Thyroid disease can worsen cardiac symptoms in people with heart disease and accelerate underlying cardiac problems.
It can even produce new heart problems in people with otherwise healthy hearts.
This article explains what the thyroid gland does and how it affects the heart.
Verywell / Emily Roberts
It also covers the difference in symptoms and treatment between an underactive and an overactive thyroid.
Verywell / Emily Roberts
What Is the Thyroid Gland?
When there is not enough thyroid hormone, neither the heart nor the blood vessels can function normally.
The reduced level of thyroid hormone causes the heart muscle to pump less vigorously and eventually become weak.
In addition, the heart muscle cannot fully relax after each heartbeat.
Hypothyroidism also causes blood vessels to stiffen, which can lead tohigh blood pressure (hypertension).
This is particularly important if you already have heart disease.
Taken once a day, this replacement hormone mimics thyroxine, the hormone that the thyroid gland produces naturally.
Hypothyroidism is a lifelong condition.
If you are prescribed thyroid medication, expect to stay on it for life.
What’s the Connection Between Hypothyroidism and Anxiety?
Anxiety and hypothyroidism commonly occur together in the same person.
How Does Hyperthyroidism Affect the Heart?
When there is too much thyroid hormone, the heart muscle must work harder.
For a person with heart disease, having an overactive thyroid can take a big physical toll.
It also increases the heart rate.
As a result, the work of the heart is greatly increased.
Hyperthyroidism may be present without producing the classic textbook symptoms.
So if you have cardiac symptoms that cannot otherwise be readily explained, have your thyroid function measured.
The sooner, the better.
Cardiac symptoms can occur in anybody with hyperthyroidism but can be particularly dangerous in people with underlying heart disease.
It’s important to remember that these treatments are not a cure.
So is a radioactive iodine treatment to slow the production of thyroid hormones.
What’s the Connection Between Hyperthyroidism and Anxiety?
Anxiety symptoms are common among people with hyperthyroidism.
The two conditions often co-occur or mimic one another.
Who Is at Risk for Thyroid Problems?
The diagnostic process may involve a combination of blood tests, heart monitoring, and imaging tests.
Measuring the level of these substances via blood testing can help your provider understand how damaged your heart is.
These echoes can tell your provider how well your heart muscles and valves are working.
Heart issues top the list.
Managing thyroid disease can have far more benefit than just reducing symptoms like fatigue.
That includes reducing your risk of some of these concerns.
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