Fatal Outcome Due to Pulmonary Arterial Intramural Hematoma Associated With Stanford Type A Acute Aortic Dissection: A Case Report.

Stanford type A acute aortic dissection (AAD) is associated with a poor prognosis. Pulmonary artery intramural hematoma (PA-IMH) is an underrecognized complication of AAD. Here, we report a case of an 86-year-old man diagnosed with Stanford type A AAD. During emergency transfer to a tertiary care center with cardiovascular surgical capabilities, the patient experienced a cardiac arrest during transport by an ambulance and was subsequently pronounced dead. Postmortem computed tomography (CT) revealed right PA compression and wall thickening consistent with PA-IMH. Additionally, associated ground-glass opacity in the right lower lobe suggested alveolar hemorrhage, likely contributing to circulatory collapse, followed by cardiac arrest and death. We identified two important clinical issues. First, in cases of AAD, PA-IMH should be considered a potential complication when contrast-enhanced CT reveals obstruction or stenosis of the PA. Second, some cases of PA-IMH may present with alveolar hemorrhage, an important prognostic factor of PA-IMH that should be identified using CT with lung window settings.