Innominate Artery Blunt Trauma Donald J.
Magilligan, Jr, MD, Julio
Disruption
due to
C. Davila, MD
patients had innominate artery disruption due to blunt Compression forces between the sternum and vertebral column and rotational forces were the mechanisms of injury. Mediastinal widening led to the diagnosis in one patient who underwent successful repair with preservation of cerebral flow by an aortic to subclavian bypass graft prior to oversewing the innominate artery. A normal mediastinal shadow led to a delay in diagnosis in the second patient who underwent surgery after the appearance of focal neurologic signs. The use of a temporary indwelling aortic-carotid shunt during repair did not prevent residual hemiparesis. (Arch Surg 114:307-309, 1979) \s=b\ Two
rauma.
of the aorta occurs most often in the thoracic aorta and has been reported to occur in the more aorta in 10% of injuries to the aorta caused by blunt trauma.1 This report presents the
rupture Traumatic descending proximal
treatment of two recent cases of innominate artery disrup¬ tion due to blunt trauma with differing mechanisms of
subclavian artery. Blood flow through the innominate artery to the right carotid artery continued during the performance of these anastomoses. The distal innominate artery was then clamped and a side clamp was placed on the aortic arch at the take off of the innominate artery. The hematoma was entered and both ends were oversewn. Carotid circulation was preserved by flow through the graft into the subclavian artery shown on the postoperative arteriogram (Fig 2). The patient was well and working nine months after surgery. Case 2.—A 31-year-old woman was the driver of a small foreign car that struck a tree at high speed. She was not wearing a seat belt and was ejected through the windshield. The patient was examined at another hospital and was transferred four hours after injury because of the suggestion of widened mediastinum on a chest x-ray film. The patient complained of mild dyspnea, and on physical examination blood pressure and heart rate were normal and there were contusions and lacerations of the face, neck, and right anterior chest wall and subcutaneous emphysema. The right radial and carotid pulses were "decreased." Chest x-ray film showed a small right pneumothorax, fracture of the right second
injury, clinical presentations, routine roentgenographic and angiographie findings, and operative management. REPORT OF CASES
Case l.-A 47-year-old man sustained an injury to the right chest when he was crushed against a wall by a large truck. In the emergency room shortly thereafter, he complained of chest pain and shortness of breath. Physical examination revealed normal vital signs and equal pulses. There was a contusion of the right anterior portion of the chest wall and palpable fractures of the upper sternum and right second, third, and fourth costal carti¬ lages. Chest x-ray film showed a widened mediastinum (Fig 1) and arch aortography showed disruption of the innominate artery
(Fig 2). Through a midline sternotomy and right cervical extension, the
carotid and subclavian arteries were isolated and a hematoma surrounding the proximal innominate artery was left undisturbed. The pericardium was opened and a 12-mm Dacron graft was sutured to the ascending aorta and to the proximal common
for publication Sept 15, 1978. From the Division of Thoracic and Cardiac Surgery, Henry Ford Hospital, Detroit. Reprint requests to Division of Thoracic and Cardiac Surgery, Henry Ford Hospital, 2799 W Grand Blvd, Detroit, MI 48202 (Dr Magilligan).
Accepted
Fig 1.—Admission chest film in case 1 showing mediastinal widening indistinguishable from traumatic rupture of descending aorta.
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Fig 2—Case 1. Left, Preoperative aorto¬ gram showing typical hematoma and lucent line caused by intimai tear. Right, Postoperative aortogram showing aorticsubclavian bypass filling carotid, vertebral, and subclavian arteries.
vessel. The patient was hémiplégie on awakening from anesthesia and progressed satisfactorily with rehabilitation therapy. One year later the patient had slight improvement in motor function and a normal chest x-ray film.
