Tue JOURNAL OF TRAUMA Copyright © 1977 by The Williams & Wilkins Co. Vol. 17, No. 12 Printed in U.S.A. TRAUMATIC ANEURYSM OF THE INTRATHORACIC LEFT CAROTID ARTERY WITH CEREBRAL EMBOLIZATION JOE A. PINKERTON, Jr., M.D., EDWIN E. MacGEE, M.D., ann K.G. ROMINE, M.D. From the Department of Surgery, Truman Medical Center and the U1 niversity of Missouri at Kansas City School of Medicine, and St. Luke’s Hospital of Kansas City, Kansas City, Missouri The presentation and management of a young male patient with a traumatic aneurysm of the intrathoracic portion of the left common carotid artery from a football injury, compli- cated by cerebral embolization, is detailed. At operation 6 weeks afterward the aneurysm was isolated and ligated and the patient was discharged 19 days postoperation with plans for physical and speech rehabilitation. At 14 months a chronic subdural hematoma which caused some seizures was removed, and the patient’s neurologic status is continuing to improve. This appears to be the first report of an isolated blunt injury to this branch of the aortic arch. Blunt injury of the thoracic aorta and its brachiocephalic branches is a well recognized consequence of violent trauma. Acute hemor- rhage is the usual result of this injury, but it may present on a delayed basis as a false aneurysm which may enlarge, rupture, or re- sult in embolization. This paper discusses the course and management of a patient with a traumatic aneurysm of the intrathoracic por- tion of the left. carotid artery complicated by cerebral embolization. CASE REPORT A 23-year-old male was examined in the emer- gency room of Kansas City General Hospital follow- ing blunt trauma to the left shoulder and neck incurred while playing football. Clinical and radio- logic examination of this patient, including X-rays of the cervical spine and clavicle appeared normal. The symptoms were pain and soreness in the local area. The patient returned 5 days later with a 12- hour history of severe left-sided headaches and a 4- hour history of right hemiparesis, aphasia, and bladder and anal incontinence. He was found to be lethargic, with a bruit audible over the base of the neck on the left side, and right hemiplegia, with right homonymous hemianopia. Evaluation at the time of admission included a chest X-ray which appeared normal, and arteriog- raphy which demonstrated a false aneurysm of the left carotid artery approximately 2 cm distal to its origin from the aortic arch (Fig. 1). An intimal flap was evident in the distal portion of this aneurysm, apparently the result of a traumatic tear of the left Address for reprints: Joe A. Pinkerton, Jr., M._D., 4320 Wornall Road, Kansas City, MO 64111. 975 carotid artery (Fig. 2). The left middle cerebral artery was occluded intracranially from what ap- peared to be an embolus from the traumatic aneu- rysm in the proximal left carotid artery. The aortic arch and other brachiocephalic vessels were normal, with no other evidence of injury to these vessels. The patient was initially anticoagulated with Coumadin (Endo) for 10 days* and given Decadron (Merck, Sharpe & Dohme) for one week. Definitive surgical treatment of the traumatic aneurysm was deferred for 6 weeks because of the completed stroke which had occurred. Minimal evidence of neurologic improvement was noted during this period. At operation a median sternotomy with proximal extension into the neck along the anterior border of the left sternocleidomastoid muscle was used for the surgical approach to this traumatic aneurysm. Initially, a ligature was passed around the proximal left carotid artery which was later to be ligated. A 10-mm preclotted knitted Dacron graft was anasto- mosed end-to-side to the ascending aorta. The left common carotid artery was transected distal to the traumatic aneurysm and anastomosed end-to-end to the Dacron graft. The proximal end of the tran- sected left carotid artery was oversewn and the previously placed silk ligature tied securely proxi- mal to the traumatic aneurysm. This isolated the aneurysm without requiring dissection or removal of the aneurysm itself. Systemic heparinization was employed during the arterial reconstruction. Pros- taphlin (Bristol) was given prophylactically for 4 * The use of anticoagulants here can certainly be argued because while it is not usually indicated in acute stroke, according to many it is the treatment of choice in embolization, and one must make the decision as to whether the risk of using anticoagu- lants is greater or less than the risk of not using them (Eds.). 976 Fic. 1. Arch aortogram demonstrating the false aneurysm of the left carotid artery. days postoperatively. Mediastinal drainage tubes were removed 48 hours postoperatively. No neuro- logic deterioration could be detected in the postop- erative course which was uneventful and uncompli- cated. The patient was discharged on the 19th post- operative day with plans for continued rehabilita- tion and speech therapy. The patient's long term postoperative course has demonstrated slow, continued neurologic improve- ment. Approximately 14 months postoperatively, he began having seizures and was found to have an area of intracranial calcification over the frontal portion of the left cerebral hemisphere. Arteriog- raphy and computerized tomography demonstrated a chronic subdural hematoma in this area, whereas there had been no evidence of a subdural hematoma in the patient's initial clinical picture. Arteriog- raphy demonstrated patency of the arterial recon- struction. The chronic subdural hematoma was re- moved through a left frontal craniotomy. The pa- tient’s neurologic status continues to improve slowly. DISCUSSION Traumatic tear of the thoracic aorta and its major branches is associated with such a high acute mortality that the majority of the pa- tients with this injury fail to reach the emer- gency room with hope of survival (6). The THE JOURNAL OF TRAUMA, December 1977 Fic. 