Doppler early diastolic velocity (e′) and 13% higher left atrial area (all P < 0.01) during pregnancy. Tissue Doppler E/e′ remained unaltered (P = 0.78). Conclusions During normal pregnancy, LV contractility is lower than it is at 6 months postpartum. This is associated with increased LV and left atrial area, whereas filling pressures are unchanged. These findings suggest that pregnancy exerts a larger load on the cardiovascular system than previously assumed. Copyright © 2012 ISUOG. Published by John Wiley & Sons Ltd.

This publication has 36 references indexed in Scilit: