Untreated hyperthyroidism, conditions where there is excess thyroid hormone present, can adversely affect health, leading to increased risks for abnormal heart rhythms, heart failure, osteoporosis, ...
In rare cases, hyperthyroidism may lead to congestive heart failure. This is because, in people with hyperthyroidism, the thyroid gland overproduces thyroid hormones, which can affect how the heart ...