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Basic Information ⬇

Author: Vishnu Kadiyala, MD and Philip Stockwell, MD

Definition

Acute aortic syndromes are a spectrum of aortic pathologies that include aortic dissection, intramural hematomas (IMHs), and penetrating atherosclerotic ulcers.1 Aortic dissections are the most common and occur when blood passes through an intimal tear, separating the intima from the medial layers and creating a false lumen.1 IMH and penetrating aortic ulcers are variants of the classically described aortic dissection. Fig. E1 illustrates acute aortic syndromes.

Figure E1 Acute aortic syndromes.

A, Classic aortic dissection. There is a tear in the intima with blood entering the media and a dissecting cleavage plane propagating for variable distances anterograde (and occasionally retrograde) throughout the aortic wall. B, Aortic intramural hematoma (IMH). A spontaneous hemorrhage of the vasa vasorum leads to bleeding within the media in the absence of an intimal tear or intimal flap. C, Penetrating atherosclerotic aortic ulcer (PAU). An ulcerated aortic plaque ruptures into the media, leading to an outpouching or ulceration in the aortic wall. This may be associated with IMH formation; pseudoaneurysm; or a focal, thick-walled aortic dissection.

(From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.)

Classification

Aortic dissection is generally classified according to anatomic location (Fig. E2). Table E1 summarizes classification schemes of acute aortic dissection.

  • •Stanford (more commonly used classification system): Type A ascending aorta (proximal), type B descending aorta (distal).
  • •DeBakey: Type I ascending and descending aorta, type II ascending aorta, type III descending aorta.
  • •The Society of Thoracic Surgery and Society of Vascular Surgery has recently proposed a classification system of dissection subtypes to more precisely define the location of disease as extending between two anatomic zones.2
  • •Aortic dissection can also be classified by acuity of presentation: Hyperacute (<24 h), acute (2 to 7 days), subacute (8 to 30 days), and chronic (>30 days).

TABLE E1 Classification Schemes of Acute Aortic Dissection

DeBakey Classification
  • •Type I dissection originates in the ascending aorta and extends at least to the aortic arch and typically to the descending aorta (and beyond)
  • •Type II dissection only in the ascending aorta
  • •Type III dissection originates in the descending aorta, usually just distal to the left subclavian artery, and extends distally
    • •Type IIIa dissection tear limited to the descending aorta
    • •Type IIIb dissection tear extends below the diaphragm

Stanford Classification
  • •Type A dissection involves the ascending aorta (with or without extension into the descending aorta)
  • •Type B dissection does not involve the ascending aorta (includes arch dissection)

Society for Vascular Surgery/Society of Thoracic Surgeons (SVS/STS) Aortic Dissection Classification System
  • •Type A entry tear originates only in the ascending aorta (zone 0)
  • •Type B entry tear originates distal to the ascending aorta (zone 1 or beyond)

The distal extent of a type A dissection is further characterized by zone. The distal extent of a type B dissection is further characterized by two subscripts (the proximal zone of involved aorta and the distal zone of involved aorta).

From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

Figure E2 Acute aortic dissection classifications.

The Stanford classification divides dissections into those involving the ascending aorta from dissection originating there or proximal dissection of a more distal origin (Type A) or those limited to the descending aorta (Type B). The DeBakey classification divides dissections into those arising in the ascending aorta and extending distally beyond the innominate artery (Type I), arising in the ascending aorta with extension limited to the level of the innominate artery takeoff (Type II), and arising at or distal to the left subclavian artery takeoff with extension distally (Type III).

(From Walls RM et al: Rosen’s emergency medicine, concepts and clinical practice, ed 10, Philadelphia, 2023, Elsevier.)

Synonyms

  • Aortic dissection
  • Dissecting aortic aneurysm
  • AAS
    ICD-10CM CODES
    I71.00Dissection of unspecified site of aorta
    I71.01Dissection of thoracic aorta
    I71.02Dissection of abdominal aorta
    I71.03Dissection of thoracoabdominal aorta
Epidemiology & Demographics
Incidence:

2.6 to 3.5 per 100,000 person-yr; more frequent in winter as compared to other seasons, although no clear reason has been identified.3,4

Predominant Sex & Age:

Males (65%) females (35%), ages 60 to 80 yr; mean = 63 yr1,3,5

Risk Factors (Table E2):

