IMPORTANCE Discontinuing aspirin after short-term dual antiplatelet therapy (DAPT) was evaluated as a bleeding reduction strategy. However, the strategy of ticagrelor monotherapy has not been exclusively evaluated in patients with acute coronary syndromes (ACS). OBJECTIVE To determine whether switching to ticagrelor monotherapy after 3 months of DAPT reduces net adverse clinical events compared with ticagrelor-based 12-month DAPT in patients with ACS treated with drug-eluting stents. DESIGN, SETTING, AND PARTICIPANTS A randomized multicenter trial was conducted in 3056 patients with ACS treated with drug-eluting stents between August 2015 and October 2018 at 38 centers in South Korea. Follow-up was completed in October 2019. INTERVENTIONS Patients were randomized to receive ticagrelor monotherapy (90 mg twice daily) after 3-month DAPT (n = 1527) or ticagrelor-based 12-month DAPT (n = 1529). MAIN OUTCOMES AND MEASURES The primary outcome was a 1-year net adverse clinical event, defined as a composite of major bleeding and adverse cardiac and cerebrovascular events (death, myocardial infarction, stent thrombosis, stroke, or target-vessel revascularization). Prespecified secondary outcomes included major bleeding and major adverse cardiac and cerebrovascular events. RESULTS Among 3056 patients who were randomized (mean age, 61 years; 628 women [20%]; 36% ST-elevation myocardial infarction), 2978 patients (97.4%) completed the trial. The primary outcome occurred in 59 patients (3.9%) receiving ticagrelor monotherapy after 3-month DAPT and in 89 patients (5.9%) receiving ticagrelor-based 12-month DAPT (absolute difference, −1.98% [95% CI, −3.50% to −0.45%]; hazard ratio [HR], 0.66 [95% CI, 0.48 to 0.92]; P = .01). Of 10 prespecified secondary outcomes, 8 showed no significant difference. Major bleeding occurred in 1.7% of patients with ticagrelor monotherapy after 3-month DAPT and in 3.0% of patients with ticagrelor-based 12-month DAPT (HR, 0.56 [95% CI, 0.34 to 0.91]; P = .02). The incidence of major adverse cardiac and cerebrovascular events was not significantly different between the ticagrelor monotherapy after 3-month DAPT group (2.3%) vs the ticagrelor-based 12-month DAPT group (3.4%) (HR, 0.69 [95% CI, 0.45 to 1.06]; P = .09). CONCLUSIONS AND RELEVANCE Among patients with acute coronary syndromes treated with drug-eluting stents, ticagrelor monotherapy after 3 months of dual antiplatelet therapy, compared with ticagrelor-based 12-month dual antiplatelet therapy, resulted in a modest but statistically significant reduction in a composite outcome of major bleeding and cardiovascular events at 1 year. The study population and lower than expected event rates should be considered in interpreting the trial.

Mesenchymal stem cell (MSC) implantation has emerged as a potential therapy for myocardial infarction (MI). However, the poor survival of MSCs implanted to treat MI has significantly limited the therapeutic efficacy of this approach. This poor survival is primarily due to reactive oxygen species (ROS) generated in the ischemic myocardium after the restoration of blood flow. ROS primarily causes the death of implanted MSCs by inhibiting the adhesion of the MSCs to extracellular matrices at the lesion site (i.e., anoikis). In this study, we proposed the use of graphene oxide (GO) flakes to protect the implanted MSCs from ROS-mediated death and thereby improve the therapeutic efficacy of the MSCs. GO can adsorb extracellular matrix (ECM) proteins. The survival of MSCs, which had adhered to ECM protein-adsorbed GO flakes and were subsequently exposed to ROS in vitro or implanted into the ischemia-damaged and reperfused myocardium, significantly exceeded that of unmodified MSCs. Furthermore, the MSC engraftment improved by the adhesion of MSCs to GO flakes prior to implantation enhanced the paracrine secretion from the MSCs following MSC implantation, which in turn promoted cardiac tissue repair and cardiac function restoration. This study demonstrates that GO can effectively improve the engraftment and therapeutic efficacy of MSCs used to repair the injury of ROS-abundant ischemia and reperfusion by protecting implanted cells from anoikis.

