To analysis the difference between the application of high-frequency probe and the use of low-frequency probe in detecting the coronary arteries in children by using echocardiography, including the imaging quality, inner diameter of the coronary artery, and coronary artery dilation to facilitate clinical diagnosis.

From November 2014 to November 2015, 215 children who were diagnosed as Kawasaki disease, underwent echocardiography examination in Capital Institute of Pediatrics. Twelve cases did the examination of the computed tomography angiography and echocardiography using high-frequency probe (S12-3) and the low-frequency probe (S5-1). The imaging quality, coronary artery size and the number of coronary artery dilation were compared after the examination.

The imaging obtained by the use of high-frequency probe showed stronger contrast, higher resolution than using the lower-frequency probe. The opening of left and right coronary artery and the proximal part were showed extremely clear and the imaging of intima was echo-homogeneous. While the imaging of the low-frequency probe for young children, especially for babies was discovered poorly, with blurred intima and ill-defined margin. The diameter of coronary artery in high-frequency probe imaging was not significant different with CT images (P>0.05), but the data obtained from the low-frequency probe [(2.95±1.36) mm, (2.24±1.27) mm, (1.89±2.63) mm, (2.35±2.89) mm] was different with CT [(2.67±0.42) mm, (2.03±0.64) mm, (1.56±0.48) mm, (2.07±0.47) mm] (P<0.05). The maximum number of coronary artery dilation got from CT, second was that from the use of low-frequency probe, and followed by the use of high-frequency probe.

The high-frequency probe was more suitable for detecting coronary artery disease in KD infants. The images were more distinctewith more reliable data, and the examination was non-invasive, safe, and convenient.It was more appropriate for the diagnosis ofacute phase Kawasaki disease and patient follow-up in clinic.