  • •Hypertension (found in up to 77% of patients with aortic dissection)3,5
  • •Atherosclerosis (found in up to 27% of patients with aortic dissection)3,5
  • •Preexisting aortic aneurysm (found in up to 16% to 20% of patients with aortic dissection)3,5
  • •Age (60 to 80 yr)
  • •Family history of aortic aneurysms/dissection
  • •History of cardiac surgery, aortic valve replacement, intraaortic catheterization1,3,5
  • •Disorders of collagen (Marfan syndrome, Loeys-Dietz syndrome, Ehlers-Danlos syndrome)3,5
  • •Vascular inflammation (giant cell arteritis, Takayasu arteritis, rheumatoid arthritis, syphilitic aortitis)
  • •Aortic coarctation, bicuspid aortic valve
  • •Turner syndrome
  • •Cocaine abuse (usually within 12 h of last use of cocaine)1,3,5
  • •Trauma (∼20% road accident fatalities found to have ruptured aorta on autopsy)1
  • •Pregnancy and delivery
  • •Fluoroquinolone use1
  • •Table E3 summarizes genetically triggered conditions associated with aortic dissection

TABLE E2 Risk Factors for Aortic Dissection

  • Hypertension
  • Heritable or genetic thoracic aortic disease and syndromes
    • Marfan syndrome
    • Loeys-Dietz syndrome
    • Familial thoracic aortic aneurysm syndromes
    • Vascular Ehlers-Danlos syndrome
    • Turner syndrome
  • Congenital diseases/syndromes
    • Bicuspid aortic valve
    • Coarctation of the aorta
    • Tetralogy of Fallot
  • Atherosclerosis
    • Penetrating atherosclerotic ulcer
  • Trauma, blunt or iatrogenic
    • Catheter/guidewire
    • Intraaortic balloon pump
    • Aortic/vascular surgery
    • Motor vehicle accident
    • Coronary artery bypass grafting/aortic valve replacement/TAVR
    • Thoracic endovascular aneurysm repair (TEVAR)
  • Cocaine/methamphetamine use
  • Inflammatory/infectious diseases
    • Giant cell arteritis
    • Takayasu arteritis
    • Behçet syndrome
    • Aortitis
    • Syphilis
  • Pregnancy (with underlying aortopathy)
  • Weightlifting (with underlying aortopathy)

TAVR, Transcatheter aortic valve replacement.

From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

TABLE E3 Thoracic Aortic Aneurysm Syndromes and Conditions Due to a Heritable or Genetic Cause

ConditionGeneClinical Features
Syndromic HTAD*
Marfan syndromeFBN1Aortic root aneurysm, AD, TAA, MVP, long bone overgrowth, scoliosis, pectus deformities, ectopia lentis, myopia, tall stature, PTX, dural ectasia
Loeys-Dietz syndromeTGFBR1, TGFBR2,*SMAD3, TGFB2, TGFB3, SMAD2TAA, branch vessel aneurysms, AD, arterial tortuosity, MVP, craniosynostosis, hypertelorism, bluish sclera, bifid/broad uvula, translucent skin, visible veins, club feet, dural ectasia,* premature osteoarthritis
Vascular Ehlers-Danlos syndromeCOL3A1TAA, AAA, arterial rupture, AD, MVP, bowel and uterine rupture, PTX, translucent skin, atrophic scars, small joint hypermobility, easy bruising, carotid-cavernous fistula
Arterial tortuosity syndromeSLC2A10Tortuous large- and medium-sized arteries, aortic dilation, craniofacial, skin and skeletal features
Shprintzen-Goldberg syndromeSKICraniosynostosis, skeletal features, aortic dilation
Congenital contractural arachnodactyly (Beals syndrome)FBN2MVP, arachnodactyly, Marfanoid habitus, digital contractures, mild aortic dilation
Cutis laxaEFEMP2 (Fibulin-4)TAA, arterial tortuosity, arterial stenosis, hypertelorism, arachnodactyly
EDS with periventricular nodular heterotopia (PVNH)FLNA (filamin A)X-linked, PVNH, TAA, BAV, MV disease, PDA, VSD, seizures, joint hypermobility
Meester-Loeys syndromeBGNX-linked, TAA, AD, skeletal abnormalities
LOX-related TAALOX (lysyl oxidase)TAA, BAV, AD, Marfanoid habitus in some
Nonsyndromic HTAD (Familial TAA)
FTAAACTA2 (α-smooth muscle actin)TAA, AD, BAV, Moya-Moya, premature CAD and CVD, livedo reticularis, iris flocculi
FTAAMYH11 (myosin heavy chain-11)TAA, AD, PDA
FTAAMYLK (myosin light chain kinase)AD at relatively small aortic size
FTAAPRKG1 (protein kinase cGMP-dependent)Aortic root aneurysm and AD
FTAAMAT2A (MAT IIα)TAA, AD, BAV
FTAAMFAP5 (microfibrillar-associated protein 5)TAA, AD, skeletal features may be present
FTAAFOXE3 (forkhead transcription factor)TAA, AD
Bicuspid Aortic Valve/Associated Ascending Aortic Aneurysm
Familial BAV/AS and TAANOTCH1 (NOTCH1)Aortic stenosis, TAA
TGFBR1, TGFBR2, TGFB2, TGFB3, ACTA2, MAT2A, GATA5, SMAD6, LOX, ROBO4, TBX20BAV with TAASyndromic and nonsyndromic FTAA with an increased frequency of BAV
Turner syndromeXO, XpBAV, COA, TAA, AD, short stature, lymphedema, webbed neck, premature ovarian failure, affects 1 in 2500 live-born girls

