Abstract
BACKGROUND Aortic atherosclerosis represents an important contributor to ischemic stroke risk. Identifying patients with high-risk aortic atheroma could improve preventative treatment strategies for future ischemic stroke.
OBJECTIVES The purpose of this study was to investigate whether thoracic F-18-sodium fluoride positron emission tomography (PET) could improve the identification of patients at the highest risk of ischemic stroke.
METHODS In a post hoc observational cohort study, we quantified thoracic aortic and coronary F-18-sodium fluoride activity in 461 patients with stable cardiovascular disease undergoing PET combined with computed tomography (CT). Progression of atherosclerosis was assessed by change in aortic and coronary CT calcium volume. Clinical outcomes were determined by the occurrence of ischemic stroke and myocardial infarction. We compared the prognostic utility of F-18-sodium fluoride activity for predicting stroke to clinical risk scores and CT calcium quantification using survival analysis and multivariable Cox regression.
RESULTS After 12.7 +/- 2.7 months, progression of thoracic aortic calcium volume correlated with baseline thoracic aortic F-18-sodium fluoride activity (n =140; r = 0.31; P = 0.00016). In 461 patients, 23 (5%) patients experienced an ischemic stroke and 32 (7%) a myocardial infarction after 6.1 +/- 2.3 years of follow-up. High thoracic aortic 18F-sodium fluoride activity was strongly associated with ischemic stroke (HR: 10.3 [95% CI: 3.1-34.8]; P = 0.00017), but not myocardial infarction (P = 0.40). Conversely, high coronary F-18-sodium fluoride activity was associated with myocardial infarction (HR: 4.8 [95% CI: 1.9-12.2]; P = 0.00095) but not ischemic stroke (P = 0.39). In a multivariable Cox regression model including imaging and clinical risk factors, thoracic aortic 18F-sodium fluoride activity was the only variable associated with ischemic stroke (HR: 8.19 [95% CI: 2.33-28.7], P = 0.0010).
CONCLUSIONS In patients with established cardiovascular disease, thoracic aortic F-18-sodium fluoride activity is associated with the progression of atherosclerosis and future ischemic stroke. Arterial F-18-sodium fluoride activity identifies localized areas of atherosclerotic disease activity that are directly linked to disease progression and down-stream regional clinical atherothrombotic events. (C) 2022 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.