---
title: Sleep apnoea and the heart
description: What obstructive sleep apnoea is, how pauses in breathing during sleep are linked to high blood pressure, atrial fibrillation, heart failure and a slow pulse, how sleep apnoea is detected, and which treatment approaches clinical guidelines describe.
type: disease
aliases:
  - obstructive sleep apnoea
  - obstructive sleep apnea
  - sleep apnoea
  - sleep apnea
  - OSA
  - OSAHS
  - obstructive sleep apnoea/hypopnoea syndrome
  - snoring with pauses in breathing
sources:
  - tier: guideline
    org: esc
    title: 2024 ESC Guidelines for the management of atrial fibrillation
    year: 2024
    doi: 10.1093/eurheartj/ehae176
    url: https://doi.org/10.1093/eurheartj/ehae176
  - tier: guideline
    org: esc
    title: 2021 Рекомендации ESC по электрокардиостимуляции и сердечной ресинхронизирующей терапии
    year: 2022
    doi: 10.15829/1560-4071-2022-5159
    url: https://doi.org/10.15829/1560-4071-2022-5159
  - tier: guideline
    org: esc
    title: 2024 ESC Guidelines for the management of elevated blood pressure and hypertension
    year: 2024
    doi: 10.1093/eurheartj/ehae178
    url: https://doi.org/10.1093/eurheartj/ehae178
  - tier: guideline
    org: minzdrav-rf
    title: Артериальная гипертензия у взрослых
    year: 2024
    doi: 10.15829/1560-4071-2024-6117
    url: https://cr.minzdrav.gov.ru/view-cr/62_3
  - tier: guideline
    org: minzdrav-rf
    title: Фибрилляция и трепетание предсердий
    year: 2025
    doi: 10.15829/1560-4071-2025-6668
    url: https://cr.minzdrav.gov.ru/view-cr/382_2
  - tier: guideline
    org: nice
    title: 'Obstructive sleep apnoea/hypopnoea syndrome and obesity hypoventilation syndrome in over 16s (NG202)'
    year: 2021
    url: https://www.nice.org.uk/guidance/ng202
  - tier: reference
    org: msd-manuals
    title: Obstructive Sleep Apnea (OSA) (MSD Manual Professional Version)
    year: 2026
    url: https://www.msdmanuals.com/professional/pulmonary-disorders/sleep-apnea/obstructive-sleep-apnea
sources_checked: 2026-10-14
review: null
---

Obstructive sleep apnoea is a condition in which the upper airway repeatedly collapses at the level of the throat (pharynx) during sleep and breathing stops, even though the efforts to breathe continue.<Cite n={4} /> As a result, the oxygen level in the blood falls, sleep is broken up, and marked sleepiness follows during the day.<Cite n={4} /> The pauses in breathing usually end with a brief awakening.<Cite n={7} />

Sleep apnoea matters for the heart: without treatment it raises the risk of high blood pressure, arrhythmias and heart failure.<Cite n={7} /> This article is about how sleep apnoea is linked to the heart. The conditions themselves are covered in more detail in the articles on [hypertension](../hypertension/), [atrial fibrillation](../atrial-fibrillation/) and [heart failure](../heart-failure/).

<Diagram name="sleep-apnea-and-heart">
  <p slot="normal">
    The diagram shows a sleeping person in profile, the airway from the nose to the lungs, and the
    heart; the bar is a rough indicator of how much oxygen is in the blood. During sleep the muscle
    tone of the upper airway decreases.<Cite n={7} /> Normally the throat still stays open: air
    reaches the lungs and the heart beats at its usual rhythm.
  </p>
  <p slot="disease">
    In obstructive sleep apnoea the walls of the throat collapse during sleep and air stops reaching
    the lungs, although the efforts to breathe continue.<Cite n={4} /> The oxygen in the blood
    falls,<Cite n={4} /> and the pause usually ends with a brief awakening.<Cite n={7} /> During
    the pauses the pulse may slow.<Cite n={2} />
  </p>
</Diagram>

