Bypass surgery addition to medical therapy fails to impact stroke outcome or death risk in Patients With Symptomatic Artery Occlusion

Previous attempts at EC-IC bypass surgery were unsuccessful in preventing stroke in patients with atherosclerotic occlusion in the internal carotid artery or middle cerebral artery. However, advancements in surgical methods and patient selection have since been made.

The main question is, among symptomatic patients with atherosclerotic occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA), does extracranial-intracranial bypass surgery plus medical therapy reduce stroke or death vs. medical therapy alone?

This was studied at 13 centres in China among the study population of 257 men and 67 women; these adults of mean age 52 years had ICA or MCA occlusion with a transient ischemic attack or non-disabling ischemic stroke.

In the intervention, 330 patients were randomized, and 324 were analyzed. One hundred sixty-one were in the surgical group, including extracranial-intracranial bypass surgery and medical therapy. One hundred sixty-three were included in the medical group, including antiplatelet therapy and stroke risk factor control.

The primary outcome included a composite of stroke or death within 30 days or ipsilateral ischemic stroke beyond 30 days through 2 years after randomization.

The composite primary outcome achieved in the surgical group and the medical group was 8.6 % and 12.3 %, respectively in 13 patients and 19 patients with an incident difference of -3.6 % with a hazard ratio of 0.71

They said the findings do not support the addition of EC-IC bypass surgery to medical therapy for treating symptomatic atherosclerotic occlusion of the ICA or MCA.

Further reading:

Ma Y, Wang T, Wang H, et al. Extracranial-Intracranial Bypass and Risk of Stroke and Death in Patients With Symptomatic Artery Occlusion: The CMOSS Randomized Clinical Trial. JAMA. 2023;330(8):704–714. doi:10.1001/jama.2023.13390