Internal Carotid Artery Bifurcation Aneurysm: Ruptured Internal Carotid Artery Aneurysm in a Patient with Corrected Coarctation of the Aorta Treated with Balloon-Assisted Coiling, Exclusion of the Aneurysm, and Good Clinical Outcome

Saccular aneurysms occur in up to 10% of patients with coarctation of the aorta and are frequently multiple. Aneurysm size tends to increase with age, as does the risk of rupture. Uncontrolled hypertension promotes the growth of these aneurysms and increases the risk of rupture. Following a mechanistic approach, treatment of aortic coarctation aims to control the stenotic segment; however, even after adequate anatomical repair and irrespective of the approach used, up to 30-40% of patients develop systemic arterial hypertension. Adding to this puzzle, the risk of aneurysm rupture remains after the coarctation has been repaired, even if there is no longer any hypertension. In some ways, aortic coarctation could be considered a systemic vascular disease of the precoarctation arteries. A 24-year-old woman experienced an episode of sudden onset severe headaches, vomiting, and loss of consciousness, ending up in a deep coma. She was assisted by paramedics, who rapidly intubated her and transferred her to our hospital emergency room. On admission, the patient was in a coma (Glasgow Coma Score [GCS] 6) with right-hand anisocoria. CT/CTA of the head revealed a diffuse subarachnoid hemorrhage (SAH), left frontobasal and intraventricular hemorrhage with associated hydrocephalus (Fisher grade 4), and a midsized irregularly shaped aneurysm on the bifurcation of the left internal carotid artery (ICA). Emergent external ventricular drainage was put in place to alleviate increased intracranial hypertension and the patient was immediately transferred to the neurointerventional department. During the diagnostic angiography, we discovered a stent implanted in the proximal descending aorta. We crossed over this implanted aortic stent and confirmed the presence of an irregularly shaped midsized saccular aneurysm on the bifurcation of the left ICA. The aneurysm was embolized using a balloon-assisted coiling technique in a procedure that was considered to have been straightforward and unremarkable. The aneurysm was completely excluded, and at the end of the intervention the gradient across the aortic stent was 24 cmH₂O. The patient was transferred to ICU for clinical and neurological monitoring. Her clinical course was complicated by pneumonia and vasospasm. The patient was extubated on postoperative day 12 and was transferred to a rehabilitation facility on day 23. At 60 days, she was able to walk independently and she recovered even further after intense rehabilitation work. Her headache pain was successfully treated with nonsteroidal anti-inflammatory drugs (NSAIDS) and opioid analgesics. This case exemplifies an unusual medical situation: the urgent need for the endovascular embolization of a brain aneurysm in a patient with an aortic stent implanted for the management of aortic coarctation. The association between aortic coarctation and brain aneurysms and the increased risk of aneurysm rupture, even after aortic repair, are the main topics of this chapter.