Diagnosing Dissecting Aortic Aneurysm Klompas M: Does this patient have an acute thoracic aortic dissection? JAMA 2002; 287(17):2262-72.

This study's author identified and critically appraised 21 original investigations that described clinical findings for consecutive patients with confirmed thoracic aortic dissection. Most patients had severe pain (sensitivity 90%) and sudden onset (sensitivity 84%). On examination, 49% of patients had elevated blood pressure, 28% had a diastolic murmur, 17% had focal neurologic deficits, and 31% had pulse or blood pressure differences between body sides.

The plain chest x-ray is usually abnormal (sensitivity 90%). The presence of a normal aorta and mediastinum on the chest x-ray significantly decreases the probability of dissection (negative likelihood ratio 0.3) as does the absence of sudden pain onset (negative likelihood ratio 0.3). Although clinical cues can prompt recognition of aortic dissection, the clinical examination is insufficiently sensitive to rule it out.