3D carotid ultrasound in patients with a negative exercise stress test:A practical risk stratification tool

Background: Exercise stress tests (EST) are frequently used to evaluate chest pain. While a negative EST is reassuring, further risk stratification for coronary artery disease (CAD) may be warranted. Three-dimensional (3D) carotid ultrasound is a non-invasive tool which can be used to identify subclinical atherosclerotic disease. We investigated the prevalence and extent of subclinical atherosclerotic lesions using 3D carotid ultrasound in patients with chest pain and a negative EST, with the aim of understanding the changes in atherosclerotic lesions with statin therapy at 1 year. Methods: 80 patients were prospectively enrolled and all received additional vascular assessment with 3D carotid ultrasound. If subclinical atherosclerosis was identified, high-dose statin therapy was recommended. A 3D carotid ultrasound scan was repeated at 12 months. Results: Of our cohort, 37 patients (46.3%) had carotid plaque. At baseline, median plaque volume (IQR) (left carotid, right carotid, or both) was 32.0 mm3 (17-123). At 12-month follow-up (n=22), median plaque volume was 116.0 mm3 (46-279) (p=0.004). Of these, only 40.9% were on high-dose statin therapy. Total plaque volume remained stable in subjects on statins (46.5 mm3 [25-97.5] at baseline; 50 mm3 [29-131] at 12 months, p=0.596) while it increased in those without statins (20 mm3 [10-31] at baseline; 117 mm3 [78-279] at 12 months, p=0.003). Conclusion: In patients with chest pain and a negative EST, roughly one-half have subclinical atherosclerosis as detected with 3D carotid ultrasound. Plaque progression commonly occurs at 12 months, but is less likely with statin therapy. A further randomized study is required to confirm our findings.