Benefits of pharmacological facilitation with glycoprotein IIb-IIIa inhibitors in diabetic patients undergoing primary angioplasty for STEMI. A subanalysis of the EGYPT cooperation

Impact of aging on platelet reactivity in diabetic patients receiving dual antiplatelet therapy

Advanced age and diabetes represent summative conditions in the determination of cardiovascular risk, and especially for the management of dual antiplatelet therapy (DAPT), often requiring balancing between bleeding and thrombotic complications. However, few studies have so far evaluated the impact of age on platelet reactivity and suboptimal platelet inhibition (high-on treatment platelet reactivity-HRPR) on DAPT among diabetic patients, that was, therefore the aim of the present study. In diabetic patients treated with DAPT (ASA + clopidogrel or ticagrelor) platelet reactivity was assessed at 30-90 days post-discharge for an acute coronary syndrome or elective PCI. Aggregation was assessed by multiple-electrode aggregometry. HRPR was defined for values above the lower limit of normality (in non-treated patients). Elderly patients were considered ≥ 75 years of age. We included 462 patients, among them 149 (32.2%) were ≥ 75 years. Elderly patients were more often females (p = 0.006), with lower body size (p = 0.04), acute coronary syndrome at presentation and renal failure (p < 0.001), non-smokers (p = 0.002), in therapy with insulin (p = 0.02) and diuretics (p < 0.001) and lower rate of betablockers (p = 0.02). Age directly related with C reactive protein (p = 0.01), creatinine levels and inversely with hemoglobin (p < 0.001) and triglycerides (p = 0.003). No association was found at linear regression analysis for platelet reactivity and age with different activating stimuli, but for ASPI test (r = 0.12; p = 0.03). No significant difference in HAPR was found in elderly patients (2.4 vs. 3.2%, p = 0.76, OR[95% CI] = 0.45[0.1-2.11], p = 0.31). HRPR for ADP antagonists was similarly not affected by age (30.1% vs. 35.7%, p = 0.28, adjusted OR[95% CI] = 0.78[0.47-1.29], p = 0.33). Comparable results were obtained when considering separately the DAPT strategies with clopidogrel or ticagrelor, or when adjusting our results according to propensity score values. Among diabetic patients receiving dual antiplatelet therapy for an acute coronary syndrome or elective percutaneous coronary intervention, age does not affect platelet reactivity or the rate of high-on treatment platelet reactivity. Similar results were obtained for ASA and clopidogrel or ticagrelor.

Relationship of thrombus characteristics to the incidence of angiographically visible distal embolization in patients with ST-segment elevation myocardial infarction treated with thrombus aspiration

OBJECTIVES

This study sought to investigate the association between pathological characteristics of aspirated intracoronary thrombi and the incidence of angiographically visible distal embolization (AVDE) during primary percutaneous coronary intervention (p-PCI) in patients with ST-segment elevation myocardial infarction (STEMI) treated with thrombus aspiration.

BACKGROUND

AVDE of atherosclerotic and thrombotic material has been shown to impair myocardial perfusion and contribute to poor clinical outcome in patients with STEMI. Recent studies have shown that thrombus composition and size are associated with the incidence of AVDE.

METHODS

Aspirated thrombi from 164 STEMI patients within 12 h of symptom onset were investigated immunohistochemically using antibodies against platelets, erythrocytes, and inflammatory cells.

RESULTS

The angiographic results showed that AVDE during p-PCI occurred in 22 (13.4%) patients. Pathological analysis revealed that thrombi from patients with AVDE had a greater erythrocyte-positive area (60 ± 15% vs. 43 ± 21%, p < 0.0005) and more myeloperoxidase-positive cells (943 ± 324 cells/mm(2) vs. 592 ± 419 cells/mm(2), p < 0.0005) than those from patients without AVDE. Thrombus size, quantified as the thrombus surface area, was positively correlated with the erythrocyte component (r = 0.362, p < 0.0001). Moreover, multivariate logistic analysis demonstrated that erythrocyte-positive area in the thrombi, glucose levels on admission, larger vessel diameter (≥ 3.5 mm), and pre-balloon dilation were independent predictors of the incidence of AVDE.

CONCLUSIONS

This study demonstrated that the erythrocyte-rich component of aspirated thrombi may be associated with the incidence of AVDE during p-PCI in patients with STEMI.

Impact of diabetes mellitus on the safety and effectiveness of bivalirudin in patients with acute myocardial infarction undergoing primary angioplasty: analysis from the HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial

OBJECTIVES

We sought to evaluate the safety and efficacy of bivalirudin compared with glycoprotein IIb/IIIa inhibitors (GPI) in diabetic patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

BACKGROUND

Prior studies have demonstrated that GPI are especially beneficial in patients with diabetes with acute coronary syndromes and/or those undergoing PCI.

METHODS

In the multicenter, prospective HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial, 3,602 patients with STEMI were randomized to bivalirudin or unfractionated heparin plus a GPI. Clinical outcomes were analyzed at 30 days and 1 year in patients with diabetes.

RESULTS

Diabetes mellitus was present in 593 patients (16.5%). The rates of cardiac death were significantly lower in diabetic patients treated with bivalirudin compared with heparin plus GPI (30 days: 2.1% vs. 5.5%, p = 0.04; 1 year: 2.5% vs. 7.1%, p = 0.01), and bivalirudin resulted in lower 30-day rates of stroke (0% vs. 2%, p = 0.02). There were no significant differences among diabetic patients randomized to bivalirudin versus heparin plus GPI in the 1-year rates of major adverse cardiac events (14.2% vs. 16.2%, p = 0.44), major bleeding (8.7% vs. 10.7%, p = 0.42), or stent thrombosis (4.2% vs. 3.8%, p = 0.85). By interaction testing, the relative effects of bivalirudin compared with heparin plus GPI were not significantly different in patients with and without diabetes.

CONCLUSIONS

In patients with diabetes mellitus presenting with STEMI undergoing primary PCI, anticoagulant therapy with bivalirudin compared with heparin plus GPI is safe and effective and might reduce cardiac mortality at 30 days and 1 year. (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).

Evaluation and management of special subgroups after primary percutaneous coronary intervention

In recent decades, the increased use of novel pharmacologic therapies and primary percutaneous coronary intervention has considerably improved survival in the setting of ST-segment elevation myocardial infarction. Nevertheless, optimal management and care of particular subgroups of patients such as the elderly and individuals with diabetes mellitus, renal dysfunction, or cardiogenic shock are still debated. In fact, because of their clinically relevant comorbidities, these patients are often excluded from randomized trials; thus, data are largely limited to those from retrospective cohorts or subgroup analyses of large clinical studies. These particular subgroups of patients require special management during and after prompt mechanical reperfusion because of their high risk of both thrombotic and bleeding events. Therefore, cardiologists should accurately assess the risk-benefit equation before administrating and dosing currently available antithrombotic and antiplatelets agents in these high-risk populations.