2011 ACCF/AHA Focused Update of the Guidelines for the Management of Patients With Unstable Angina/Non–ST-Elevation Myocardial Infarction (Updating the 2007 Guideline)

Treatment with adenosine diphosphate receptor inhibitors-longitudinal assessment of treatment patterns and events after acute coronary syndrome (TRANSLATE-ACS) study design: expanding the paradigm of longitudinal observational research

BACKGROUND

Platelet inhibition is critical in reducing both short- and long-term atherothrombotic risks after acute myocardial infarction (MI), especially among patients managed with percutaneous coronary intervention (PCI). Currently available antiplatelet medications, including adenosine diphosphate (ADP) receptor inhibitors, have demonstrated variability in efficacy and safety in clinical trials, yet few studies have examined contemporary "real-world" approaches to platelet inhibition and associated outcomes.

METHODS

TRANSLATE-ACS is a prospective observational study that will track up to 17,000 MI patients managed with PCI, from the inhospital to outpatient settings for up to 12 months postdischarge to provide a comprehensive picture of current treatment patterns and outcomes in routine clinical practice. TRANSLATE-ACS exemplifies a collaborative study design that efficiently builds upon a well-established PCI registry platform, and yet, through a systematic telephone interview follow-up process, provides important longitudinal clinical and economic follow-up capacity through 15 months after initial MI hospitalization. Furthermore, TRANSLATE-ACS incorporates a hospital-level, clustered, randomized substudy to investigate the impact of point-of-care platelet inhibition testing on subsequent patient management. Finally, TRANSLATE-ACS provides feedback through quarterly reports to participating sites on their care practices benchmarked to peer performance to support and promote longitudinal quality of cardiovascular care delivery.

CONCLUSION

TRANSLATE-ACS not only addresses important clinical and scientific questions but also includes pioneering design features that will assist in the evolution of clinical registries.

Ticagrelor Compared With Clopidogrel by Geographic Region in the Platelet Inhibition and Patient Outcomes (PLATO) Trial

Background—

In the Platelet Inhibition and Patient Outcomes (PLATO) trial, a prespecified subgroup analysis showed a significant interaction between treatment and region ( P =0.045), with less effect of ticagrelor in North America than in the rest of the world.

Methods and Results—

Reasons for the interaction were explored independently by 2 statistical groups. Systematic errors in trial conduct were investigated. Statistical approaches evaluated the likelihood of play of chance. Cox regression analyses were performed to quantify how much of the regional interaction could be explained by patient characteristics and concomitant treatments, including aspirin maintenance therapy. Landmark Cox regressions at 8 time points evaluated the association of selected factors, including aspirin dose, with outcomes by treatment. Systematic errors in trial conduct were ruled out. Given the large number of subgroup analyses performed and that a result numerically favoring clopidogrel in at least 1 of the 4 prespecified regions could occur with 32% probability, chance alone cannot be ruled out. More patients in the United States (53.6%) than in the rest of the world (1.7%) took a median aspirin dose ≥300 mg/d. Of 37 baseline and postrandomization factors explored, only aspirin dose explained a substantial fraction of the regional interaction. In adjusted analyses, both Cox regression with median maintenance dose and landmark techniques showed that, in patients taking low-dose maintenance aspirin, ticagrelor was associated with better outcomes compared with clopidogrel, with statistical superiority in the rest of the world and similar outcomes in the US cohort.

Conclusions—

The regional interaction could arise from chance alone. Results of 2 independently performed analyses identified an underlying statistical interaction with aspirin maintenance dose as a possible explanation for the regional difference. The lowest risk of cardiovascular death, myocardial infarction, or stroke with ticagrelor compared with clopidogrel is associated with a low maintenance dose of concomitant aspirin.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00391872.

Immediate and Long-Term Therapy of Patients with Acute Coronary Syndromes with Thienopyridines. Current Status According to the Latest European Society of Cardiology (ESC) Guidelines

For patients with acute coronary syndrome (ACS), the first priority is to alert emergency services. In addition to an ECG (ideally taken during the first medical contact at the patient's home), the key of life saving is the immediate antithrombotic therapy with acetylsalicylic acid (ASA) and (unless contraindicated) an injection of unfractionated heparin or bivalirudin as an alternative anticoagulant. Dual anti-platelet therapy (ASA combined with other antiplatelet drugs, like thienopyridines) should be started as soon as possible in the ambulance or at the latest in the hospital. For clopidogrel, a loading dose of 600 mg is the standard. To avoid the risk of an unknown low or missing clopidogrel response, prasugrel is recommended instead, with administration of a loading dose of 60 mg, if no contraindication (s/p stroke or TIA) exists. When PCI is planned, the ambulance must head directly to the nearest hospital with continuous (24/7) PCI service within 90 (to 120) minutes. The maintenance dose for clopidogrel is 75 mg/d; a daily double-dose has not proven to be superior, even in "low responders". For prasugrel, the maintenance dose is usually 10 mg/d. To avoid bleeding complications in patients ≥ 75 y and/or < 60 kg, a prasugrel maintenance dose of 5 mg/d is recommended. The ESC guidelines recommend DAPT for 1 year after ACS in all patients - independent of the type of ACS and independent of whether any or which coronary stent has been implanted. With DAPT, the patient - and not the stent - is treated.