AAA, Abdominal aortic aneurysm; AAT, aortic aneurysm syndrome; AD, aortic dissection; BAV, bicuspid aortic valve; CAD, coronary artery disease; COA, coarctation of the aorta; CVD, cerebrovascular disease; EDS, Ehlers-Danlos syndrome; FTAA, familial thoracic aortic aneurysm (and dissection) syndrome; HTAD, heritable TAA; LDS, Loeys-Dietz syndrome; MFS, Marfan syndrome; MV, mitral valve; MVP, mitral valve prolapse; PDA, patent ductus arteriosus; PTX, pneumothorax; TAA, thoracic aortic aneurysm; TGF, transforming growth factor; VSD, ventricular septal defect.

* Some individuals with pathogenic variants in a gene which can lead to syndromic HTAD have very few or no syndromic features, and variants in some genes causing syndromic HTAD may also lead to nonsyndromic HTAD.

From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

Physical Findings & Clinical Presentation

  • •Sudden onset of severe sharp, tearing, or ripping chest, back, or abdominal pain.1,3,5 However, painless dissection occurs in ∼6.3% of cases2
  • •Anterior chest pain (79% type A, 63% type B)3
  • •Back pain, abdominal pain (43% type A, 64% type B)3
  • •Syncope (19% type A, 3% type B), generally secondary to cardiac tamponade or stroke3
  • •Congestive heart failure (CHF)1
  • •May present with hypertension (28% for type A, 66% in type B dissection),5 although 25% present with hypotension (systolic blood pressure <100 mm Hg), which can indicate bleeding, cardiac tamponade, or severe aortic regurgitation.3 Patients presenting with very high systolic blood pressure (>180 mm Hg for type A, >200 mm Hg for type B dissection), as well as in those with systolic blood pressure ≤100 mm Hg, have significantly higher in-hospital mortality rates
  • •Pulse and blood pressure differentials (>20 mm Hg between arms) in 19% to 31% of cases caused by partial compression of subclavian arteries6
  • •Aortic regurgitation in 40% to 75% of cases of proximal dissection,1 often with diastolic decrescendo murmur
  • •Myocardial ischemia caused by coronary artery occlusion, most commonly involving the right coronary artery
  • •Stroke in 5% to 10% of patients (secondary to dissection into or decreased blood flow to the carotids)1
  • •Mesenteric ischemia occurs in 3% to 5% of cases, with external compression, flap prolapse, or involvement of arterial ostia1
  • •Horner syndrome (ptosis, miosis, anhidrosis)
  • •Vocal cord paralysis or hoarse voice (caused by compression of the left recurrent laryngeal nerve)1
Etiology

Genetics, in addition to other risk factors (Tables E4, E5, E6, and E7), contribute to the development of aortic aneurysms and dissection.

TABLE E4 Ascending Thoracic Aortic Aneurysms

DegenerativeAssociated With Atherosclerosis
Inheritable/connective tissueMarfan syndrome
Ehlers-Danlos syndrome
Loeys-Dietz syndrome
Turner syndrome
Osteogenesis imperfecta
Rheumatoid arthritis
Bicuspid aortic valve
Aneurysm of sinus of Valsalva
ArteritisGiant cell
Takayasu
Behçet disease
Relapsing polychondritis
InfectiousSyphilis
Mycotic aneurysms

From Soto JA, Lucey BC: Emergency radiology: the requisites, ed 2, Philadelphia, 2017, Elsevier.