COMMENT
Innominate artery disruption and acute traumatic disruption of the descending thoracic aorta have the same pathologic picture-intimal tear with a variable degree of
Fig 3.—Admission chest x-ray film in case 2 showing distinct lack of mediastinal widening in innominate or aortic arch area. rib, and subcutaneous and mediastinal emphysema. There was a small right pleural effusion and no substantial mediastinal widen¬ ing (Fig 3). Because of the lack of mediastinal enlargement, arteriography was delayed until 13 hours after injury, and at this time the patient began to exhibit left facial and arm weakness. Arch aortography showed complete occlusion of the right innomi¬ nate artery with filling of the subclavian artery by retrograde flow in the vetebral (Fig 4). The common carotid artery was not seen. Surgery was undertaken immediately, and the carotid and subclavian arteries were isolated through a sternotomy and right cervical extension. The distal innominate artery was pulseless and there was a hematoma at its origin. A temporary heparin-coated shunt was inserted from the ascending aorta to the common carotid artery. The innominate artery was resected and replaced with a 12-mm Dacron graft. Pathology showed dissection of the media by hemorrhage and intraluminal thrombus occluding the
thrombosis and hematoma contained by media or adventitia.1 Ten percent to 20 percent may survive long enough to be seen at a hospital.'*' The initial survivors will be at risk of rupture since the degree of fibroplasia in the adventitial wall is insufficient to prevent rupture for three months following injury.' Enlargement and delayed rupture can occur as can bacterial infection of a traumatic aneurysm.5 With innominate artery disruption, thrombosis with cerebral infarction constitutes an additional risk. The majority of innominate artery disruptions will occur in automobile accidents.'*3 Two mechanisms of injury have been postulated. First, the disruption may be due to a crush injury with entrapment of the innominate artery between the upper sternum and vertebral column." The second mechanism is a shearing force resulting from displacement of the heart into the left side of the chest and hyperextension of the cervical spine.7 The lap-shoulder seat belt has been implicated in the production of compression and torsion forces that result in innominate artery disruption." Case 1 exhibited simple direct compression as the mecha¬ nism of injury, while in case 2 it can be assumed a torsional force was a factor also since the patient was ejected from the car. Mediastinal widening seen on the plain chest x-ray film is usually the initial finding in innominate artery injury. The findings may be no different from aortic rupture at the isthmus, although there may be preservation of the outline of the descending aorta.1" The lack of mediastinal widening should not lead to a sense of security, since the chest x-ray film was initially normal for 28% of the patients with aortic
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Iowa User on 06/18/2015
K
Fig 4.—Aortograms in case 2. Patient was initially with unequal pulses, and left-sided weakness gradually evolved.
seen
There is total occlusion of innominate artery on early film (left). Later film (right) shows subclavian filling by retrograde flow in veterbral artery.
one series.11 In case 2 the normal mediastinal shadow led to a delay in diagnosis, but the magnitude of injury plus the pulse discrepancy should have led to earlier angiography and perhaps prevention of hemiparesis. The progression of innominate artery occlusion to hemi¬ paresis usually does not occur in young patients without coexisting cerebrovascular disease.12 The circle of Willis will ordinarily afford protection against extracranial occlu¬ sion of the carotid arteries.13 In addition, with innominate artery occlusion, retrograde flow in the vertebral will supply antegrade flow into the ipsilateral carotid.11 This "subclavian steal-carotid recovery phenomenon"'5 was seen on delayed films (Fig 4), and has not previously been reported in innominate artery injury due to blunt trauma to our knowledge. However, in case 2 these protective mechanisms were unable to provide sufficient blood flow to the right cerebral hemisphere. Because of the unpredictability of the effect of innomi¬ nate artery occlusion on cerebral circulation, most authors
rupture in
have recommended surgical repair with perfusion of the carotid artery on cardiopulmonary bypass" or with a temporary shunt.'" In case 2 a shunt was used; however, because of the evolving neurologic picture, the shunt was not effective in preventing hemiparesis. In case 1 neither carotid perfusion by bypass nor a shunt was used. However, carotid flow was preserved throughout surgery first through the damaged innominate artery while the aortic to subclavian bypass was constructed. Flow through the graft and then from subclavian to carotid provided permanent cerebral blood flow while the damaged innominate artery was clamped and oversewn. Such an approach has previously been described both for innominate artery disruption17 and for occlusive disease of the arch vessels,1" and is a safe way to effect repair while maintaining carotid flow. In those cases where the patho¬ logic anatomy dictates clamping the innominate artery, the distal carotid back pressure may be a valuable guide to determine the need for a temporary shunt."1
References 1. Parmley LF, Mattingly TW, Manion WC, et al: Nonpenetrating traumatic injury of the aorta. Circulation 17:1086-1101, 1958. 2. Heggtveit HA, Campbell JS, Hooper GD: Innominate arterial aneurysms occurring after blunt trauma. Am J Clin Pathol 42:69-74, 1964. 3. Greendyke RM: Traumatic rupture of the aorta. JAMA 195:527-530, 1966. 4. Bennett DE, Cherry JK: The natural history of traumatic aneurysms of the aorta. Surgery 61:516-523, 1967. 5. Stryker WA: Traumatic saccular aneurysm of the thoracic aorta. Am J Clin Pathol 18:152-161, 1948. 6. Bosher LH, Freed TA: The surgical treatment of traumatic rupture or avulsion of the innominate artery. J Thorac Cardiovasc Surg 54:732-739,
1967. 7. Binet JP, Langlois J, Cormier JM, et al: A case of recent traumatic avulsion of the innominate artery at its origin from the aortic arch. J Thorac Cardiovasc Surg 43:670-676, 1962. 8. Gunnlaugsson GH, Hallgrimsson JG, Sigurdsson JL, et al: Complete traumatic avulsion of the innominate artery from the aortic arch with a unique mechanism of injury. J Thorac Cardiovasc Surg 66:235-240, 1973. 9. Wexler L, Silverman J: Traumatic rupture of the innominate artery: A seat belt injury. N Engl J Med 282:1186-1187, 1970. 10. Eller JL, Ziter FMH Jr: Avulsion of the innominate artery from the aortic arch: An evaluation of roentgenographic findings. Radiology 94:75-78,
1970.
