Bradycardia and Sleep Apnea: What You Need to Know

Sleep apnea is a disorder that can increase the risk of serious health complications. As well as increasing the risk of stroke and diabetes, sleep apnea left untreated can have a detrimental effect on heart health. One heart condition that this sleep disorder can impact is bradycardia.

What Is Bradycardia?

Bradycardia is a condition where you have a lower heart rate than average. A resting heart rate is normally between 60 to 100 beats a minute. With bradycardia, your heartbeat will be below 60 beats per minute.

Such a low heart rate can lead to health issues if the heart struggles to pump enough blood and oxygen around the body. Your physician will recommend tests if they feel you may have this heart condition.

Diagnosis of bradycardia

Your healthcare provider will carry out a physical test first, including checking your heart rate. The condition has several possible causes, including inflammation around the heart, infection, an underactive thyroid, and an electrolyte deficiency. Therefore, blood tests will be done to check for underlying causes of your irregular heart rate.

An Electrocardiogram (ECG) is the primary test used to check for a low heart rate. The ECG will show the rate of your heartbeat at that moment in time. It uses sensors to accurately measure electrical activity within the heart.

If an ECG is unable to detect a slow heartbeat at the time of the test, you may be given a portable ECG to use. These could either measure your heart’s activity over a period of 24 hours or more -- or be switched on when you feel the symptoms such as feeling faint, chest pains, and dizziness associated with the condition.

Another possible cause of your low heart rate is sleep apnea.

How Sleep Apnea Affects Heart Health

Sleep apnea is a disorder that affects the quality of your sleep. The most common form is obstructive sleep apnea (OSA), where a blockage in the upper airways leads to temporary breathing pauses while you sleep.

The brain responds to the drop in blood oxygen levels by prompting the body to wake for air. These arousals can happen many times every hour, with the resulting daytime fatigue, one of the disorder’s primary symptoms.

OSA increases the risk of coronary artery disease. This is when the blood vessels narrow, and can cause heart attacks and heart disease. In one study,70% of those admitted to the hospital with coronary artery disease also had OSA.

The oxygen deprivation from OSA is seen as a reason why the disorder can have such a devastating impact on heart health. The frequent drops in blood oxygen levels can mean your heart works harder to compensate – damaging blood vessels and pushing up your blood pressure.

OSA can often remain undiagnosed. Two major symptoms, frequent brief nighttime awakenings for air and snoring, might only be noticed by a bed partner. When the disorder is severe, the additional stress can lead to an enlarged heart that does not pump blood as efficiently.

The reduced levels of oxygen resulting from OSA can also be a factor for a low heart rate. A slow heart rate could be a sign that you are not receiving enough oxygen due to disrupted sleep patterns caused by the sleep disorder.

Statistical Evidence of a Link

Understanding links between health conditions can be important, as treating one may improve the other. A systematic review analyzed 34 studies to see how often the simultaneous presence of sleep apnea and a low heart rate occurred.

It was found that for those with bradycardia, over 50% had obstructive sleep apnea. That group had a strong tendency to have bradycardia symptoms at night – which ties in with the breathing difficulties experienced overnight with OSA.

Will Treating Obstructive Sleep Apnea Help My Heart Health?

Obstructive Sleep apnea is a treatable disorder. By improving your sleep health, you can also reduce the risk of heart complications the disorder can cause. 

However, it is estimated that up to 85% of those with OSA are unaware they have the disorder. That’s why it is important to discuss your sleep problems with your doctor – especially symptoms like loud snoring every night, waking up gasping for air, feeling fatigued every day, and drowsy driving.

Therapy and Lifestyle Changes 

Continuous positive airway pressure (CPAP) therapy is a leading treatment for OSA. It involves a device that delivers pressurized air through a mask while you sleep. The air is set at a pressure derived from a sleep study. By delivering pressurized air, CPAP prevents the collapse of the upper airways and allows you to breathe without interruption through the night.

As obesity is a major contributing factor to OSA, lifestyle changes may also be recommended. This can include a more balanced diet and more exercise. Excess tissues in the throat can be pulled down to block the airways while sleeping. Losing weight can help reduce this risk factor.

Treating sleep apnea helps maintain your blood oxygen levels overnight and reduces the stress placed on your heart. Therefore, treating OSA using a plan such as CPAP therapy can also help your heart health. This may also help control an irregular heart rhythm such as a low heart rate resulting from low blood oxygen levels.

Get Tested for Sleep Apnea

Your health provider may recommend a sleep study if they suspect you have sleep apnea -- and if it may be the cause of your bradycardia. Initial testing is often done at home, with simple-to-use technology that monitors your oxygen level during sleep. 

It’s the first step in getting answers to your sleep problems – and your heart problems, too. 

Once diagnosed, obstructive sleep apnea can be treated, and by treating the underlying condition you might correct an abnormally low heart rate.