TABLE E5 Aortic Arch Aneurysms

DegenerativeResulting From Atherosclerosis
ArteritisGiant cell
Takayasu
Behçet disease
InfectiousSyphilis

From Soto JA, Lucey BC: Emergency radiology: the requisites, ed 2, Philadelphia, 2017, Elsevier.

TABLE E6 Descending Thoracic Aortic Aneurysm

DegenerativeResulting From Atherosclerosis
Focal pseudoaneurysm resulting from a penetrating aortic ulcer
ArteritisGiant cell
Takayasu
Behçet disease
Inherited/connective tissueMarfan syndrome
Ductus aneurysm
Loeys-Dietz syndrome
InfectiousMycotic aneurysms
TraumaticPosttraumatic pseudoaneurysms
Chronic aortic transection

From Soto JA, Lucey BC: Emergency radiology: the requisites, ed 2, Philadelphia, 2017, Elsevier.

TABLE E7 Crawford Classification of Thoracoabdominal Aneurysms

IDescending thoracic aorta to suprarenal aorta
IIProximal descending thoracic aorta to infrarenal aorta (below the diaphragm)
IIIMid descending thoracic aorta to infrarenal aorta
IVSupravisceral aorta to infrarenal aorta

From Soto JA, Lucey BC: Emergency radiology: the requisites, ed 2, Philadelphia, 2017, Elsevier.

Diagnosis ⬆ ⬇

Differential Diagnosis

  • •Aortic dissection is known as the great imitator, as it is often mistaken for pulmonary embolism, acute coronary syndrome, aortic stenosis/insufficiency, nondissecting aneurysm, pericarditis, cholecystitis, peptic ulcer disease, pancreatitis, musculoskeletal pain.3
  • •Consider aortic dissection in patients with unexplained stroke, chest pain, syncope, acute-onset CHF, abdominal pain, back pain, and malperfusion of extremities or internal organs.3 Acute aortic syndromes may be associated with nonspecific signs and symptoms; a high clinical index of suspicion is necessary to detect the disease early in its course as nearly two thirds of patients under medical care are not diagnosed before death. Box E1 summarizes a differential diagnosis of aortic dissection.
  • •In an emergency situation, a rapid yet comprehensive workup is crucial to reduce diagnostic time delay. This should include clinical assessment, laboratory data (D-dimer and troponin), chest x-ray, ECG, and aortic imaging in the appropriate patient.1,3,5
  • •The Aortic Dissection Detection Risk Score (ADD-RS) can be a useful tool in diagnosing aortic dissection in the emergency room setting.6 ADD-RS is based on the presence of one or more of the clinical risk markers outlined in Table E8. A high ADD-RS effectively stratifies the risk for acute aortic dissection (score 0 is low risk, score 1 is intermediate risk, and score ≥2 is high risk).6 Score 0 has 95.6% certainty in ruling out aortic dissection.
  • •The addition of D-dimer to ADD-RS may further improve diagnostic performance of each of these when used alone for ruling out acute aortic dissection or other acute aortic syndromes.6 Among low- to intermediate-risk patients (ADD-RS <2), a negative D-dimer (<500 mg/dl) can rule out aortic dissection with 99.7% certainty.6 Among high-risk patients (ADD-RS ≥2), D-dimer is not discriminatory and requires conclusive imaging for definitive diagnosis.6

BOX E1 Differential Diagnosis of Aortic Dissection

  • Cardiovascular
    • Acute coronary syndrome with or without ST-segment elevation
    • Shock
    • Acute pulmonary edema
    • Acute valvular dysfunction
    • Pericarditis
    • Acute extremity ischemia
  • Pulmonary
    • Pulmonary embolus
    • Pneumothorax
  • Gastrointestinal
    • Pancreatitis
    • Peptic ulcer disease (including perforation)
    • Esophageal spasm/reflux
    • Ischemic bowel
  • Neurologic
    • Stroke/transient ischemic attack
    • Spinal cord compression
  • Renal
    • Renal colic

From Cameron P et al: Textbook of adult emergency medicine, ed 5, Australia, 2019, Elsevier.

