Age, Serum Creatinine, and Left Ventricular Ejection Fraction Improved the Performance of the CatLet Angiographic Scoring System in Terms of Outcome Predictions for Patients with Acute Myocardial Infarction: A Median 4.3-Year Follow-Up Study

Background: We recently developed the Coronary Artery Tree description and Lesion EvaluaTion (CatLet) angiographic scoring system. Our preliminary study demonstrated that the CatLet score better predicted clinical outcomes than the SYNTAX score. The current study aimed at assessing whether 3 clinical variables (CVs) - age, serum creatinine, and left ventricular ejection fraction (LVEF) - improved the performance of the CatLet score in outcome predictions in patients with acute myocardial infarction (AMI). Methods: This study was a post hoc study of the CatLet score validation trial. Primary endpoint was major adverse cardiac or cerebrovascular events (MACCEs), and secondary endpoints were all-cause deaths and cardiac deaths. Results: Over 1,185 person-years (median [interquartile range], 4.3 [3.8-4.9] years), there were 64 MACCEs (20.8%), 56 all-cause deaths (18.2%), and 47 cardiac deaths (15.2%). The addition of the 3 CVs to the stand-alone CatLet score significantly increased the Harrell's C-index by 0.0967 (p = 0.002) in MACCEs, by 0.1354 (p < 0.001) in all-cause deaths, and by 0.1187 (p = 0.001) in cardiac deaths. When compared with the stand-alone CatLet score, improved discrimination and better calibration led to a significantly refined risk stratification, particularly at the intermediate-risk category. Conclusions: CatLet score had a predicting value for clinical outcome in AMI patients. This predicting value can be improved through a combination with age, serum creatinine, and LVEF (http://www.chictr.org.cn; unique identifier: ChiCTR-POC-17013536).