Pet scan said for sarcoidosis: on fdg images, there is diffuse fdg uptake throughout the left ventricle wall including the septum. what does that mean?

Ask your doc...: FDG-enhanced PET/CT is to show the unusual increase or decrease in glucose metabolism at certain areas of the body especially inside a mass - before or after drug treatment. Based on the features and distribution of FDG imaging enhancement as defined from experience, a diagnosis can be drawn; of course, biopsy is ultimate means for confirmation. So, ask doc - treating or radiologist timely.