## Why it happens

<Patient>

During sleep the muscle tone of the throat decreases, and in people with sleep apnoea the throat becomes partly or completely blocked; the blood then holds less oxygen and more carbon dioxide.<Cite n={7} /> Trying to breathe in against a closed airway causes swings in pressure inside the chest that affect how the heart works.<Cite n={7} />

The risk of sleep apnoea is raised by obesity, differences in the structure of the upper airway, sleep apnoea in relatives, some conditions (for example, an underactive thyroid or a previous stroke), and alcohol or sedatives.<Cite n={7} /> Sleep apnoea becomes more common with age and in women after the menopause.<Cite n={7} /> But not everyone with sleep apnoea is overweight.<Cite n={7} />

How sleep apnoea affects the heart and blood vessels:

- In sleep apnoea, especially when it is severe, the sympathetic nervous system is activated. Blood pressure at night rises or does not fall enough, the inner lining of the blood vessels is affected, and the risk of cardiovascular complications goes up.<Cite n={4} /> People with untreated sleep apnoea and normal blood pressure are more likely to develop high blood pressure.<Cite n={7} />
- Sleep apnoea can contribute to atrial fibrillation: it raises the pressure in the atria, enlarges them or changes how the autonomic nervous system works.<Cite n={5} />
- Lack of oxygen during the pauses increases the tone of the vagus nerve, so the pulse often slows during sleep; conduction disturbances also occur.<Cite n={2} /> But a slow pulse at night also happens in people without sleep apnoea: most often it is harmless and needs no treatment.<Cite n={2} />
- Repeated lack of oxygen at night and broken sleep are linked to a higher risk of heart failure, coronary artery disease, atrial fibrillation and stroke.<Cite n={7} />

</Patient>

<Student>

Abbreviations: OSA, obstructive sleep apnoea; OSAHS, obstructive sleep apnoea/hypopnoea syndrome (the NICE term); the Russian Ministry of Health guidelines speak of obstructive sleep apnoea syndrome; RCT, randomised controlled trial; AV block, atrioventricular block. According to NICE, an apnoea is a complete pause in breathing and a hypopnoea is a reduction in breathing, each lasting 10 seconds or more, and the apnoea–hypopnoea index (AHI) is their number per hour of a multi-channel sleep study.<Cite n={6} />

OSA leads to hypoxia, hypercapnia, and endothelial and neurotransmitter dysfunction.<Cite n={7} /> Russian Ministry of Health hypertension guideline: in OSA, especially when severe, sympathetic activation leads to a rise or an insufficient fall in night-time blood pressure, endothelial dysfunction, oxidative stress and a higher risk of cardiovascular complications.<Cite n={4} /> Russian Ministry of Health AF guideline: OSA, especially combined with hypertension, diabetes and structural heart disease, may be a pathogenetic factor of AF.<Cite n={5} /> The 2024 ESC guidelines call OSA a highly prevalent condition, particularly in patients with AF, and list sleep apnoea among the factors associated with incident AF.<Cite n={1} />

2021 ESC pacing guidelines (official Russian translation): in patients with OSA, nocturnal bradycardia (sinus bradycardia and conduction disturbances) is often seen during apnoeic episodes; the key mechanism is OSA-induced hypoxaemia, which increases vagal tone.<Cite n={2} /> NICE: OSAHS is more prevalent in people with obesity, treatment-resistant hypertension, type 2 diabetes, cardiac arrhythmia (particularly AF), stroke or transient ischaemic attack, and chronic heart failure.<Cite n={6} />

</Student>

## Symptoms

<Patient>

Sleep apnoea may be suspected from loud, broken snoring and pauses in breathing during sleep, restless, unrefreshing sleep, waking often at night to pass urine, daytime sleepiness, feeling worn out and having headaches in the morning, constant tiredness, and poorer memory and concentration.<Cite n={[4, 6]} /> Some people have episodes of choking during sleep.<Cite n={6} /> Some only learn about their night-time symptoms from the people they live with.<Cite n={7} />

