de Ferranti SD, et al. - Researchers evaluated the benefit of additional echocardiographic imaging at 6 weeks in patients with uncomplicated Kawasaki disease who had previously normal coronary arteries. At 6 weeks, new abnormalities in coronary arteries are rarely detected in patients with Kawasaki disease who have normal measurements at baseline and 2 weeks of illness. This suggested that in patients with uncomplicated Kawasaki disease and z scores less than 2.0 in the first 2 weeks of illness, the 6-week echocardiographic imaging may be unnecessary.

Methods

• Experts conducted a retrospective review of patients with Kawasaki disease who were cared for between 1995 and 2014 in 2 academic pediatric referral practices.
• The eligibility criteria included receiving intravenous immunoglobulin treatment for acute Kawasaki disease at a center; the absence of significant congenital heart disease; available echocardiographic measurements of both the right and left anterior descending coronary arteries at 10 days or less after diagnosis (baseline), 2 (±1) weeks, and 6 (±3) weeks of illness; and normal coronary arteries at baseline and 2 weeks, defined as maximum coronary artery z scores less than 2.0 and no distal aneurysms.
• They completed the data analysis from March 2015 to November 2015.
• The number of patients with right coronary artery or left anterior descending coronary artery z scores of 2.0 or more at 6 weeks were the main outcomes and measures.

Results

• Findings suggeted that the median age of the 464 included patients was 3.3 years (interquartile range, 1.8-5.4 years); 264 (56.9%) were male, 351 of 414 for whom data were available (84.8%) had complete Kawasaki disease, and 66 (14.2%) received additional intravenous immunoglobulin treatment.
• As per data, at 6 weeks of illness, 456 patients (98.3%) who had had normal coronary artery z scores at baseline and 2 weeks continued to have normal z scores.
• Results demonstrated that out of the remaining 8 patients (1.7%), the maximum z score within 6 weeks was 2.0 to 2.4 in 5 patients (1.2%), 2.5 to 2.9 in 1 patient (0.2%), and 3.0 or more in 2 patients (0.4% [95% CI, 0.1%-1.5%]).
• Ultimately, the coronary artery dimensions normalized in all but 1 patient, who had minimal dilation at 6 weeks (right coronary artery z score, 2.1).
• They noted similar results of the sensitivity analyses using less restrictive cut points (eg, a maximum z score <2.5) or less restrictive timing windows (eg, considering patients with incomplete echocardiographic data within 21 days) ; in these analyses, 454 to 463 of 464 patients (98% to 99.7%) had coronary artery z scores of less than 2.5 at 6 weeks.