Utility of gated ct angiography in diagnosis of aortic dissection: a case report

SESSION TITLE: Imaging the Unexpected SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/09/2023 02:10 pm - 02:55 pm INTRODUCTION: Ascending aortic dissection is a life-threatening condition that requires prompt diagnosis & management. CT angiography is considered the gold standard for diagnosis. Other diagnostic imaging modalities include chest X-ray, echocardiography, magnetic resonance imaging (MRI), and aortography. We present a case of pericardial effusion and tamponade found to have an aortic dissection on a transesophageal echocardiogram. CASE PRESENTATION: A 39-year-old male presented to the emergency department after experiencing a substernal popping sensation followed by complaints of shortness of breath and an episode of syncope during exertional activity. On presentation, the patient was tachycardia & had a pericardial rub. The results of blood work were unremarkable. A stat echocardiogram was performed, revealing a large 3.3 cm pericardial effusion with evidence of echographic findings of tamponade, including the right atrium and right ventricle collapse. CTA chest abdomen was negative for aortic dissection. Urgent pericardiocentesis was performed, draining 1100 ml of bloody fluid. The patient was admitted to the ICU and started on colchicine. Overnight the patient developed atrial flutter. A transesophageal echocardiogram (TEE) assisted cardioversion was planned. TEE revealed moderately dilated aortic root dilation measuring 4.9 cm, moderate aortic regurgitation, and ascending aortic dissection with false and true lumen starting distal to right and left main coronary arteries with exit immediately distal to the sinotubular junction. Cardioversion was canceled, and a gated CTA chest abdomen & pelvis was ordered that revealed a proximal ascending aortic Stanford type A DeBakey type II dissecting aneurysm. The patient underwent emergent aortic valve and ascending aorta replacement. DISCUSSION: A high index of suspicion is necessary for timely diagnosis and management of aortic dissection as delay is associated with worse prognosis. Ascending aortic dissection is a rare but serious condition that can present with a variety of symptoms. Pericardial effusion and tamponade are less commonly seen with aortic dissection. Gated CT imaging, which is synchronized with the cardiac cycle, provides better visualization of the cardiovascular structures compared to non-gated CT imaging. The management of aortic dissection involves medical management & surgical intervention. Emergent surgical intervention is indicated in cases of type A dissection. CONCLUSIONS: This case highlights the importance of various imaging modalities in the diagnosis of ascending aortic dissection. In our case, the TEE incidentally diagnosed the aortic dissection that was not seen on non-gated CTA. Hence, gated CT imaging is crucial in the timely diagnosis of ascending aortic dissection. REFERENCE #1: Nienaber CA, Clough RE. Management of acute aortic dissection. Lancet. 2015 Feb 28;385(9970):800-11. doi: 10.1016/S0140-6736(14)61005-9. Epub 2015 Feb 6. PMID: 25662791. REFERENCE #2: Hiratzka LF, Bakris GL, Beckman JA, Bersin RM, Carr VF, Casey DE Jr, Eagle KA, Hermann LK, Isselbacher EM, Kazerooni EA, Kouchoukos NT, Lytle BW, Milewicz DM, Reich DL, Sen S, Shinn JA, Svensson LG, Williams DM; American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines; American Association for Thoracic Surgery; American College of Radiology; American Stroke Association; Society of Cardiovascular Anesthesiologists; Society for Cardiovascular Angiography and Interventions; Society of Interventional Radiology; Society of Thoracic Surgeons; Society for Vascular Medicine. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with Thoracic Aortic Disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation. 2010 Apr 6;121(13):e266-369. doi: 10.1161/CIR.0b013e3181d4739e. Epub 2010 Mar 16. Erratum in: Circulation. 2010 Jul 27;122(4):e410. PMID: 20233780. DISCLOSURES: No relevant relationships by Mobeen Haider No relevant relationships by Yousra Khalid No relevant relationships by Muhammad Hasib Khalil No disclosure on file for Krishna Kurpad No relevant relationships by Zarlakhta Zamani