Dual Antiplatelet Therapy with 3rd Generation P2Y12 Inhibitors in STEMI Patients: Impact of Body Mass Index on Loading Dose-Response.

PURPOSE: This study aims to assess the association between body mass index (BMI) and platelet reactivity in STEMI patients treated with oral 3rd generation P2Y12 inhibitors. METHODS: Overall, 429 STEMI patients were enrolled in this study. Patients were divided into two groups according to BMI (BMI < 25 vs ≥ 25 kg/m2). A propensity score matching (1:1) was performed to balance potential confounders in patient baseline characteristics. Platelet reactivity was assessed by VerifyNow at baseline and after 3rd generation P2Y12 inhibitor (ticagrelor or prasugrel) loading dose (LD). Blood samples were obtained at baseline (T0), 1 h (T1), 2 h (T2), 4-6 h (T3), and 8-12 h (T4) after the LD. High on-treatment platelet reactivity (HTPR) was defined as a platelet reactivity unit value ≥ 208 units. RESULTS: After propensity score matching, patients with BMI ≥ 25 had similar values of baseline platelet reactivity, while they had higher level of platelet reactivity at 1 and 2 h after the LD and higher rate of HRPT. Furthermore, multivariate analysis demonstrated that BMI ≥ 25 was an independent predictor of HTPR at 2 h (OR 2.01, p = .009). Conversely, starting from 4 h after the LD, platelet reactivity values and HRPT rates were comparable among the two study groups. CONCLUSIONS: A BMI ≥ 25 kg/m2 is associated with delayed pharmacodynamic response to oral 3rd generation P2Y12 inhibitor LD, and it is a strong predictor of HTPR in STEMI patients treated by dual antiplatelet therapy with ticagrelor or prasugrel.

Not-high before-treatment platelet reactivity in patients with STEMI: prevalence, clinical characteristics, response to therapy and outcomes.

Platelet reactivity (PR) has been indicated as a pathophysiological key element for ST-Elevation Myocardial Infarction (STEMI) development. Patients with not-high before-treatment platelet reactivity (NHPR) have been poorly studied so far. The aim of this study is to investigate the prevalence, clinical characteristics, response to therapy and outcomes of baseline prior to treatment NHPR among patients with STEMI undergoing primary PCI.We analyzed the data from 358 STEMI patients with assessment of PR by VerifyNow before P2Y12 inhibitor loading dose (LD). Blood samples were obtained at baseline, and after 1 hour, 2 hours, 4-6 hours and 8-12 hours after LD. High platelet reactivity (HPR) was defined as Platelet Reactivity Unit values ≥208, while patients with values <208 at baseline were defined as having NHPR.Overall, 20% patients had NHPR. Age and male gender both resulted independent predictors of NHPR, even after propensity score adjustment. The percentage of inhibition of PR after ticagrelor or prasugrel LD was similar between HPR and NHPR patients at each time point. However, patients with HPR showed worse in-hospital clinical outcomes, and the composite adverse outcome endpoint of death, reinfarction, stroke, acute kidney injury or heart failure was significantly higher (10.0% vs 1.4%; p = .017) as compared with the NHPR group.In conclusion, a significant proportion of patients presenting with STEMI has a baseline NHPR that is associated with better in-hospital outcomes as compared with patients with HPR. Further studies are needed to better elucidate the potential therapeutic implications of NHPR in terms of secondary prevention.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) update 2022.

Primary Percutaneous Coronary Intervention (PCI) has significantly contributed to reducing the mortality of patients with ST-segment elevation myocardial infarction (STEMI) even in cardiogenic shock and is now the standard of care in most of Japanese institutions. The Task Force on Primary PCI of the Japanese Association of Cardiovascular Interventional and Therapeutics (CVIT) society proposed an expert consensus document for the management of acute myocardial infarction (AMI) focusing on procedural aspects of primary PCI in 2018. Updated guidelines for the management of AMI were published by the European Society of Cardiology (ESC) in 2017 and 2020. Major changes in the guidelines for STEMI patients included: (1) radial access and drug-eluting stents (DES) over bare-metal stents (BMS) were recommended as a Class I indication, (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. In 2020, updated guidelines for Non-ST-Elevation Myocardial Infarction (NSTEMI) patients, the followings were changed: (1) an early invasive strategy within 24 h is recommended in patients with NSTEMI as a Class I indication, (2) complete revascularization in NSTEMI patients without cardiogenic shock is considered as Class IIa recommendation, and (3) in patients with atrial fibrillation following a short period of triple antithrombotic therapy, dual antithrombotic therapy (e.g., DOAC and single oral antiplatelet agent preferably clopidogrel) is recommended, with discontinuation of the antiplatelet agent after 6 to 12 months. Furthermore, an aspirin-free strategy after PCI has been investigated in several trials those have started to show the safety and efficacy. The Task Force on Primary PCI of the CVIT group has now proposed the updated expert consensus document for the management of AMI focusing on procedural aspects of primary PCI in 2022 version.