TABLE E8 Aortic Dissection Detection Risk Score

High-Risk ConditionsHigh-Risk Pain FeaturesHigh-Risk Examination Features
Marfan syndrome
Family history of aortic disease
Known aortic valve disease
Recent aortic manipulation
Known thoracic aortic aneurysm
  • Chest, back, or abdominal pain described as any of the following:
    • Abrupt onset
    • Severe intensity
    • Ripping or tearing
  • Evidence of perfusion deficit:
    • Pulse deficit
  • Systolic BP differential
  • Focal neurologic deficit (in conjunction with pain)
  • Murmur of aortic insufficiency (new and with pain)
  • Hypotension or shock state

Any positive attribute in each column yields a score of 1 for that column. Each column can have a score of 1 or 0. The total ADD score is the sum of the 3 columns (on a scale of 0 to 3).

From Walls RM et al: Rosen’s emergency medicine, concepts and clinical practice, ed 10, Philadelphia, 2023, Elsevier.

Workup

  • •Diagnostic and treatment algorithms of aortic dissection are illustrated in Fig. E3.
  • •ECG: Helpful to rule out myocardial infarction, although dissection can lead to coronary ischemia.1,3,5

Figure E3 Diagnostic and treatment algorithms of aortic dissection.

APTT/PT, Activated partial thromboplastin time/prothrombin time; CBC, complete blood count; CT, computed tomography; CXR, chest x-ray; EKG, electrocardiogram; IVUS, intravascular ultrasound; MRI, magnetic resonance imaging; OR, operating room; TEE, transesophageal echocardiogram; TEVAR, thoracic endovascular aortic repair.

(Modified from Hiratzka LF et al: 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine, J Am Coll Cardiol 55[14]:e27-e129, 2010.)

Laboratory Tests

  • •D-Dimer has a high negative predictive value in dissection but lacks specificity in the setting of acute aortic dissection.1,3 However, a negative D-dimer does not rule out IMH or penetrating aortic ulcer.1,3
  • •Soluble ST2, a novel interleukin-1 receptor family member, is a biomarker that may have superior diagnostic performance over D-dimer in discriminating acute aortic dissection from other acute chest pain syndromes.7 At a cutoff level of 34.6 ng/ml, the sensitivity and specificity for acute aortic dissection were 99.1% and 84.9%, respectively.7
Imaging Studies

  • •Multidetector CT (Fig. E4) is considered the gold standard, but its use may be limited in patients with renal failure as it involves the use of intravenous contrast.1,3,5
  • •Transesophageal echocardiography (TEE), multidetector CT, and MRI are all highly sensitive (98% to 100%) and specific (95% to 98%).9 Test of choice depends on clinical circumstances and hospital availability.
  • •TEE is study of choice in unstable patients with type A dissection but is operator dependent. TEE is also useful in patients in whom radiation exposure is of concern, such as pregnant patients1
  • •MRI has high sensitivity and specificity but limited availability; not suitable for unstable patients; contraindicated with noncompatible pacemakers, metal devices; uses gadolinium-based contrast, which is less nephrotoxic than iodinated agents in patients without severe renal dysfunction.1
  • •With medium or high pretest probability, a second diagnostic test should be done if the first is negative.
  • •Coronary computed tomographic angiography (CTA) may be an alternative and useful diagnostic study when evaluating for pulmonary embolism, acute coronary syndrome, and aortic dissection.1
  • •Aortography rarely done, as less sensitive than TEE, CT, or MRI.1
  • •Chest radiograph may show widened mediastinum (52% in type A dissections and 39% in type B dissections) and displacement of aortic intimal calcium.4 It is normal in 29% to 36% of patients with aortic dissection.
  • •Although the diagnostic sensitivity of transthoracic echocardiography is suboptimal (31% to 55%), it is useful in assessing potential high-risk features or complications, such as pericardial effusion and cardiac tamponade, and in making other potential diagnoses. A negative transthoracic echocardiography, however, does not exclude aortic dissection.1

Figure E4 Contrast-Enhanced Computed Tomography Scan Demonstrating Acute Type A Aortic Dissection with Enlargement of the Ascending Aorta and Intimal Flaps (Arrows) in the Ascending and Descending Aorta

Both the true lumen (TL) and the false lumen are opacified with contrast material in this example.

(From Mann DL et al: Braunwald’s heart disease, ed 10, Philadelphia, 2015, Elsevier.)

