Management of Myosin Heavy Chain 11–Associated Familial Thoracic Aortic Aneurysm and Dissection During Pregnancy in Two Siblings

Two pregnant siblings presented with thoracic aortic dissection during the second trimester. A pathogenic <i>MYH11</i> was identified following the first sibling's diagnosis. The second sibling, previously known to be at risk but lost to follow-up, reengaged during pregnancy, tested positive for the familial variant, and dissected before her initial evaluation. This case highlights the importance of genetic diagnosis, surveillance, and multidisciplinary care in managing heritable thoracic aortic disease during pregnancy.