MR angiography can guide ED management of suspected acute aortic dissection.

BACKGROUND: Aortic dissection is typically evaluated with computed tomography angiography (CTA). However, the feasibility of using magnetic resonance angiography (MRA) in the ED is unclear. This study examined the indications and outcomes of MRA in suspected aortic dissection evaluation in the ED. METHODS: An IRB approved review identified patients who underwent MRA in the ED for acute thoracic aortic dissection from January 2010 to June 2016. Demographics, clinical assessment, CTA contraindications, outcomes, and ED disposition were analyzed. RESULTS: 50 MRAs were ordered for suspected thoracic aortic dissection. 21 (42%) for iodinated contrast allergy, 21 (42%) for renal insufficiency, 2 (4%) due to both, 2 (4%) to spare ionizing radiation, 2 (4%) for further work-up after CTA, and 2 (4%) due to prior contrast enhanced CT within 24h. Median ED arrival to MRA completion time was 311min. 42 studies were fully diagnostic; 7 were limited. One patient could not tolerate the examination. 49 MRAs were completed: 2 (4%) patients had acute dissection on MRA and 47 (96%) had negative exams. 17 (35%) received gadolinium. 18 (37%) patients were discharged home from the ED with a median length of stay of 643min. 2 (4%) were admitted for acute dissection seen on MRA and 29 (59%) for further evaluation. CONCLUSION: MRA has a clear role in the evaluation for acute thoracic aortic dissection in the ED in patients with contraindications to CTA, and can guide management and facilitate safe discharge to home.