Table 1

Classification of coronary artery dilation or aneurysms (after AHA guidance with modification)11

Classification of risk levelDescription of coronary arteriesFollow-up intervalImaging required to assess for inducible ischaemia (stress echo or stress MRI)PSPRegional specialist Kawasaki disease clinic
1No involvement at any time point
(Z score<2)		2 weeks
6 weeks
6 months
12 months
Discharge if normal at 12 months.		NoneNoNo—annual cardiac and general health review with GP recommended*
2Dilation only
(2<Z score≤2.5): resolves within 1 year		2 weeks
6 weeks
6 months
12 months
Discharge if normal at 12 months		NoneNoNo—annual cardiac and general health review with GP recommended*
3Small aneurysm (2.5≤Z score<5):
(a) current or persistent,
(b) decreased to normal or Z score <2.5		2 weeks
6 weeks
6 months
12 months
Annual review		Coronary angiography (preferably CT) at 12 months as baseline.
Consider stress imaging for inducible myocardial ischaemia every 2 years.
Imaging (echo) for coronary surveillance annually		YesYes
4Medium aneurysm (5≤Z score<10):
(a) persistent aneurysm,
(b) decreased to normal or Z score<2.5		2 weeks
6 weeks
6 months
12 months
Annual review		Coronary angiography (preferably CT) at 12 months as baseline.
Consider stress imaging for inducible myocardial ischaemia annually. Imaging (echo, CT† or MRI) for coronary thrombus surveillance annually.		YesYes
5Giant aneurysm (Z score≥10 or ≥8 mm):
(a) persistent giant aneurysm,
(b) persistent aneurysm (but regressed to medium or small aneurysms),
(c) regressed to normal dimensions		2 weeks
6 weeks
3 months
6 months
9 months
12 months
Then every 6 months		Coronary angiography (preferably CT) at 6–12 months as baseline.
Consider stress imaging for inducible myocardial ischaemia annually.
Imaging (echo, CT† or MRI) for coronary thrombus surveillance 6 monthly.		YesYes

  • *GP review should include clinical examination, blood pressure measurement, general health discussion and advice on avoidance of cardiovascular risk factors and lifestyle choices—including maintaining a healthy weight, reducing risk of diabetes, avoiding smoking and taking regular exercise. This provides the opportunity to discuss any parent or patient questions and concerns.

  • †CT should not be used repeatedly if possible. Use MRI or ultrasound where possible, to reduce radiation exposure.

  • ADP, Adenine di-Phosphate; AHA, American Heart Association; FBC, Full blood count; GP, General Practioner; PSP, person-specific protocol.