Characteristics of myocardial18F-fluorodeoxyglucose positron emission computed tomography in dilated cardiomyopathy and ischemic cardiomyopathy

Abstract

Myocardial 18F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) has been used to assess myocardial ischemia and viability, but few studies have conducted on FDG-PET for dilated cardiomyopathy (DCM). We investigated myocardial FDG uptake in patients with DCM in comparison with ischemic cardiomyopathy (ICM). Twenty-four patients with heart failure were included in this study. Fourteen of them were diagnosed as DCM and the other 10 were ICM. All of them underwent myocardial FDG-PET at fasting and after glucose loading the same day. FDG uptake was quantified by the ratio of the counts at the heart to those at the liver (H/L ratio). Left ventricular (LV) function was measured by echocardiography. We classified FDG distribution patterns in the myocardium in the fasting state into 3 types (faint uptake, regional uptake and diffuse uptake). In DCM patients, 5 had faint uptake, 7 had regional uptake, and the other 2 had diffuse uptake. On the other hand, all ICM patient had regional uptake (p < 0.05). In DCM, there were no significant relationships between the patterns and LV functions. On the other hand, there were close correlation between the H/L ratio after glucose loading and the left ventricular ejection fraction (r = 0.680, p < 0.01). The changes in PET images caused by glucose loading were classified into 2 types (non-reversing and reversing patterns). DCM significantly showed a non-reversing pattern (86%, 12 of 14 patients) whereas ICM showed mainly a reversing pattern (70%, 7 of 10 patients; p < 0.05). In conclusion, myocardial FDG uptake after glucose loading may indicate a myocardial viable mass although FDG uptake at fasting was not evidently related to LV function. The change in the pattern of the FDG image from fasting to glucose loading may be useful in differentiating DCM from ICM.

Myocardial metabolic and receptor imaging in idiopathic dilated cardiomyopathy

“…Yamaguchi et al [73] investigated regional myocardial 18 F-FDG distribution with injection during fasting and following glucose loading in patients with heart failure due to IDC or postischemic LV dysfunction. In 7/14 IDC patients and 10/10 ischemic patients, regional FDG uptake was seen with fasting.…”

Myocardial positron emission computed tomographic images obtained with fluorine-18 fluoro-2-deoxyglucose predict the response of idiopathic dilated cardiomyopathy patients to beta-blockers

“…By contrast, there have been only a few FDG-PET studies in idiopathic dilated cardiomyopathy (DCM). Some of them have shown that FDG-PET is useful in differentiating between idiopathic DCM and ischemic cardiomyopathy (5) and that inhomogeneous glucose metabolism predicts a poor outcome in DCM (6).…”

The impact of left ventricular reconstruction on survival in patients with ischemic cardiomyopathy

“…Left ventricular dilatation following myocardial infarction is a harbinger of the development of heart failure and left ventricular endsystolic volume index is a strong predictor or mortality. Patients with LVEF <30% and left ventricular end-systolic volume index >100 ml/m 2 have a 5-year survival of 54% [7]. Furthermore, increased preoperative left ventricular size predicts a poor outcome following CABG patients with preoperative ejection fractions <30% and a left ventricular end-systolic volume index >100 ml/m 2 have a 5-year survival of only 54% [8].…”

“…Randomized testing is underway in the STICH trial, and the Cleveland Clinic re-establishes its vital importance by mirroring their 1978 report regarding the VA Hospital CABG trial [7]. The prior question investigated if a closed artery should be opened, whereas this article tests a comparable biologic principle by surveying mechanical changing of a diseased sphere into conical form with restoration.…”