---
title: Aortic dissection
description: What aortic dissection is, why it develops, how it is recognised, which treatment approaches clinical guidelines describe and when to call an ambulance.
type: disease
aliases:
  - AD
  - acute aortic dissection
sources:
  - tier: guideline
    org: esc
    title: 2024 ESC Guidelines for the management of peripheral arterial and aortic diseases
    year: 2024
    doi: 10.1093/eurheartj/ehae179
    url: https://doi.org/10.1093/eurheartj/ehae179
  - tier: guideline
    org: aha-acc
    title: '2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines'
    year: 2022
    doi: 10.1161/CIR.0000000000001106
    url: https://doi.org/10.1161/CIR.0000000000001106
  - tier: guideline
    org: minzdrav-rf
    title: Расслоение аорты
    year: 2025
    url: https://cr.minzdrav.gov.ru/view-cr/946_1
  - tier: reference
    org: msd-manuals
    title: Aortic Dissection (MSD Manual Professional Version)
    year: 2024
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/diseases-of-the-aorta-and-its-branches/aortic-dissection
sources_checked: 2026-10-12
review: null
---

Aortic dissection (AD) is a breakdown of the middle layer of the aortic wall: blood gets inside the wall, the layers of the wall separate, and two channels (lumens) form in the <Structure id="aorta">aorta</Structure>.<Cite n={3} /> Dissection belongs to the acute aortic syndromes, life-threatening conditions in which the integrity of the aortic wall is breached, and it is the most common of them.<Cite n={[2, 3]} /> The acute aortic syndromes also include [intramural haematoma and penetrating atherosclerotic ulcer](../intramural-hematoma/).<Cite n={[2, 3]} /> Untreated dissection of the ascending aorta is highly lethal: early mortality reaches 1–2% per hour after symptoms begin.<Cite n={2} />

<Diagram name="aortic-dissection">
  <p slot="normal">The aortic wall has an inner layer (intima), a middle layer (media) and an outer layer (adventitia). Normally the intima is intact, and blood from the heart flows through a single lumen of the aorta.<Cite n={[2, 3]} /></p>
  <p slot="disease">In dissection a tear appears in the intima, and blood passes through it into the media. The detached flap of intima divides the aorta into the true lumen, where blood flows forward, and a newly formed false lumen within the wall.<Cite n={[2, 3]} /></p>
</Diagram>

## Why it happens

<Patient>

Most often it starts with a tear in the inner layer of the aortic wall: blood passes through it into the middle layer and splits the wall apart.<Cite n={[2, 3]} /> A new, false channel for blood forms inside the wall.<Cite n={[2, 4]} /> If the blood also breaks through the outer layers, the aorta ruptures.<Cite n={[2, 3]} />

The underlying cause is weakness of the middle layer of the aortic wall.<Cite n={3} /> The most common risk factor is high blood pressure.<Cite n={[3, 4]} /> The risk is also raised by diseases of the aorta or the <Structure id="aortic-valve">aortic valve</Structure>, aortic disease in the family, previous heart surgery, smoking, blunt chest injuries and illicit drug use.<Cite n={3} /> Men are affected more often, and dissection becomes more common with age.<Cite n={3} />

</Patient>

<Student>

In most cases AD is caused by an intimal tear: blood passes into the media and splits the intima longitudinally, creating a dissection flap that divides the true lumen from a newly formed false lumen.<Cite n={[2, 3]} /> The Russian Ministry of Health guideline defines the true lumen as the lumen with antegrade flow, and the false lumen as the lumen with retrograde flow or thrombosis.<Cite n={3} /> Blood in the false lumen may return to the true lumen through a second intimal tear (re-entry tear); if it instead tears through the outer media and adventitia, aortic rupture results.<Cite n={[2, 3]} />

