Background: As a result of the acute vasculitis associated with Kawasaki disease (KD), subsets of patients with a remote history of KD have coronary artery aneurysms and may develop coronary artery stenoses with associated risks of late morbidity. Hence, there is a need for effective non-invasive testing to detect coronary artery pathology and risk stratify patients with a remote history of KD. In a pilot study we previously showed that computed tomography (CT) coronary artery calcium (CAC) scoring with relatively low radiation doses detects late CAC in patients with aneurysms and a remote history of KD.
Methods: We performed CT calcium volume scoring in 166 subjects (median age 19.5 years) with a remote history of KD (median interval from onset of KD to CT 15.1 years). Coronary arteries were classified as normal (n = 100), transiently dilated (n = 23), persistently dilated (n = 10), resolved aneurysm (n = 9), or aneurysm (n = 24) based on the initial echocardiograms. We defined coronary artery pathology as the presence of a coronary artery aneurysm or stenosis.
Results: All subjects with coronary arteries classified as normal, persistently dilated, or resolved aneurysm had zero CAC. All but one of the subjects with transiently dilated coronary arteries had zero CAC (the one subject with a CAC score of 666 mm3 had a history of severe left main coronary artery stenosis requiring bypass surgery). Of the 24 subjects with coronary aneurysms, all but 5 had CAC (median volume score 542 mm3; range 17 mm3 to 8,218 mm3). Four of the 5 subjects with aneurysms and no CAC were imaged within 6 years of their episode of acute KD. For subjects imaged 9 or more years after their acute KD (n=144), the presence of CAC on CT had a sensitivity of 95% and a specificity of 100% for detecting coronary artery pathology.
Conclusions: For patients with a remote history of KD, CT calcium scoring is a sensitive and specific test for detecting coronary artery pathology. Patients with coronary artery aneurysms secondary to KD develop late CAC, which may be severe. The pathophysiology and clinical significance of this calcification are currently unknown.