Coronary artery inflammation and aneurysm formation are the most common complications of Kawasaki disease (KD). Valvulitis and myocarditis are also well described and may lead to valvar regurgitation and left ventricular dysfunction. However, functional changes in the right heart have rarely been reported. We noted several acute KD patients with dilated pulmonary arteries (PA) and thus sought to systematically characterize PA size and right-heart function in an unselected cohort of KD patients cared for at a single clinical center. Clinical, laboratory, and echocardiographic data from 143 acute KD subjects were analyzed. PA dilation was documented in 23 subjects (16.1 %); these subjects had higher median right ventricle myocardial performance index (RV MPI), higher ratio of early tricuspid inflow velocity to tricuspid annular early diastolic velocity (TV E/e'), and lower median TV e' velocity compared to the non-PA dilation group (0.50 vs 0.38 p < 0.01, 4.2 vs 3.6 p < 0.05, and 13.5 vs 15.2 cm/s p < 0.01, respectively). Almost all subjects with PA dilation had improved PA Z-score, RV MPI, and TV E/e' in the subacute phase (p < 0.01). There were no significant differences in indices of left ventricle function between PA dilation group and non-PA dilation group. In summary, PA dilation was documented in 16 % of acute KD subjects. These subjects were more likely to have echocardiographic indices consistent with isolated RV dysfunction that improved in the subacute phase. The long-term consequence of these findings will require longitudinal studies of this patient population.
Keywords: Kawasaki disease; Myocardial performance index; Pulmonary artery dilation; Right ventricle function; Tissue Doppler imaging.