Residual coronary artery tree description and lesion EvaluaTion (CatLet) score, clinical variables, and their associations with outcome predictions in patients with acute myocardial infarction

Abstract

Background: We have recently developed a new Coronary Artery Tree description and Lesion EvaluaTion (CatLet) angiographic scoring system. Our preliminary studies have demonstrated its superiority over the the Synergy between percutaneous coronary intervention (PCI) with Taxus and Cardiac Surgery (SYNTAX) score with respect to outcome predictions for acute myocardial infarction (AMI) patients. The current study hypothesized that the residual CatLet (rCatLet) score predicts clinical outcomes for AMI patients and that a combination with the three clinical variables (CVs)-age, creatinine, and ejection fraction, will enhance its predicting values.

Methods: The rCatLet score was calculated retrospectively in 308 consecutively enrolled patients with AMI. Primary endpoint, major adverse cardiac or cerebrovascular events (MACCE) including all-cause mortality, non-fatal AMI, transient ischemic attack/stroke, and ischemia-driven repeat revascularization, was stratified according to rCatLet score tertiles: rCatLet_low ≤3, rCatLet_mid 4-11, and rCatLet_top ≥12, respectively. Cross-validation confirmed a reasonably good agreement between the observed and predicted risks.

Results: Of 308 patients analyzed, the rates of MACCE, all-cause death, and cardiac death were 20.8%, 18.2%, and 15.3%, respectively. Kaplan-Meier curves for all endpoints showed increasing outcome events with the increasing tertiles of the rCatLet score, with P values <0.001 on trend test. For MACCE, all-cause death, and cardiac death, the area under the curves (AUCs) of the rCatLet score were 0.70 (95% confidence intervals [CI]: 0.63-0.78), 0.69 (95% CI: 0.61-0.77), and 0.71 (95% CI: 0.63-0.79), respectively; the AUCs of the CVs-adjusted rCatLet score models were 0.83 (95% CI: 0.78-0.89), 0.87 (95% CI: 0.82-0.92), and 0.89 (95% CI: 0.84-0.94), respectively. The performance of CVs-adjusted rCatLet score was significantly better than the stand-alone rCatLet score in terms of outcome predictions.

Conclusion: The rCatLet score has a predicting value for clinical outcomes for AMI patients and the incorporation of the three CVs into the rCatLet score will enhance its predicting ability.

Trial registration: http://www.chictr.org.cn , ChiCTR-POC-17013536.

Figure 1

Flow chart of patient selection. AMI: Acute myocardial infarction; CAG: Coronary angiography; CatLet: Coronary Artery Tree description and Lesion EvaluaTion; MI: Myocardial infarction; rCatLet: Residual CatLet.

Figure 2

KM curves for MACCEs (A), all-cause death (B), and cardiac death (C) at 4.3 years according to the rCatLet score tertiles. CatLet: Coronary artery tree description and lesion EvaluaTion; KM: Kaplan–Meier; MACCE: Major adverse cardiovascular and cerebrovascular events; rCatLet: Residual CatLet; rCatLet_low, rCatLet_mid, and rCatLet_top: Low, mid, and top tertile of rCatLet score, respectively.

Figure 3

The ROC curves revealed significant differences between rCatLet score and adjusted rCatLet score for predicting MACCEs (A), all-cause death (B), and cardiac death (C) at 4.3 years. Adj-rCS: Adjusted residual CatLet score; AUC: Area under the curve; CatLet: Coronary artery tree description and lesion EvaluaTion; MACCE: Major adverse cardiovascular and cerebrovascular event; rCatLet: Residual CatLet; rCS: Residual CatLet score; ROC: Receiver operating characteristic.

Figure 4

Calibration plots of rCatLet score and adjusted rCatLet score at cross-validation with respect to clinical outcomes for rCatLet score (A–C) and adjusted rCatLet score (D–F), respectively. The circle indicates the observed frequencies by tertile of predicted probabilities with a 95% CI. Good agreement was found between the observed and predicted incidence for all endpoints. Intercept also called CITL. A lowess smoothing curve was added to each calibration plot. Intercept of 0 and slope of 1 indicate perfect prediction. AUC: Area under the curve; CatLet: Coronary artery tree description and lesion EvaluaTion; CI: Confidence interval; CITL: Calibration-in-the-large; E:O: Estimation risk/observed risk; MACCE: Major adverse cardiovascular and cerebrovascular event; rCatLet: Residual CatLet.

Figure 5

HRs for MACCE per 1 unit higher CatLet score stratified by risk factors, dichotomously or medially, adjusted for age, serum creatinine, and LVEF. For smoking and drinking, "Yes" indicated current smoking or drinking, and "No" indicated never or past smoking or drinking. Black squares represent point estimates and error bars, 95% CI. CatLet: Coronary artery tree description and lesion EvaluaTion; CI: Confidence interval; HDL-C: High density lipoprotein cholesterol; HR: Hazard ratio; LAD: Left anterior descending artery; LCX: Left circumflex coronary artery; LDL-C: Low-density lipoprotein cholesterol; LVEF: Left ventricular ejection fraction; MACCE: Major adverse cardiovascular and cerebrovascular event; PDA: Posterior descending artery; RCA: Right coronary artery; rCatLet: Residual CatLet; rCatLet_low, rCatLet_mid, and rCatLet_top: Low, mid, and top tertile of rCatLet score, respectively; STEMI: ST-segment elevation myocardial infarction; TC: Total cholesterol; TG: Triglycerides.