In patients with Kawasaki disease who develop coronary artery stenosis or ischemia, what are the indications for revascularisation and the preferred surgical (coronary artery bypass grafting) versus percutaneous (PCI) approaches based on age, aneurysm size, and lesion characteristics?

Revascularization in Kawasaki Disease

For patients with Kawasaki disease requiring revascularization, CABG is strongly preferred over PCI for left main disease, multivessel disease, chronic total occlusions, reduced LV function, diabetes, or age >12 years, while PCI is reasonable only for single-vessel disease with focal lesions and normal LV function 1.

Clear Indications for Revascularization

The 2017 AHA guidelines provide specific Class I indications 1:

• High-risk coronary anatomy: Left main disease, multivessel disease with reduced LV function, multivessel disease with diabetes, or high-risk noninvasive ischemia testing
• Non-STEMI with amenable coronary anatomy on angiography
• Remote KD history presenting with STEMI: Emergent coronary angiography for flow restoration

Class IIa (reasonable): Stable angina refractory to maximal medical therapy

Class IIb (may be considered): Silent ischemia involving >10% of LV mass

Critical caveat: Avoid revascularization during acute/subacute KD phase with STEMI from acute thrombotic occlusion (Class III) 1. This is fundamentally different from atherosclerotic disease.

CABG vs PCI Decision Algorithm

Choose CABG for:

1. Left main coronary involvement (most important factor)
2. Multivessel disease - achieves more complete revascularization
3. Chronic total occlusions (≥1 present)
4. Reduced LV function from prior MI or chronic ischemia
5. Diabetes mellitus - extrapolating from FREEDOM trial showing survival benefit
6. Failed PCI or PCI-unfeasible anatomy
7. Age >12 years or older children/young adults - better graft patency 1

Choose PCI for:

1. Single-vessel disease with focal, easily treated lesions
2. Normal LV function
3. No diabetes
4. Younger age (<12 years where CABG graft patency is reduced) 1

Critical Technical Considerations for CABG

Use both internal mammary arteries (IMAs) as conduits whenever possible 1. This is non-negotiable for optimal outcomes:

• IMA patency rates (age >12 years): 95% at 1 year, 91% at 5 and 15 years
• IMA patency rates (age ≤12 years): 93% at 1 year, 73% at 5 years, 65% at 15 years
• Saphenous vein graft patency: Only 65% at 5 years, 53% at 10 years, 48% at 15 years

Avoid saphenous vein grafts - they don't grow with children and have inferior long-term patency 2.

Important pitfall: Only use IMA grafts for vessels with physiological stenoses (documented ischemia). Grafting angiographically borderline lesions without proven ischemia leads to graft failure from competitive flow. Consider FFR assessment if ischemia testing is negative 1.

PCI Outcomes and Limitations

PCI has significantly higher reintervention rates compared to CABG. Japanese data shows PCI requires repeat revascularization in a substantially higher proportion of patients 3. A Canadian series found no patients needed reintervention after CABG versus 6 after PCI (p=0.004) 4.

PCI technical challenges in KD 5, 6:

• Severe coronary calcifications require rotational ablation
• Stentless PCI (balloon angioplasty or rotablator) used more often than in atherosclerotic disease
• High-pressure balloon inflation risks new aneurysm formation - a unique KD complication
• Best results within 6 years of disease onset; restenosis rates remain high

Age-Specific Considerations

Age >12 years: CABG strongly favored - superior IMA graft patency (91% at 15 years) and better long-term outcomes 1

Age ≤12 years: Decision more nuanced - IMA patency drops to 65% at 15 years, but CABG still preferred for multivessel disease. PCI may be considered for single-vessel focal lesions, though reintervention rates are higher 4, 3

First decade of life: CABG has been performed successfully, though technically challenging 1

Complications and Prognosis

CABG complications mirror adult atherosclerotic disease (1-2% risk of death, MI, major bleeding, stroke, renal failure), but KD patients fare better due to younger age and absence of diffuse atherosclerosis 1.

Long-term CABG outcomes are favorable with normal LV function predicting better survival 1.

AMI in KD requires more intensive therapy than atherosclerotic AMI, including mechanical support (IABP, ECMO, ventilator) and cardiopulmonary resuscitation more frequently, despite similar in-hospital mortality 6.