Snoring on its own does not mean sleep apnoea: most people who snore do not have it.<Cite n={7} /> And the other way round, not everyone with sleep apnoea feels very sleepy,<Cite n={6} /> and in some people even moderate or severe sleep apnoea causes hardly any symptoms.<Cite n={7} />

Daytime sleepiness is dangerous: untreated sleep apnoea raises the risk of injury and death in accidents when a person falls asleep at the wheel or during another hazardous activity.<Cite n={7} />

</Patient>

<Student>

Among the features that suggest OSA, the Russian Ministry of Health hypertension guideline also lists weight gain and reduced potency.<Cite n={4} /> NICE recommends assessing people for OSAHS if they have 2 or more of its typical features.<Cite n={6} />

According to MSD, the frequency of sleep complaints and the degree of wake-time sleepiness do not correlate well with the number of sleep events or arousals.<Cite n={7} />

</Student>

## How it is diagnosed

<Patient>

A doctor suspects sleep apnoea from the symptoms and risk factors, and a sleep study confirms it.<Cite n={7} /> Questionnaires, such as the Epworth Sleepiness Scale, help to judge how likely sleep apnoea is, but they are not used to make the diagnosis.<Cite n={[4, 6, 7]} />

To make the diagnosis and assess severity, breathing is recorded during sleep (respiratory or cardiorespiratory monitoring); the UK NICE guideline offers this recording at home.<Cite n={[4, 6]} /> The "gold standard" is polysomnography, a detailed recording of sleep; it is used in particular when the home recording did not show sleep apnoea but the symptoms continue.<Cite n={[4, 6]} />

People with heart conditions are checked for sleep apnoea with particular care:

- in hypertension, if there is obesity, if blood pressure is hard to control with treatment, or if 24-hour blood pressure monitoring shows that blood pressure does not fall or even rises at night;<Cite n={4} />
- in atrial fibrillation, if sleep apnoea is highly likely;<Cite n={5} />
- with a markedly slow pulse or serious conduction block during sleep, if there are signs of sleep apnoea.<Cite n={2} /> Rhythm and conduction problems are covered in the articles on [sick sinus syndrome](../sick-sinus-syndrome/) and [atrioventricular block](../av-block/).

</Patient>

<Student>

NICE: use the Epworth Sleepiness Scale in the preliminary assessment of sleepiness and consider the STOP-Bang Questionnaire as well; do not use the Epworth Sleepiness Scale alone to decide on referral, because not all people with OSAHS have excessive sleepiness.<Cite n={6} /> Severity by NICE: mild, AHI of 5 or more to less than 15; moderate, 15 or more to less than 30; severe, 30 or more per hour.<Cite n={6} />

2024 ESC AF guidelines: it may be reasonable to screen for OSA where a rhythm control strategy is pursued; polysomnography or home sleep apnoea testing is suggested in preference to questionnaires, and screening with symptom-based questionnaires only is not recommended (III B).<Cite n={1} /> Russian Ministry of Health AF guideline: in patients with AF and a high likelihood of OSA, further testing to confirm the diagnosis is recommended (ESC class IIa, level B; grade of recommendation B, level of evidence 3).<Cite n={5} /> 2024 ESC hypertension guidelines: comprehensive screening for the main causes of secondary hypertension is recommended in adults diagnosed with hypertension before the age of 40, except for obese young adults, in whom an OSA evaluation comes first (I B).<Cite n={3} /> 2021 ESC pacing guidelines: screening for OSA is recommended in patients with symptoms of OSA and severe bradycardia or high-degree AV block during sleep (I C).<Cite n={2} />

</Student>

## How it is treated

<Patient>

Everyone with sleep apnoea is advised to change their lifestyle: lose weight if they have obesity, stop smoking, drink less alcohol, and improve their sleep and free breathing through the nose; the doctor will also assess whether tranquillisers and sleeping pills are needed.<Cite n={[4, 6]} /> Losing weight reduces the severity of sleep apnoea but does not necessarily get rid of it.<Cite n={7} /> Do not stop prescribed medicines on your own: discuss them with your doctor.

