Most population-based series reporting on the coronary artery complications after Kawasaki disease (KD) originate from Japan. This study aimed to describe the complete series of KD patients from the province of Quebec in Canada, a predominantly Caucasian population. This retrospective case series was conducted by the Quebec Kawasaki Disease Registry, a multi-institutional collaboration reviewing 89.8 % of all KD cases identified by the Ministry of Health records of hospitalization for KD from the first recognized case in 1976 until 2008. This report describes the course of 38 patients (95 % Caucasians) with a diagnosis of giant coronary artery aneurysms, which represent 1.9 % of all reviewed cases and 26.2 % of those with a coronary aneurysm 5 mm or larger. The age at diagnosis was 5.52 ± 4.04 years, and the follow-up period was 9.26 ± 6.9 years. The KD diagnosis was retrospective at autopsy in two cases and via echocardiography in four cases. The overall freedom from coronary thrombi, coronary intervention, or death was respectively 63.9, 67.5, and 85.1 %. Five deaths occurred as follows: 21 days after onset of fever (2 cases), 1.8 months after onset of fever (1 case), 1 year after retrospectively presumed but previously undiagnosed KD (1 case), and 5.7 years after a KD diagnosis (1 case of sudden cardiac death). Percutaneous transluminal coronary revascularization was attempted in four cases (1 requiring cardiac transplantation), and two other cases underwent primary bypass graft surgery. Whereas this study investigated cases of KD with severe coronary sequelae in the Province of Quebec, larger collaborative studies should be conducted for further understanding of the disease in predominantly non-Asian populations.
The long-term risk of patients with Kawasaki disease is not well defined. A great proportion of patients with Kawasaki disease have important variation of their coronary artery (CA) diameters, but the significance of this variation is not known. The aim of this study was to test the hypothesis that patients within the normal range of CA diameters but with important Z-score variation have a stronger inflammatory response and increased resistance to treatment than those without such Z-score variation.
A retrospective study was conducted in 197 patients with Kawasaki disease with serial echocardiograms up to 12 months after diagnosis. Patients with occult CA dilatation (variation > 2 Z-score units but within the normal range) were compared with patients with definite CA dilatation (Z score > 2.5) and with patients with normal CA for resistance to treatment and systemic inflammatory parameters.
A total of 63 patients (32.0%) were identified with Z scores always within the normal range but with important variation of CA diameter during follow-up (occult dilatation). There was a strong statistically significant trend of increasing inflammatory marker levels across patient categories (normal > occult dilatation > definite dilatation). Furthermore, resistance to intravenous immunoglobulin therapy was significantly increased in patients with occult dilatation compared with patients with normal CAs (relative risk, 2.6; 95% confidence interval, 1.21-5.44; P = .006).
The suggested definition of occult CA dilatation identified patients with CA involvement currently unrecognized per the current guidelines. These patients might be at a higher CA risk than previously thought.