Risk of Stroke in Imaging-proven Subclavian Steal Syndrome (P1.067)

Background: The purpose of this study was to determine the risk of stroke in subclavian steal syndrome (SSS). Methods: We performed a retrospective cohort study of patients with imaging-proven SSS between 2009 and 2014. Imaging evidence of SSS was defined as complete occlusion of the subclavian artery or partial occlusion with flow reversal in the vertebral artery on CTA, MRA, DSA or US. Results: We identified 332 patients by searching the ICD-9 code for SSS (435.2), of which 126 satisfied the inclusion criteria. 39[percnt] had complete occlusion of subclavian artery, while 61[percnt] had partial occlusion. The presenting symptoms were dizziness/vertigo/syncope (42[percnt]), arm pain/weakness/numbness (17[percnt]), chest pain after CABG (2[percnt]), and both dizziness and arm symptoms (6[percnt]). SSS was discovered incidentally in 33[percnt] of the patients. 40[percnt] underwent treatment (74[percnt] stents, 12[percnt] bypass). Symptomatic patients were more likely to be treated (46 vs. 28[percnt], p=0.05). Our follow-up rate was 78[percnt] with a median follow-up of 18 months. There were 23 cases of stroke (39[percnt] anterior, 52[percnt] posterior, 4[percnt] both). Male gender (87 vs. 55[percnt], p=0.005) and no treatment (26 vs. 49[percnt], p=0.049) were associated with stroke. We found no association between stroke and age (61 vs. 63 yrs, p=0.59), presence of symptom (83 vs. 65[percnt], p=0.11), difference in SBP>20 mmHg between two arms (58 vs. 57[percnt], p=0.94), symptom during follow-up (62 vs. 43[percnt], p=0.22), subclavian artery occlusion (24 vs. 40[percnt]. P=0.19), and severe carotid stenosis (77 vs. 63[percnt], p=0.49), and severe vertebral stenosis (60 vs. 74[percnt], p=0.44). None of the cardiovascular risk factors was associated with stroke. On multivariate logistic regression, male gender (p=0.009) and presence of symptoms (p=0.048) predicted for stroke. Conclusion: The risk of stroke, especially of the posterior circulation, is high in patients with imaging-proven SSS. Male gender and presenting with symptoms were predictive risk factors for stroke. Disclosure: Dr. Bai has nothing to disclose. Dr. Wang has nothing to disclose. Dr. Zou has nothing to disclose. Dr. Zhao has nothing to disclose. Dr. Zhou has nothing to disclose. Dr. Xiao has nothing to disclose. Dr. Shu has nothing to disclose. Dr. Chou has nothing to disclose. Dr. Bo has nothing to disclose. Dr. Kasner has nothing to disclose. Dr. Tan has nothing to disclose. Dr. Li has nothing to disclose.