MCQ : Nuclear-13
A PET metabolic FDG is indicated for assessment of myocardial hibernation in:
A) A patient presenting with chest pain and normal coronaries on CT angiography.
B) A patient presenting with chest pain and severe proximal left anterior descending artery stenosis and LVEF of 67%.
C) A patient presenting with multivessel severe coronary disease, LVEF of 32% and being considered for revascularization.
D) A patient with dilated non-ischemic cardiomyopathy and an LVEF of 15%.
The correct answer is: C)
The purpose of PET FDG testing is to differentiate hibernating myocardium from scarred myocardium. FDG is useful for assessment of myocardial hibernation since it uses the pathologic shift of myocardial cell metabolism from fatty acids to glucose in ischemic situation; FDG is preferentially taken by chronically ischemic myocardium and to a much lesser extent in normal myocardium.
Patients with normal coronary arteries have no myocardium at risk. Similarly, patients with chest pain and normal LVEF have no or little scarred myocardium given the normal resting LVEF. Patients with non-ischemic cardiomyopathy might have scarred myocardium but since there is no intention to revascularize the coronary arteries, there is no indication to assess for hibernating myocardium by PET FDG.