Triple Rule Out CTA Scans or the Right Test for the Right Patient.

I n this issue of iJACC, Burris et al. (1) used a statewide registry to compare the diagnostic yield of coronary computed tomography angiography (CTA) with that of triple rule out (TRO) CTA scans and found that although there were slightly higher diagnostic yields for aortic dissection and pulmonary embolisms (PEs) in the TRO CTA group, this came at the cost of a higher dose of radiation and contrast exposure. This is the largest dataset to compare TRO CTA with coronary CTA and confirm the results of smaller studies and systematic reviews (2–5). However, as a comparative effectiveness study, the reader is unable to assess how clinicians decided which test to order or what institutional protocols existed. What disease or diseases were the clinicians trying to rule out? Why did they choose TRO CTA over a dedicated coronary CTA? Was it institutional protocol or provider choice? Furthermore, we do not know how many CTAs were done solely to evaluate for PE or aortic dissection.