link
Bookmarks
Thoracic Aorta and Great Vessels
Kalie Adler, DO; Brandt C. Wible, MD; Zubin Irani, MD
To access 4,300 diagnoses written by the world's leading experts in radiology, please log in or subscribe.Log inSubscribe

KEY FACTS

  • Terminology

    • Procedure

      • Outcomes

        TERMINOLOGY

        • Definitions

          • Acute aortic syndromes: Spectrum of abnormalities that acutely compromise aortic wall integrity
            • Thoracic aortic dissection (AD): Intimal tear extends into aortic wall; blood flows between/separates wall layers
              • Blood flow separates aortic wall structures, producing "true" & "false" lumina
                • Aortic branch vessel perfusion may be compromised; end-organ ischemia may result
              • Weakened aortic wall may rupture; high mortality
                • Chronic dissection may progress to aneurysm
            • Intramural hematoma (IMH): Hemorrhage within aortic wall media without initial intimal disruption
              • May occur as 1° event in hypertensive patients
                • Spontaneous bleeding from vasa vasorum into aortic media causing hematoma formation
              • May result from penetrating atherosclerotic ulcer (PAU)
              • Intramural hematoma weakens aortic wall
                • May spontaneously progress to aortic dissection if intimal layer ruptures ("entry tear")
                • Increased risk of aortic rupture
                • Association with ulcer-like projection in arch or ascending aorta indicative of intimal disruption
              • May resolve over time, persist, or evolve into aneurysm or PAU
              • Prognosis worsens if associated with ulcer-like projection, IMH > 2 cm thick, aortic diameter > 5 cm, or pleural or pericardial effusion
            • PAU: Plaque rupture through aortic internal elastic membrane
              • Often in patients with extensive intimal calcifications & atherosclerotic plaques
              • Ulcer/hematoma weakens aortic wall
                • May progress to aortic dissection
                • May form saccular pseudoaneurysm
                • Increased risk of acute rupture
              • May be single or multiple
              • Often with associated intramural hematoma
          • Thoracic aortic aneurysm (TAA): Aortic dilatation exceeding normal diameter by > 50%
            • Various etiologies
              • Degenerative: Commonly due to atherosclerosis
                • Abnormal matrix metalloproteinase activity
                • Etiology in 75% of thoracic aortic aneurysms
              • Connective tissue disorders: Genetic conditions associated with acute aortic syndromes/aneurysms
                • Ehlers-Danlos syndrome: Type IV vascular subgroup characterized by generalized vascular fragility; frequent arterial ruptures
                • Loeys-Dietz syndrome: Phenotypically similar to Ehlers-Danlos type IV subgroup
                • Marfan syndrome: Cystic medial degeneration; usually involves aortic root (annuloaortic ectasia)
                • Cystic medial necrosis
              • Infection (mycotic): Localized infection weakens/compromises integrity of aortic wall
                • Typically saccular configuration
              • Pseudoaneurysm: Disruption of 1 or more arterial wall layers; forms contained rupture
                • May be due to aortic injury following penetrating or blunt trauma (e.g., deceleration injury)
                • Also associated with infectious, inflammatory, & neoplastic disease
