Background: Theoretically, recurrent stroke symptoms caused by severe internal carotid artery (ICA) stenosis should resolve on progression of stenosis to complete occlusion. However, stroke symptoms may recur due to the occluded ICA stump (carotid stump syndrome). We investigated the clinical characteristics and treatment outcomes in patients with ICA stump.
Methods: Subjects were recruited from a stroke registry at a university hospital (Feb 2005 to Jan 2015). The eligibility criteria were 1) extracranial ICA occlusion on computed tomographic angiography (CTA) as a stump morphology and 2) acute ischemic stroke or transient ischemic attack in the corresponding arterial territory <7 days from symptom onset. The exclusion criteria were 1) presumed etiology as cardiac embolism or other etiology (e.g., dissection, moyamoya syndrome, and vasculitis) and 2) concomitant carotid T type occlusion on CTA. A total of 114 patients were categorized into the stable (N=90) and unstable (N=24) groups. Unstable group indicated stroke recurrence in <3 months, or progression of ischemic stroke during hospitalization. Progression of stroke was defined as 1) change in NIHSS score ≥2 or 2) change of NIHSS score ≥1 with malignant change or increase of infarct size. Intensive statin treatment was defined as ≥10 mg of rosuvastatin and/or ≥20 mg of atorvastatin. Logistic regression analysis was performed to identify prognostic factors.
Results: There were no significant inter-group differences with respect to age, sex, and mode of thrombolytic therapy. Metabolic syndrome and initial heparinization were both more frequent in the unstable group than in the stable group. (83.3% vs. 46.7%, p=0.001 and 41.7% vs. 10.0%, p<0.001, respectively). Frequency of intensive statin treatment was lower in the unstable group (41.7% vs. 65.6%, p=0.033). On multivariate analyses, metabolic syndrome, initial heparinization, and non-use of intensive statin therapy were independent risk factors for progression or recurrence.
Conclusion: Metabolic syndrome was the main risk factor for progression/recurrence of stroke caused by ICA stump. Intensive statin treatment seems to be beneficial in these patients. The benefits of initial heparinization appear to be questionable.