Objective To investigate the long-term prognostic implications of contrast-induced acute kidney injury (CI-AKI) with transient or persistent renal dysfunction in acute myocardial infarction (AMI) patients undergoing percutaneous coronary intervention (PCI). Design A retrospective observational registry study. Setting Clinical follow-up after PCI. Patients and methods A total of 1041 PCI-treated AMI patients from the Infarction Prognosis Study registry. CI-AKI was defined as an increase in serum creatinine (>25% or >0.5 mg/dl (>44.2 mmol/l)) within 2 days after PCI. Main outcome measures Two-year cumulative event rate of all-cause death or renal failure requiring dialysis. Results CI-AKI was observed in 148 patients (14.2%). Patients with CI-AKI had a higher rate of death or dialysis (25.4% vs 6.3%, p<0.001) at 2 years compared with patients without CI-AKI. CI-AKI was an important independent predictor of death or dialysis (HR 2.76, 95% CI 1.61 to 4.73, p<0.001) Persistent renal dysfunction after CI-AKI was documented in 68 patients (45.9%). Patients with transient renal dysfunction showed a lower 2-year event rate of death or dialysis compared with those with persistent renal dysfunction (17.9% vs 34.1%, p¼0.013); however, they showed a higher event rate compared with those without CI-AKI (17.9% vs 6.3%, p<0.001). Conclusion Transient and persistent renal dysfunction after CI-AKI was associated with increased short and longterm mortality and morbidity in AMI patients treated by PCI. Better preventive strategies are needed to improve clinical outcomes in AMI patients at high risk of developing CI-AKI.Contrast-induced acute kidney injury (CI-AKI) is generally considered a reversible form of acute renal failure that begins soon after iodinated contrast administration during angiographic procedures. This hospital-acquired complication is of great concern because of its adverse effects on patients' clinical outcomes, including prolonged hospitalisation and increased morbidity and mortality.1 2 Important predisposing factors for CI-AKI include female gender, older age, diabetes mellitus, pre-existing renal insufficiency, advanced heart failure and intravascular volume depletion. 3e5 The risk of CI-AKI is significantly higher among patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) than among the general population undergoing elective PCI. 6e10 The most likely contributing factors for CI-AKI in patients with AMI are haemodynamic instability or impaired systemic perfusion caused by left ventricular dysfunction, large volume of contrast medium, or insufficient time to perform renal prophylactic therapies during contrast medium exposure. 7 The purpose of this study was to determine the incidence of CI-AKI in patients with AMI undergoing PCI and to evaluate clinical predictors and long-term prognostic implications of CI-AKI in these patients. METHODS Study populationThe registry of the Infarction Prognosis Study, a prospective single-centre cohort study, is maintai...

Background-Whether triple antiplatelet therapy is superior or similar to dual antiplatelet therapy in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention in the era of drug-eluting stents remains unclear. Methods and Results-A total of 4203 ST-segment elevation myocardial infarction patients who underwent primary percutaneous coronary intervention with drug-eluting stents were analyzed retrospectively in the Korean Acute Myocardial Infarction Registry (KAMIR). They received either dual (aspirin plus clopidogrel; dual group; nϭ2569) or triple (aspirin plus clopidogrel plus cilostazol; triple group; nϭ1634) antiplatelet therapy. The triple group received additional cilostazol at least for 1 month. Various major adverse cardiac events at 8 months were compared between these 2 groups. Compared with the dual group, the triple group had a similar incidence of major bleeding events but a significantly lower incidence of in-hospital mortality. Clinical outcomes at 8 months showed that the triple group had significantly lower incidences of cardiac death (adjusted odds ratio, 0.52; 95% confidence interval, 0.32 to 0.84; Pϭ0.007), total death (adjusted odds ratio, 0.60; 95% confidence interval, 0.41 to 0.89; Pϭ0.010), and total major adverse cardiac events (adjusted odds ratio, 0.74; 95% confidence interval, 0.58 to 0.95; Pϭ0.019) than the dual group. Subgroup analysis showed that older (Ͼ65 years old), female, and diabetic patients got more benefits from triple antiplatelet therapy than their counterparts who received dual antiplatelet therapy. Conclusions-Triple antiplatelet therapy seems to be superior to dual antiplatelet therapy in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with drug-eluting stents. These results may provide the rationale for the use of triple antiplatelet therapy in these patients. (Circulation. 2009;119:3207-3214.)

