The net clinical benefit of personalized antiplatelet therapy in patients undergoing percutaneous coronary intervention.

This was a prospective study comparing two groups: personalized and non-personalized treatment with P2Y12 receptor blockers during a 12-month follow-up. We aimed to investigate whether personalized antiplatelet treatment in patients with high on-treatment platelet reactivity (HTPR) improves clinical outcome. Platelet reactivity was assessed by adenosine diphosphate induced aggregation using a multiple electrode aggregometry (MEA) in 798 patients with coronary artery disease undergoing percutaneous coronary intervention (PCI). Patients with HTPR received up to four repeated loading doses of clopidogrel or prasugrel in the personalized treatment group (n=403), whereas no change in the treatment strategy was undertaken in patients with HTPR in the non-personalized treatment group (n=395). There were fewer major adverse cardiac events (MACE) in the personalized treatment group than in the non-personalized treatment group (7.4% compared with 15.3% respectively; P<0.001). The multivariate Cox regression analysis showed that the relative risk to develop MACE was 51% lower in the personalized treatment group as compared with the non-personalized treatment group [hazard ratio (HR)=0.49; 95% confidence interval (CI): 0.31-0.77; P<0.001]. Similarly, there was a clear net benefit of the personalized antiplatelet treatment over the non-personalized treatment (ischemic and bleedings events: 8.2% versus 18.7% respectively; HR=0.46; 95%CI: 0.29-0.70; P<0.001). Further analysis indicated that patients with aggregation values within the therapeutic window (21-49 units) experienced the lowest event rates (stent thrombosis and major bleeding: 2.5%) as compared with poor responders (≥50 units: 5.4%) or ultra-responders (0-20 units: 5.2%). In conclusion, personalized antiplatelet treatment might improve patients' outcome without increasing bleeding complications compared with the non-personalized treatment during a 12-month follow-up.

Individualising dual antiplatelet therapy after percutaneous coronary intervention: the IDEAL-PCI registry.

OBJECTIVE: To evaluate the clinical utility of individualising dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in an all-comers population, including ST-elevation myocardial infarction (STEMI) patients. SETTING: Tertiary care single centre registry. PARTICIPANTS: 1008 consecutive PCI patients with stent implantation, without exclusion criteria. INTERVENTION: Peri-interventional individualisation of DAPT, guided by multiple electrode aggregometry (MEA), to overcome high on-treatment platelet reactivity (HPR) to ADP-induced (≥50 U) and arachidonic acid (AA)-induced aggregation (>35 U). OUTCOME MEASURES: The primary efficacy end point was definite stent thrombosis (ST) at 30 days. The primary safety end point was thrombolysis in myocardial infarction (TIMI) major and minor bleeding. Secondary end points were probable ST, myocardial infarction, cardiovascular death and the combined end point: major cardiac adverse event (MACE). RESULTS: 53% of patients presented with acute coronary syndrome (9% STEMI, 44% non-ST-elevation). HPR to ADP after 600 mg clopidogrel loading occurred in 30% of patients (73±19 U vs 28±11 U; p<0.001) and was treated by prasugrel or ticagrelor (73%), or clopidogrel (27%) reloading (22±12 U; p<0.001). HPR to ADP after prasugrel loading occurred in 2% of patients (82±26 U vs 19±10 U; p<0.001) and was treated with ticagrelor (34±15 U; p=0.02). HPR to AA occurred in 9% of patients with a significant higher proportion in patients with HPR to ADP (22% vs 4%, p<0.001) and was treated with aspirin reloading. Definite ST occurred in 0.09% of patients (n=1); probable ST, myocardial infarction, cardiovascular death and MACE occurred in 0.19% (n=2), 0.09% (n=1) and 1.8% (n=18) of patients. TIMI major and minor bleeding did not differ between patients without HPR and individualised patients (2.6% for both). CONCLUSIONS: Individualisation of DAPT with MEA minimises early thrombotic events in an all-comers PCI population to an unreported degree without increasing bleeding. A randomised multicentre trial utilising MEA seems warranted. TRIAL REGISTRATION NUMBER: http://www.clinicaltrials.gov; NCT01515345.

Platelet inhibition by abciximab bolus-only administration and oral ADP receptor antagonist loading in acute coronary syndrome patients: the blocking and bridging strategy.

