Symptoms of atrial fibrillation, like shortness of breath, night sweats, and heart palpitations, can make it hard to fall and stay asleep.

Atrial fibrillation (AFib) occurs when the heart’s upper chambers (atria) no longer beat steadily in coordination with the lower chambers (ventricles).

In addition to causing feelings of a racing or irregular heartbeat, AFib can manifest with symptoms that may develop or worsen at night.

Changing your sleeping position may help with some symptoms, but you may need medical assistance for others.

The occurrence and frequency of AFib symptoms can be unpredictable. In some cases, you may feel your symptoms get worse or recur at night.

For example, sleep disorders like obstructive sleep apnea (OSA) may trigger or intensify AFib symptoms at night. Your sleeping position could also affect the heart’s pumping action, possibly contributing to AFib symptoms.

Anxiety is yet another reason AFib symptoms may intensify at specific times of the day or night.

AFib symptoms may come and go, often without any warning or a clear cause.

Read more about atrial fibrillation.

AFib doesn’t have specific symptoms that appear only at night. You could experience the same symptoms at any time. What may change is the frequency or your awareness of these symptoms.

Some AFib symptoms that may become more evident at night include:

  • chest discomfort, such as a thumping sensation or a pounding heartbeat
  • anxiety when you awaken
  • heavy or labored breathing throughout the night or when you wake up
  • sweating

Read about the types of atrial fibrillation.

Other common AFib symptoms, which you may experience during the day or night, include:

  • dizziness or lightheadedness
  • fainting
  • fatigue, especially with exercise or even minor exertion
  • fluttering sensation in the chest
  • irregular or racing heartbeat
  • shortness of breath
  • weakness

Having AFib increases your risk of cardiac-related incidents and stroke, according to the American Heart Association. If you experience unusual symptoms or sudden chest pain or pressure, seek emergency medical care.

Read more about the symptoms of chronic atrial fibrillation.

Sleep disturbances like OSA, sleep paralysis, and insomnia could trigger or intensify symptoms of AFib for some people.

A 2021 study noted a strong association between AFib and OSA. Sleep apnea may interfere with your heart function, increasing the chance of AFib episodes.

Similarly, a 2023 study in younger adults (average age 28) found that insomnia is associated with a 32% greater risk of developing AFib.

A separate 2024 study in people with paroxysmal AFib (meaning symptoms come and go) indicated that one night of insufficient sleep could significantly raise the risk of an AFib episode the following day.

The nature of the relationship between sleep disorders and AFib isn’t entirely understood yet. More research is needed.

Read more about the link between sleep apnea and AFib.

It’s possible that persistent AFib episodes at night lead to sleep disturbances. AFib’s nighttime symptoms can make it difficult to fall and stay asleep — the definition of insomnia.

A 2018 study suggested that AFib may contribute to insomnia and sleep disruptions throughout the night, even if you don’t have an existing sleep disorder like OSA.

The discomfort of nighttime AFib symptoms isn’t always the direct cause. AFib can affect your physical and mental health, which can also affect the quality of your sleep.

Read more about triggers for AFib.

To get a better night’s sleep if you have AFib, consider some of the following tips:

  • Practice deep breathing exercises before going to bed.
  • Change your sleeping position to determine if there’s one in which your AFib symptoms decrease.
  • Move gently every day by walking, light stretching, or weightlifting, according to a doctor’s recommendations.
  • Limit caffeine and alcohol consumption during the day, and particularly in the hours before bedtime.
  • Engage in meditation daily, especially if your stress levels increase.
  • Try grounding exercises, like splashing cold water on your face, before going to bed.
  • Follow a doctor’s recommendations if you have sleep apnea or other sleep disturbances.

Read more about management options for AFib.

Why is atrial fibrillation worse at night?

When lying quietly in bed and trying to rest, you may become more aware of an irregular heart rhythm and other symptoms easily ignored during the day. If you have sleep disorders, these may also intensify AFib symptoms.

What sleeping position is best for AFib?

Every body is different, but you can try sleeping on your right side. This may allow your heart to relax more than sleeping on your left side, which may pull on your atria and trigger AFib symptoms.

Can anxiety trigger atrial fibrillation at night?

Anxiety is an established trigger for AFib episodes. Relaxation strategies in the evening (and throughout the day) may help you manage AFib symptoms.

If you have an anxiety disorder, a mental health practitioner can address the condition directly, decreasing the chance that it may affect AFib.

AFib symptoms may intensify at night for some people with sleep disturbances or nighttime anxiety. You might also become more aware of your symptoms at night than during the day.

If you have sleep disorders, anxiety, or other conditions that may affect AFib, try to address these underlying causes with the support of a healthcare professional.