2. Selective arteriogram of the left common carotid artery demonstrating the false aneurysm and the prolapsing torn distal edge of the vessel wall. gravity of this injury has led to an acute aware- ness of its occurrence in major trauma centers. The diagnosis in a stable patient is predicated on a high degree of suspicion, widening of the mediastinum or hemothorax on chest X-ray, and abnormal brachiocephalic pulses or neuro- logic symptoms unrelated to head trauma. Aor- tography establishes the diagnosis definitively and demonstrates the location and extent of the injury. Tear of the major intrathoracic vessels without clinical or chest X-ray evidence to suggest such an injury is rare, although it has been reported (2). Isolated blunt injury to the brachiocephalic branches of the thoracic aorta occur less commonly, and the risk of exsanguination before hospital arrival is not clearly defined (2). Trauma violent enough to tear these major vessels is usually associated with injuries to other structures. The absence of any clinical or radiographic evidence of vas- cular injury and the absence of associated inju- ries resulted in a delay in the diagnosis of intrathoracic vascular injury in our patient. This patient may represent the first case Vol. 17, No. 12. | TRAUMATIC LEFT CAROTID ANEURYSM WITH EMBOLIZATION reported with isolated blunt injury to the intra- thoracic left carotid artery. Castagna and Nel- son (2) in 1974 published an excellent review of blunt injuries to branches of the aortic arch. They found 36 patients with 40 vascular inju- ries. Their review and a review of the subse- quent English-language literature did not pro- duce a report of a similar blunt injury to this branch of the aortic arch. Blunt injury to the cervical portion of the carotid artery has been reported by many au- thors (3-5, 9, 10), but this injury occurs much less frequently than carotid arterial injuries associated with penetrating trauma to the neck (9, 10). Blunt injury to the cervical portion of the carotid artery is often overlooked initially only to have the patient suddenly develop hem- iplegia after a lucid interval which may be as short as a few hours or as long as 2 weeks (4). The diagnosis of blunt injury to the carotid may be obscured by the absence of any evidence of injury or by the presence of extensive associ- ated injuries. The mechanism of injury is re- lated to disruption of the wall of the artery, which may involve only the intima, producing a roughened focus which may be the source of emboli or complete thrombosis of the artery (3, 5). The tear may involve the media and result in either thrombosis of the artery or the forma- tion of a false aneurysm, as occurred in our patient. Both intimal and medial tears may result in prolapse of the torn distal edge of the vessel wall, as seen in Figure 2. Aneurysms of the extracranial carotid artery have the potential for rupture, thrombosis, and embolization. Only 42 patients had reportedly undergone surgical reconstruction after resec- tion of a carotid artery aneurysm in an English- language literature review published in 1972 by Rittenhouse (7). Traumatic aneurysms have been reported much less frequently than true aneurysms of the carotid artery (8). The surgical approach to blunt injury of the carotid artery varies with the time of recogni- tion and clinical state of the patient. Injuries recognized acutely and in the absence of neu- rologic deficit should be repaired promptly. Acute repair of carotid artery injuries in the presence of neurologic deficit is associated with increased mortality (10). A delayed presenta- tion associated with a major neurologic deficit and a stabilized clinical state warrants a delay 977 of 4 to 6 weeks, in keeping with the accepted approach to atherosclerotic occlusive disease of the carotid artery (10). The surgical approach to the intrathoracic portion of the left carotid artery for manage- ment of traumatic injuries or aneurysmal changes may present a technical challenge. A median sternotomy with a cervical extension was chosen in our patient as the best single exposure to provide simultaneous proximal and distal contro] and allow reconstruction of the left carotid artery. Other surgical approaches which could be considered include reflection of a flap of the left anterior chest wall for exposure of the left carotid artery, or separate cervical and left thoracotomy incisions, as described by Brawley (10). Other methods of reconstruction of the left carotid artery which may be feasible include direct anastomosis of the left carotid artery to the left subclavian or a similar recon- struction with an interposed Dacron or vein graft. REFERENCES 1. BRawLEY RK, Murray GF, Crisuer C et al: Management of wounds of the innominate, sub- clavian, and axillary blood vessels. Surg Gyne- col Obstet 131:1130, 1970 2. Castacna J, Netson RJ: Blunt injuries to branches of the aortic arch. J Thorac Cardiovasc Surg 69:521, 1975 3. Crissy MM, Bernstein EF: Delayed presenta- tion of carotid intimal tear following blunt cran- iocervical trauma. Surgery 75:543, 1974 4. JERNIGAN WR, Garpner WC: Carotid artery injuries due to closed cervical trauma. J Trauma 11:429, 1971 5. McGoucu EC, Hetrrich LR, Hucues RK: Traumatic intimal prolapse of the common ca- rotid artery. Am J Surg 123:724, 1972 6. RirrenHouse EA, Dittarp DH, WINTERSCHIED LC et al: Traumatic rupture of the thoracic aorta: A review of the literature and a report of five cases with attention to special problems in early surgical management. Ann Surg 170:87, 1969 7. Rirrenyouse EA, Rapke HM, Sumner DS: Ca- rotid artery aneurysm. Arch Surg 10§:786, 1972 8. Roprnson NA, Frorre CT: Traumatic aneu- rysms of the carotid arteries. Am Surg 40:121, 1974 9. Rusio PA, Reut GJ, Bratt AC et al: Acute carotid artery injury: 25 years’ experience. J Trauma 14:967, 1974 10. THat ER, Snyper WH, Hayes RJ et al: Manage- ment of carotid artery injuries. Surgery 76:955, 1974