Background: One of the main impediments to conceiving and planning studies in children with coronary artery aneurysms (CAA) after Kawasaki disease (KD) is the lack of normative data regarding the prevalence of outcomes over time and risk factors.
Methods: The North American Kawasaki Disease Registry was used to determine the prevalence of multiple clinically important outcomes of CAA after KD. All analyses were stratified by severity of CAA (small CAA with z-score = 2.5-5, medium with z-score = 5-10 and giant with z-score >10). All analyses were performed using non-parametric survival analysis.
Results: n=621 patients submitted to the Registry had complete follow-up data and were included in the analysis (280 [45%] small CAA, 139 [22%] medium and 202 [33%] giant). Time-related freedom from multiple outcomes stratified by type of CAA are reported in the Table. Reduction in z-scores was strongly associated with the initial size of the lesion, with smaller lesions being more likely to decrease to a normal dimension over time. Thrombosis and stenosis were infrequent in patients without giant CAA. For those patients with giant CAA, the risk of thrombosis, myocardial infarction, angiographically-confirmed stenosis and revascularization was substantial and persisted up to 10 years after diagnosis. In addition to larger luminal diameter, other factors associated with increased risk of adverse outcomes included larger CAA longitudinal area and complex CAA (vs. isolated lesions).
Conclusions: Only patients with giant CAA are at substantial risk of adverse clinical outcomes; future trials of pharmacological therapy targeting thrombosis and stenosis risk should focus on these patients.