Hypertension is present in 65–75% of patients with AD.<Cite n={3} /> Most dissections occur between the ages of 50 and 70 years, but patients with Marfan syndrome, bicuspid aortic valve, Loeys–Dietz syndrome and vascular Ehlers–Danlos syndrome present at younger ages.<Cite n={2} />

In the Stanford classification, type A involves the ascending aorta irrespective of the site of the primary intimal tear, and type B does not involve the ascending aorta (including dissections that involve the arch).<Cite n={[2, 3]} /> In the DeBakey classification, type I originates in the ascending aorta and extends at least to the arch, type II is confined to the ascending aorta, and type III originates in the descending thoracic aorta and extends distally.<Cite n={[2, 3]} /> By time from symptom onset, AD is classified as acute (less than 14 days), subacute (15–90 days) and chronic (more than 90 days).<Cite n={3} />

</Student>

<HeartModel highlight={['aorta']} />

## Symptoms

<Patient>

The main symptom is sudden, severe pain in the chest and/or back, sometimes in the abdomen.<Cite n={[2, 3]} /> The pain is worst at the very start.<Cite n={2} /> It is described as "tearing", but people more often call it sharp or stabbing; the most typical feature is how suddenly it begins.<Cite n={[2, 3]} /> The pain may move as the dissection spreads along the aorta.<Cite n={4} />

Fainting can happen.<Cite n={3} /> If the dissection blocks blood flow in the arteries that branch off the aorta, organs do not get enough blood: the brain and spinal cord, the heart, the bowel, the kidneys, the arms and the legs.<Cite n={3} /> This is why signs of a stroke or paralysis of the legs may appear.<Cite n={2} />

</Patient>

<Student>

The most common pain location is the chest (80%); back and abdominal pain occur in 40% and 25% of cases respectively.<Cite n={3} /> Aortic dissection must be considered in any patient with chest pain, thoracic back pain, unexplained syncope, unexplained abdominal pain, stroke or acute-onset heart failure, especially when pulses or blood pressures in the limbs are unequal.<Cite n={4} />

Syncope is an important presenting symptom: it occurs in about 15% of patients with type A and 5% with type B and is associated with higher in-hospital mortality, because it often accompanies cardiac tamponade or dissection of the arch vessels.<Cite n={3} /> A pulse deficit is found in 30% of patients with type A and 15% with type B; when the dissection extends into the arch vessels, blood pressure may differ between the right and left arms.<Cite n={3} />

Life-threatening complications include acute aortic regurgitation, myocardial ischaemia, cardiac tamponade, stroke and malperfusion syndromes.<Cite n={2} /> Tamponade occurs in 20% of patients with acute type A dissection and doubles mortality.<Cite n={3} />

</Student>

## How it is diagnosed

<Patient>

The doctor asks about the pain, examines the patient and measures blood pressure in both arms and both legs: a difference may point to dissection.<Cite n={[2, 3]} /> The diagnosis is confirmed by a CT scan of the aorta with contrast dye (CT angiography): a fast and accurate test that is available in many hospitals.<Cite n={[1, 2, 3]} /> An ultrasound of the heart (echocardiography) is also done, but on its own it is not enough for the diagnosis.<Cite n={[1, 3]} /> An ECG is recorded, but it does not show the dissection itself.<Cite n={[3, 4]} />

</Patient>

<Student>

The ESC recommends assessing the likelihood of acute aortic syndrome with a multiparametric algorithm using the ADD-RS (aortic dissection detection risk score).<Cite n={1} />

The first-line imaging technique is ECG-gated CT angiography from the neck to the pelvis: it is widely available and accurate, and shows the entry tear, the extent of the dissection and complications.<Cite n={1} /> Focused transthoracic echocardiography is part of the initial evaluation but cannot be the only imaging method.<Cite n={[1, 3]} /> Transoesophageal echocardiography (TOE) and MR angiography are alternatives for initial imaging; for unstable patients who cannot be transferred to CT, the ESC recommends TOE.<Cite n={[1, 2, 3]} /> Findings of an intimal flap and a double lumen on imaging confirm the diagnosis.<Cite n={4} />

