CRAX: A simple cardiovascular risk assessment tool to predict risk of acute myocardial infarction or death

Area of Science:

• Cardiology
• Medical Imaging
• Risk Assessment

Background:

• Optimizing patient management requires accurate determination of cardiovascular event risk.
• Myocardial perfusion imaging (MPI) is a key diagnostic tool in cardiology.
• Predicting major adverse cardiac events (MACE) is crucial for clinical decision-making.

Purpose of the Study:

• To develop and validate the CRAX tool for predicting the cumulative risk of death and acute myocardial infarction (AMI).
• To assess the predictive accuracy of the CRAX tool compared to clinical variables and MPI results alone.
• To evaluate the CRAX tool's performance in predicting major adverse cardiac events (MACE).

Main Methods:

• 5842 individuals underwent SPECT MPI with a mean follow-up of 4.4 years.
• The CRAX tool was developed using clinical and MPI variables to predict 1, 3, and 5-year risks of death and AMI.
• Predictors included age, prior hospitalizations, left ventricular ejection fraction (LVEF), pharmacological stress use, global stress total perfusion deficit (sTPD), transient ischemic dilation (TID), and ischemic total perfusion deficit (iTPD) change.

Main Results:

• CRAX predictions were significantly more accurate (P < .001) than clinical variables or MPI alone.
• The tool demonstrated significant net reclassification improvement (NRI) of 7.5% for AMI and 14.5% for death.
• Accuracy for predicting MACE was comparable to that for AMI or death.

Conclusions:

• The CRAX tool is an effective risk assessment tool for predicting AMI, death, and MACE.
• CRAX significantly improves risk prediction compared to using clinical variables or MPI results independently.
• The tool enhances the ability to optimize patient management through more accurate risk stratification.