Aortic Arch Plaques and the Long-Term Risk of Stroke and Cardiovascular Events in the Statin Era

Abstract

BACKGROUND: Aortic arch plaques are associated with an increased risk of ischemic stroke in patients with cryptogenic stroke or prior embolic events. However, this relationship is unclear in the community. We investigated (1) the long-term risk of stroke and cardiovascular events associated with arch plaques and (2) whether statin therapy prescribed for any indication modified the association. METHODS: A total of 934 stroke-free participants (72±9 years; 37% men) from the CABL study (Cardiovascular Abnormalities and Brain Lesion) were evaluated. Arch plaques were assessed by suprasternal transthoracic echocardiography; plaques ≥4 mm in thickness were classified as large plaques. The primary outcome was ischemic stroke; the secondary outcome was combined cardiovascular events (ischemic stroke, myocardial infarction, and cardiovascular death). The plaque-related risk of outcomes was also analyzed according to the presence of statin treatment. No plaque was used as a reference. RESULTS: Aortic arch plaques were present in 645 participants (69.1%), with large plaques in 114 (12.2%). During a mean follow-up of 11.3±3.6 years, 236 (25.3%) cardiovascular events occurred (76 ischemic strokes, 27 myocardial infarctions, and 133 cardiovascular deaths). Large arch plaques were independently associated with combined events (adjusted hazard ratio, 2.19 [95% CI, 1.40–3.43]) but not stroke alone (adjusted hazard ratio, 1.09 [95% CI, 0.50–2.38]). The association between large plaques and cardiovascular events was significant in participants receiving statins (adjusted hazard ratio, 2.57 [95% CI, 1.52–4.37]) but not in others; however, participants on statin treatment also had a worse risk profile (higher body mass index, greater frequencies of hypertension, diabetes, and coronary artery disease). CONCLUSIONS: Aortic arch plaques may be a marker of cardiovascular risk rather than a direct embolic stroke source in older adults without prior stroke. The efficacy of broader cardiovascular risk factors control, beyond cholesterol levels alone, for primary prevention of cardiovascular events in individuals with aortic arch plaques may require further investigation.