Table 1. Comparative summary of long-term risk stratification frameworks in KD: AHA 2017/2024 vs. JCS 2020

Variables	AHA 2017 [1]	AHA 2024 [3]	JCS 2020 [2]
Classification	5 levels (1–5) by max/current z-score; sub-levels for regressed aneurysm	Defines acute-phase high-risk (e.g., age ≤ 6 months or LAD/RCA z ≥ 2.5); clarifies follow-up cadence	z-score categories (small/medium/giant) + long-term status I–V emphasizing ischemia/stenosis
Antithrombotic emphasis	Escalate ASA/anticoagulation with risk level; giant CAA → ASA + warfarin/LMWH	Selective DOAC consideration in adult giant CAA	Similar intensity rules; anticoagulation in giant CAA

Practical implication: Both guidelines center on z-scores; AHA sharpens high-risk; JCS adds long-term status.
KD: Kawasaki disease; AHA: American Heart Association; JCS: Japanese Circulation Society; LAD: left anterior descending artery; RCA: right coronary artery; ASA: aspirin; CAA: coronary artery aneurysm; LMWH: low-molecular-weight heparin; DOAC: direct oral anticoagulant.