Doctor: I saw you were in the Emergency Room the other day…

Patient: Oh yeah me and Uncle Willy got a little carried away with a couple of ropes and a pitchfork… thought maybe I had busted my spleen or exploded my liver, but they said everything looked good and sent me home!

Doctor: Glad your spleen is ok…did they mention anything about all the plaque around your heart?

Patient: Huh?

You all are intimately familiar with the “Got Plaque? Get a CAC!” screening strategy as the “Colonoscopy of the Heart…Without the Nasty Pregame Show.”  This type of screening CAC is called a “gated” scan and is synchronized to the cardiac cycle; the thought is that this provides the best image clarity.  But it’s important to also look for INCIDENTAL CAC on non-specific, non-gated CT scans that were originally obtained for some reason other than coronary plaque detection. And THIS STUDY from the MESA BioBank showed that those with CAC on non-gated CT scans had between 2.5 and 8.5 times greater risk of major adverse cardiovascular events than those with no detectable plaque!  Additionally, the ~2500 folks in this study had both gated and non-gated scans, and the results were quite comparable regardless of whether you were a Gater Gator or not.

Here are the Highlights:

• Those with MODERATE CAC (corresponding to a score of 101-299) on non-gated CT had a 2.67x risk of coronary heart disease (CHD).
• Those with SEVERE CAC (corresponding to a score of >300) on non-gated CT had a 5.22x risk of CHD.
• Additionally, those NOT ON STATINS had a 2.85x risk of CHD if non-gated CT showed even MILD plaque (corresponding to CAC 1-99).  This increased to 5.02x with MODERATE plaque and a whopping 8.97x risk of CHD for the SEVERE CAC group. 
  • Interestingly, these values were 2.33, 2.38, and 8.58 in this non-statin group for mild, moderate, and severe CAC, respectively, by gated scans, so future in-depth comparisons will be helpful in analyzing the discordant results, particularly in that “moderate CAC” group.
  • I have some additional questions that I have emailed the authors regarding those who had zero CAC on gated scans AND simultaneously CAC>0 on non-gated (and vice versa), so stay tuned for that as well!

But the key takeaway here is that looking for incidental CAC on non-specific, non-gated CT scans is a GREAT IDEA.  It’s so obvious that even the 2026 Cholesterol Guidelines recommends it!

It’s sort of like in Pediatrics when a sick kid comes in puking, fevering, and snotting all over the treatment room.  Might as well do a Rapid Strep swab while they’re here!  And if it’s positive for strep, you treat it, even though they may not have come in with a chief complaint of sore throat.  Similarly, if you’ve got plaque in your coronaries (even if we were originally looking for a tumor or that pitchfork tine that Willy stuck near your spleen), then you probably ought to do something about it rather than just “hope for the best.”