Investigating TAAD in Pregnant Women
CT aortography, MRI and transoesophageal echocardiography (TOE) have all
proven useful in the diagnosis of TAAD in pregnancy. The historical gold
standard for the diagnosis of TAAD is CT
aortography16. In pregnancy, there is often concern
raised about potential fetal harm linked with radiation exposure. This
fear could potentially lead to delayed or missed diagnosis.
Varying recommendations regarding the optimum investigation strategy for
these women exists across different governing bodies. The American
College of Obstetricians and Gynecologists recommend that ionizing
radiation through the use of radiography, CT or nuclear imaging should
not be withheld from a pregnant woman if it is more readily available or
thought to be necessary in addition to ultrasonography or MRI14. This is
because, with few exceptions, the radiation dose is much lower than the
exposure associated with fetal harm17,18. In a similar
sentiment, the European Society of Cardiology recommend for
haemodynamically unstable patients, the quickest form of imaging should
be utilised, whether MRI, CT or TOE19. If stable, they
recommend the use of MRI. Advantages of TOE as a diagnostic tool also
extend to its versatility, and can be used throughout the hospital, from
intensive care, emergency department and theatres to assess real time
information regarding location and extent of dissection, which is ideal
for patients who are haemodynamically unstable20.
Dissection complications such as pericardial effusion and aortic
insufficiency can be assessed12. The disadvantages of
TOE are of a practical nature; availability across hospital trusts, and
it is an invasive procedure requiring an experienced technician due to
operator-dependent results; sensitivity can vary, reported between 59
and 83%, and specificity 63 – 93%12. With this
knowledge, a high clinical suspicion should not deter from an additional
investigation such as CT or MRI12.