Sleeping on the left side may worsen atrial fibrillation (AFib) symptoms for some people, but more research is necessary. The best sleeping position may depend on a person’s symptoms and individual health factors.

The connection between sleeping position and AFib symptoms may come down to how different positions can influence heart pressure, vagal tone, and overall cardiovascular function.

For people with AFib, certain positions might inadvertently increase the strain on the heart or alter its electrical conduction in ways that promote symptoms.

This article explains how sleeping position may affect AFib, why symptoms may worsen while sleeping, and tips for better sleep.

A person with AFib sleeping on their side in bed.-2Share on Pinterest
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The impact of laying down and specific sleep positions on AFib involves physiological changes in the body that can influence heart function and the likelihood of experiencing AFib symptoms.

A 2021 questionnaire study suggests lying on a person’s left side can increase the likelihood of experiencing AFib symptoms for some people.

This position can exert additional pressure on the heart, potentially leading to more pronounced palpitations. The proximity of the heart to the chest wall in this position might increase awareness of these palpitations.

Some people with AFib may find sleeping on their right side more comfortable, as it may exert less pressure on the heart, potentially leading to fewer symptoms.

However, further research is necessary to understand how other sleeping positions may affect AFib symptoms, including which position minimizes symptoms.

AFib may feel worse or become more noticeable while sleeping for the following reasons.

Vagal stimulation

While asleep, the body’s parasympathetic nervous system, which promotes rest and digestion, becomes more active. This increase in parasympathetic activity, particularly vagal tone, can affect the heart’s electrical system.

Researchers associate a high vagal tone with the slowing of the heart rate. Overactivation of the parasympathetic nervous system may also trigger AFib episodes or make them more likely to occur in predisposed people.

Learn more about the vagus nerve.

Sleep apnea

Sleep apnea causes repeated interruptions in breathing during sleep, leading to fluctuations in oxygen levels and increased stress on the heart.

These episodes of low oxygen can trigger AFib, worsen its symptoms, or reduce the effectiveness of certain AFib treatments.

AFib symptoms may become more noticeable while sleeping since sleep apnea occurs during sleep.

Learn more about sleep apnea.

Lying down

When a person lies down, the distribution of blood throughout the body changes.

For some, these changes in the volume of blood returning to the heart and, therefore, the pressure against which the heart must pump blood may affect heart conditions, such as AFib.

Lying down may also lead to more pronounced symptoms due to the positional effects on the heart and the circulatory system.

Quieter environment

Sleeping environments are typically quieter, with fewer distractions than during times of wakefulness.

This may make people more aware of their heartbeat, allowing them to notice irregularities or palpitations they might not detect during the busier hours.

Psychological stress

For some people, the time of rest can be a period of increased stress or anxiety, especially if they are worried about their health or if lying in bed gives them too much time to focus on their heartbeat.

Psychological stress may increase the likelihood of AFib episodes by activating the sympathetic nervous system and increasing the heart rate.

Sleeping better with AFib may involve addressing both the direct symptoms of AFib and any underlying conditions or lifestyle factors that might exacerbate it.

The following changes may help people get better quality sleep.

  • establishing a regular sleeping schedule
  • engaging in calming activities before bed, such as:
  • avoiding stimulants in the hours before sleep
  • exercising regularly
  • having good sleep hygiene practices, including:
    • keeping a cool room temperature
    • having comfortable bedding
    • minimizing noise and light pollution

If a person’s AFib symptoms worsen during stressful times, taking measures to reduce stress, such as practicing mindfulness or yoga, may help them sleep better.

Some doctors may also prescribe medications to manage a person’s heart rate and rhythm, which may reduce discomfort and symptoms while sleeping.

Underlying conditions

Certain conditions, such as sleep apnea, may worsen or trigger AFib episodes. Seeking treatment for these conditions may help improve AFib symptoms.

A doctor may prescribe breathing devices, such as a continuous positive airway pressure (CPAP) machine, or lifestyle changes to treat sleep apnea.

Treating other underlying conditions may help reduce the impact of AFib on a person’s sleep, improving their sleep quality. People should work closely with healthcare professionals to tailor these tips to their health needs and circumstances.

AFib can increase the risk of other health conditions, including stroke and heart failure. People should seek treatment if they experience symptoms of AFib or if their current symptoms worsen.

AFib symptoms may include:

People who experience symptoms of stroke or heart attack must seek immediate medical attention.

Learn how to spot a heart attack.

For people with atrial fibrillation (AFib), it may be helpful to experiment with different sleeping positions to identify which one minimizes symptoms.

Addressing other underlying conditions, such as sleep apnea, and consulting healthcare professionals for personalized advice can also help improve sleep quality.

A healthcare professional may recommend specific lifestyle changes, sleep positions, or treatments to help a person manage AFib more effectively.