Objective The effects of ticagrelor in the subpopulation of patients with ST-elevation myocardial infarction (STEMI) were consistent with those observed in the overall Platelet Inhibition and Patient Outcomes (PLATO) study. However, this subgroup included patients initially or ultimately treated conservatively. The aim of this study is to compare treatment using ticagrelor with treatment using clopidogrel in patients with STEMI undergoing primary percutaneous coronary intervention (PCI). Methods This post-hoc subgroup analysis compared ticagrelor with clopidogrel in 4949 PLATO patients with STEMI that were treated with primary PCI within 12 h of admission. The primary endpoint was cardiovascular death, myocardial infarction or stroke. The safety endpoint consisted of any major bleeding. Secondary endpoints included stent thrombosis. The analysis was not adequately powered to establish significance of any treatment effects. Results During a median of 286 days, the primary endpoint occurred in 7.9% of ticagrelor-treated patients versus 8.6% of clopidogrel-treated patients (HR 0.91, 95% CI 0.75 to 1.12, p=0.38). Major bleeding occurred in 6.7% in ticagrelor-treated patients versus 6.8% of clopidogrel-treated patients (HR 0.97, 95% CI 0.77 to 1.22, p=0.79). No interactions were observed for the treatment effect of ticagrelor versus clopidogrel on the primary efficacy (p=0.40) and primary safety endpoints (p=0.15) as compared with the full PLATO population. Treatment with ticagrelor versus clopidogrel reduced the occurrence of definite stent thrombosis (HR 0.58, 95% CI 0.37 to 0.89, p=0.013). Conclusions In the subset of patients with STEMI treated with primary PCI, ticagrelor compared with clopidogrel was safe, and efficacy outcomes were consistent with the overall PLATO trial. Trial registration number NCT00391872; Results.
Blood Pressure Control and Risk of Stroke or Systemic Embolism in Patients With Atrial Fibrillation: Results From the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) Trial
Background Patients with atrial fibrillation ( AF ) and hypertension are at high risk for stroke. Previous studies have shown elevated risk of stroke in patients with AF who have a history of hypertension (regardless of blood pressure [ BP ] control) and in patients with elevated BP . We assessed the association of hypertension and BP control on clinical outcomes. Methods and Results In ARISTOTLE (n=18 201), BP was evaluated as history of hypertension requiring treatment and elevated BP (systolic ≥140 and/or diastolic ≥90 mm Hg) at study entry and any point during the trial. Hazard ratios ( HR s) were derived from Cox proportional hazards models including BP as a time‐dependent covariate. A total of 15 916 (87.5%) patients had a history of hypertension requiring treatment. In patients with elevated BP measurement at any point during the trial, the rate of stroke or systemic embolism was significantly higher ( HR , 1.53; 95% confidence interval [ CI ], 1.25–1.86), as was hemorrhagic stroke ( HR 1.85; 95% CI , 1.26–2.72) and ischemic stroke ( HR , 1.50; 95% CI , 1.18–1.90). Rates of major bleeding were lower in patients with a history of hypertension ( HR , 0.80; 95% CI , 0.66–0.98) and nonsignificantly lower in patients with elevated BP at study entry ( HR , 0.89; 95% CI , 0.77–1.03). The benefit of apixaban versus warfarin on preventing stroke or systemic embolism was consistent among patients with and without a history of hypertension ( P interaction=0.27), BP control at baseline ( P interaction=0.43), and BP control during the trial ( P interaction=0.97). Conclusions High BP measurement at any point during the trial was independently associated with a substantially higher risk of stroke or systemic embolism. These results strongly support efforts to treat elevated BP as an important strategy to optimally lower risk of stroke in patients with AF . Clinical Trial Registration URL : https://ClinicalTrials.gov/ . Unique identifier: NCT 00412984.
Comparison of Cardiac Troponins I and T Measured with High-Sensitivity Methods for Evaluation of Prognosis in Atrial Fibrillation: An ARISTOTLE Substudy
Abstract BACKGROUND Although cardiac troponin is associated with outcomes in atrial fibrillation (AF), the complementary prognostic information provided by cardiac troponin I (cTnI) and cTnT is unknown. This study investigated the distribution, determinants, and prognostic value of cTnI and cTnT concentrations in patients with AF. METHODS Samples were collected. At the time of randomization, we analyzed cTnI and cTnT concentrations of 14806 AF patients in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial using high-sensitivity assays. Correlations (Spearman), determinants (multivariable linear regression), and outcomes (adjusted Cox models and c-statistics) were investigated. RESULTS Concentrations of cTnI and cTnT were correlated (r = 0.70) and measurable in most participants [cTnI 98.5% (median 5.4 ng/L, ≥99th percentile in 9.2%) and cTnT 93.5% (median 10.9 ng/L, ≥99th percentile in 34.4%)]. Renal impairment was the most important factor affecting the concentrations of both troponins. cTnI increase was more associated with heart failure, vascular disease, and persistent/permanent AF, and cTnT with age, male sex, and diabetes. Over a median 1.9 years of follow-up, patients with both troponins above the median had significantly higher risk for stroke/systemic embolism [hazard ratio (HR) 1.72 (95% CI 1.31–2.27)], cardiac death [3.14 (2.35–4.20)], and myocardial infarction [2.99 (1.78–5.03)] than those with both troponins below median (all P < 0.005). Intermediate risks were observed when only 1 troponin was above the median. When combined with clinical information, each marker provided similar prognostication and had comparable c-index. CONCLUSIONS cTnI and cTnT concentrations are moderately correlated and measurable in plasma of most AF patients. The risk of stroke and cardiovascular events is highest when both troponins are above median concentrations. Each troponin provides comparable prognostic information when combined with clinical risk factors. ClinicalTrials.gov/NCT00412984