Pilot Study: Hypovitaminosis D, Hyperparathyroidism and Hypomagnesemia in Patients With Congestive Heart Failure

People with heart failure may have low magnesium and low vitamin D levels. They may also have abnormally high levels of parathyroid hormones. Magnesium and vitamin D are important chemicals that are not routinely measured in blood tests. We are studying how many people with heart failure have low levels of magnesium and vitamin D. We are also studying how many people with heart failure have overactive parathyroid glands and if that is related to their vitamin D levels.