THORACOABDOMINAL AORTIC DISSECTION: ATYPICAL PRESENTATION AND MULTIORGAN DAMAGE

Abstract

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Acute Aortic Dissection (AoD) is the disruption of the tunica intima and tunica media of the aortic wall forming a blood-filled dissection plane dividing into "true" and "false" lumen. We categorize AoD as Type A and Type B (Stanford classification) based on the part of the aorta involved. However, an accurate diagnosis is difficult due to inconsistent clinical presentations (typically present with tearing chest pain radiating to the back). This is a unique clinical case of an atypical presentation with a complicated clinical course. CASE PRESENTATION: A 53-year-old man with untreated hypertension presented to the emergency room (ER) with worsening right lower extremity (RLE) pain and numbness for 6 days, aggravated with ambulation along with right lower quadrant (RLQ) abdominal pain. He endorses extensive tobacco, alcohol, marijuana, and cocaine use. In the ER, the blood pressure was 275/142 mmHg, biventricular hypertrophy on the EKG. He also had RLQ tenderness and diminished pulses in the RLE. The abdominal computed tomography (CT) discovered a distal abdominal aortic division. The larger false lumen dissected the left renal artery, left common iliac artery, with thrombosis of the left internal iliac artery. The narrow true lumen minimizes perfusion to the RLE and the right kidney. CT angiography of the chest confirmed a Stanford Type B aortic dissection with the intimal tear distal to the left subclavian artery. Intravenous Nicardipine and Esmolol drip controlled the blood pressure, followed by a femorofemoral bypass to improve RLE perfusion. Post-operative contrast nephropathy improved on day 10. Subsequently, a persistent ileus due to poor intestinal perfusion was corrected by transverse loop colostomy on day 15. On day 20, the patient was discharged with oral antihypertensive medications. DISCUSSION: The incidence of AoD is 5-30 per million people per year. 38% of ER presentations are missed; 28% are diagnosed at autopsy. Hypertension, atherosclerosis, cocaine abuse, cardiac surgeries, and systemic inflammatory syndromes can increase risk. Sullivan et al. suggest that a physician suspects AoD in 86% of patients with chest and back pain, 45% with only chest pain, and only 8% with abdominal pain. Our case is a unique combination of an atypical presentation (abdominal pain, leg numbness) with significant malperfusion of RLE, small bowel, and the right kidney (IRAD registry). For Type B dissection, medical management is preferred followed by surgical techniques to improve perfusion. Estimated inpatient mortality is 30% in proximal dissection and 10% in distal dissection. After the acute phase, the 10-year survival rate for AoD is <50%. CONCLUSIONS: Even with atypical symptoms, AoD and associated complications were successfully diagnosed and treated. Even with current surgical and medical advancements, controversies regarding diagnosis, the timing of repair, and type of repair still exist. REFERENCE #1: Cebicci, Huseyin & Salt, Omer & Gurbuz, Sukru & Sahin, Taner & Cumaoglu, Mustafa & Koyuncu, Serhat. (2014). Atypical presentations of aortic dissections: A case series. Acta Medica Mediterranea. 30. 85-90. REFERENCE #2: Sullivan PR, Wolfson AB, Leckey RD, Burke JL. Diagnosis of acute thoracic aortic dissection in the emergency department. Am J Emerg Med. 2000 Jan;18(1):46-50. doi: 10.1016/s0735- 6757(00)90047-0. PMID: 10674531 REFERENCE #3: Crawford, Todd C, et al. "Malperfusion Syndromes in Aortic Dissections." Vascular Medicine, vol. 21, no. 3, 2016, pp. 264–273., doi:10.1177/1358863x15625371 DISCLOSURES: No relevant relationships by Saurabh Chokshi, source=Web Response No relevant relationships by David Goldgrab, source=Web Response No relevant relationships by Devansh Patel, source=Web Response no disclosure on file for Jorge Perez