Platelet PIA1/PIA2 polymorphism and the risk of periprocedural myocardial infarction in patients with acute coronary syndromes undergoing coronary angioplasty

Current and Future Roles of Glycoprotein IIb-IIIa Inhibitors in Primary Angioplasty for ST-Segment Elevation Myocardial Infarction

Acute myocardial infarction still represents the major cause of mortality in high-income countries. Therefore, considerable efforts have been focused on the treatment of myocardial infarctions in the acute and long-term phase, with special attention being paid to reperfusion strategies and adjunctive antithrombotic therapies. In fact, despite the successful mechanical recanalization of the epicardial conduit, a substantial percentage of patients still experience poor myocardial reperfusion or acute/subacute in-stent thrombosis. Due the delayed onset of action of currently available oral antiplatelet therapies, glycoprotein (GP) IIb-IIIa inhibitors could be expected to improve clinical outcomes, especially when administrated in the early phase of the infarction, due to the larger platelet composition of fresh thrombi, the dynamic nature of early thrombi, and the larger amount of viable myocardium existing in the early, as compared to a delayed, phase. Considerable evidence has accumulated regarding the benefits from GP IIb-IIIa inhibitors on mortality, especially among high-risk patients and when administered as an upstream strategy. Therefore, based on currently available data, GP IIb-IIIa inhibitors can be considered when the drug can be administered within the first 3 h of symptom onset and among high-risk patients (e.g., those with advanced Killip class or an anterior myocardial infarction). Even though it is not universally accepted, in our opinion, this strategy should be implemented in a pre-hospital setting (in an ambulance) or as soon as possible when arriving at the hospital (at the Emergency Room or Coronary Care Unit, irrespective of whether they are in spoke or hub hospitals). A new, second-generation GP IIb-IIIa inhibitor (zalunfiban) appears to be highly suitable as a pre-hospital pharmacological facilitation strategy at the time of first medical contact due to its favourable features, including its simple subcutaneous administration, rapid onset of action (15 min), and limited time of action (with a half-life of ~1 h), which is likely to minimize the risk of bleeding. The ongoing CELEBRATE trial, including 2499 STEMI patients, may potentially provide compelling data to support the upstream treatment of STEMI patients undergoing mechanical reperfusion. In fact, although the current therapeutic target of increased rates of timely reperfusion has been achieved, the future goal in myocardial infarction treatment should be to achieve the most rapid reperfusion prior to primary percutaneous coronary intervention, thus further minimizing myocardial damage, or, in some cases, even preventing it completely, and improving survival.

Relationship of non-cardiac biomarkers with periprocedural myocardial injury in patients undergoing percutaneous coronary intervention

percutaneous coronary intervention (PCI) is one of the dominant methods for revascularization in patient with coronary artery disease (CAD), which accompanied with high incidence of periprocedural myocardial injury (PMI) evaluated by postprocedural cardiac biomarker elevation. For the convenience of risk stratification of PMI following PCI, the aim of present review provides a unique opportunity to summarize the relationship of non-cardiac biomarkers with PMI by extensively searching in the MEDLINE to identify all the relevant studies. In conclusion, we found that PCI related PMI might be correlated positively to those non-cardiac biomarkers such as low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol, total cholesterol, triglyceride, the ratios of LDL-C to high-density lipoprotein cholesterol (HDL-C), the ratios of HDL-C to apolipoprotein A-I, the ratio of eicosapentaenoic acid to arachidonic acid, lectin-like oxidized low-density lipoprotein receptor-1, C-reactive protein, high on-treatment platelet reactivity, platelet-monocyte aggregates, N-term pro-B-type natriuretic peptide, hemoglobin and albuminuria. Inversely, no relationships of PMI with those non-cardiac biomarkers such as mean platelet volume, platelet distribution width, platelet-larger cell ratio, uric acid, eosinophils count and the genetic variant of methylenetetrahydrofolate reductase (MTHFR) 677 C>T polymorphism. Moreover, there were controversial associations between PMI and those non-cardiac biomarkers such as high-density lipoprotein cholesterol, glycosylated hemoglobin, homocysteine and the polymorphism Leu33Pro of platelet glycoprotein IIbIIIa. However, almost all studies failed to provide definite mechanism of its findings, and further reaches are needed to focus on the potential mechanisms of association between non-cardiac biomarkers and PMI related to PCI.

