Improved Classification of Coronary Artery Abnormalities Based Only on Coronary Artery z-Scores After Kawasaki Disease

Abstract

Competing definitions and classifications of coronary artery abnormalities (CAAs) after Kawasaki disease (KD) have been arbitrarily defined based on clinical experience. We sought to propose a classification system for CAAs based only on coronary artery z-scores. All echocardiograms performed between 1990 and 2007 on patients with a previous history of KD were reviewed. Coronary artery luminal dimensions were converted to body-surface-area-adjusted z-scores and compared to current classification systems. A total of 1356 patients with a previous history of KD underwent 4379 echocardiograms. There was important overlap in the distributions of coronary artery z-scores between the different CAA classes as defined by the American Heart Association (AHA). The AHA classification underestimated the severity of CAAs in 19-32% of small CAAs and 35-78% of medium CAAs. We determined the optimal definition of CAA to be small if the z-score is >or=2.5 to <5.0, large if the z-score is >or=5.0 to <10.0, and giant if the z-score is >or=10.0. This classification seems to appropriately apply to the circumflex branch despite a lack of normal values for this branch. The current AHA classification might not accurately classify CAAs in KD patients. Accurate classification is important for defining management and prognosis consistently across patient age and size.

Diagnosis, Treatment, and Long-Term Management of Kawasaki Disease: A Scientific Statement for Health Professionals From the American Heart Association

“…Manlhiot et al proposed a classification scheme based solely on Z scores using the formulas provided in the study from the National Heart, Lung, and Blood Institute Pediatric Heart Network. 139,140 One potential limitation of this study is that regression formulas for the LAD were used to derive Z scores for the left circumflex branch (normal values for the circumflex are not available with the Z-score system that was used). A classification scheme based solely on Z scores was proposed, which has been adapted and recommended in these guidelines:…”

“…158,159,175 An even greater percentage of patients (30%) will be classified as having coronary artery dilation when a Z-score cut point of 2.0 is used to define dilation. 111,140,176 Additional therapies of potential benefit are discussed below, but optimal treatment awaits delineation of the specific agent(s)/trigger(s) and pathogenesis of KD. ; thus, ibuprofen generally should be avoided in children with coronary artery aneurysms taking ASA for its antiplatelet effects.…”

Carotid Intima-Media Thickness in Patients With a History of Kawasaki Disease

“…We defined CAA by worst-ever z-scores: CA dimensions as standard deviation units normalized for basal surface area. 20, 21 We choose to define the CAA by their worst-ever score because even when the lumen of a previously affected coronary artery has returned to its normal size, the artery can still be damaged and thus the initial systemic vasculitis was clearly more severe when compared with children with normal-sized arteries who had never had any enlargement at all. CAA was defined as a coronary z-score ≥2.5, a giant aneurysm was defined as a z-score ≥10 or a diameter ≥8 mm.…”

Enfermedad de Kawasaki: Consenso interdisciplinario e intersociedades

“…Una lesión con un puntaje Z ≥ 10 debería tratarse como un aneurisma gigante por más que su valor absoluto sea menor de 8 mm. 37 Evaluación ecocardiográfica de lesiones no coronarias: se debe determinar el diámetro del VI en sístole y diástole, además de su fracción de acortamiento y de eyección. 38 La insuficiencia mitral se encuentra en un 27% de los pacientes; la insuficiencia aórtica, en 5%; la dilatación de la raíz aórtica, en 10%; 38 la pericarditis, en 5%; y algunos pueden desarrollar taponamiento cardíaco.…”