How Does Thyroid Disease Affect the Heart?

0
291

Disease of the thyroid gland often produces heart problems. In fact, one of the most important reasons to diagnose and treat thyroid disease is to prevent the cardiac conditions that can result from it.

Overview

The thyroid gland is a small gland located in the neck just below the Adam’s apple, and is responsible for regulating many vital bodily functions. By producing just the right amount of thyroid hormone, the thyroid helps to regulate your body’s metabolism — most importantly, how much oxygen and energy your body uses — as well as your digestive function, muscle function, and skin tone.

In fact, the thyroid has at least some effect on every organ in the body, including the heart.

In a person who has almost any type of heart disease, disorders of the thyroid gland can worsen cardiac symptoms or cause new ones, and can accelerate the underlying cardiac problem. Thyroid disease can even produce brand new heart problems in people with otherwise healthy hearts.

Thyroid disease affects the heart either by producing too little thyroid hormone (a condition called hypothyroidism) or too much thyroid hormone (called hyperthyroidism). Both types of thyroid disorders are common and both can have a significant effect on the heart.

Hypothyroidism

Thyroid hormone is very important for normal cardiovascular function. When there is not enough thyroid hormone, neither the heart nor the blood vessels can function normally.

In hypothyroidism, the reduced level of thyroid hormone causes the heart muscle to pump less vigorously and eventually to become weakened.

In addition, the heart muscle cannot fully relax after each heart beat.

This failure to relax can produce diastolic dysfunction, a condition that can lead to heart failure. Hypothyroidism also causes blood vessels to stiffen, which can produce hypertension.

Cardiac symptoms can occur in anybody with hypothyroidism, but they are especially likely in people who already have underlying heart disease.

Common cardiac problems associated with hypothyroidism include:

  • Dyspnea —Shortness of breath on exertion and poor exercise tolerance in hypothyroidism is usually due to weakness in the skeletal muscles. In people who also have heart disease, it may be due to worsening heart failure.
  • Slow heart rate (bradycardia)—The heart rate is modulated by thyroid hormone. So, with hypothyroidism, the heart rate is typically 10 to 20 beats per minute slower than normal. Especially in patients who also have heart disease, however, hypothyroidism may worsen the tendency for premature beats (such as PVCs ) and may cause atrial fibrillation.
  • Diastolic hypertension —One might think that, because a lack of thyroid hormone slows down the metabolism, people with hypothyroidism might experience low blood pressure. Usually, the opposite is true—the arteries are stiffer in hypothyroidism, which causes the diastolic blood pressure to rise.
    • Worsening of heart failure or new onset of heart failure—Hypothyroidism can make well-controlled heart failure worsen and can produce heart failure for the first time in patients with relatively mild underlying heart disease.
    • Edema (swelling)—Edema can occur as a result of worsening heart failure. In addition, hypothyroidism itself can produce a type of edema called myxedema, caused by an accumulation of abnormal proteins and other molecules in the interstitial fluid (fluid external to the body’s cells).
    • Worsening of coronary artery disease (CAD) —While the reduction in thyroid hormone can actually make angina (chest discomfort associated with CAD) less frequent in patients who have angina, the increase in LDL cholesterol (bad cholesterol) and in C-reactive protein seen with hypothyroidism may accelerate any underlying CAD.

    Hypothyroidism is often an extremely subtle condition. It typically has a very gradual onset, so its symptoms can “sneak up” on you. Furthermore, especially in older people, hypothyroidism often occurs without the typical constellation of “textbook” symptoms that doctors usually expect.

    Also, hypothyroidism is more frequent than many doctors realize. So if you have any symptoms suggestive of hypothyroidism and your doctor does not have a ready or convincing explanation for them (especially if you already have heart disease of any type), you should ask your doctor to measure thyroid hormone levels.

    Hypothyroidism is treated with thyroid hormone medication. The adequate treatment of hypothyroidism is a bit tricky and even controversial.

    Hyperthyroidism

    Hyperthyroidism is caused by the overproduction of thyroid hormone. When there is too much thyroid hormone, the heart muscle is being ”whipped” like a horse and, for a person with heart disease it’s like whipping a tired horse.

    Excess thyroid hormone increases the force of contraction of the heart muscle and increases the amount of oxygen demanded by the heart. It also increases the heart rate. As a result, the work of the heart is greatly increased.

    Cardiac symptoms can occur in anybody with hyperthyroidism, but can be particularly dangerous in people with underlying heart disease. Common symptoms include:

    • Worsening of heart failure or new onset of heart failure—Hypothyroidism can make well-controlled heart failure worsen and can produce heart failure for the first time in patients with relatively mild underlying heart disease.
    • Edema (swelling)—Edema can occur as a result of worsening heart failure. In addition, hypothyroidism itself can produce a type of edema called myxedema, caused by an accumulation of abnormal proteins and other molecules in the interstitial fluid (fluid external to the body’s cells).
    • Worsening of coronary artery disease (CAD) —While the reduction in thyroid hormone can actually make angina (chest discomfort associated with CAD) less frequent in patients who have angina, the increase in LDL cholesterol (bad cholesterol) and in C-reactive protein seen with hypothyroidism may accelerate any underlying CAD.

    Hypothyroidism is often an extremely subtle condition. It typically has a very gradual onset, so its symptoms can “sneak up” on you. Furthermore, especially in older people, hypothyroidism often occurs without the typical constellation of “textbook” symptoms that doctors usually expect.

    Also, hypothyroidism is more frequent than many doctors realize. So if you have any symptoms suggestive of hypothyroidism and your doctor does not have a ready or convincing explanation for them (especially if you already have heart disease of any type), you should ask your doctor to measure thyroid hormone levels.

    Hypothyroidism is treated with thyroid hormone medication. The adequate treatment of hypothyroidism is a bit tricky and even controversial.

    Hyperthyroidism

    Hyperthyroidism is caused by the overproduction of thyroid hormone. When there is too much thyroid hormone, the heart muscle is being ”whipped” like a horse and, for a person with heart disease it’s like whipping a tired horse.

    Excess thyroid hormone increases the force of contraction of the heart muscle and increases the amount of oxygen demanded by the heart. It also increases the heart rate. As a result, the work of the heart is greatly increased.

    Cardiac symptoms can occur in anybody with hyperthyroidism, but can be particularly dangerous in people with underlying heart disease. Common symptoms include:

    Source:https://www.verywellhealth.com

LEAVE A REPLY

Please enter your comment!
Please enter your name here