Introduction
Hypertensive disorders of pregnancy (HDP) are associated with 2-3 fold increased risk of future cardiovascular disease. Cardiac remodeling and abnormal systolic and diastolic function have been reported during an HDP pregnancy. Whether these changes persist post-partum is uncertain. We assessed cardiac structure and function 6 months post-partum in women with prior HDP.
Methods
A sub-group of the prospective P4 study (Postpartum, Physiology, Psychology and Paediatric study) cohort were recruited 6 months post-partum for transthoracic echocardiography (TTE) and 24 hour BP measurement (ABPM) between February 2014 and July 2017. Women had either prior HDP or NP (pre-existing HT was excluded). Transthoracic echocardiography was performed by a blinded echocardiographer.
Results
There were 39 women with prior HDP (33 preeclampsia, 6 gestational hypertension) and 40 NP. The HDP group was younger (31±5 v 33±4yrs, HDP v NP, p= 0.04). There were structural and functional differences on echocardiography. Structural differences included thicker interventricular septum (8.8 v 8.1mm, HDP v NP, p=0.007), thicker posterior wall (8.6 v 7.7mm, HDP v NP, p<0.001), greater relative wall thickness (0.37 v 0.35, HDP v NP, p=0.02) and higher left ventricular (LV) mass (109 v 94g, HDP v NP, p=0.02). The HDP group also had impaired LV relaxation as indicated by a higher E/E’ ratio septal (8.78 v 7.5, HDP v NP, p=0.007). Systolic function between groups was similar as measured by global longitudinal strain and LV ejection fraction. LV mass correlated with 24hr SBP (r=0.24, p<0.05) and BMI (r=0.43, p<0.001). Diastolic function correlated with BMI (E/E’ ratio, r=0.52, P<0.001) but not 24hr SBP.
Conclusions
At six months post-partum, there were subtle yet significant changes in cardiac structure and diastolic function in women with prior HDP. Our data suggest both haemodynamic and metabolic factors may contribute to these findings.