Magnetic Resonance Angiography is Equivalent to X-ray Coronary Angiography for the Evaluation of Coronary Arteries in Kawasaki Disease

Objectives: The purpose of this study was to compare the results of magnetic resonance angiography (MRA) with X-ray coronary angiography (XCA) in a pediatric population.

Background: Coronary artery abnormalities in Kawasaki disease (KD) develop in about 15% to 25% of young patients, mostly in the form of aneurysms.

Methods: Thirteen patients (12 male), age three to eight years, were studied. The maximal diameter and length of the aneurysm were recorded. Coronary MRA was performed using a 1.5 T Philips Intera CV magnetic resonance scanner with an electrocardiographically triggered pulse sequence. It was a three-dimensional segmented k-space gradient-echo sequence (TE = 2.1 ms, TR = 7.5 ms, flip angle = 30 degrees, slice thickness = 1.5 mm) employing a T2-weighted preparation pre-pulse and a frequency selective fat-saturation pre-pulse. Data acquisition was performed in mid-diastole. All scans were carried out with the patient free breathing using a two-dimensional real-time navigator beam. All patients underwent XCA within a week.

Results: In six patients, aneurysms of the coronary arteries were identified, while coronary ectasia alone was present in the remaining seven patients. Magnetic resonance angiography and XCA diagnosis of coronary artery aneurysm agreed completely. Maximal aneurysm diameter and length and ectasia diameter by MRA and XCA were similar. No stenotic lesion was identified by either technique.

Conclusions: In conclusion, MRA is a reliable diagnostic tool, equivalent to XCA for coronary artery aneurysm identification in patients with KD. Magnetic resonance angiography may prove to be of great value for the serial non-invasive evaluation of these patients.