Magnetic resonance imaging of old myocardial infarction in young patients with a history of Kawasaki disease.

BACKGROUND: On magnetic resonance imaging (MRI) using gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) as contrast medium, images of infarct regions are enhanced in acute myocardial infarction (AMI). In old myocardial infarction (OMI), thinning of the myocardial walls is present, but images are no longer enhanced by Gd-DTPA. On the other hand, MI in children with a history of Kawasaki disease (KD), several differences from adult MI are observed.

HYPOTHESIS: The aim of this study was to evaluate the lesions that result from OMI in children with a history of KD using MRI with Gd-DTPA as a contrast medium.

METHODS: The subjects were 16 young patients with a history of KD who were diagnosed as having OMI. Of these, both thinning of the myocardial wall and MRI enhancement by Gd-DTPA were observed in 4 cases, thinning alone was observed in 6 cases, Gd-DTPA image enhancement alone was observed in 3 cases, and neither thinning nor Gd-DTPA image enhancement was observed in 3 cases.

RESULTS: The Gd-DTPA-image-enhanced, OMI-induced lesions observed in patients with KD were different from those observed in adults; this might be attributable to histologic differences.

CONCLUSION: Magnetic resonance imaging using Gd-DTPA can evaluate myocardial thinning and presence of circulation noninvasively at the same time and is considered to be useful for long-term follow up of the patients with KD and OMI.