            • Increased rupture risk if TAA > 5 cm diameter or growth of > 1-cm per year
              • Rupture risk doubles per 1 cm aneurysm increment
            • Great vessel aneurysms: Account for only 1-3% of all arterial aneurysms
              • Brachiocephalic artery most commonly involved
                • Same etiologies as thoracic aortic aneurysms
          • Stenoses/occlusions of thoracic aorta & great vessels
            • Atherosclerosis: Most common cause
              • Severe stenoses may progress to chronic occlusion
              • Often occur at/near origins from thoracic aorta
            • Coarctation: Congenital condition in which thoracic aorta narrows in region where ductus arteriosus inserts; 3 subtypes
              • Preductal: Occurs proximal to ductus arteriosus
                • Due to decreased left heart blood flow from fetal cardiac anomaly; leads to hypoplastic aorta
                • Aortic perfusion distal to narrowing relies on ductus arteriosus; can be life-threatening if severe
                • Occurs in ~ 5% of infants with Turner syndrome
              • Ductal: Narrowing at ductus arteriosus insertion
                • Usually appears when ductus arteriosus closes
              • Postductal: Narrowing distal to ductus arteriosus
                • Likely due to contraction & fibrosis of ductus arteriosus at birth, subsequently narrowing aorta
                • Most common type in adults
            • Pseudocoarctation: Rare congenital anomaly in which kinking/buckling of thoracic aorta occurs; resembles true thoracic coarctation on imaging
              • Involves descending thoracic aorta immediately distal to left subclavian artery origin
              • Differentiated from true coarctation by absence of significant hemodynamic obstruction
            • Subclavian steal syndrome: Retrograde flow in vertebral &/or internal mammary artery due to proximal subclavian artery stenosis or occlusion
              • Can cause posterior fossa ischemia resulting in ataxia, dizziness
              • May also present with arm claudication
          • Vasculitis
            • Giant cell arteritis (GCA): Vasculitis affecting medium to large-caliber arteries; similar to Takayasu arteritis & may represent single disease spectrum
              • Age at onset often used to classify patients
                • GCA affects older population (> 50 years)
                • Classically involves temporal arteries &/or cervical carotid arteries
              • 20-30% of patients with GCA have involvement of aorta & primary branches
                • May cause long stenoses of mid/distal subclavian arteries, extending into axillary arteries; seen more frequently in GCA than in Takayasu
              • Diagnosis confirmed by arterial biopsy
                • Typically biopsy of temporal artery; easily accessible & usually involved when disease present
                • Mononuclear cell infiltration/granulomatous inflammation with multinucleated giant cells
            • Takayasu arteritis: Large vessel granulomatous inflammatory vasculitis
              • Affects people younger than 40 years
                • Often occurs between 15-30 years
              • Classically characterized by 3 stages
                • Active inflammation; constitutional symptoms
                • Vascular inflammation; vessel pain/tenderness
                • Vascular fibrosis or degeneration causing ischemia or aneurysms
              • Involves thoracoabdominal aorta &/or primary branches, pulmonary arteries
        • Pertinent Vascular Anatomy

