Our Strategy for the Endovascular Revascularization of Acute Tandem Internal Carotid Artery and Middle Cerebral Artery Occlusions by Carotid Stenting and Stent Retriever-Assisted Embolectomy: The Anterograde Approach

Approximately 15% of patients undergoing endovascular thrombectomy for anterior circulation acute ischemic stroke have tandem lesions, defined as severe stenosis or occlusion of the cervical internal carotid artery (ICA) ipsilateral to an intracranial occlusion of the ICA or middle cerebral artery (MCA). In comparison to those with solitary intracranial occlusions, patients with tandem occlusions often have a worse outcome, with a mortality rate ranging between 24% and 27% and a good clinical outcome, measured by a modified Rankin Score (mRS) of 0–2, in only 10–29% of cases. Intravenous thrombolysis in these patients has not produced a significant difference in recanalization rates or clinical outcomes compared to placebo. More recently, despite historically poor clinical outcomes, systematic reviews have suggested that these patients may fare better with endovascular management. Both the antegrade approach with proximal-to-distal revascularization and the retrograde method with distal-to-proximal revascularization have been scrutinized. The significant differences and technical considerations for these approaches are the focus of this case discussion. A 67-year-old man with a history of arterial hypertension and dyslipidemia under medical control who had suffered a myocardial infarction 6 years earlier and undergone repeated coronary angioplasties was brought to the emergency room after a witnessed collapse followed by tonic-clonic seizures at his office. At admission, he had tachypnea, and his blood pressure was 184/96 mmHg on the right arm compared with 134/76 on the left arm. On neurological examination, he had left-sided gaze and head deviation, his pupils were equal and reactive, and he had complete mixed aphasia and right faciobrachial and crural hemiplegia, with a National Institutes of Health Stroke Score (NIHSS) of 16. Cranial CT was normal (Alberta Stroke Program Early CT Score [ASPECTS] of 10). However, CT arteriography showed tandem occlusions of the left proximal cervical ICA and the left proximal MCA. Because of his seizures, which were of unclear etiology, CT was complemented by an abbreviated MRI study. Diffusion-perfusion MRI evaluation revealed subtle watershed infarcts and a large perfusion deficit (i.e., a large penumbra). The patient was brought to the angiography suite for urgent revascularization. Under general anesthesia, stent-assisted ICA angioplasty was followed by intracranial stent retriever-assisted thrombectomy with excellent angiographic results. The patient had an uncomplicated subsequent hospital course with a remarkably rapid and complete reversal of his neurological symptoms. This chapter describes technical steps and considerations for the antegrade revascularization strategy in the management of tandem occlusions. This is the preferred and most commonly used approach in our center. We describe our standard step-by-step procedure with its rationale and limitations and review controversies and ongoing debates regarding the antegrade and retrograde approaches.