Case Report

A case report of Stanford type A aortic dissection presenting with status epilepticus

Abstract

Acute aortic dissection is a rapidly fatal condition that may present atypically with focal Neurologic manifestations. We report a case of Stanford type A aortic dissection presenting with status epilepticus. This Unusual presentation posed an initial diagnostic challenge to the managing physicians. We further emphasize the need to be aware of the diagnostic difficulties in this condition and that early recognition with prompt surgical intervention is imperative in reducing significant morbidity and mortality.

Acute aortic dissection presents classically with acute onset tearing chest pain, mediastinal widening on chest radiograph, or a differential pulse volume or blood pressure between extremities. However, 10% of cases may present atypically with focal neurologic manifestations; and this may hinder diagnosis and prompt management of this rapidly fatal condition. As acute aortic dissection is a surgical emergency with an extremely high mortality rate, early recognition of these atypical presentations is crucial [1-3].

A 66-year-old Chinese man presented to the emergency department (ED) with status epilepticus. He was watching a television program when his wife noticed that he was diaphoretic and subsequently lost consciousness. A brief period of jerking movements involving the left upper limb that spontaneously aborted was observed. En route to the hospital, another similar episode was observed. His signif- icant medical history included hypertension and a stroke with residual mild left hemiparesis. He had been well before presentation. On arrival, he was afebrile with a blood pressure of 100/43 mm Hg, heart rate of 45 beats per minute, and peripheral oxygen saturation of 95% on venturi mask 35% and had normal capillary blood glucose level. His Glasgow coma scale was 6 (E1V1M4). Neurologic exam- ination revealed sluggish pupils with bilateral lower limb hypertonicity and upgoing plantar reflexes. Results of other examinations were unremarkable. Initial laboratory investi- gations and electrocardiogram (ECG) were within normal limits. An urgent computed tomography of the brain showed no acute intracranial hemorrhage or infarction. The Initial diagnosis was status epilepticus secondary to scar epilepsy

from a previous nonhemorrhagic infarct. He was admitted to the Neurology high dependency unit for observation after being administered intravenous pHenytoin in the ED.

However, upon arrival in the High Dependency Unit, he developed refractory severe hypotension, bradycardia, and hypoxia requiring mechanical ventilation and inotropic support. An urgent ECG showed new deep ST-segment depressions in the inferolateral leads. An urgent coronary angiography revealed an aortic root dissection with possible compression of the left main coronary artery. A computed tomographic aortography revealed a Stanford A aortic dissection from the root of the aorta to 3 cm from the bifurcation, with extension into the right brachiocephalic trunk, right common carotid, Superior mesenteric artery, and left renal artery (Fig. 1). An urgent cardiothoracic surgical consult was obtained, but emergency Aortic repair was held off. This patient had previously indicated that he did not want to be subjected to heroic measures should any untoward circumstances befall him. The patient was transferred to the Cardiothoracic Intensive Care Unit where he was supported for the next 12 hours before passing away.

Acute aortic dissection is a potentially fatal condition that requires early recognition and prompt intervention. Ninety- six percent of cases of aortic dissection presents classically with sudden severe tearing chest pain. However, more than

Fig. 1 Computed tomographic aortography revealing a Stanford A aortic dissection.

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243.e6 Case Report

10% of cases may present atypically with focal neurologic deficits [2]. These symptoms are often dramatic and may dominate the clinical picture, masking the underlying condition [4].

The Stanford classification divides aortic dissection into 2 types: type A, involving the Ascending aorta, and type B, involving only the aorta distal to the origin of the left subclavian artery. Type A is most commonly associated with neurologic presentations, either secondary to extension of dissection into the common Carotid arteries, through thromboembolism, or Cerebral hypoperfusion. The most common neurologic manifestation is ischemic stroke, predominantly right sided, although Altered consciousness and seizures may present at or soon after the onset of aortic dissection [1,3].

In this case report, we demonstrate the difficulty in diagnosing aortic dissection that presented atypically with status epilepticus. This resulted in an inappropriate admis- sion to the neurologic unit. This was further compounded by the development of acute ST-segment depressions in the inferolateral leads on the ECG, which could have led to inappropriate treatment with high-dose antiplatelets and anticoagulants, as for a non-ST-elevation myocardial infarction [5,6]. We postulate that the sudden onset of symptoms heralded the beginning stages of the aortic dissection, with the left upper limb seizures resulting from dissection into the right carotid artery and the persistent loss of consciousness from global cerebral hypoperfusion. The left coronary artery compression manifested by means of the dynamic ECG changes that were misinterpreted as an acute ischemic event. The involvement of the abdominal aortic branches was missed clinically given the comatose state of the patient.

In conclusion, we recommend that aortic dissection be considered in Hypertensive patients presenting with status epilepticus, particularly if there is no antecedent history of seizures. The clinical suspicion of aortic dissection must also be heightened when 2 or more vascular territories are

involved. Routine check of all peripheral pulses and measurement of blood pressure from both arms, aside from chest radiography, in all patients presenting with focal neurologic deficits should be done, especially when a detailed clinical history cannot be obtained. All physicians should maintain a High clinical index of suspicion, as early diagnosis of this potentially Catastrophic condition can be lifesaving [1-4].

Jolene E.L. Oon MBBCh Adrian C.L. Kee MBBS Department of Medicine National University Hospital Singapore 119074, Singapore

E-mail address: [email protected]

Hong Chuen Toh MBBS Department of Emergency Medicine National University Hospital Singapore 119074, Singapore

doi:10.1016/j.ajem.2010.03.011

References

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