11. Applebaum A, Karp RB, Kirklin JW: Surgical treatment for closed thoracic aortic injuries. J Thorac Cardiovasc Surg 71:458-460, 1976. 12. Monson DO, Saletta JO, Freeark RJ: Carotid vertebral trauma. J Trauma 9:987-999, 1969. 13. Symonds C: The circle of Willis. Br Med J 1:119-124, 1955. 14. Mozersky DJ, Barnes RW, Sumner DS, et al: Hemodynamics of innominate artery occlusion. Ann Surg 178:123-127, 1973. 15. Killen DA, Gobbel WB: Subclavian steal-carotid recovery phenomenon. J Thorac Cardiovasc Surg 50:421-426, 1965. 16. Murray GF, Branley RK, Gott VL: Reconstruction of the innominate artery by means of a temporary heparin coated shunt bypass. J Thorac Cardiovasc Surg 62:34-41, 1971. 17. Franz JL, Simpson CR, Penny RM, et al: Avulsion of the innominate artery after blunt chest trauma. J Thorac Cardiovasc Surg 67:478-480, 1974. 18. DeBakey ME, Crawford ES, Morris GC Jr, et al: Surgical considerations of occlusive disease of the innominate, carotid, subclavian and vertebral arteries. Ann Surg 154:698-725, 1961. 19. Hays RJ, Levinson SA, Wylie EJ: Intraoperative measurement of carotid back pressure as a guide to operative management for carotid endo-arterectomy. Surgery 72:953-960, 1972.
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Iowa User on 06/18/2015
Magilligan, Jr, MD, Julio
Disruption
due to
C. Davila, MD
patients had innominate artery disruption due to blunt Compression forces between the sternum and vertebral column and rotational forces were the mechanisms of injury. Mediastinal widening led to the diagnosis in one patient who underwent successful repair with preservation of cerebral flow by an aortic to subclavian bypass graft prior to oversewing the innominate artery. A normal mediastinal shadow led to a delay in diagnosis in the second patient who underwent surgery after the appearance of focal neurologic signs. The use of a temporary indwelling aortic-carotid shunt during repair did not prevent residual hemiparesis. (Arch Surg 114:307-309, 1979) \s=b\ Two
rauma.
of the aorta occurs most often in the thoracic aorta and has been reported to occur in the more aorta in 10% of injuries to the aorta caused by blunt trauma.1 This report presents the
rupture Traumatic descending proximal
treatment of two recent cases of innominate artery disrup¬ tion due to blunt trauma with differing mechanisms of
subclavian artery. Blood flow through the innominate artery to the right carotid artery continued during the performance of these anastomoses. The distal innominate artery was then clamped and a side clamp was placed on the aortic arch at the take off of the innominate artery. The hematoma was entered and both ends were oversewn. Carotid circulation was preserved by flow through the graft into the subclavian artery shown on the postoperative arteriogram (Fig 2). The patient was well and working nine months after surgery. Case 2.—A 31-year-old woman was the driver of a small foreign car that struck a tree at high speed. She was not wearing a seat belt and was ejected through the windshield. The patient was examined at another hospital and was transferred four hours after injury because of the suggestion of widened mediastinum on a chest x-ray film. The patient complained of mild dyspnea, and on physical examination blood pressure and heart rate were normal and there were contusions and lacerations of the face, neck, and right anterior chest wall and subcutaneous emphysema. The right radial and carotid pulses were "decreased." Chest x-ray film showed a small right pneumothorax, fracture of the right second
injury, clinical presentations, routine roentgenographic and angiographie findings, and operative management. REPORT OF CASES
Case l.-A 47-year-old man sustained an injury to the right chest when he was crushed against a wall by a large truck. In the emergency room shortly thereafter, he complained of chest pain and shortness of breath. Physical examination revealed normal vital signs and equal pulses. There was a contusion of the right anterior portion of the chest wall and palpable fractures of the upper sternum and right second, third, and fourth costal carti¬ lages. Chest x-ray film showed a widened mediastinum (Fig 1) and arch aortography showed disruption of the innominate artery
(Fig 2). Through a midline sternotomy and right cervical extension, the
carotid and subclavian arteries were isolated and a hematoma surrounding the proximal innominate artery was left undisturbed. The pericardium was opened and a 12-mm Dacron graft was sutured to the ascending aorta and to the proximal common
for publication Sept 15, 1978. From the Division of Thoracic and Cardiac Surgery, Henry Ford Hospital, Detroit. Reprint requests to Division of Thoracic and Cardiac Surgery, Henry Ford Hospital, 2799 W Grand Blvd, Detroit, MI 48202 (Dr Magilligan).
