Plasma Volume Is Normal but Heterogeneously Distributed, and True Anemia Is Highly Prevalent in Patients With Stable Heart Failure.

BACKGROUND: Intravascular volume overload and depletion as well as anemia are associated with increased hospital admissions and mortality in patients with heart failure. This study aimed to accurately measure plasma volume and red cell mass (RCM) in stable patients with chronic heart failure with reduced ejection fraction (HFrEF) and gain more insight into plasma volume regulation and anemia in stable conditions of HFrEF. METHODS AND RESULTS: Plasma volume and RCM measurement based on 99Tc-labeled red blood cells, venous blood sample,s and clinical parameters were obtained in 24 stable HFrEF patients under optimal medical therapy. Measured plasma volume values were compared with predicted values based on body surface area. Plasma volume was on average normal (99.98% of predicted) but heterogeneously distributed (variations of 81%-133%). Neurohumoral activation and medication use were not associated with plasma volume status. Furthermore, anemia based on actual measurement of RCM was present in up to 75% of subjects, but rarely hemodilutional. CONCLUSIONS: In stable chronic HFrEF patients under optimal medical therapy, plasma volume is overall normal but heterogeneously distributed. Anticipated factors such as neurohumoral activation and heart failure medication were not associated with plasma volume. Furthermore, anemia is more common than as assessed by hemoglobin.

Riedel's thyroiditis and retroperitoneal fibrosis in multifocal fibrosclerosis: positron emission tomographic findings.

PURPOSE: The authors describe F-18 fluorodeoxyglucose positron emission tomographic (FDG PET) imaging features of Riedel's thyroiditis and retroperitoneal fibrosis in a patient with multifocal fibrosclerosis. MATERIALS AND METHODS: A 41-year-old woman in whom Riedel's thyroiditis had been diagnosed 7 months earlier was examined for fatigue, anorexia, and lower back pain, irradiating to the abdomen. Abdominal sonography and computed tomography showed a retroperitoneal mass. A biopsy of this mass showed histopathologic findings of retroperitoneal fibrosis. FDG PET was performed to evaluate the activity of the retroperitoneal fibrosis and to screen for other areas of fibrosclerosis. RESULTS: The FDG-PET images showed an intense hypermetabolic abdominal mass surrounding the aorta and increased glucose metabolism in the thyroid. No other sites of abnormal FDG metabolism were noted. These abnormalities disappeared after 4 months of steroid therapy. CONCLUSIONS: Sites of multifocal fibrosclerosis can be demonstrated by FDG PET, probably as a result of active inflammation involving lymphocytes, plasma cells, and fibroblast proliferation. FDG PET can help to establish the diagnosis of multifocal fibrosclerosis and evaluate the activity and patient response to corticosteroid therapy.