Evaluation of myocardial ischemia in Kawasaki disease using an isointegral map on magnetocardiogram

The authors have recently reported on the usefulness of the isointegral mapping technique using magnetocardiography (MCG) for the diagnosis of adult ischemic heart disease. This study evaluated myocardial ischemia in patients with Kawasaki disease (KD). The ischemia has been considered difficult to diagnose with a standard ECG. The study included 32 patients (age 3 +/- 22 years, mean 12.9 +/- 4.1 years, +/- SD) with a history of KD and 21 age-matched healthy children. Coronary arterial lesions were present in 13 patients of the KD group, MCG was carried out at rest with a multichannel superconducting quantum interference device (SQUID) system. The integral value was computed for each channel and isointegral maps were constructed during depolarization and repolarization processes. In all subjects of the control group, the integral value of repolarization was higher than that of depolarization and the isointegral map of these two processes showed similar patterns. However, the integral value of repolarization in four cases with KD (one with a history of myocardial infarction, two with a stenotic lesion in the left coronary artery, one with an aneurysmal and stenotic lesion in the right coronary artery) was lower than that of depolarization, and abnormal patterns were evident in the isointegral map. All but the case with myocardial infarction showed only mild abnormalities or almost normal on the ECG. Although sensitivity of the method for detection of myocardial ischemia was not fully assessed because of the small number of cases with significant coronary arterial stenosis, noninvasive isointegral mapping technique using the MCG could be useful for evaluation of myocardial ischemia in patients with KD.