DISCUSSION
Classically, AD’s present with widened pulse pressure, unequal blood
pressures in upper extremities, and pathognomonic ‘tearing’ chest pain
radiating to the back.1 However, recent literature has
suggested these easily recognizable findings may not be as common, with
one study finding only 50.6% of dissections to present with pain
described as “tearing or ripping” and just 28.3% with radiating
pain.5 Conversely, some cases present with vague
symptoms, such as diarrhea and vomiting, which may easily be confounded
with general malaises of pregnancy, as was the case with our patient
initially.6 Individualizing risk factors in ambiguous
settings such as these may make diagnoses more definitive. Our patient
not only had chronic hypertension - a common risk factor for AD - but
was also pregnant, which increased the likelihood of dissection from
1.24 per million in non-pregnant women to 14.5 per million in pregnant
women due to the hyperdynamic state and hormonal effects on vasculature
associated with pregnancy.4,7
One of the challenges in diagnosing AD during pregnancy is imaging.
While the gold standard for AD diagnosis has traditionally been CTA,
both radiographs and CT scans are discouraged in pregnancy due to the
potentially harmful effects of radiation to the
fetus.8 In addition, contrast dyes utilized for
angiography have been well-associated with nephropathy, potentially
exacerbating the already-comprised state of the kidneys due to
physiological changes of pregnancy.9,10 Although the
dose of radiation delivered by CTA is below the limit for fetal harm,
thus leaving the American College of Obstetrics and Gynecology in favor
of utilizing CT imaging in pregnant patients that require
imaging.11 Other imaging alternatives, such as
magnetic resonance imaging, can be utilized in pregnant patients with
varying diagnostic accuracy and availability.8
Surgical planning for AD in pregnant patients is challenging,
necessitating effective communication between the patient,
anesthesiologists, obstetricians, and cardiac surgeons. Factors that
impact clinical decision making include the onset and presentation of AD
symptoms, hemodynamic stability, and fetal
viability.12 Additionally, surgical repair is
generally poorly tolerated with fetal loss upwards of 30% due to a
complex response to stress and cardiopulmonary
bypass.13 Although there are no official guidelines
regarding the management of AD in pregnancy, some have proposed
tailoring treatment based on gestational age.4Additional literature has developed this strategy further by suggesting
emergent cesarean section with sternotomy standby followed by surgical
repair of the aorta within a few days.14 In our
patient’s case, the clinical team decided to have the patient undergo
cesarean section first, in case of any hemodynamic instability that may
have developed during the procedure.
We present a case of successful surgical treatment of an AD in a
pregnant patient after an initial delay in diagnosis treated with a
staged approach of delivery followed by delayed dissection repair. AD’s
represent a potentially catastrophic complication of pregnancy. Although
AD’s are thought to have the hallmark easily identifiable tearing chest
pain, atypical presentations may delay accurate diagnosis and clinical
management. Increased clinical suspicion for AD is warranted in patients
with corresponding risk factors, especially pregnancy. Treatment aims to
mitigate the risk of both fetal and maternal demise, and typically
includes emergent cesarean section and AD defect repair, though
consensus regarding the timing of repair is currently lacking. While AD
in the general population is well studied, future studies should aim to
better describe how AD may present during pregnancy and how management
differs in the gravid patient from that of non-pregnant patients.