Journal of Nuclear Cardiology | 2019
Regional 18F-FDG uptake indicates coronary artery anomaly in a middle-aged patient with no atherosclerosis risk
Abstract
F-fluorodeoxyglucose (FDG) accumulates not only in malignant and inflammatory lesions but also in ischemic myocardium. We present a 41-year-old female with no atherosclerosis risk who showed an abnormal electrocardiogram (ECG) during a physical examination and abnormal wall motion in the left ventricle on echocardiography. The ECG showed sinus rhythm, QS pattern in lead V1-V3, and downsloping ST segment depressions in lead I, aVL, and V3-V6. The echocardiogram showed severe hypokinesis of the anterior wall, septal wall, and apex. Initially, she was suspected of having cardiac sarcoidosis and then F-FDG positron emission tomography (PET)/computed tomography (CT) was performed. She fasted for over 12 hours before the F-FDG PET/CT scan. Basal short-axis F-FDG PET image (Figure 1A), fused F-FDG PET/CT image (Figure 1B) and bull’s eye image using F-FDG (Figure 1C) showed diffusely increased uptake in the septal, anterior, and lateral walls of the left ventricle. Basal short-axis CT image revealed subendocardial fat deposition in the anterior and anterolateral wall of the left ventricle (Figure 1D). Ischemic cardiomyopathy was suspected from the F-FDG PET/CT findings. Coronary CT scan and stress/redistribution Tl cardiac singlephoton emission computed tomography (SPECT) were performed. CT image showed that the left coronary artery arose from the right cusp (Figure 2A). Left coronary artery traversed a course between the aorta and pulmonary artery, and artery stenosis was observed at this location (Figures 2A and B, arrows). SPECT and quantitative perfusion SPECT (QPS) images demonstrated a small irreversible defect and large reversible defect in the left coronary artery distribution region (Figure 3). She was finally diagnosed with anomalous left coronary artery originating from the right coronary cusp. Most congenital coronary artery anomalies appear to be of no clinical significance. However, coronary artery anomalies with an interarterial course, between the aorta and the main pulmonary artery, are likely to result in a higher incidence of angina, myocardial infarction, and sudden death. F-FDG accumulates in ischemic myocardium. Some case reports have noted incidentally observed focal abnormal F-FDG uptake in myocardium in oncologic patients with coronary artery disease. Even in the case of regional, as well as focal, accumulation, examination of the coronary artery seemed to be required.