Matters of the Heart: Images of Cardiac Disorders Myxedema Heart

Over the previous 6 months, a59-year-old man had experienced lethargy,fatigue, poor appetite, cold intolerance,and abdominal distention. Hisvital signs were normal; physical examinationrevealed periorbital andpretibial edema, distant heart sounds,and delayed reflexes.An ECG showed low voltages,and a chest film revealed generalizedenlargement of the cardiac silhouettewith a globular configuration andsmall, bilateral, pleural effusions (A).An echocardiogram confirmed thepresence of a large pericardial effusion.Subsequent laboratory studiesrevealed serum levels of thyroid-stimulatinghormone of 50 μU/mL and ofthyroxine, 4.5 μg/dL; and a reversetriiodothyronine uptake of 24.7 ng/dL.These findings are consistent withprimary hypothyroidism. Thyroidhormone replacement therapy wasinitiated. One year later, the chestfilm changes had resolved (B).The recognition of pericardial effusionsis important, because thesemay, in a short time, lead to cardiactamponade. Causes of such effusionsinclude trauma, pericarditis, renal failure,Dressler syndrome, neoplasticdisease, and immunologic disease(particularly rheumatoid arthritis andsystemic lupus erythematosus). Pericardialeffusion is a common findingin myxedema, occurring in up to onethird of all cases.