Genetics, Pregnancy, and Aortic Degeneration

We present a case of familial thoracic aortic aneurysm and dissection (FTAAD) in a pregnant female. FTAAD is an inherited, nonsyndromic aortopathy resulting from several genetic mutations critical to aortic wall integrity have been identified. One such mutation is the myosin heavy chain gene (MYH11) which is responsible for 1-2% of all FTAAD cases. This mutation results in aortic medial degeneration, loss of elastin, and reticulin fiber fragmentation predisposing to TAAD. Aortic disease is more aggressive during pregnancy as a result of increased wall stress from hyperdynamic cardiovascular changes and estrogen-induced aortic media degeneration. Our patient was a 29-year-old G2P1 woman at 26 weeks gestation presenting with abdominal and back pain. Work-up revealed a 6.4-cm ascending aortic aneurysm with a type A dissection extending into all arch vessels, aortic coarctation at the isthmus, and a separate focal type B aortic dissection with visceral involvement. Surgical management included concomitant cesarean section with delivery of a live premature infant, tubal ligation, ascending aortic replacement with reconstruction of the arch vessels, and aortic valve resuspension. The type B dissection was managed medically without complication. This is the first reported case of aortic dissection in a patient with FTAAD/MYH11 mutation and pregnancy. This case highlights that FTAAD and pregnancy cause aortic degeneration via distinct mechanisms and that hyperdynamics of pregnancy increase aortic wall stress. Management of pregnancy associated with aortopathy requires early transfer to a tertiary center, careful investigation to identify familial aortopathy, fetal monitoring, and a multidisciplinary team approach.