          • Brachiocephalic (innominate) artery: 1st branch of thoracic aorta; divides into right common carotid & right subclavian arteries
            • Right common carotid artery: Supplies face & right cerebral hemisphere; divides into external & internal carotid arteries
            • Right subclavian artery: Supplies right arm with some branches to head & thorax; becomes axillary artery at lateral margin of 1st rib
              • Vertebral artery: Supplies cerebellum
              • Internal mammary artery: Yields anterior intercostals, breast perforators; terminates as superior epigastric & musculophrenic arteries
              • Costocervical trunk: Divides into supreme intercostal & deep cervical arteries
              • Thyrocervical trunk: Divides into inferior thyroid, suprascapular & transverse cervical arteries
              • Dorsal scapular artery: Supplies levator scapulae, rhomboid & trapezius muscles
          • Left common carotid artery: 2nd branch of thoracic aorta; divides into external & internal carotid arteries
          • Left subclavian artery: 3rd branch of thoracic aorta; yields same branches as right subclavian artery
        • Significant Variant Vascular Anatomy

          • Aberrant right subclavian artery: Arises as last branch of aortic arch; most common clinically significant aortic arch malformation (0.4-2.3% incidence)
            • Usually passes posterior to trachea & esophagus
              • Patients rarely symptomatic; can cause stridor &/or swallowing difficulties (dysphagia lusoria)
            • Diverticulum of Kommerell: Conical dilatation of aberrant right subclavian artery origin
              • Represents distal remnant of right aortic arch
              • Large diverticulum can be symptomatic
                • 19% present with rupture
                • Can also present with distal embolization
          • Right aortic arch
            • With aberrant left subclavian artery: Most common type of right aortic arch (0.1% incidence)
              • Arch courses over right mainstem bronchus but may descend on either side of spine; left subclavian artery is last aortic branch
              • Associated with diverticulum of Kommerell
              • Associated congenital heart disease in 5-10%
                • Tetralogy of Fallot (71%)
                • Atrial or ventricular septal defect (21%)
                • Aortic coarctation rarely (7%)
            • With mirror-image branching: Descending aorta almost always courses to right of spine
              • Left innominate artery followed by right carotid & right subclavian arteries; no retroesophageal vessel
              • Associated congenital heart disease in 90-95%
                • Tetralogy of Fallot (90%)
                • Truncus arteriosis (6%)
                • Tricuspid atresia (5%)
          • Double aortic arch
            • Most common vascular ring
              • Aortic arches pass on both sides of trachea, join posterior to esophagus
                • Right arch larger & higher, supplies right subclavian & common carotid arteries
                • Smaller & lower left aortic arch supplies left subclavian & common carotid arteries
            • Rarely associated with congenital heart disease
              • Clinical symptoms of dysphagia &/or stridor
          • Cervical aortic arch
            • Rare anomaly; usually asymptomatic
              • May present as pulsating supraclavicular mass
              • May rarely produce vascular ring, compress airway
            • Right-sided location in over 80%
              • Branching may be normal or mirror image

        PREPROCEDURE

        • Indications

          • Contraindications

            • Preprocedure Imaging

              • Getting Started

                PROCEDURE

                • Patient Position/Location

                  • Procedure Steps

                    • Alternative Procedures/Therapies

                      OUTCOMES

                      • Complications

                        • Expected Outcomes

                          Selected References

                          1. Mussa FF et al: Acute aortic dissection and intramural hematoma: a systematic review. JAMA. 316(7):754-63, 2016
                          2. Harris KM et al: Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection. Circulation. 126(11 Suppl 1):S91-6, 2012
                          3. Waterman AL et al: Endovascular treatment of acute and chronic aortic pathology in patients with Marfan syndrome. J Vasc Surg. 55(5):1234-41, 2012
                          4. Aiello F et al: Open and endovascular management of subclavian and innominate arterial pathology. Semin Vasc Surg. 24(1):31-5, 2011
                          5. Yuan SM et al: Cystic medial necrosis: pathological findings and clinical implications. Rev Bras Cir Cardiovasc. 26(1):107-15, 2011
                          6. Chao CP et al: Natural history and CT appearances of aortic intramural hematoma. Radiographics. 29(3):791-804, 2009
                          7. Patel SN et al: Catheter-based treatment of the subclavian and innominate arteries. Catheter Cardiovasc Interv. 71(7):963-8, 2008
                          8. van Hattum ES et al: Angioplasty with or without stent placement in the brachiocephalic artery: feasible and durable? A retrospective cohort study. J Vasc Interv Radiol. 18(9):1088-93, 2007
                          9. Brountzos EN et al: Endovascular treatment of occlusive lesions of the subclavian and innominate arteries. Cardiovasc Intervent Radiol. 29(4):503-10, 2006
                          10. Chambers CM et al: Treatment of nonaortic aneurysms in the endograft era: aneurysms of the innominate and subclavian arteries. Semin Vasc Surg. 18(4):184-90, 2005
                          11. Sueyoshi E et al: New development of an ulcerlike projection in aortic intramural hematoma: CT evaluation. Radiology 224: 536-41, 2002
                          Related Anatomy
                          Loading...
                          Related Differential Diagnoses
                          Loading...
                          References
                          Tables

