Q: 52 year old male presented to ER with chest pain radiating to back. Which one blood test may rule out Aortic dissection?

Answer:  Negative D-Dimer

A D-dimer <0.1 µg/mL will exclude Acute Aortic Dissection in all cases.

Reference:

D-dimer in ruling out acute aortic dissection: a systematic review and prospective cohort study - Eur Heart J (2007) 28 (24): 3067-3075.