Prognosis of patients with late spontaneous recanalization of the atherosclerotic occlusion of internal carotid arteries: A pilot case series

Delayed revascularization in acute ischemic stroke patients

Stroke shares a significant burden of global mortality and disability. A significant decline in the quality of life is attributed to the so-called post-stroke cognitive impairment including mild to severe cognitive alterations, dementia, and functional disability. Currently, only two clinical interventions including pharmacological and mechanical thrombolysis are advised for successful revascularization of the occluded vessel. However, their therapeutic effect is limited to the acute phase of stroke onset only. This often results in the exclusion of a significant number of patients who are unable to reach within the therapeutic window. Advances in neuroimaging technologies have allowed better assessment of salvageable penumbra and occluded vessel status. Improvement in diagnostic tools and the advent of intravascular interventional devices such as stent retrievers have expanded the potential revascularization window. Clinical studies have demonstrated positive outcomes of delayed revascularization beyond the recommended therapeutic window. This review will discuss the current understanding of ischemic stroke, the latest revascularization doctrine, and evidence from clinical studies regarding effective delayed revascularization in ischemic stroke.

Delayed Recanalization-How Late Is Not Too Late?

Stroke has become the second most prevalent cause of mortality in the world. Currently, the treatment of ischemic stroke is based on thrombolytic and thrombectomy therapy shortly after the ischemic event (≤ 4.5 h for thrombolytic strategies; ≤ 6 h for thrombectomy strategies). However, the majority of patients are unable to receive prompt treatment, particularly in undeveloped countries. Alternative solutions are lacking for those patients that miss the optimal window of opportunity for treatment. Recently, new developments in imaging techniques and intravascular interventional devices enable the expansion of the window of opportunity for treating stroke patients. Clinical studies have reported that delayed recanalization at 24 h, or even more than 1 month, was beneficial for some patients. However, the mechanisms of neuroprotection that underly the delayed recanalization in these ischemic stroke patients remain unclear. In this review, we will summarize the clinical studies of delayed recanalization, and organize them according to the duration of occlusion. Additionally, we will discuss the changing guidelines and possible mechanisms based on animal research, and attempt to draw conclusions and future perspectives.

Functional outcome after symtomatic internal carotid artery occlusion

Abstract Internal carotid artery occlusion accounts for 15-20% of ischemic strokes, caused by atherosclerosis or dissection. Clinical symptoms are variable, from asymptomatic cases to minor or severe strokes. Diagnosis in internal carotid artery (ICA) occlusion is based on imaging techniques. Prognosis after ICA occlusion depends on many factors: severity of neurologic deficit, spontaneous recanalization of the artery, and the occurrence of recurrent strokes. Patients with spontaneous recanalization of the occluded ICA tend to have a retained functional ability and favorable clinical outcomes. Medical treatment, recanalization techniques and intensive rehabilitation program are essential in improving functional outcome of patients with stroke produced by ICA occlusion. We present the case of a young patient diagnosed with ischemic stroke produced by internal carotid artery occlusion, with consecutive severe neurologic deficit, and an unfavorable functional outcome, as evaluated with the Modified Rankin Scale. Spontaneous recanalization of the occluded ICA was observed after 6 weeks, suggesting a carotid dissection. The patient was included in an intensive rehabilitation program, associated with best medical therapy, showing improvement of its functional status at 3 months follow up. Key words: ischemic stroke, carotid artery occlusion, carotid dissection, spontaneous recanalization, functional outcome,