Prognostic implications of calculated Apo-lipoprotein B in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: Outcome is tied to lower cut-points.

Background: Debates still surround using lipoproteins including Apo-B in risk assessment, management, and prognosis of patients with coronary artery disease. During an acute ST-segment elevation myocardial infarction, Apo-B might help to achieve incremental prognostic information.

Objective: We sought to determine the potential prognostic utility of calculated Apo-B in a cohort of patients with STEMI undergoing primary PCI.

Methods: A retrospective cohort study was conducted enrolling 2,259 patients with a diagnosis of acute STEMI who underwent primary PCI. Apo-B was obtained using a valid equation based on initial lipid measurements. High Apo-B was defined as a level of 65 or higher. Primary endpoint of the study was major adverse cardiovascular events (MACE).

Results: Mean age of the participants was 59.54 years and 77.9% of them were male. After a Median follow up of 15 (6.2) months, high Apo-B was associated with MACE and the OR (95% CI) was 3.02 (1.07-8.47), p = .036. Odds ratios for prediction of MACE pertaining to LVEF, and smoking were 0.97 (p = .044), and 1.07 (p = .033), respectively. However, High Apo-B was not able to predict suboptimal TIMI flow. Accordingly, the Odds ratio was 0.56 (0.17-1.87), p = 0.349. The power of High LDL-C and Non-HDLC for prediction of MACE were assessed in distinct models. Attained odds ratios were [2.40 (0.90-6.36), p = .077] and [1.80 (0.75-4.35), p = 0.191], respectively.

Conclusion: Calculated Apo-B appears to be a simple tool applicable for prediction of cardiovascular events in patients with STEMI superior to both Non-HDLC and LDL-C.