Abstract
Hypothyroidism is often found in patients with cardiovascular disease; it is a risk factor for atherosclerosis and ischaemic heart disease and has a negative impact on left and right ventricle function (hypothyroid cardiomyopathy). Overt hypothyroidism is always treated with levothyroxine replacement.
In patients with coincident cardiovascular disease, the treatment starts with a low dose of levothyroxine, which is increased gradually. In subclinically hypothyroid patients with cardiovascular disease, the levothyroxine replacement remains controversial and its benefits probably depend on the patient's age.
As the risk/benefit ratio often increases in the elderly, we are usually satisfied with target TSH in the upper part of the reference range or slightly above. With some simplification we can say that the best risk/benefit ratio of levothyroxine replacement in subclinical hypothyroidism is in cardiovascular patients aged 45-65.