**11. Further imaging modalities**

As the difficulty of coronary artery imaging increases with age, further imaging options may be necessary. Even in experienced hands, echocardiography also has its limitations in detecting stenosis and thrombosis. The efficacy of other non-invasive imaging modalities such as magnetic resonance imaging and multi-detector computed tomography has been increasingly evaluated for coronary artery assessment in Kawasaki disease (Figure 7).

Myocardial inflammation may also involve valve tissue and lead to mitral, tricuspid or aortic regurgitation that is usually mild in nature. If severe mitral regurgitation is present, papillary muscle dysfunction and myocardial ischaemia should be assessed (Akagi et al., 1990). Mild aortic regurgitation is seen to persist in approximately 4% of patients with serial follow-up (Ravekes et al., 2001). Aortic root dilatation may occur as part of the overall

The consensus statement from the American Heart Association recommends performing echocardiography at diagnosis, 2 weeks and repeating at 6-8 weeks after the onset of illness for uncomplicated cases. In some centres the 2 week echocardiogram is not routinely performed. The imaging at diagnosis should provide a baseline study for serial follow-up of left ventricular function, coronary arterial involvement, valvar regurgitation, myocarditis and/or a pericardial effusion. The presence of any cardiac involvement warrants closer followup. In particular, coronary aneurysms > 5mm in size require close monitoring because of an elevated risk of developing stenotic lesions within the vessel (Mueller, 2009). By 6-8 weeks, transient cardiac involvement is likely to have resolved, or if coronary artery dilation and/or

A number of definitions have been proposed to describe and quantitate coronary artery involvement. The Japanese Ministry of Health classification was first published in 1984. Aneurysms are considered to be small if their internal diameter is <5mm, medium if between 5-8mm, or giant if the internal diameter of the aneurysm is >8mm (Figure 5). These criteria are widely used and define absolute values for coronary artery dimensions and therefore do not account for differences in patient size or the usual caliber of different coronary artery branches. The American Heart Association AHA guidelines were published in 2004 and define coronary artery dimensions with respect to body surface area, which requires both weight and height measurements. These define a coronary artery as dilated if the intra-luminal diameter has a z-score of ≥ 2.5mm. Manlhiot et al. recently proposed a revision of this classification to account for differences in body size and caliber of coronary artery branches, and report that coronary artery abnormalities are small if the z-score is ≥ 2.5 to <5, large if the z-score is ≥ 5 to < 10, and giant if the z-score is ≥ 10 (Manlhiot et al., 2010). This method is however prone to significant variation in the calculated z-score with minor variation in measurement of coronary size. It is therefore too early to determine whether this

As the difficulty of coronary artery imaging increases with age, further imaging options may be necessary. Even in experienced hands, echocardiography also has its limitations in detecting stenosis and thrombosis. The efficacy of other non-invasive imaging modalities such as magnetic resonance imaging and multi-detector computed tomography has been increasingly evaluated for coronary artery assessment in Kawasaki disease (Figure 7).

aneurysms are present, the maximum diameter is usually reached by this time.

**10. Definitions of coronary artery involvement** 

classification will be widely employed.

**11. Further imaging modalities** 

**8.3 Valvar involvement** 

vasculitis but is usually mild.

**9. Timing of echocardiography** 

Fig. 7. Magnetic resonance image using T2 weighted truFISP sequence demonstrating a dilated left anterior descending (LAD) artery with a distal fusiform aneurysm.
