Sequential Changes in Left Ventricular Systolic Myocardial Deformation Mechanics in Children with Recurrent Kawasaki Disease.

BACKGROUND: Sequential changes in left ventricular (LV) systolic function over time in patients with recurrent episodes of Kawasaki disease (KD) remain unclear. METHODS: Twenty-five children with recurrent KD were retrospectively studied. Using conventional echocardiographic parameters and myocardial deformation analysis, systolic LV function in children in initial and recurrent KD episodes were compared with separate control groups, comprising 15 controls each. Recurrent KD was defined as occurring at an interval of ≥2 months between the initial and recurrent episodes. RESULTS: The interval range between initial and recurrent episodes of KD was 3-103 months. In children with KD, 8 (32%) were <1 year of age at the initial episode, 10 (40%) had a recurrence within 1 year of the initial episode, and 4 (16%) and 5 (20%) were intravenous immune globulin nonresponders in initial and recurrent episodes, respectively. In both the initial and recurrent episodes of KD, the mean LV longitudinal peak systolic ε was all within normal range. However, when compared to controls, mean LV longitudinal peak systolic ε was decreased in patients with KD in the acute phases of both the initial and recurrent episodes. When compared to controls, mean LV longitudinal peak systolic ε was decreased in patients with KD in the convalescent phase of the recurrent episodes. CONCLUSIONS: Subclinical decreases in myocardial systolic deformation, as evidenced by decreased LV longitudinal peak systolic ε, may persist in children in the convalescent phase of recurrent KD; further studies involving larger numbers of patients may be needed for verification.

Clinical Utility of Left Atrial Strain in Children in the Acute Phase of Kawasaki Disease.

BACKGROUND: We aimed to evaluate the diagnostic utility of peak left atrial longitudinal strain (PALS) during left ventricular (LV) systole to differentiate children in the acute phase of Kawasaki disease (aKD) from controls. We also aimed to compare the diagnostic utility of PALS with those of conventional echocardiographic indices of diastolic function. METHODS: Retrospectively measured PALS, LV longitudinal peak systolic strain, and strain rate obtained via velocity vector imaging were compared in a derivation cohort comprising 95 aKD and 67 controls. The utility of PALS in differentiating aKD from controls was compared with those of E/E', E/A, and maximum left atrial volume index (LAVImax). Derived cutoffs from receiver operating characteristic curves were validated in a separate validation cohort comprising 37 aKD and 19 controls. RESULTS: In the derivation cohort, PALS was significantly decreased in aKD as compared with in controls. For differentiating aKD from controls, PALS outperformed E/E', E/A, and LAVImax. However, cutoffs of PALS (≤40% and ≤39%, before and after adjusting for the presence of significant mitral regurgitation and LV systolic dysfunction, respectively), like those of E/E', E/A, and LAVImax, showed low sensitivity and poor discriminative ability for differentiating aKD from controls. In the validation cohort, for differentiating aKD from controls, both cutoffs of PALS showed low sensitivity, like those of E/E', E/A, and LAVImax. CONCLUSION: In aKD, impaired left atrial reservoir function could be detected as decreased PALS. For differentiating aKD from controls, PALS outperforms E/E', E/A, and LAVImax. However, like E/E', E/A, and LAVImax, PALS as a single parameter is limited in its clinical utility to differentiate aKD from controls because of its low sensitivity and poor discriminative ability.