Perforation of the Frontal Middle Cerebral Artery Branch (Distal M2) During Stent Retriever-Assisted Mechanical Thrombectomy, Controlled by Temporary Balloon Occlusion and “Microcatheter-Based Occlusive Hemostatic Technique”

Intraprocedural perforations during stentriever thrombectomy are rare but are associated with clinical deterioration and high mortality. Perforations most commonly occur in medium-sized vessels and result from arterial damage caused by difficulty traversing a distal occlusion with a microcatheter or microwire, or during maneuvers to withdraw the stentriever. This 86-year-old woman with a history of hypertension, hyperlipidemia, diabetes mellitus type 2, and ischemic heart disease treated with aspirin presented to the emergency room (ER) with motor dysphasia and right hemiparesis. Upon admission, her National Institutes of Health Stroke Scale (NIHSS) score was 10 points. She was last seen well 1 h before admission to the ER. The Alberta Stroke Program Early CT Score (ASPECTS) on noncontrast cranial CT (CT) was 10. CT angiography (CTA) showed complete occlusion of the left middle cerebral artery (MCA) in its proximal sphenoidal segment with no “stump,” raising suspicion of a chronic atherosclerotic lesion and moderate retrograde perfusion of the distal MCA branches through leptomeningeal collaterals. CT perfusion confirmed normal perfusion parameters in the left MCA territory. The patient did not receive intravenous thrombolysis and was directly transferred to the angiography suite for endovascular intervention. The patient underwent stentriever-assisted mechanical thrombectomy, which allowed clearing of the MCA stem and revealed an underlying atherosclerotic plaque that was causing severe stenosis of the proximal MCA trunk. Unfortunately, the third thrombectomy pass was complicated by a perforation of the frontal MCA branch in the distal insular segment. This complication most probably occurred during stentriever deployment with a slight advance of the stentriever distal end during delivery. To control the bleeding, the balloon of the guiding catheter located at the cervical internal carotid artery (ICA) was immediately inflated, anesthesia was deepened, and arterial pressure was reduced. In addition, a double-lumen percutaneous transluminal angioplasty (PTA) balloon catheter was repeatedly inflated at the proximal MCA trunk for 5-minute intervals. In this way, we dilated the stenotic MCA segment and obtained proximal control of the bleeding point. However, this strategy allowed only partial reduction of contrast extravasation. The bleeding artery was considered eloquent in terms of speech and motor functions, and thus we were reluctant to sacrifice it by coiling or glue injection. Instead, to obtain more precise control of the bleeding point, we advanced a 0.017″ microcatheter into the frontal MCA branch. The small caliber of the artery allowed us to place it in an occlusive fashion. The microcatheter was maintained in place for 5 min and then removed. Angiography obtained after its removal confirmed complete revascularization of the MCA stem and its major branches with some delay in antegrade filling of the distal MCA territory (Thrombolysis in Cerebral Infarction [TICI] score 2b), and no active hemorrhage. Immediately after the procedure, the patient was kept deeply sedated. CT showed a thick subarachnoid hemorrhage mixed with contrast, and slight ventricular enlargement. An external ventricular drain was placed for 24 h to monitor and control intracranial pressure and clear the CSF. The patient was extubated 36 h after the procedure. Follow-up head CT showed clearing of the subarachnoid hemorrhage with no hydrocephalus. The patient had a prolonged and complicated hospital stay and was transferred to a rehabilitation facility with NIHSS of 9 and mRS of 3. She was discharged on dual antiplatelet therapy with aspirin and clopidogrel for 3 months and atorvastatin. Management of medium-size vessel perforations complicating mechanical thrombectomy is the main topic of this chapter.