                          Tables

                          KEY FACTS

                          • Terminology

                            • Procedure

                              • Outcomes

                                TERMINOLOGY

                                • Definitions

                                  • Acute aortic syndromes: Spectrum of abnormalities that acutely compromise aortic wall integrity
                                    • Thoracic aortic dissection (AD): Intimal tear extends into aortic wall; blood flows between/separates wall layers
                                      • Blood flow separates aortic wall structures, producing "true" & "false" lumina
                                        • Aortic branch vessel perfusion may be compromised; end-organ ischemia may result
                                      • Weakened aortic wall may rupture; high mortality
                                        • Chronic dissection may progress to aneurysm
                                    • Intramural hematoma (IMH): Hemorrhage within aortic wall media without initial intimal disruption
                                      • May occur as 1° event in hypertensive patients
                                        • Spontaneous bleeding from vasa vasorum into aortic media causing hematoma formation
                                      • May result from penetrating atherosclerotic ulcer (PAU)
                                      • Intramural hematoma weakens aortic wall
                                        • May spontaneously progress to aortic dissection if intimal layer ruptures ("entry tear")
                                        • Increased risk of aortic rupture
                                        • Association with ulcer-like projection in arch or ascending aorta indicative of intimal disruption
                                      • May resolve over time, persist, or evolve into aneurysm or PAU
                                      • Prognosis worsens if associated with ulcer-like projection, IMH > 2 cm thick, aortic diameter > 5 cm, or pleural or pericardial effusion
                                    • PAU: Plaque rupture through aortic internal elastic membrane
                                      • Often in patients with extensive intimal calcifications & atherosclerotic plaques
                                      • Ulcer/hematoma weakens aortic wall
                                        • May progress to aortic dissection
                                        • May form saccular pseudoaneurysm
                                        • Increased risk of acute rupture
                                      • May be single or multiple
                                      • Often with associated intramural hematoma
                                  • Thoracic aortic aneurysm (TAA): Aortic dilatation exceeding normal diameter by > 50%
                                    • Various etiologies
                                      • Degenerative: Commonly due to atherosclerosis
                                        • Abnormal matrix metalloproteinase activity
                                        • Etiology in 75% of thoracic aortic aneurysms
                                      • Connective tissue disorders: Genetic conditions associated with acute aortic syndromes/aneurysms
                                        • Ehlers-Danlos syndrome: Type IV vascular subgroup characterized by generalized vascular fragility; frequent arterial ruptures
                                        • Loeys-Dietz syndrome: Phenotypically similar to Ehlers-Danlos type IV subgroup
                                        • Marfan syndrome: Cystic medial degeneration; usually involves aortic root (annuloaortic ectasia)
                                        • Cystic medial necrosis
                                      • Infection (mycotic): Localized infection weakens/compromises integrity of aortic wall
                                        • Typically saccular configuration
                                      • Pseudoaneurysm: Disruption of 1 or more arterial wall layers; forms contained rupture
                                        • May be due to aortic injury following penetrating or blunt trauma (e.g., deceleration injury)
                                        • Also associated with infectious, inflammatory, & neoplastic disease
                                    • Increased rupture risk if TAA > 5 cm diameter or growth of > 1-cm per year