A plain chest X-ray is neither sufficiently sensitive nor specific to be diagnostic.<Cite n={2} /> In AD the ECG ranges from normal to markedly abnormal, so it is not diagnostically helpful for the dissection itself.<Cite n={4} />

</Student>

## How it is treated

<Patient>

Treatment starts at once, in an intensive care unit: pain is relieved, and medicines are given that lower the pulse rate and blood pressure and so reduce the stress on the aortic wall.<Cite n={[2, 3]} />

Type A dissection, which involves the ascending aorta, needs urgent surgery.<Cite n={[1, 2]} /> During the operation the surgeon sews a synthetic graft into the aorta.<Cite n={[3, 4]} />

Type B dissection without complications is first treated with medicines: pain relief and blood pressure control.<Cite n={[1, 2, 3]} /> If complications develop, such as rupture of the aorta or poor blood supply to organs, an urgent procedure is needed.<Cite n={[1, 2, 3]} /> This is usually endovascular repair: a special graft (stent graft) is placed inside the aorta through a cut in the groin.<Cite n={[1, 3]} /> If this approach is not suitable, open surgery is done.<Cite n={3} />

After the acute phase, medicines that lower blood pressure and pulse rate are taken for a long time; according to the Russian Ministry of Health guideline, for life.<Cite n={[2, 3]} /> The aorta is checked regularly with scans (CT or MRI) both after surgery and when only medicines are used; after surgery, for life.<Cite n={[2, 4]} /> First-degree relatives (parents, brothers, sisters and children) are advised to have their aorta checked.<Cite n={2} /> The doctor decides which treatment is needed.

</Patient>

<Student>

Initial management of acute aortic syndrome is pain relief and anti-impulse therapy in an intensive care unit with invasive blood pressure monitoring to decrease aortic wall stress; it includes intravenous beta-blockers unless contraindicated.<Cite n={[2, 3]} />

In acute type A dissection, emergency surgical consultation and evaluation and immediate surgical intervention are recommended.<Cite n={[1, 2]} /> The goal of surgery is to obliterate entry into the false lumen and reconstitute the aorta with a synthetic graft.<Cite n={4} />

In uncomplicated acute type B dissection, medical therapy with pain relief and blood pressure control is the initial strategy.<Cite n={[1, 2, 3]} /> In complicated acute type B dissection (rupture, malperfusion), emergency intervention is recommended; the ESC names TEVAR (thoracic endovascular aortic repair) as first-line therapy.<Cite n={[1, 2, 3]} /> If the anatomy is not suitable for TEVAR, the Russian Ministry of Health guideline recommends open surgical repair.<Cite n={3} />

In the long term, beta-blockers are recommended to control heart rate and blood pressure (lifelong, according to the Russian Ministry of Health guideline); the ESC recommends antihypertensive therapy in all patients with chronic type B dissection.<Cite n={[1, 2, 3]} /> Aortic imaging (CT or MRI) is recommended both after surgery and after medical therapy alone; after surgical repair the aorta is monitored for life, because redissection, localised aneurysms of the weakened aorta and progressive aortic regurgitation can develop.<Cite n={[2, 4]} /> Screening of first-degree relatives with aortic imaging is recommended.<Cite n={2} />

</Student>

## When to call an ambulance

Acute aortic dissection requires emergency hospital admission.<Cite n={3} /> Call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) for sudden, severe pain in the chest or back (sometimes in the abdomen), especially if it is worst at the very start.<Cite n={[2, 3]} /> The pain is not necessarily "tearing": more often it is described as sharp or stabbing.<Cite n={2} /> Also call an ambulance for fainting, signs of a stroke or sudden paralysis of the legs.<Cite n={[2, 3]} /> As with any heart condition, call an ambulance for fainting, chest pain or severe shortness of breath: this is the site's general safety rule, repeated at the bottom of every page.

<Quiz />