PURPOSE: The purpose of this study is to assess myocardial function in infant Kawasaki disease, with strain and tissue Doppler imaging, in addition to conventional echocardiographic measures. METHODS: Strain and tissue Doppler imaging were performed in 20 patients with infant Kawasaki disease. Peak velocities of systolic and early, late diastolic pulsed tissue Doppler velocities, strain, and time to peak strain values were measured at ventricular septal annulus from apical view. The data set were obtained at both acute period and convalescent period. RESULTS: All patients represents coronary arteriopathy. Measures of Systolic peak velocity (S') of pulsed wave tissue Doppler value and strain decreased in convalescent phase, and time to peak strain was delayed (P<0.01). Meanwhile, the diastolic measures (E' and A') demonstrated no significant differences between acute and convalescent phases using tissue Doppler velocity data. CONCLUSION: In convalescent phase, myocardial systolic function may not be completely improved yet. After convalescent period, continuous myocardial assessment should be followed.