Treatment ⬆ ⬇

TABLE E9 Size Threshold for Prophylactic Aortic Root or Ascending Aortic Aneurysm Resection for Various Conditions

ConditionSize Threshold*
Degenerative aneurysm≥5.5 cm
Bicuspid aortic valve≥5.5 cm
Bicuspid aortic valve with risk factors or low surgical risk†≥5.0 cm
Bicuspid aortic valve requiring aortic valve replacement>4.5 cm
Marfan syndrome≥5.0 cm
Marfan syndrome with risk factors‡>4.5 cm
Loeys-Dietz syndrome§4.0-4.5 cm
Familial thoracic aortic aneurysm syndromes4.5-5.0 cm
Turner syndrome>2.5 cm/m2

* Lower thresholds for intervention may be considered according to body surface area in patients of small stature or in the case of rapid growth of the aorta. Age, body size, rapid growth, family history, risk of surgery, and patient and physician wishes may influence aortic size threshold.

† Family history of aortic dissection or aortic growth rate of ≥0.5 cm/yr or if the patient is at low surgical risk (<4%) and the surgery is performed by an experienced aortic surgical team in a center with established expertise in these procedures. Other risk factors for aortic dissection include coarctation of the aorta, hypertension, and the root phenotype of bicuspid aortic valve.

‡ Family history of aortic dissection or rapid aortic growth (>3 mm/yr), or severe aortic or mitral regurgitation. If pregnancy desired, consider prophylactic aortic surgery for aortic diameter of 4.0-4.5 cm.

§ It is reasonable to consider surgical repair of the aorta in adults with Loeys-Dietz syndrome or a confirmed TGFBR1 or TGFBR2 mutation with aortic diameter of 4.2 cm or more by transesophageal echocardiogram or 4.4-4.6 or more by CT or MRI. Aortic surgery at smaller diameters may be recommended when there are severe craniofacial features, rapid growth, or a family history of aortic dissection.

Surgical thresholds vary depending on the specific gene mutation involved. TAA caused by ACTA2, SMAD3, and MYLK may lead to aortic dissection at relatively small aortic diameters.

Adapted from Erbel R et al: 2014 ESC guidelines on the diagnosis and treatment of aortic diseases: document covering acute and chronic aortic diseases of the thoracic and abdominal aorta of the adult. The Task Force for the Diagnosis and Treatment of Aortic Diseases of the European Society of Cardiology (ESC). Eur Heart J 35:2873-2926, 2014; Hiratzka LF et al: 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease. Circulation 121:e266-e369, 2010; Hiratzka LF et al: Surgery for aortic dilatation in patients with bicuspid aortic valves: a statement of clarification from the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol 67:724-731, 2016; Silberbach M et al: Cardiovascular health in Turner syndrome: a scientific statement from the American Heart Association. Circ Genom Precis Med 11(10):e000048, 2018. In Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

TABLE E10 Indications for Thoracic Endovascular Aortic Repair for Complicated Type B Aortic Dissection (or Open Surgical Repair if Anatomy Is Unsuitable for Thoracic Endovascular Aortic Repair)

Rupture/impending rupture
Malperfusion
Hemothorax
Refractory pain
Refractory hypertension
Aneurysmal dilation (>55 mm)
Rapid increase in aortic diameter
Recurrent symptoms

From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

Figure E5 Management algorithm for acute type B aortic dissection.

!!flowchart!!

Adjunctive procedures are, for example, endovascular fenestration, surgical revascularization, coil embolization, and selective branch vessel stenting. High-risk features include primary entry tear diameter greater than 10 mm, initial aortic diameter greater than 40 mm, false lumen diameter greater than 22 mm, partially thrombosed false lumen, and saccular false lumen formation. OMT, Optimal medical therapy; TEVAR, thoracic endovascular aortic repair.

(From Tadros RO et al: Optimal treatment of uncomplicated type B aortic dissection: JACC review topic of the week. J Am Coll Cardiol 74: 1494-1504, 2019.)

Acute General Rx

  • •Admit to ICU for monitoring.
  • •Target systolic blood pressure 100 to 120 mm Hg; heart rate <60 beats/min to reduce aortic wall stress.1,11 Treatment with beta-blockers has been associated with improved survival in all patients with acute aortic dissections. Selected pharmacologic therapy for acute aortic dissection is summarized in Table E11.
  • •IV beta-blockers are cornerstones of treatment, but multiple medications may be needed.
    1. 1.Propranolol 1 mg every 3 to 5 min, metoprolol 5 mg IV every 5 min, or labetalol 20 mg IV, then 20 to 80 mg every 10 min, followed by nitroprusside 0.3 to 10 mcg/kg/min.11 If this is not effective at achieving BP or HR goals, an IV esmolol drip, titratable between 0 and 300 mcg/kg/min, is often used.
    2. 2.Vasodilators should not be used without beta-blockade as they can induce reflex sympathetic stimulation and increase aortic shear stress.11
    3. 3.IV calcium channel blockers with negative inotropy (i.e., verapamil, diltiazem) may be used if beta-blockers are contraindicated.11
  • •Pain control, often with an opiate.11

