Inttermitent convulsive syncope as initial presentation in painless acute type a circumferential aortic dissection

We report a case of a 36 yo male with hypertension history who is sent to ER with suspected seizure attack. 3 hours before the patient started to feel dizziness and unsteadiness and consciousness loss, seizure attack and esfincter relaxation were noted 2 times. At arrival had severe hypotension (68/34 mmHg). The EKG and brain CT were unremarkable. Troponines were negative. After started with chest pain. As an unstable patient an transthoracic echocardiogram was performed, showing left ventricle hypertrophy, with circunferential flap affecting aortic valve who suffered severe insufficiency. To ensure diagnosis and great vessels affectation also so planning the surgical intervention a thoracoabdominal CT wihout an with contrast was performed. CT shows type A Acute Aortic Disection (AAD) with circunferential intimal flap who extended from Valsalva Sinus to proximal section of descending thoracic aorta (posterior to Left Subclavian Artery). The flap affected also the most proximal section of brachiocephalic artery and dissected totally the Left Common Carotid Artery. Left subclavian artery arised from the true lumen. The rest of thoracic aorta and abdominal aorta were undamaged. The CT also showed basal bilateral pulmonary infiltrates due to congestive heart failure. Surgeons decided urgent surgical repair but the patient went to asystolia and death before intervention.

AAD is an emergency and often resulting in the death of the patient, with type A AAD can occur secondary to acute aortic regurgitation, major aortic branch obstruction, pericardial tamponade, or aortic rupture, (most common into the pericardium). The initial presenting symptoms and signs of AAD are so diverse that it makes early and accurate diagnosis arduous. Painless and convulsive syncope are atypical presentations of AAD. Neurologic symptoms as initial presenting manifestation of AAD account for approximate 5-20% of patients, most common are stroke, neuropathy,syncope , somnolence and seizures. This can include involvement of one or more main arterial branch vessels so it is important to include them in the scanning rango to ensure early diagnosis and aid in surgical planning to improve prognosis so CTimaging of the aorta is fast and widely available in unstable patients. A circumferential intimal flap is an uncommon flap and occurs due to dissection of the entire intima. Intima usually tears near the coronary orifices and inner lumen is usually the true lumen.

Atypical presentations of AAD make promptly accurate diagnosis difficult, especially in painless AAD who have higher morbidity than painful AAD patients. CT imaging is essential in diagnosis quickly in unstable and aid surgical planning.

- Park SW, Hutchison S, Mehta RH, et al.Association of painless acute aortic dissection with increased mortality.Mayo Clin Proc 2004,79:1252–7. - Michelle A. McMahon and Christopher A. Squirrell. Multidetector CT of Aortic Dissection: A Pictorial Review.