Accepted
Fig 1.—Admission chest film in case 1 showing mediastinal widening indistinguishable from traumatic rupture of descending aorta.
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Iowa User on 06/18/2015
Fig 2—Case 1. Left, Preoperative aorto¬ gram showing typical hematoma and lucent line caused by intimai tear. Right, Postoperative aortogram showing aorticsubclavian bypass filling carotid, vertebral, and subclavian arteries.
vessel. The patient was hémiplégie on awakening from anesthesia and progressed satisfactorily with rehabilitation therapy. One year later the patient had slight improvement in motor function and a normal chest x-ray film.
COMMENT
Innominate artery disruption and acute traumatic disruption of the descending thoracic aorta have the same pathologic picture-intimal tear with a variable degree of
Fig 3.—Admission chest x-ray film in case 2 showing distinct lack of mediastinal widening in innominate or aortic arch area. rib, and subcutaneous and mediastinal emphysema. There was a small right pleural effusion and no substantial mediastinal widen¬ ing (Fig 3). Because of the lack of mediastinal enlargement, arteriography was delayed until 13 hours after injury, and at this time the patient began to exhibit left facial and arm weakness. Arch aortography showed complete occlusion of the right innomi¬ nate artery with filling of the subclavian artery by retrograde flow in the vetebral (Fig 4). The common carotid artery was not seen. Surgery was undertaken immediately, and the carotid and subclavian arteries were isolated through a sternotomy and right cervical extension. The distal innominate artery was pulseless and there was a hematoma at its origin. A temporary heparin-coated shunt was inserted from the ascending aorta to the common carotid artery. The innominate artery was resected and replaced with a 12-mm Dacron graft. Pathology showed dissection of the media by hemorrhage and intraluminal thrombus occluding the
thrombosis and hematoma contained by media or adventitia.1 Ten percent to 20 percent may survive long enough to be seen at a hospital.'*' The initial survivors will be at risk of rupture since the degree of fibroplasia in the adventitial wall is insufficient to prevent rupture for three months following injury.' Enlargement and delayed rupture can occur as can bacterial infection of a traumatic aneurysm.5 With innominate artery disruption, thrombosis with cerebral infarction constitutes an additional risk. The majority of innominate artery disruptions will occur in automobile accidents.'*3 Two mechanisms of injury have been postulated. First, the disruption may be due to a crush injury with entrapment of the innominate artery between the upper sternum and vertebral column." The second mechanism is a shearing force resulting from displacement of the heart into the left side of the chest and hyperextension of the cervical spine.7 The lap-shoulder seat belt has been implicated in the production of compression and torsion forces that result in innominate artery disruption." Case 1 exhibited simple direct compression as the mecha¬ nism of injury, while in case 2 it can be assumed a torsional force was a factor also since the patient was ejected from the car. Mediastinal widening seen on the plain chest x-ray film is usually the initial finding in innominate artery injury. The findings may be no different from aortic rupture at the isthmus, although there may be preservation of the outline of the descending aorta.1" The lack of mediastinal widening should not lead to a sense of security, since the chest x-ray film was initially normal for 28% of the patients with aortic
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Iowa User on 06/18/2015
K
Fig 4.—Aortograms in case 2. Patient was initially with unequal pulses, and left-sided weakness gradually evolved.
seen
There is total occlusion of innominate artery on early film (left). Later film (right) shows subclavian filling by retrograde flow in veterbral artery.
