Aortopathies and Risk Stratification
Women with pre-existing dilatation of the aorta, or disorders that make
them more susceptible to dilatation, should be monitored throughout
pregnancy as they have an increased relative risk for aortic
complications3. It should be noted that many
aortopathies are often only diagnosed following maternal death or
cardiovascular event; in the Genetically Triggered Thoracic Aortic
Aneurysms and Cardiovascular Conditions (GenTAC) study, 42% were aware
of their MFS prior to their first pregnancy5,21. The
aorta is counted as dilated once the diameter exceeds the upper limit of
normal; 2 standard deviations greater than the mean predicted diameter
matched for age and size22.
Women with known aortopathies should have a personalised plan for care
during their pregnancy, including initial pre-conception counselling on
their risk23. Heritable Thoracic Aortic Disease
(HTAD), Loeys-Dietz syndrome, Vascular Ehlers-Danlos (vEDS), MFS,
bicuspid aortic valve (BAV) and Turner syndrome (TS) are all known risk
factors for developing AAD23. An entire imaging of the
aorta should be concluded prior to pregnancy by CT or MRI, as well as
exercise testing, ECG and echocardiography to assess
risk5. Any aortic pathology in these risk groups
warrant ongoing screening; for high-risk— those likely to suffer from
AD or with already dilated aortas— echocardiography every 4 weeks is
necessary, but for low-risk, every 12 weeks.
Counselling on vaginal or Caesarean delivery has been discussed
depending on aortic diameter; vaginal delivery is deemed safe if the
ascending aorta is less than 40mm, but Caesarean delivery should be
considered in all those with ascending aorta >40mm but
particularly in those >45mm or a prior history of
AD5.