Both hyperthyroidism and hypothyroidism can seriously affect cardiovascular health. This article discusses the mechanisms by which thyroid disease can affect the cardiovascular system, diagnostic and monitoring measures and treatment options.
- Hyperthyroidism and hypothyroidism can both lead to heart disease, and thus to increased mortality.
- Hyperthyroidism is associated with tachycardia, raised systolic blood pressure, arrhythmia and atrial fibrillation, mitral valve prolapse and cardiac failure.
- Hypothyroidism is associated with bradycardia, dyslipidaemia and ischaemic heart disease, and contributes to cardiac failure.
- Amiodarone, an important antiarrhythmic drug, can cause hyperthyroidism and hypothyroidism. Amiodarone-induced hyperthyroidism can be especially challenging to treat.
- Careful monitoring of clinical thyroid status, thyroid hormone levels and heart function will guide treatment of these conditions.
- Nonthyroidal illness can alter in vitro thyroid function tests and presents a diagnostic challenge versus thyroid disease, particularly in severe heart illness.