Spontaneous cough-induced rupture of a perforating branch of the right internal mammary artery presenting as an abdominal wall hematoma. A case report

Spontaneous rupture of the internal mammary artery is an uncommon and potentially life-threatening event, classically presenting with hemothorax, mediastinal hematoma, or hemopericardium. Presentation as an abdominal wall hematoma is unusual and coughing represents a rare trigger. We report a case of an 84-year-old man with atrial fibrillation receiving anticoagulant therapy who suddenly developed right thoraco-abdominal pain and progressive anemia after a violent coughing episode. Contrast-enhanced CT demonstrated a large right thoraco-abdominal wall hematoma with active contrast medium extravasation. Although initial angiography of the inferior epigastric artery was inconclusive, selective catheterization of the right internal mammary artery demonstrated active bleeding from a perforating branch, identifying an alternative source for abdominal wall hemorrhage. Selective coil embolization achieved immediate hemostasis, and follow-up CT confirmed hematoma reduction without recurrent extravasation. To our knowledge, few cases of an isolated cough-induced spontaneous rupture of an internal mammary artery perforating branch presenting as an abdominal wall hematoma have been reported previously. This case expands the spectrum of spontaneous internal mammary artery injuries, highlighting a rare cough-related mechanism and an atypical extra-thoracic presentation as an abdominal wall hematoma. Recognition of this entity is crucial in elderly or anticoagulated patients presenting with acute thoraco-abdominal pain after forceful coughing, as prompt CT angiography and endovascular treatment can be decisive.