Estimation of serum levels of Lipoprotein(a) might help to resolve the dilemma of differentiation between Unstable Angina and Non-ST-elevation Myocardial Infarction

Abstract

Objectives: Evaluation of the performance of estimated serum levels of lipoprotein(a) [Lp(a)] and tissue plasminogen activator (t-PA) in the discrimination between patients presenting by cardiac events. Patients & Methods: 314 patients presenting with a clinical picture suggestive of an acute cardiac event (ACE) underwent clinical and laboratory workup according to the 2017 ESC Guidelines for the management of acute myocardial infarction (AMI). Blood samples were obtained for ELISA estimation of serum Lp(a) and plasma t-PA levels. Results: Clinically, 247 patients had angina, 166 stable angina (SA), 81 unstable angina (UA), 67 patients had AMI, 44 had non-ST-elevation MI (NSTEMI) and 23 patients had STEMI. Serum levels of Lp(a)were significantly higher in total patients' samples especially UA and MI patients compared to control samples, but were lower in those with compared to patients' samples. Further, Lp(a) levels were significantly higher in MI than UA patients' samples. Estimated t-PA levels were significantly higher in patients' than control samples, but were significantly higher in MI than angina patients' samples. Statistical analyses defined high estimated levels of Lp(a), t-PA, total cholesterol, and obesity as the significant differentiating variables between SA and UA patients and defined high levels of LP(a), t-PA, and obesity, and age as the significant predictors for NSTEMI. Conclusion: Elevated serum levels of Lp(a) might differentiate between UA patients and SA and NSTEMI with high specificity.