Right ventricular function and pregnancy in congenital heart disease

We aimed to improve risk stratification in pregnant women with congenital heart disease (CHD) based on increasing our knowledge about the possible underlying pathophysiological mechanisms between the heart and placenta and to clinical factors related to increased risk of pregnancy complications. We showed in both heterogeneous and homogenous populations of pregnant women with CHD that reduced maternal right ventricular (RV) function before and during pregnancy is associated with impaired uteroplacental circulation, which is in turn, associated with adverse pregnancy outcome. Evidence is increasing that reduced RV function is a predisposing factor for impaired placental function, possibly due to venous congestion. The relation between cardiac dysfunction and placenta development and function is not yet established well, but it is most likely multifactorial with synergistic effects. Maternal hypoperfusion, increased central venous pressure, pre-existing hypertension and chronic hypoxia all lead to placental malfunction, and their interaction may amplify the negative impact. Furthermore, we showed that first trimester N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (>235 pg/mL) are associated with adverse cardiovascular complications and a decline in RV function later on during pregnancy in women with CHD. This thesis added valuable new insights to the knowledge of the underlying pathophysiological mechanisms between the heart and placenta in women with CHD. Venous congestion related to (sub)clinical RV dysfunction may play an important role. Early evaluation of RV function, NT-proBNP and uteroplacental circulation is of additional value to identify pregnant women with increased risk of complications and is useful for tailored care in pregnant women with CHD.