Scope of Application
This guideline is intended for physicians working in emergency departments.

Inclusion Criteria
This guideline is intended for adult patients aged 18 years and older presenting to the ED with suspected acute nontraumatic thoracic aortic dissection.

Exclusion Criteria
This guideline is not intended to be used for patients with traumatic aortic dissection, pediatric patients, or pregnant patients.

Critical Questions

1. In adult patients with suspected acute nontraumatic thoracic aortic dissection, are there clinical decision rules that identify a group of patients at very low risk for the diagnosis of thoracic aortic dissection?
   
   Level C Recommendations:
   
   In an attempt to identify patients at very low risk for acute nontraumatic thoracic aortic dissection, do not use existing clinical decision rules alone. The decision to pursue further workup for acute nontraumatic aortic dissection should be at the discretion of the treating physician.
   
   
   
2. In adult patients with suspected acute nontraumatic thoracic aortic dissection, is a negative serum D-dimer sufficient to identify a group of patients at very low risk for the diagnosis of thoracic aortic dissection?
   
   Level C Recommendations:
   
   In adult patients with suspected nontraumatic thoracic aortic dissection, do not rely on D-dimer alone to exclude the diagnosis of aortic dissection.
   
   
   
3. In adult patients with suspected acute nontraumatic thoracic aortic dissection, is the diagnostic accuracy of computed tomography angiogram (CTA) at least equivalent to transesophageal echocardiogram (TEE) or magnetic resonance angiogram (MRA) to exclude the diagnosis of thoracic aortic dissection?
   
   Level B Recommendations:
   
   In adult patients with suspected nontraumatic thoracic aortic dissection, emergency physicians may use CTA to exclude thoracic aortic dissection because it has an accuracy similar to that of TEE and MRA.
   
   
   
4. In adult patients with suspected acute nontraumatic thoracic aortic dissection, does an abnormal bedside transthoracic echocardiogram (TTE) establish the diagnosis of thoracic aortic dissection?
   
   Level B Recommendations:
   
   In adult patients with suspected nontraumatic thoracic aortic dissection, do not rely on an abnormal bedside TTE result to definitively establish the diagnosis of thoracic aortic dissection.
   
   Level C Recommendations:
   
   In adult patients with suspected nontraumatic thoracic aortic dissection, immediate surgical consultation or transfer to a higher level of care should be considered if a TTE is suggestive of aortic dissection. (Consensus recommendation)
   
   
   
5. In adult patients with acute nontraumatic thoracic aortic dissection, does targeted heart rate and blood pressure-lowering reduce morbidity or mortality?
   
   Level C Recommendations:
   
   In adult patients with acute nontraumatic thoracic aortic dissection, decrease blood pressure and pulse if elevated. However, there are no specific targets that have demonstrated a reduction in morbidity and mortality.
   
   

Disclaimer
Recommendations offered in this policy are not intended to represent the only diagnostic and management options that the emergency physician should consider. ACEP recognizes the importance of the individual physician's judgment and patient preferences.