                                      • Rupture risk doubles per 1 cm aneurysm increment
                                    • Great vessel aneurysms: Account for only 1-3% of all arterial aneurysms
                                      • Brachiocephalic artery most commonly involved
                                        • Same etiologies as thoracic aortic aneurysms
                                  • Stenoses/occlusions of thoracic aorta & great vessels
                                    • Atherosclerosis: Most common cause
                                      • Severe stenoses may progress to chronic occlusion
                                      • Often occur at/near origins from thoracic aorta
                                    • Coarctation: Congenital condition in which thoracic aorta narrows in region where ductus arteriosus inserts; 3 subtypes
                                      • Preductal: Occurs proximal to ductus arteriosus
                                        • Due to decreased left heart blood flow from fetal cardiac anomaly; leads to hypoplastic aorta
                                        • Aortic perfusion distal to narrowing relies on ductus arteriosus; can be life-threatening if severe
                                        • Occurs in ~ 5% of infants with Turner syndrome
                                      • Ductal: Narrowing at ductus arteriosus insertion
                                        • Usually appears when ductus arteriosus closes
                                      • Postductal: Narrowing distal to ductus arteriosus
                                        • Likely due to contraction & fibrosis of ductus arteriosus at birth, subsequently narrowing aorta
                                        • Most common type in adults
                                    • Pseudocoarctation: Rare congenital anomaly in which kinking/buckling of thoracic aorta occurs; resembles true thoracic coarctation on imaging
                                      • Involves descending thoracic aorta immediately distal to left subclavian artery origin
                                      • Differentiated from true coarctation by absence of significant hemodynamic obstruction
                                    • Subclavian steal syndrome: Retrograde flow in vertebral &/or internal mammary artery due to proximal subclavian artery stenosis or occlusion
                                      • Can cause posterior fossa ischemia resulting in ataxia, dizziness
                                      • May also present with arm claudication
                                  • Vasculitis
                                    • Giant cell arteritis (GCA): Vasculitis affecting medium to large-caliber arteries; similar to Takayasu arteritis & may represent single disease spectrum
                                      • Age at onset often used to classify patients
                                        • GCA affects older population (> 50 years)
                                        • Classically involves temporal arteries &/or cervical carotid arteries
                                      • 20-30% of patients with GCA have involvement of aorta & primary branches
                                        • May cause long stenoses of mid/distal subclavian arteries, extending into axillary arteries; seen more frequently in GCA than in Takayasu
                                      • Diagnosis confirmed by arterial biopsy
                                        • Typically biopsy of temporal artery; easily accessible & usually involved when disease present
                                        • Mononuclear cell infiltration/granulomatous inflammation with multinucleated giant cells
                                    • Takayasu arteritis: Large vessel granulomatous inflammatory vasculitis
                                      • Affects people younger than 40 years
                                        • Often occurs between 15-30 years
                                      • Classically characterized by 3 stages
                                        • Active inflammation; constitutional symptoms
                                        • Vascular inflammation; vessel pain/tenderness
                                        • Vascular fibrosis or degeneration causing ischemia or aneurysms
                                      • Involves thoracoabdominal aorta &/or primary branches, pulmonary arteries
                                • Pertinent Vascular Anatomy