The main treatment is CPAP (continuous positive airway pressure): a machine delivers air through a mask at a constant positive pressure, and this airflow stops the upper airway from collapsing.<Cite n={4} /> CPAP reduces sleepiness and snoring and improves the bed partner's sleep.<Cite n={7} /> It works while it is used: if it is stopped, the symptoms return within a few days, and it is usually continued indefinitely.<Cite n={7} /> Many people find it hard to use the machine regularly, especially those who do not feel sleepy.<Cite n={7} />

If CPAP is not suitable, the doctor may offer other options: a mouth splint, a device to avoid sleeping on the back, or surgery.<Cite n={[6, 7]} /> The doctor chooses the method together with the patient.

What treating sleep apnoea does for the heart:

- In people with high blood pressure and sleep apnoea, the Russian Ministry of Health guideline recommends CPAP to control blood pressure better.<Cite n={4} /> But blood pressure usually falls only modestly.<Cite n={7} />
- In atrial fibrillation, treating sleep apnoea is part of managing risk factors, so that episodes come back less often.<Cite n={[1, 5]} /> The evidence on the benefit of CPAP here is mixed.<Cite n={[1, 7]} />
- If the pulse slows during sleep because of confirmed sleep apnoea, the sleep apnoea is treated, with CPAP and weight loss, and a pacemaker is avoided where possible.<Cite n={2} /> If a slow pulse with symptoms also happens outside sleep, the doctor weighs the risks of the slow pulse against the benefit of a pacemaker.<Cite n={2} />

Before any operation, tell the anaesthetist that you have sleep apnoea.<Cite n={7} /> Until treatment is in place, people with marked daytime sleepiness are warned about the risks of driving and of work where falling asleep would be dangerous.<Cite n={7} />

</Patient>

<Student>

NICE: offer fixed-level CPAP, in addition to lifestyle advice, to people with moderate or severe OSAHS, and if they cannot tolerate or decline CPAP, consider a mandibular advancement splint; consider tonsillectomy for people with large obstructive tonsils and a BMI below 35 kg/m².<Cite n={6} /> According to MSD, treatment of OSA is associated with modest 2 to 3 mm Hg decreases in blood pressure, but data are mixed on the prevention of cardiovascular events and AF.<Cite n={7} />

Russian Ministry of Health hypertension guideline: CPAP is recommended to improve blood pressure control in patients with OSA (grade of recommendation A, level of evidence 1).<Cite n={4} /> 2024 ESC AF guidelines: management of OSA may be considered as part of comprehensive risk factor management to reduce AF recurrence and progression (IIb B).<Cite n={1} /> Russian Ministry of Health AF guideline: optimal treatment of obstructive sleep apnoea is recommended to reduce AF recurrences (ESC class IIa, level B; grade of recommendation B, level of evidence 3).<Cite n={5} /> According to the 2024 ESC guidelines, observational studies suggested more AF recurrence after cardioversion or ablation without CPAP, but small RCTs showed no benefit of CPAP on these outcomes, and the SAVE trial found no difference with CPAP in clinical outcomes or incident AF, although AF in that trial was not systematically screened for.<Cite n={1} />

2021 ESC pacing guidelines: if OSA is confirmed, CPAP and weight loss can be effective for sleep-related bradycardia, and pacemaker implantation should be avoided; in known or suspected OSA with symptomatic bradyarrhythmia not related to sleep, the risks of bradycardia and the benefit of a pacemaker need a comprehensive assessment.<Cite n={2} />

</Student>

## When to call an ambulance

Emergencies that sleep apnoea is linked to are described in the articles on [atrial fibrillation](../atrial-fibrillation/), [atrioventricular block](../av-block/), [sick sinus syndrome](../sick-sinus-syndrome/), [hypertensive crisis](../hypertensive-crisis/) and [heart failure](../heart-failure/): they list the signs that need urgent help.

As with any heart or blood vessel condition, call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) for fainting, chest pain or severe breathlessness: this is the site's general safety rule, repeated at the bottom of every page.