Coronary artery dimensions may be misclassified as normal in Kawasaki disease.

BACKGROUND

Current American Heart Association guidelines indicate that patients with Kawasaki disease and no coronary artery abnormalities on echocardiography at any stage of illness may be discharged from cardiologic follow-up 1 year after onset of illness.

METHODS AND RESULTS

To determine whether coronary artery dimensions in patients with Kawasaki disease whose vessels are classified as "normal" by Japanese Ministry of Health criteria have a distribution similar to expected population norms when adjusting for body surface area, we studied 125 patients during 4 intervals from onset of illness: (1) 10 days or less, (2) 2 weeks (11 to 21 days), (3) 6 weeks (22 days to 3 months), and (4) 1 year (4 months to 1.5 years). Using two-dimensional echocardiography, we measured the internal lumen diameter of the left main, proximal left anterior descending, and proximal right coronary arteries. Mean body surface area-adjusted dimensions of the proximal left anterior descending and right coronary arteries were significantly larger (P < .01) in patients with Kawasaki disease than those in subjects in all periods, except for a marginal difference at 6 weeks for the proximal right coronary artery (P = .02); for the left main coronary artery, this difference achieved statistical significance in the period of 10 days or less, with a trend at 2 weeks (P = .02). Among patients classified as having normal coronary arteries on all echocardiograms by the Japanese Ministry of Health criteria, 27% had at least 1 body surface area-adjusted coronary dimension more than 2 standard deviations above the expected mean.

CONCLUSIONS

Coronary artery dilation in Kawasaki disease is thus more prevalent than previously reported, highlighting the need for systematic long-term surveillance of this population.