On echocardiography, a coronary artery aneurysm in Kawasaki disease is classified as GIANT when the internal lumen diameter measures:
- A Greater than or equal to 4 mm
- B Greater than or equal to 8 mm ✓
- C Greater than or equal to 6 mm
- D Any diameter with a Z-score greater than 2.5
Correct answer: B. Greater than or equal to 8 mm
Explanation
Giant aneurysms are defined as an absolute internal diameter of 8 mm or more, or a Z-score of 10 or greater. Small aneurysms are less than 5 mm and medium aneurysms 5 to 8 mm. Giant aneurysms carry the highest risk of thrombosis, stenosis, and myocardial infarction and usually warrant anticoagulation with warfarin or low molecular weight heparin in addition to antiplatelet agents. A Z-score above 2.5 alone defines aneurysm presence, not giant size.
Reference: Nelson Textbook of Pediatrics, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.