Aortic dissection
Aortic dissection is a tear in the aortic intima allowing blood to split the media, creating a false lumen, and is a surgical emergency. Type A (ascending) dissection needs emergency surgery, while type B (descending) is usually managed medically with rapid heart-rate and blood-pressure control; the priority is impulse control with a beta-blocker first.
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What this article covers
- Overview
Definition: aortic dissection is a tear in the aortic intima that lets blood enter and split the media, creating a false lumen that propagates along the aorta.
- Epidemiology
Uncommon but highly lethal, with mortality rising each hour in untreated type A disease.
- Risk factors
Hypertension (the dominant risk factor). Aortic aneurysm and prior aortic disease or surgery.
- Pathophysiology
Intimal tear and false lumen: blood enters the media through an intimal tear, propagating a false lumen antegrade or retrograde.
- Clinical features
Sudden severe tearing or ripping chest or back pain, often migrating.
- Differential diagnosis
Acute coronary syndrome: ischemic chest pain with ST changes and a troponin rise, without a pulse deficit or a widened mediastinum, though proximal dissection can cause secondary infarction (ST-elevation myocardial infarction (STEMI)).
- Diagnosis
Establish urgently with CT angiography demonstrating the intimal flap and classify by aortic segment: the diagnostic basis is CT angiography of the aorta showing the dissection flap and false lumen…
- Management
First-line, achieve rapid impulse control with an intravenous beta-blocker to a heart rate below 60 per minute, with adequate analgesia: Esmolol: a 500 mcg/kg load then a 50 to 200 mcg/kg/min infusion.
- Complications
Aortic rupture and death. Cardiac tamponade, aortic regurgitation, and coronary compromise (type A).
- Prognosis
Type A is rapidly fatal without surgery, with hourly mortality.
- Prevention
Strict blood pressure control (target systolic below 120 mmHg in aortopathy) with a beta-blocker plus additional agents as needed.
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Related articles
- Thoracic aortic aneurysm
Thoracic aortic aneurysm is dilation of the thoracic aorta, often related to hypertension, atherosclerosis, bicuspid aortic valve, or connective tissue disease. Usually asymptomatic, it risks dissection and rupture, so management is blood pressure control, surveillance imaging, and elective repair at size thresholds that are lower in heritable aortopathy.
- Aortic regurgitation
Aortic regurgitation is diastolic backflow of blood from the aorta into the left ventricle from valve or aortic root disease. Chronic disease causes volume overload with a wide pulse pressure and a decrescendo diastolic murmur, while acute severe regurgitation is a surgical emergency; severe symptomatic or decompensating disease is treated with valve replacement.
- Marfan syndrome
Marfan syndrome is an autosomal dominant connective tissue disorder from FBN1 (fibrillin-1) mutations, with skeletal, ocular, and cardiovascular features. The cardiovascular risk drives prognosis: aortic root dilation predisposing to dissection and rupture, managed with beta-blockers or ARBs, activity restriction, surveillance imaging, and prophylactic aortic surgery.
- ST-elevation myocardial infarction (STEMI)
ST-elevation myocardial infarction is acute transmural myocardial ischemia from complete coronary occlusion, diagnosed by ischemic symptoms with diagnostic ST-segment elevation and a rising troponin. It is a time-critical emergency in which immediate reperfusion, primary PCI within 90 minutes or fibrinolysis when PCI is unavailable, plus antiplatelet and anticoagulant therapy, determines survival.
- Cardiac tamponade
Cardiac tamponade is life-threatening compression of the heart by a pericardial effusion, impairing diastolic filling and cardiac output. It presents with hypotension, distended neck veins, and pulsus paradoxus, is confirmed by echocardiography, and is treated by urgent pericardiocentesis; avoid vasodilators and aggressive diuresis.