one series.11 In case 2 the normal mediastinal shadow led to a delay in diagnosis, but the magnitude of injury plus the pulse discrepancy should have led to earlier angiography and perhaps prevention of hemiparesis. The progression of innominate artery occlusion to hemi¬ paresis usually does not occur in young patients without coexisting cerebrovascular disease.12 The circle of Willis will ordinarily afford protection against extracranial occlu¬ sion of the carotid arteries.13 In addition, with innominate artery occlusion, retrograde flow in the vertebral will supply antegrade flow into the ipsilateral carotid.11 This "subclavian steal-carotid recovery phenomenon"'5 was seen on delayed films (Fig 4), and has not previously been reported in innominate artery injury due to blunt trauma to our knowledge. However, in case 2 these protective mechanisms were unable to provide sufficient blood flow to the right cerebral hemisphere. Because of the unpredictability of the effect of innomi¬ nate artery occlusion on cerebral circulation, most authors
rupture in
have recommended surgical repair with perfusion of the carotid artery on cardiopulmonary bypass" or with a temporary shunt.'" In case 2 a shunt was used; however, because of the evolving neurologic picture, the shunt was not effective in preventing hemiparesis. In case 1 neither carotid perfusion by bypass nor a shunt was used. However, carotid flow was preserved throughout surgery first through the damaged innominate artery while the aortic to subclavian bypass was constructed. Flow through the graft and then from subclavian to carotid provided permanent cerebral blood flow while the damaged innominate artery was clamped and oversewn. Such an approach has previously been described both for innominate artery disruption17 and for occlusive disease of the arch vessels,1" and is a safe way to effect repair while maintaining carotid flow. In those cases where the patho¬ logic anatomy dictates clamping the innominate artery, the distal carotid back pressure may be a valuable guide to determine the need for a temporary shunt."1
References 1. Parmley LF, Mattingly TW, Manion WC, et al: Nonpenetrating traumatic injury of the aorta. Circulation 17:1086-1101, 1958. 2. Heggtveit HA, Campbell JS, Hooper GD: Innominate arterial aneurysms occurring after blunt trauma. Am J Clin Pathol 42:69-74, 1964. 3. Greendyke RM: Traumatic rupture of the aorta. JAMA 195:527-530, 1966. 4. Bennett DE, Cherry JK: The natural history of traumatic aneurysms of the aorta. Surgery 61:516-523, 1967. 5. Stryker WA: Traumatic saccular aneurysm of the thoracic aorta. Am J Clin Pathol 18:152-161, 1948. 6. Bosher LH, Freed TA: The surgical treatment of traumatic rupture or avulsion of the innominate artery. J Thorac Cardiovasc Surg 54:732-739,
1967. 7. Binet JP, Langlois J, Cormier JM, et al: A case of recent traumatic avulsion of the innominate artery at its origin from the aortic arch. J Thorac Cardiovasc Surg 43:670-676, 1962. 8. Gunnlaugsson GH, Hallgrimsson JG, Sigurdsson JL, et al: Complete traumatic avulsion of the innominate artery from the aortic arch with a unique mechanism of injury. J Thorac Cardiovasc Surg 66:235-240, 1973. 9. Wexler L, Silverman J: Traumatic rupture of the innominate artery: A seat belt injury. N Engl J Med 282:1186-1187, 1970. 10. Eller JL, Ziter FMH Jr: Avulsion of the innominate artery from the aortic arch: An evaluation of roentgenographic findings. Radiology 94:75-78,
1970.
11. Applebaum A, Karp RB, Kirklin JW: Surgical treatment for closed thoracic aortic injuries. J Thorac Cardiovasc Surg 71:458-460, 1976. 12. Monson DO, Saletta JO, Freeark RJ: Carotid vertebral trauma. J Trauma 9:987-999, 1969. 13. Symonds C: The circle of Willis. Br Med J 1:119-124, 1955. 14. Mozersky DJ, Barnes RW, Sumner DS, et al: Hemodynamics of innominate artery occlusion. Ann Surg 178:123-127, 1973. 15. Killen DA, Gobbel WB: Subclavian steal-carotid recovery phenomenon. J Thorac Cardiovasc Surg 50:421-426, 1965. 16. Murray GF, Branley RK, Gott VL: Reconstruction of the innominate artery by means of a temporary heparin coated shunt bypass. J Thorac Cardiovasc Surg 62:34-41, 1971. 17. Franz JL, Simpson CR, Penny RM, et al: Avulsion of the innominate artery after blunt chest trauma. J Thorac Cardiovasc Surg 67:478-480, 1974. 18. DeBakey ME, Crawford ES, Morris GC Jr, et al: Surgical considerations of occlusive disease of the innominate, carotid, subclavian and vertebral arteries. Ann Surg 154:698-725, 1961. 19. Hays RJ, Levinson SA, Wylie EJ: Intraoperative measurement of carotid back pressure as a guide to operative management for carotid endo-arterectomy. Surgery 72:953-960, 1972.
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Iowa User on 06/18/2015