TABLE E11 Selected Pharmacologic Therapy for Acute Aortic Dissection*

Intravenous Beta-Blocker (Preferred Negative Inotrope)
  • •Esmolol: Bolus 250-500 μg/kg IV, then continuous IV infusion at 50-100 μg/kg/min, titrated to effect with maximum dose of 200 μg/kg/min
  • •Labetalol: Bolus 20 mg IV over 2 min, then 20-80 mg IV every 10 min until adequate response (maximum 300 mg), then continuous IV infusion at 0.5-2 mg/min IV, titrated to effect
  • •Metoprolol: Give 2.5-15 mg IV followed by 2.5-15 mg IV every 3-6 h
Intravenous Calcium Channel Blocker (Secondary Negative Inotrope)
  • •Diltiazem: Initial bolus of 0.25-0.35 mg/kg IV, then continuous IV infusion of 5-20 mg/h
  • •Verapamil: 5-10 mg IV and may repeat after 5-10 min
Intravenous Vasodilator (After Initiation of Negative Inotrope)
  • •Clevidipine: Give 1-2 mg/h; can double dose up to maximum dose of 16-32 mg/h
  • •Sodium nitroprusside: Start continuous infusion at 0.25-0.5 μg/kg/min, titrated to a maximum of 8-10 μg/min. Use only in presence of beta blockers.
  • •Caution: Thiocyanate toxicity may occur in patients with renal impairment or prolonged infusions
  • •Nicardipine: Give 2.5-5 mg/h and titrate up to a maximum of 15 mg/h
  • •Nitroglycerin: Initial 5 μg/min; up to 200 μg/min as an IV infusion
  • •Enalaprilat: Give 1.25 mg, then 1.25-5 mg IV every 6 h, titrated to effect
  • •Fenoldopam: Give 0.1 μg/kg/min and titrate up to a maximum of 1.6 μg/kg/min

* Goal of therapy is heart rate less than 70 beats/min and blood pressure 100-120 mm Hg or as low as possible without compromising organ perfusion.

From Libby P et al: Braunwald’s heart disease, a textbook of cardiovascular medicine, ed 12, Philadelphia, 2022, Elsevier.

Chronic Rx

  • •Chronic aortic dissection (>2 wk) managed with aggressive blood pressure control; target <130/80 mm Hg in most patients1,11
  • •Statin therapy to reduce low-density lipoprotein <70 mg/dl11
  • •Tobacco cessation11
  • •Minimize strenuous physical activity such as heavy lifting11
  • •Serial imaging of the aorta, with multidetector CT or MRI should be performed at presentation, at 1, 3, 6, and 12 mo given the higher risk of instability early on, followed by yearly clinical and imaging follow-up11
  • •As stated above, endovascular repair should be considered in complicated chronic type B dissections when the aortic diameter exceeds 5.5 cm, when there is uncontrolled pain or blood pressure, or when there is rapid growth of the dissecting aneurysm (>4 mm per yr)11
Disposition

  • •90% mortality rate is within 2 wk for an untreated type A dissection.
  • •Proximal dissection is a surgical emergency. Time is critical; mortality rate is 1% to 3%/h, approaching 70% after 48 h.1,11
  • •Overall, in-hospital mortality rate is 22% with proximal dissections (27% treated surgically and 56% treated medically) and 13% with distal dissections.3
  • •Table E12 summarizes suggested imaging surveillance of asymptomatic thoracic aortic aneurysms.

TABLE E12 Suggested Imaging Surveillance of Asymptomatic Thoracic Aortic Aneurysms*

Initial Discovery of AneurysmRepeated Imaging at 6 mo to Document Stability
Degenerative Aneurysm†
3.5-4.4 cmAnnual imaging
4.5-5.4 cmAnnual to biannual imaging
MFS, BAV With TAA, and Familial TAA
3.5-4.4 cmAnnual imaging
4.5-5.0 cmBiannual imaging
LDS‡
<4 cmAt least annual imaging
>4 cmBiannual imaging

BAV, Bicuspid aortic valve; LDS, Loeys-Dietz syndrome; MFS, Marfan syndrome; TAA, thoracic aortic aneurysm.

