Calcium is a vital mineral in your body. It helps build teeth and bones. It’s also essential for your organs, nerves, and muscles to function properly. Calcium even helps your blood clot in the event of an injury.

But when you have too much calcium in your body, known as hypercalcemia, it can lead to issues. One such issue is heart arrhythmia. An arrhythmia can cause your heart to beat too slowly, too quickly, or irregularly.

This article looks at how too much calcium can affect your heart and what can be done to treat it.

Your heart’s electrical system is finely controlled. Timed electrical impulses ensure that your heart beats in a steady rhythm. An interruption can cause an arrhythmia, or irregular heart rate.

Calcium, which is a mineral, is a positively charged ion, so it’s an important part of your body’s electrical system. In typical quantities, calcium helps carry electrical activity in the muscles, heart, and brain.

Too much calcium in your blood can alter this electrical activity. This condition is called hypercalcemia. It can interrupt the contractions of your heart, causing a change in your heart rate.

Tachycardia is a heart rate that is too fast. It’s diagnosed when the heart rate exceeds 100 beats per minute.

Bradycardia is a heart rate that is too slow. “Too slow” is defined differently. For example, older people may have a naturally slower heart rate than younger people, so the criteria for this type of arrhythmia is different.

Hypercalcemia is more likely to cause bradycardia. Too much calcium may cause the heart contractions to slow down, so there’s more time between each heartbeat.

Many people can have hypercalcemia and never know it. It often doesn’t cause symptoms, or symptoms may not seem out of the ordinary.

Hypercalcemia is most often diagnosed during a routine blood test.


Symptoms of an arrhythmia can include:

Talk with a doctor if you have symptoms of an arrhythmia. They can order tests to determine the underlying cause.

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If a blood test reveals high calcium levels, a doctor will likely order further tests to determine the underlying cause. In 90% of cases, one of two conditions cause hypercalcemia:

  • Primary hyperparathyroidism: This condition can happen when the parathyroid glands release too much parathyroid hormone, which helps control the calcium level in the blood.
  • Cancer: Hypercalemia is a common complication of cancer.

Treatment for an arrhythmia caused by hypercalcemia depends on how severe the condition is and the underlying cause.

If the high levels of calcium are causing significant issues, treatment may include:

  • Intravenous (IV) fluids: This can help lower calcium levels in your blood.
  • Loop diuretic medications: Diuretic medications can manage fluid levels in your body. They can help your kidneys get rid of the excess calcium. This treatment may be used for people with heart failure related to hypercalcemia.
  • Hemodialysis: Hemodialysis treatment circulates your blood through filters to clean it. This treatment is used in people who have kidneys that don’t function properly or people with heart failure.
  • Bisphosphonate medication: This may include drugs such as etidronate, pamidronate, or alendronate.
  • Surgery: A surgeon can remove one or more parathyroid glands.

If cancer is causing hypercalcemia, treating the cancer will likely also help reduce calcium levels.

Besides an arrhythmia, hypercalcemia may lead to other complications, such as:

In rare instances, hypercalcemia can be life threatening. Too much calcium can damage the kidneys.

If the kidneys don’t function properly, they won’t be able to filter blood and eliminate waste products from your body through urine. If waste products build up in your body, it can cause serious complications.

Hypercalcemia occurs when you have too much calcium in your blood. It’s typically diagnosed during a routine blood test.

Hypercalcemia can cause complications if it’s not diagnosed and treated. One such issue is an arrhythmia, or an irregular heart rate. Symptoms of arrhythmia can include shortness of breath, dizziness, fatigue, and chest pain.

Treatment for an arrhythmia caused by hypercalcemia aims to restore regular heart rhythm and improve overall heart function.