Abstract T MP28: High Rate of Symptomatic Intracranial Stenosis (sICS) in Patients Treated with Systemic Thrombolysis at a United States Stroke Belt Tertiary Care Center
Background & Purpose: sICS is a common mechanism for acute ischemic stroke (AIS), believed to preferentially affect Asians and Blacks compared to Whites. In the U.S., the reported rates of sICS for regions other than the Stroke Belt are 17% among hospitalized Blacks and 9% among Whites with AIS. We aimed to determine the rate of sICS among stroke patients treated at our Southeastern U.S. center.
Subjects & Methods: Consecutive AIS patients receiving IV tPA admitted to our tertiary center were routinely evaluated for the presence of intracranial stenosis (≥50% diameter reduction in the intracranial vessel supplying the affected territory) using either CT-angiography, catheter angiography, contrasted MRA or standardized transcranial Doppler (TCD). All imaging studies were performed following reperfusion therapy within 48 hours from symptom onset. Our published TCD criteria were previously validated against WASID measurements. Persisting arterial occlusions (TIMI 0-1 flow) and patients with cardioembolism as the only suspected stroke mechanism were not considered as having sICS.
Results: We examined 318 patients who received IV tPA at our center in 2010-12 (52% men, mean age 62±16 years, median NIHSS 5, IQR 8, 36% Blacks, 63% Whites, 1% Other) who underwent multi-modal vascular imaging with at least 2 of the 4 abovementioned modalities post treatment. Symptomatic ICS was found in 84 (26%) patients (63% men, 65±17 years, 37% Blacks, 62% Whites, 1% Other). Multiple intracranial stenoses were identified in 26% of patients with sICS (95% CI, adjusted Wald method:17.9%-36.5%). The most common locations of sICS included MCA (34.5%), intracranial ICA (15.5%), and vertebral artery (12%). Only basilar artery stenosis was more common in Blacks (16.1%) than Whites (1.9%; p=0.024).
Conclusions: Our study showed that approximately 1 out of every 4 AIS patients treated with tPA had sICS as the underlying mechanism of acute cerebral ischemia. Whether the persisting lesions represent partial recanalization of a thrombus or an underlying atheromatous stenosis deserve further investigation in a prospective multicenter study. Furthermore, this is the first report showing that sICS may be more common among Whites in the Stroke Belt of the U.S. than previously thought.
- Cerebrovascular disorders
- Intravascular ultrasound/Doppler
- Cerebrovascular circulation
- Acute stroke care
Author Disclosures: K.A. Sands: None. R. Bavarsad Shahripour: None. G. Tsivgoulis: None. M.J. Lyerly: None. G. Kumar: None. A. Sisson: None. P.V. Rawal: None. M. Alvi: None. N. Kapoor: None. J.T. Houston: None. A.V. Alexandrov: None.
- © 2014 by American Heart Association, Inc.