High-dose atorvastatin pre-treatment before PCI did not show a significant reduction of MACEs compared with low-dose atorvastatin but did show improved immediate coronary flow after primary PCI. High-dose atorvastatin may produce an optimal result for STEMI patients undergoing PCI by improving microvascular myocardial perfusion. (Efficacy of High-Dose AtorvaSTATIN Loading Before Primary Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction [STATIN STEMI]; NCT00808717).

E-ZES+3-month DAPT was noninferior to the standard therapy with respect to the occurrence of the primary endpoint. (REal Safety and Efficacy of a 3-month dual antiplatelet Therapy following E-ZES implantation [RESET]; NCT01145079).

Background-Previous studies suggested that statin pretreatment reduces cardiac events in patients undergoing percutaneous coronary intervention. However, most data were observational, and single randomized trials included limited numbers of patients. Methods and Results-We performed a collaborative meta-analysis using individual patient data from 13 randomized studies in which 3341 patients received either high-dose statin (nϭ1692) or no statin/low-dose statin (nϭ1649) before percutaneous coronary intervention, with all patients receiving statin therapy after intervention. Occurrence of periprocedural myocardial infarction, defined as postintervention creatine kinase-MB increase Ն3 times the upper limit of normal, and 30-day major adverse cardiac events (death, myocardial infarction, target-vessel revascularization) was evaluated. Incidence of periprocedural myocardial infarction was 7.0% in the high-dose statin versus 11.9% in the control group, which corresponds to a 44% risk reduction in the active-treatment arm (odds ratio by fixed-effects model 0.56, 95% confidence interval, 0.44 to 0.71, PϽ0.00001). The rate of major adverse cardiac events at 30 days was significantly lower in the high-dose statin group (7.4% versus 12.6%, a 44% risk reduction; PϽ0.00001), and 1-month major adverse cardiac events, excluding periprocedural events, were also reduced (0.6% versus 1.4%; Pϭ0.05). The benefit of high-dose statins was realized irrespective of clinical presentation (P for interactionϭ0.43) and was maintained across various subgroups but appeared greater in the subgroup with elevated baseline C-reactive protein levels (nϭ734; 68% risk reduction for periprocedural myocardial infarction versus 31% in those 1861 patients with normal CRP; P for quantitative interactionϭ0.025). Conclusions-High-dose statin pretreatment leads to a significant reduction in periprocedural myocardial infarction and 30-day adverse events in patients undergoing percutaneous coronary intervention. This strategy should be considered in all patients with planned percutaneous coronary intervention. (Circulation. 2011;123:1622-1632.)Key Words: statins, HMG-CoA Ⅲ outcomes assessment Ⅲ protective agents Ⅲ meta-analysis Ⅲ stents P ercutaneous coronary intervention (PCI) represents the prevalent revascularization strategy in patients with coronary artery disease. Although this procedure is safe and is associated with low rates of severe complications, periprocedural myocardial infarction, as assessed by cardiac marker elevation, occurs in 5% to 40% of patients, depending on the definition applied, antithrombotic approaches, and clinical/ angiographic risk profile, [1][2][3][4] and it is well known that this complication may negatively impact clinical outcome after intervention. 2,3,5 Thus, various strategies, usually focused on Continuing medical education (CME) credit is available for this article. Go to http://cme.ahajournals.org to take the quiz. Received October 14, 2010; accepted February 14, 2011. Clinical Perspective on p 1632In the last few...

Paclitaxel-eluting stents used with conventional antiplatelet therapy effectively inhibit restenosis and neointimal hyperplasia, with a safety profile similar to that of standard stents.