Heart Valve Defect Common in Patients With Thyroid Disease
Nov. 30, 1999 (New York) -- A heart valve abnormality is commonly found among people with a specific type of thyroid disease, Greek researchers report in the journal Thyroid.
M.E. Evangelopoulou and colleagues from Alexandra Hospital at Athens University School of Medicine, say doctors should look for the heart valve problem, known as mitral valve prolapse or MVP, in patients with autoimmune thyroid disease. Autoimmune thyroid diseases, such as Graves' disease and Hashimoto's thyroiditis, are conditions in which the body acts against substances such as proteins produced by the thyroid gland.
MVP is a disorder in which the mitral valve does not close properly and allows blood to leak into the left atrium of the heart. MVP is found in about 5% to 15% of people under age 40 but is most common among very thin women.
Graves' disease is characterized by an enlarged thyroid gland and protrusion or bulging of the eyes. Over time, the disease can destroy the thyroid gland. Hashimoto's thyroiditis also is characterized by an enlarged thyroid and an autoimmune reaction to proteins produced in the thyroid. Both diseases occur much more frequently in women than in men.
The researchers studied 29 patients with Graves' disease, 35 patients with Hashimoto's thyroiditis, 20 patients with nonautoimmune goiter (enlarged thyroid gland), and 30 people with healthy thyroids. Cardiac ultrasound was performed in all patients to diagnose MVP and blood samples were examined for presence of substances that signal autoimmune abnormalities.
MVP was found in 28% of patients with Graves' disease, in 23% of patients with Hashimoto's thyroiditis, and in 10% with nonautoimmune goiter. MVP was not present in any members of the healthy group.
Autoimmune abnormalities in blood were found in 63% of the patients with MVP and Graves' disease and in only 14% of the patients with Graves' disease who did not have MVP. In patients with Hashimoto's disease and MVP, a high incidence of autoimmune abnormalities in blood were found 63% of the time. In patients with Hashimoto's thyroiditis who did not have MVP, autoimmune abnormalities in blood were found in only 19%.