INTRODUCTION: Current guidelines still recommend the bolus and infusion administration of glycoprotein IIbIIIa inhibitors in patients with high-risk acute coronary syndrome undergoing percutaneous coronary intervention. We sought to evaluate the extent of platelet inhibition by a blocking and bridging strategy with intracoronary abciximab bolus-only administration and oral loading of adenosine diphosphate receptor antagonists. PATIENTS AND METHODS: Fifty-six consecutive high-risk acute coronary syndrome patients with bolus-only abciximab administration (0.25 mg/kg i.c.) and loading with 600 mg clopidogrel (55%) or 60 mg prasugrel (45%) were included in this study. Platelet aggregation induced by thrombin receptor-activating peptide and adenosine diphosphate was measured by multiple electrode aggregometry up to 7 days. RESULTS: Thrombin receptor-activating peptide induced platelet aggregation was significantly suppressed for a minimum of 48 h (45±17U) and returned to a normal range (>84 U) after 6 days (90±26U; p<0.001). Co-medication with prasugrel significantly reduced adenosine diphosphate-induced (p=0.002) and thrombin receptor-activating peptide-induced (p=0.02) platelet aggregation compared with clopidogrel throughout the observation period. No stent thrombosis or repeat myocardial infarction occurred at 30-day follow-up. CONCLUSIONS: Immediate blocking of platelet aggregation in high-risk acute coronary syndrome patients by intracoronary abciximab bolus-only administration and bridging to prolonged inhibition via oral blockade of ADP receptors effectively inhibited overall platelet reactivity for at least 48 h, questioning the value of continuous abciximab infusion. Co-medication with prasugrel vs. clopidogrel synergistically augmented platelet inhibition.

Personalized antiplatelet treatment after percutaneous coronary intervention: the MADONNA study.

BACKGROUND AND OBJECTIVES: Clopidogrel non-responsiveness is associated with adverse clinical outcome. We aimed to investigate whether individualized antiplatelet treatment in clopidogrel non-responders is an effective and safe strategy. METHODS: This was a prospective non-randomized non-blinded study comparing two cohorts (guided and non-guided treatment) with a follow-up of 1-month. Responsiveness to clopidogrel was assessed by multiple electrode aggregometry (MEA) in 798 patients with coronary artery disease undergoing percutaneous coronary intervention (PCI). In the guided group (n=403) clopidogrel non-responders received repeated loading doses of clopidogrel or prasugrel, in the non-guided group (n=395) clopidogrel non-responders did not undergo any change in treatment. RESULTS: Stent thrombosis occurred significantly less often in the guided group than in the non-guided group (0.2% vs. 1.9%; p=0.027). The multivariate Cox regression analysis showed that patients in the non-guided group were at a 7.9-fold higher risk to develop stent thrombosis compared to the guided group (OR: 7.9; 95% CI: 1.08-69.2; p=0.048). In line with this, acute coronary syndrome occurred significantly less often in the guided group than in the non-guided group (0% vs. 2.5%; p=0.001) whereas there was no difference in the event rates of cardiac death (2% vs. 1.3%; p=0.422) or major bleedings (1% vs. 0.3%; p=0.186). CONCLUSION: Personalized antiplatelet treatment according to the platelet function testing with MEA resulted in an improved efficacy with an equal safety compared to the standard treatment.

Duplex sonography versus angiography for assessment of femoropopliteal arterial disease in a "real-world" setting.

PURPOSE: To evaluate the agreement of duplex ultrasound (DUS) versus digital subtraction angiography (DSA) for assessment of femoropopliteal arterial disease in a real-world clinical setting. METHODS: Consecutive patients with peripheral artery disease who were scheduled for a percutaneous intervention were included in this retrospective study. During an 18-month period, 491 patients (276 men; median age 73 years, interquartile range 64-81) were enrolled. A peak systolic velocity ratio (PSVR)>2.4 was the optimal cutoff for detecting a >50% stenosis by DSA. Findings of preprocedural DUS in the proximal, middle, and distal ipsilateral superficial femoral artery and in the popliteal segment were analyzed for agreement with preprocedural femoropopliteal DSA using kappa statistics. Only the target limb in each patient was analyzed, for a total of 1964 vascular segments. RESULTS: Agreement for the degree of stenosis in 10% increments was only moderate (weighted kappa 0.67, 95% CI 0.65 to 0.69). Using the PSVR>2.4 cutoff, agreement between DUS and DSA for a >50% stenosis was good (kappa 0.79, 95% CI 0.77 to 0.81). Sensitivity, specificity, positive predictive value, and negative predictive value for correctly detecting a >50% stenosis by DUS were 0.81 (0.78 to 0.84), 0.93 (0.91 to 0.94), 0.84 (0.81 to 0.87), and 0.91 (0.87 to 0.95), respectively. Comparable findings were observed within different patient subgroups. CONCLUSION: Agreement between DUS and DSA in the femoropopliteal segment is only moderate with respect to the absolute degree of stenosis. However, detection of a >50% stenosis can be done with acceptable precision in routine clinical practice using PSVR>2.4 as a threshold.