Recurrent Transient Ischemic Attacks as the Initial Presenting Manifestation of Type A Aortic Dissection Osama O. Zaidat, MD, Eroboghene E. Ubogu, MD, and Alan J. Lerner, MD, Cleveland, Ohio A case is reported of an 84-year-old woman with recurrent episodes of aphasia and right-sided weakness with spontaneous complete resolution associated with hypotension. She subsequently developed lower gastrointestinal bleeding, ischemic toes, and anuria without associated chest pain. An emergent transesophageal echocardiography showed a type A aortic dissection with aortic valve insuf®ciency and tamponade. Emergent thoracotomy was performed, which con®rmed a severe acute type A aortic dissection. This is a reported case of acute painless aortic dissection presenting initially as recurrent transient ischemic attacks. The etiology of focal neurologic de®cits should be crucially determined by an experienced clinician prior to thrombolytic administration. This case illustrates the importance of aortic disease in the etiology of acute stroke syndromes. 1 Aortic artery diseases involving the ascending and the arch portion have been implicated in stroke, most commonly due to atherosclerotic disease and subsequent thromboembolization. Rarely has aortic dissection been implicated in the initial evaluation of cerebrovascular disease victims. Stroke occurs in about 3% of type A aortic dissection1 and less commonly as the initial presentation.2,3 Documented cases are accompanied by chest pain or hemodynamic instability, and neurological presentations include cerebral or spinal cord infarction, hypoxic encephalopathy, and ischemic neuropathy.4-6 A case is presented of a patient with recurrent transient ischemic attacks as an initial Department of Neurology, Case Western Reserve University School of Medicine, University Hospitals of Cleveland, Cleveland, OH. Correspondence to: O. O. Zaidat, MD, Neuroscience Critical Care Unit, University Hospitals of Cleveland, Department of Neurology, Hanna House, 5th Floor, Cleveland, OH 44106-5000, USA, E-mail: ooz@po.cwru.edu, eeubogu@excite.com. Ann Vasc Surg 2002; 16: 676-678 DOI: 10.1007/s10016-001-0193-6 Ó Annals of Vascular Surgery Inc. Published online: 26 August 2002 676 presentating manifestation of type A aortic artery dissection. This case stresses the importance of considering proximal aortic disease as an etiology of acute ischemic neurologic de®cits. CASE REPORT We present an 84-year-old right handed woman with a history of rheumatic heart disease with aortic valve stenosis, osteoarthritis, mild chronic renal insuf®ciency, and diverticulosis who experienced three episodes of transient aphasia and right-sided weakness in 2 hr. She denied any acute chest or back pain. Axial computerized tomography (CT) scan of the head was normal. Thrombolytics and anticoagulation were not administered, given her improving neurologic status. Physical examination revealed a blood pressure of 76/ 40 mmHg, heart rate of 80/min, a loud aortic end-diastolic murmur, and positive hemoccult stools without palpable rectal lesions. Neurological evaluation during an episode showed non¯uent aphasia and right hemiparesis involving mainly the face and arm that resolved completely within 10 min. Hemodynamic parameters were maintained and the patient was transferred to the neu- Vol. 16, No. 5, 2002 Case reports 677 DISCUSSION Fig. 1. Short-axis view of the ascending aorta by multiplane transesophageal echocardiogram showing a dissection intimal ¯ap separating the false and true lumens. roscience intensive care unit. Complete blood counts, coagulation pro®le, and serum metabolic panels were normal, and an electrocardiogram showed normal sinus rhythm with ®rst-degree atrioventricular and left bundle branch blocks. The initial posterioanterior plain chest radiograph was normal. Urgent carotid and transcranial Doppler ultrasonography showed no signs of critical stenosis or dissection. Ten hours later she developed cold, mottled toes with decreased lower extremity pulses bilaterally with lower gastrointestinal bleeding. A follow-up chest radiograph showed a widened mediastinum. Emergent transesophageal echocardiography (TEE) revealed an intimal tear in the ascending aorta above the aortic valve extending distally to the descending aorta as far as the limits of the TEE probe, consistent with a type A aortic dissection (Fig. 1). There was also evidence of severe aortic valve insuf®ciency, and mild pericardial effusion with pretamponade physiology. Abdominal ultrasonography showed the dissection extending to both iliac arteries. An emergent thoracotomy was performed within 12 hr of neurologic presentation. Intraoperatively, a large tear was found in the juxtasupravalvular position with dissection going along the ori®ces of the right and left coronary arteries. The dissection involved about 270° of the diameter of the aorta extending to the origin of the innominate artery. No dissection was noted at the origin of the carotid arteries. An aneurysmal component was present with maximum arterial diameter of 8 to 9 cm. The aortic dissection was repaired with a graft with concomitant aortic valve replacement. The patient had a complicated postoperative course, developed intractable heart and renal failure, and expired on postoperative day 4. With the introduction of tissue plasminogen activator in acute stroke care, timely and accurate diagnosis of focal neurologic de®cits is invaluable to avoid inadvertent use with possible lethal consequences.7 Painless aortic dissection has been reported