Risk for Clinically Relevant Adverse Cardiac Events (CRACE) in very low risk chest pain patients admitted to hospital (in the USA)

Move over MACE and say hello to CRACE!

These high profile authors from the USA sought to determine the incidence of short term life threatening events in low risk chest pain patients admitted to hospital.

Their concern was a lack of benefit from admission balanced with the potential harm (false positives, over-diagnosis, hospital acquired infections, VTE, iatrogenic etc.).

They reviewed a large database from 3 hospitals in the US Midwest from 2008-2013. They identified admitted patients that had negative serial biomarkers (old school troponins), normal vital signs and non-ischemic ECGs.

Interestingly, these authors picked a different outcome measure for this study from the traditional MACE that we have seen in many previous studies. They created “CRACE” defined as:

• Life-threatening arrhythmia (VF, symptomatic bradycardia, or treated brady or tachy arrhythmias)
• Inpatient STEMI
• Cardiac or respiratory arrest
• Death

(Noticeably absent from CRACE is non-STEMI or longer term outcomes beyond hospitalization.)

What did they find?

Of course this group was very low risk… but could you have guessed a CRACE rate of only 0.06% (4 of 7266 patients)!

As is usually the case, there were some methodological issues with this study and the reported rate is probably not a complete reflection of the truth. However this makes a compelling argument that this is an extremely low risk group that may derive more net harm from admission.

The authors are careful to mention that this study does not mean patients derive no utility from further investigation and management after the ED evaluation. But suggest this may be done as an outpatient and might provide a framework for shared decision making.

My guess is the Australians would never admit many of these low risk patients anyway. In addition, these patients would be even lower risk with the high sensitive troponin assays.

Take home? Perhaps we can sleep a little better knowing that low risk patients truly are very low risk. Hope this doesn’t seem to CRACEy…

Covering:

Weinstock MB, Weingart S, Orth F, et al. Risk for Clinically Relevant Adverse Cardiac Events in Patients With Chest Pain at Hospital Admission. JAMA Intern Med. 2015;175(7):1207-1212.