Importance of blood pressure control in Kawasaki disease with expanded multiple giant coronary aneurysms with a 32 mm maximum diameter: a case report

BACKGROUND: Ruptured coronary artery aneurysm is rare, but the most serious complications of an acute phase of Kawasaki disease (KD) with giant coronary artery aneurysm (GCAA). Progressive or super GCAA, which rapidly dilates and continue to increase over a diameter of 10 mm, are more susceptible to rupture. CASE SUMMARY: We report the case of a 6-year-old boy with KD who had multiple super GCAAs with a high risk of GCAA rupture. On admission to our hospital, he presented with fever, chest pain, and Stage II hypertension. Echocardiographic Z-scores adjusted for body surface area were used for measurements. The coronary artery diameter of segment 1 was 24.3 mm with a Z-score of 20.8; the diameter of segment 3 was 24.4 mm; the diameter of the left anterior descending branch was 32.6 mm with a Z-score of 20.1. The super GCAAs showed a tendency to expand compared to the latest echocardiography, and thrombus formation was observed in the super GCAA of segment 3. The patient was treated with anti-inflammatory therapy, antithrombotic therapy, and antihypertensive therapy with continuous arterial pressure monitoring with the goal of not exceeding the 5th percentile of the normal standard during the period when there was a risk of progressive coronary aneurysm expansion. He was discharged without any neurological complications. DISCUSSION: We speculated that the patient's hypertension was the cause of an expanding coronary artery aneurysm. In conclusion, KD patients with super GCAA may benefit from aggressive blood pressure control with continuous arterial pressure monitoring.