Middle Cerebral Artery (M3) Aneurysm: Atypical Primary Morphology and Early Recurrence After Stent-Assisted Coil Occlusion During the Long-Term Left Ventricular Assist Device Treatment, Accompanied by Temporary Septicemia; Parent Vessel Occlusion as the Final Treatment with Good Clinical Outcome

Abstract

A 58-year-old male patient presented with a subarachnoid hemorrhage (SAH) due to the rupture of a distal aneurysm of a left middle cerebral artery (MCA, M3) branch. Stent-assisted coil occlusion was performed successfully, preserving the parent artery lumen. The patient was undergoing long-term treatment with a left ventricular assist device (LVAD) for his progressive congestive cardiac failure and had encountered long episodes of impaired wound healing and LVAD-associated infections. During an assessment for a heart transplant, a non-enhanced cranial CT scan was performed, which raised the suspicion of aneurysmal parenchymal hemorrhage. DSA showed further growth and recurrent perfusion in the aneurysm, which had been occluded 21 months earlier. There was no recurrent hemorrhage. Since the parent artery no longer supplied a large volume of brain parenchyma, it was decided to treat it with proximal parent vessel occlusion (PVO) using coils. This was performed successfully and followed by a course of antimicrobial chemotherapy. The patient recovered without neurological deficit. In the presence of sepsis or other systemic infections, an early and morphologically atypical recurrence of a previously treated intracranial aneurysm suggests an underlying bacterial infection. This scenario requires immediate antibiotic therapy and rigorous treatment of the aneurysm. Long-term treatment with cardiac assist devices can create ideal conditions for chronic infection, as a biofilm may form along the intra-corporal parts of the device, which then serve as a focus for septicemia. This carries significant risk of primary aneurysm formation as well as of superinfection of previously occluded aneurysms where the infection infiltrates, inflames, and thus weakens the vessel wall. This latter scenario could cause an initially sufficiently treated aneurysm to rapidly relapse and grow further. For distally located infectious aneurysms, PVO is a viable treatment option. The management of “mycotic” aneurysms is the main topic of this chapter.