* For aneurysms growing rapidly, more frequent imaging is recommended. Management of TAA must take into account the family history, age, body size, sex, rate of aneurysm growth, and underlying disease.

† For relatively small degenerative aneurysms found by imaging to be stable from year to year, imaging may be performed every 2-3 yr (Hiratzka et al).

‡ Some recommend surgery for aortic root dimensions larger than 4 cm in adults with LDS, whereas the American College of Cardiology/American Heart Association guidelines for thoracic aortic disease recommend prophylactic surgery at 4.2 cm by TEE and 4.4-4.6 cm by CT or MRI (Hiratzka et al).

From Hiratzka LF et al: 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine, Circulation 121:e266, 2010; Mann DL et al: Braunwald’s heart disease, ed 10, Philadelphia, 2015, Elsevier.

Referral

For ICU management and surgical intervention

Pearls & Considerations ⬆ ⬇

Other Acute Aortic Syndromes
Acute Intramural Hematoma:

  • •Acute IMH occurs when the vasa vasorum ruptures within the medial wall. It does not involve an intimal tearing unless a dissection develops.
  • •About 10% to 20% of patients with suspected aortic dissection will be found to have acute IMH.11
  • •The key imaging findings are the absence of intimal tear and absence of blood flow into a false lumen.
  • •Echocardiography shows crescentic or circumferential thickening of aortic wall without an intimal flap.
  • •About 8% to 16% of patients with IMH will evolve into aortic dissection.3
  • •Management remains controversial, but in the ascending aorta, IMH is generally treated with urgent surgical repair.
  • •Similar to aortic dissections, in-hospital mortality is significantly worse among patients with type A IMH compared to type B.3
Penetrating Atherosclerotic Ulcer:

  • •Penetrating atherosclerotic ulcers occur in the setting of extensive aortic atherosclerosis and hypertension.11
  • •These are seen mostly in older adults and occur in descending aorta in over 90% of cases.11
  • •There is an ulceration of atheroma that disrupts the internal elastic lamina and extends into the media and allows hematoma formation.11
  • •They should be treated promptly, because there is potential for extensive IMH, pseudoaneurysm or complete rupture of aorta.11

The general principles of the treatment of acute IMHs and penetrating atherosclerotic ulcers are similar to acute aortic dissection.11

Related Content

  • Aortic Dissection (Patient Information)

Reference(s) ⬆

  1. Erbel R : ESC guidelines on the diagnosis and treatment of aortic diseasesEur Heart J. 35(41):2873-2926, 2014.
  2. Lombardi J : Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) reporting standards for type B aortic dissectionsJ Vasc Surg. 71(3):723-747, 2020.
  3. Evangelista A : Insights from the International Registry of Acute Aortic Dissection: a 20-year experience of collaborative clinical researchhttp://dx.doi.org/10.1161/CIRCULATIONAHA.117.031264Circulation. 137(17):1846-1860, 2018.
  4. Takagi H : Meta-analysis of seasonal incidence of aortic dissectionAm J Cardiol. 120:700, 2017.
  5. Pape LA : Presentation, diagnosis, and outcomes of acute aortic dissection: 17-year trends from the International Registry of Acute Aortic DissectionJ Am Coll Cardiol. 66:350-358, 2015.
  6. Nazerian P : Diagnostic accuracy of the aortic dissection detection risk score plus D-dimer for acute aortic syndromes: The ADvISED Prospective Multicenter Studyhttp://dx.doi.org/10.1161/CIRCULATIONAHA.117.029457Circulation. 137:250-258, 2018.
  7. Wang Y : Magnitude of soluble ST2 as a novel biomarker for acute aortic dissectionhttp://dx.doi.org/10.1161/CIRCULATIONAHA.117.030469Circulation. 137:259-269, 2018.
  8. Fukui T : Management of acute aortic dissection and thoracic aortic rupturehttp://dx.doi.org/10.1186/s40560-018-0287-7J Intensive Car. 6(15), 2018.
  9. Song JM : Long-term predictors of descending aorta aneurysmal change in patients with aortic dissectionJ Am Coll Cardiol. 50:799-804, 2007.
  10. Fattori R : Interdisciplinary expert consensus document on management of type B aortic dissectionJ Am Coll Cardiol. 61(16):1661-1678, 2013.
  11. Hiratzka LF : 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular MedicineCirculation. 121:e266-e369, 2010.