                                  • Brachiocephalic (innominate) artery: 1st branch of thoracic aorta; divides into right common carotid & right subclavian arteries
                                    • Right common carotid artery: Supplies face & right cerebral hemisphere; divides into external & internal carotid arteries
                                    • Right subclavian artery: Supplies right arm with some branches to head & thorax; becomes axillary artery at lateral margin of 1st rib
                                      • Vertebral artery: Supplies cerebellum
                                      • Internal mammary artery: Yields anterior intercostals, breast perforators; terminates as superior epigastric & musculophrenic arteries
                                      • Costocervical trunk: Divides into supreme intercostal & deep cervical arteries
                                      • Thyrocervical trunk: Divides into inferior thyroid, suprascapular & transverse cervical arteries
                                      • Dorsal scapular artery: Supplies levator scapulae, rhomboid & trapezius muscles
                                  • Left common carotid artery: 2nd branch of thoracic aorta; divides into external & internal carotid arteries
                                  • Left subclavian artery: 3rd branch of thoracic aorta; yields same branches as right subclavian artery
                                • Significant Variant Vascular Anatomy

                                  • Aberrant right subclavian artery: Arises as last branch of aortic arch; most common clinically significant aortic arch malformation (0.4-2.3% incidence)
                                    • Usually passes posterior to trachea & esophagus
                                      • Patients rarely symptomatic; can cause stridor &/or swallowing difficulties (dysphagia lusoria)
                                    • Diverticulum of Kommerell: Conical dilatation of aberrant right subclavian artery origin
                                      • Represents distal remnant of right aortic arch
                                      • Large diverticulum can be symptomatic
                                        • 19% present with rupture
                                        • Can also present with distal embolization
                                  • Right aortic arch
                                    • With aberrant left subclavian artery: Most common type of right aortic arch (0.1% incidence)
                                      • Arch courses over right mainstem bronchus but may descend on either side of spine; left subclavian artery is last aortic branch
                                      • Associated with diverticulum of Kommerell
                                      • Associated congenital heart disease in 5-10%
                                        • Tetralogy of Fallot (71%)
                                        • Atrial or ventricular septal defect (21%)
                                        • Aortic coarctation rarely (7%)
                                    • With mirror-image branching: Descending aorta almost always courses to right of spine
                                      • Left innominate artery followed by right carotid & right subclavian arteries; no retroesophageal vessel
                                      • Associated congenital heart disease in 90-95%
                                        • Tetralogy of Fallot (90%)
                                        • Truncus arteriosis (6%)
                                        • Tricuspid atresia (5%)
                                  • Double aortic arch
                                    • Most common vascular ring
                                      • Aortic arches pass on both sides of trachea, join posterior to esophagus
                                        • Right arch larger & higher, supplies right subclavian & common carotid arteries
                                        • Smaller & lower left aortic arch supplies left subclavian & common carotid arteries
                                    • Rarely associated with congenital heart disease
                                      • Clinical symptoms of dysphagia &/or stridor
                                  • Cervical aortic arch
                                    • Rare anomaly; usually asymptomatic
                                      • May present as pulsating supraclavicular mass
                                      • May rarely produce vascular ring, compress airway
                                    • Right-sided location in over 80%
                                      • Branching may be normal or mirror image

                                PREPROCEDURE

                                • Indications

                                  • Contraindications

                                    • Preprocedure Imaging

                                      • Getting Started

                                        PROCEDURE

                                        • Patient Position/Location

                                          • Procedure Steps

                                            • Alternative Procedures/Therapies

                                              OUTCOMES

                                              • Complications

                                                • Expected Outcomes

                                                  Selected References

                                                  1. Mussa FF et al: Acute aortic dissection and intramural hematoma: a systematic review. JAMA. 316(7):754-63, 2016
                                                  2. Harris KM et al: Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection. Circulation. 126(11 Suppl 1):S91-6, 2012
                                                  3. Waterman AL et al: Endovascular treatment of acute and chronic aortic pathology in patients with Marfan syndrome. J Vasc Surg. 55(5):1234-41, 2012
                                                  4. Aiello F et al: Open and endovascular management of subclavian and innominate arterial pathology. Semin Vasc Surg. 24(1):31-5, 2011
                                                  5. Yuan SM et al: Cystic medial necrosis: pathological findings and clinical implications. Rev Bras Cir Cardiovasc. 26(1):107-15, 2011
                                                  6. Chao CP et al: Natural history and CT appearances of aortic intramural hematoma. Radiographics. 29(3):791-804, 2009
                                                  7. Patel SN et al: Catheter-based treatment of the subclavian and innominate arteries. Catheter Cardiovasc Interv. 71(7):963-8, 2008
                                                  8. van Hattum ES et al: Angioplasty with or without stent placement in the brachiocephalic artery: feasible and durable? A retrospective cohort study. J Vasc Interv Radiol. 18(9):1088-93, 2007
                                                  9. Brountzos EN et al: Endovascular treatment of occlusive lesions of the subclavian and innominate arteries. Cardiovasc Intervent Radiol. 29(4):503-10, 2006
                                                  10. Chambers CM et al: Treatment of nonaortic aneurysms in the endograft era: aneurysms of the innominate and subclavian arteries. Semin Vasc Surg. 18(4):184-90, 2005
                                                  11. Sueyoshi E et al: New development of an ulcerlike projection in aortic intramural hematoma: CT evaluation. Radiology 224: 536-41, 2002