Thyroid disorders are one of the most commonly encountered endocrine disorders among the adult population. These disorders occur due to either the excessive or insufficient production of thyroid hormones by the thyroid gland.

The thyroid gland is responsible for the production of two main hormones, thyroxine (T4) and triiodothyronine (T3), which regulate the body’s metabolism, growth, and development, and are vital for maintaining overall health and wellbeing.

Cardiovascular disease, on the other hand, is the leading cause of death globally, accounting for 17.9 million deaths annually.

It is defined as a group of disorders that affect the heart and blood vessels, leading to various health complications such as heart attacks, strokes, coronary artery disease, and arrhythmias. There is increasing evidence that links thyroid disorders with cardiovascular disease, although the relationship between the two is complex and not yet fully understood.

This article aims to shed light on the complex relationship between thyroid disorders and cardiovascular disease.

Thyroid Disorders and Cardiovascular Disease

Thyroid hormones play a significant role in regulating the body’s cardiovascular system. For instance, they influence heart rate, the contractility of the heart, and overall blood flow and volume.

Thyroid hormones, specifically T3, act as positive inotropes, which means they increase the force of the heart’s contractions. They also cause blood vessels to dilate, leading to increased blood flow and overall cardiovascular output.

When there is an imbalance of thyroid hormones in the body, it can lead to various cardiovascular complications. There are two main types of thyroid disorders: hypothyroidism and hyperthyroidism.

Hypothyroidism and Cardiovascular Disease

Hypothyroidism is a condition where there is an insufficient production of thyroid hormones by the thyroid gland. It can lead to various cardiovascular complications such as:.

Bradycardia: A slow heart rate, often less than 60 beats per minute, which can cause lightheadedness, fatigue, and fainting.
Increased blood pressure: Hypothyroidism can cause an increase in blood pressure, which can lead to various health complications such as heart attacks, strokes, and kidney damage.
Elevated cholesterol levels: Hypothyroidism can increase the levels of LDL cholesterol, also known as “bad” cholesterol, which can lead to the formation of plaques in the arteries, resulting in atherosclerosis and various cardiovascular complications.
Pericardial effusion: A buildup of fluid around the heart, which can lead to chest pain and difficulty breathing.

Hyperthyroidism and Cardiovascular Disease

Hyperthyroidism is a condition where there is an excessive production of thyroid hormones by the thyroid gland. It can lead to various cardiovascular complications such as:.

Tachycardia: A fast heart rate, often more than 100 beats per minute, which can cause palpitations, anxiety, and chest pain.
Arrhythmias: Hyperthyroidism can lead to various arrhythmias, including atrial fibrillation, ventricular tachycardia, and others.
Decreased blood pressure: Hyperthyroidism can cause a decrease in blood pressure, which can lead to dizziness, fainting, and other associated complications.

Subclinical Hypothyroidism and Cardiovascular Disease

Subclinical hypothyroidism is a condition where the thyroid-stimulating hormone (TSH) levels are elevated, but the thyroid hormone levels are normal.

This condition is more prevalent among the elderly population and has been associated with various cardiovascular complications such as:.

Increased risk of heart disease: Subclinical hypothyroidism has been linked with an increased risk of coronary heart disease, cardiovascular disease, and mortality.
Dyslipidemia: Subclinical hypothyroidism has been associated with an increased risk of dyslipidemia, including high levels of LDL cholesterol and triglycerides.

Conclusion

Thyroid disorders and cardiovascular disease have a complex relationship, with various cardiovascular complications associated with both hypothyroidism and hyperthyroidism.

It is, therefore, important to be aware of the potential cardiovascular risks associated with thyroid disorders and their management. Patients with suspected thyroid disorders should undergo a thorough evaluation, including a complete cardiovascular assessment, to ensure early diagnosis and appropriate management.