in less than 10% of cases, and can create a diagnostic dilemma.5 Cerebral ischemia may be the presenting feature of aortic dissection,4-6 but the presence of other clinical signs and symptoms would direct clinicians to the diagnosis. Unusual aspects of this case include the lack of chest pain and the recurrent transient ischemic attacks in the anterior left middle cerebral artery distribution. Transient ischemic attacks have been rarely reported as the initial presenting manifestaion of aortic dissections, so its relationship to outcome is unknown. Different possible mechanisms have been entertained. Cerebral hypoperfusion due to hemodynamic compromise and subsequent watershed infarcts, diffuse generalized ischemia, or 2 focal infarct can occur if stenotic vascular disease is present intra- or extracranially.1-4,8 Acute occlusion or stenosis of common carotid artery by dissection extension, and artery-to-artery or cardiac embolization have also been implicated as a possible mechanisms1-4,8 In our patient, on the basis of the preoperative evaluation and intraoperative ®ndings, we believe that the most likely etiology is recurrent embolization, either cardiac or artery-toartery. Standard conventional angiography and, more recently, magnetic resonance angiography imaging are considered the gold standard for diagnosis, provided the patient is stable enough to undergo those procedures.9,10 Transesophageal echocardiography has an advantage of easy accessibility, can be done at the bedside even on critically ill patients, and allows for rapid cardiac function evaluation. Moreover, it provides accurate diagnosis with a sensitivity of 100% and speci®city of 98%.10 Conventional angiography was not performed in our patient because of the acute renal failure and hemodynamic instability. Noninvasive diagnostic tools were utilized rapidly to provide a diagnosis and aid in decision making in this case. The poor outcome in this case was probably not related to the initial neurologic presentation, but the severity of the type A aortic dissection. The mortality rate is variable, but as a general rule, it increases with extent and severity of the dissection, and with time. The mortality rate may range between an average of 13% within the ®rst 12 hr to 74% in the ®rst 2 weeks, and may be reduced by 678 Case reports early surgical intervention with cerebral perfusion.8,11,12 Intraoperative mortality may be associated with impaired renal function, hypertension, older age, hemodynamic shock, aortic rupture, and cardiac tamponade.8,11 Hospital mortality may occur in up to 25.9% of patients undergoing surgical treatment for acute type A aortic dissection under deep hypothermic circulatory arrest, and may be related to lack of cerebral perfusion intraoperatively and postoperative renal failure.12 CONCLUSION This case emphasizes the importance of ascertaining the etiology of ®xed or transient acute ischemic neurologic de®cits by an experienced clinician prior to instituting appropriate therapy. A high index of suspicion for aortic dissection is necessary in patients with focal neurologic de®cits associated with hemodynamic instability and other symptoms compatible with acute arterial insuf®ciency. Early surgical intervention utilizing cerebral perfusion and deep hypothermic circulatory arrest may reduce mortality. Proper use of noninvasive diagnostic tools may be vital in elucidating the etiology and directing prompt management in atypical cases of transient ischemic attacks. REFERENCES 1. Fann JI, Sarris GE, Mitchell RS, et al. Treatment of patients with aortic dissection presenting with peripheral vascular complications. Ann Surg 1990;212:705-713. Annals of Vascular Surgery 2. Veyssier-Belot C, Cohen A, Rougemont D, Levy C, Amerenco P, Bousser MG. Cerebral infarction due to painless thoracic aortic and common carotid artery dissections. Stroke 1993;24:2111-2113. 3. Lynch DR, Dawson TM, Raps EC, Galetta SL. Risk factors for the neurologic complications associated with aortic aneurysms. Arch Neurol 1992;49:284-288. 4. Fann JI, Starris GE, Miller DC, et al. Surgical treatment of acute aortic dissection complicated by stroke. Circulation 1989;80:1257-1263. 5. De Sanctis RW, Doroghazi RM, Austen WG, Buckley MJ. Aortic dissection. N Engl J Med 1987;317:1060-1067. 6. Blanco M, Diez-Tejedor E, Larrea JL, Ramirez U. Neurologic complications of type I aortic dissection. Acta Neurol Scand 1999;99:232-235. 7. The National Institute of Neurologic Disorders and Stroke r-TPA Stroke Study Group. Tissue plasminogen activator for acute ischemic stroke. N Engl J Med 1995;333:15811586. 8. Cambria RP, Brewster DC, Gertler J, et al. Vascular complications associated with spontaneous aortic dissection. J Vasc Surg 1988;7:199-209. 9. Goldman AP, Kotler MN, Scanlon MH, Ostrum B, Parameswaran R, Parry WR. The complementary role of magnetic resonance imaging, Doppler echocardiography, and computed tomography in the diagnosis of dissecting thoracic aneurysms. Am Heart J 1986;111:970-981. 10. Erbel R, Mohr-Kahaly S, Oelert H, et al. Diagnosis strategies in suspected aortic dissection: comparison of computed tomography, aortography, and transesophageal echocardiography. Am J Cardiac Imaging 1990;4:157-172. 11. Hirst AE, Johns VJ, Kime SW. Dissecting aneurysm of the aorta: a review of 505 cases. Medicine 1958;37:217279. 12. Sinatra R, Melina G, Pulitani I, Fiorani B, Ruvolo G, Marino B. Emergency operation for acute type A aortic dissection: neurologic complications and early mortality. Ann Thorac Surg 2001;71:33-38.