Relationship Between Glycoprotein IIIa Platelet Receptor Gene Polymorphism and Coronary Artery Disease

Glycoprotein IIb/IIIa (GP IIb/IIIa) is a key receptor for platelet aggregation and adhesion. We investigated whether a single-nucleotide polymorphism of GP IIIa subunit (Leu33Pro-PlA1/PlA2 allele) is associated with the extent of coronary artery disease (CAD) in a consecutive cohort of 1518 patients undergoing coronary angiography. Significant CAD was defined as at least a stenosis >50% and severe CAD as left main disease and/or trivessel disease. Additionally, carotid intima–media thickness (cIMT) was evaluated in 339 patients. The PlA2 allele was observed in 458 (30.2%) patients and associated with hypercholesterolemia ( P = .03). No difference was observed in the prevalence of CAD (72.6% vs 70.1%, P = .29; adjusted odds ratio, OR [95% confidence interval, CI] = 0.85 [0.67-1.08], P = .19) and severe CAD (27.5% vs 26.5%, adjusted OR [95% CI] = 0.93 [0.72-1.19], P = .55). Furthermore, Leu33Pro polymorphism did not affect cIMT and the prevalence of carotid plaques. Therefore, this polymorphism cannot be regarded as a risk factor for coronary or carotid atherosclerosis.

Platelet glycoprotein IIIa Leu33Pro gene polymorphism and coronary artery disease: A meta-analysis of cohort studies

Great interest has been focused in the last year on genetic predictors of cardiovascular risk. Glycoprotein IIb/IIIa (GP IIb/IIIa), fibrinogen receptor, is the final common pathway for aggregation and a key point for atherothrombosis. A single nucleotide polymorphism of IIIa subunit (Leu33Pro-PlA(1)/PlA(2) allele) has been suggested to increase aggregation and adhesion, however, contrasting reports have been reported so far on its effects on coronary artery disease (CAD). Aim of the current study was to perform a large meta-analysis including cohorts of patients undergoing coronary angiography in order to evaluate whether this polymorphism is associated with coronary artery disease. Literature archives (Pubmed, EMBASE, Cochrane) and main scientific sessions abstracts were scanned for data of consecutive cohorts of patients undergoing coronary angiography, where PlA genotype was assessed. Primary endpoint was the prevalence of CAD. Secondary endpoint was severity of CAD defined as prevalence of multivessel disease (≥2 vessels). Data from seven studies were extracted, including a final number of 6700 patients. Among them 1893 (28.3%) carried the PlA(2) polymorphism, 163 of them in homozygosis. Angiographically defined CAD was present in 3573 (74.3%) PlA(1)/PlA(1) patients and in 1430 (75.5%) PlA(2) carriers. PlA(2) polymorphism was not associated with an increased prevalence of coronary artery disease, (OR [95% CI] = 1.07 [0.95-1.21], p = 0.28, pheterogeneity = 0.39). Similar results were obtained for multivessel disease (OR [95% CI] = 1.07[0.95-1.20], p = 0.27, pheterogeneity = 0.12). Meta-regression analysis demonstrated a significant inverse relationship between the risk of CAD among the PlA(2) carriers and ageing (r = -0.044, (-0.09, -0.0008), p = 0.046). Present meta-analysis demonstrates that 33Leu → Pro substitution of GPIIIa does not influence the prevalence and extent of angiographically defined coronary artery disease in general population, although apparently playing a role among younger patients.