Real clinical experiences of dual versus triple antithrombotic therapy after percutaneous coronary intervention.

OBJECTIVES: We aimed to assess the impact of omitting aspirin on clinical outcomes in a real-world collective of patients receiving oral anticoagulation (OAC) therapy who were treated with a current-generation drug-eluting stent (DES) or an everolimus-eluting bioresorbable vascular scaffold (BVS). BACKGROUND: Limited data are available regarding the clinical benefit of triple antithrombotic therapy (TAT) with aspirin compared with dual antithrombotic therapy (DAT) without aspirin in patients undergoing percutaneous coronary intervention (PCI) and requiring OAC. METHODS: In total, 237 patients were analyzed. The primary outcome was a composite of major adverse cardiac and cerebrovascular events (MACCE) within 1 year after PCI. Secondary outcomes were the individual components of the primary endpoint, cardiovascular death, and any bleeding according to Bleeding Academic Research Consortium (BARC) or Thrombolysis in Myocardial Infarction (TIMI) criteria. RESULTS: Eighty-nine patients (37.6%) received DAT, and 148 (62.4%) received TAT. The rate of MACCE was significantly higher in DAT patients than in TAT patients (16 (18%) vs. 11 (7.4%); hazard ratio [HR] 2.73, 95% confidence interval [CI] 1.24-6.03; P = 0.01). The results of the multivariable Cox proportional hazards model including corrections for imbalances in baseline characteristics confirmed a significant independent association between DAT and MACCE (HRadj 3.14, 95% CI 1.31-7.54; P = 0.01). Major bleeding did not differ significantly between treatment groups. CONCLUSION: DAT was associated with a significantly higher rate of MACCE than TAT after DES or BVS implantation. Further studies are required to evaluate the safety and efficacy of dual versus TAT after PCI in clinical practice.

Evaluation of the efficacy and safety of dual antiplatelet therapy with or without warfarin in patients with a clinical indication for DAPT and chronic anticoagulation: A meta-analysis of observational studies.

OBJECTIVE: To compare the efficacy and safety of dual antiplatelet therapy (DAPT) and triple therapy (TT, dual antiplatelet plus warfarin) in patients with myocardial infarction (MI) or PCI with stenting (PCI-S) who also require chronic oral anticoagulation. BACKGROUND: Recommendations for the optimal antiplatelet/anticoagulant treatment regimen for patients undergoing PCI-S or MI who also require oral anticoagulation are largely based on evidence from observational studies and expert opinions. METHODS: A systematic search was performed for studies comparing TT vs. DAPT in patients post PCI-S or MI and requiring chronic anticoagulation. Primary outcome was all-cause mortality. Secondary outcomes were ischemic stroke, major bleeding, MI, and stent thrombosis. Pooled relative risks (RR) were calculated using random effects model. RESULTS: A total of 17 studies were included, with 14,921 patients [TT: 5,819(39%) and DAPT: 9,102(61%)] and a mean follow-up of 1.6 years. The majority of patients required oral anticoagulation for atrial fibrillation. Compared to DAPT, patients treated with TT had no significant difference in all-cause mortality [RR: 0.81, 95% confidence interval (CI): 0.61-1.08, P = 0.15], MI [RR 0.74, 95% CI: 0.51-1.06, P = 0.10], and stent thrombosis [RR 0.67, 95% CI: 0.35-1.30, P = 0.24]. Patients treated with TT had significantly increased risk of major bleeding [RR 1.20, 95% CI: 1.03-1.39, P = 0.02], whereas the risk for ischemic stroke was significantly lower [RR 0.59, 95% CI: 0.38-0.92, P = 0.02]. CONCLUSIONS: All-cause mortality appears similar in patients treated with TT or DAPT although TT was associated with higher rates of major bleeding and a lower risk for ischemic stroke. © 2015 Wiley Periodicals, Inc.

Rationale and design of The Intracoronary Stenting and Antithrombotic Regimen-Testing of a six-week versus a six-month clopidogrel treatment Regimen In Patients with concomitant aspirin and oraL anticoagulant therapy following drug-Eluting stenting (ISAR-TRIPLE) study.

BACKGROUND: An increasing number of patients undergoing coronary stenting need lifelong anticoagulation and therefore require a triple therapy typically consisting of aspirin, clopidogrel, and a vitamin K antagonist. Triple therapy confers an elevated bleeding risk as compared with dual therapy; however, omission of either antiplatelet or anticoagulation therapy might increase the risk of stent thrombosis or thrombembolic events. Although guidelines recommend a duration of dual antiplatelet therapy of 6 to 12months after drug-eluting stent (DES) implantation, the optimal duration of dual antiplatelet therapy in patients receiving oral anticoagulation is not known. HYPOTHESIS: We postulate that 6-week clopidogrel therapy after DES implantation as compared with 6-month therapy is associated with improved clinical outcomes in patients undergoing DES implantation receiving concomitant aspirin and vitamin K antagonists. STUDY DESIGN: The ISAR-TRIPLE is a randomized, open-label trial that examines the restriction of clopidogrel therapy from 6 months to 6 weeks after DES implantation in the setting of concomitant aspirin and oral anticoagulant. Patients are randomized in a 1:1 fashion to either 6-week or 6-month clopidogrel therapy. The primary end point is a composite of death, myocardial infarction, definite stent thrombosis, stroke, or major bleeding. The secondary end point comprises ischemic and bleeding complications. According to sample size calculations, a total of 600 patients are required to be enrolled. Clinical follow-up is scheduled at 6 weeks and at 6 and 9 months after randomization. SUMMARY: There is clinical equipoise regarding the optimal duration of triple therapy after DES implantation in patients who need vitamin K antagonist therapy. The ISAR-TRIPLE trial aims to test the hypothesis that a 6-week triple therapy compared with a 6-month triple therapy improves net clinical outcomes.

Association of ST-elevation and non-ST-elevation presentation on ECG with transmurality and size of myocardial infarction as assessed by contrast-enhanced magnetic resonance imaging.

BACKGROUND: It is the general perception, that ST-elevation myocardial infarction is associated with transmural ischemia while Non-ST elevation myocardial infarction is found in non-transmural subendocardial ischemia. This association, however, derives primarily from post mortem studies. METHODS: A total of 220 patients with acute myocardial infarction (MI) who had PCI on admission and contrast-enhanced cardiac magnetic resonance imaging (CMR) within one week were included into the study. Size and transmural extent of MI was quantified by CMR and correlated with the ECG on admission. RESULTS: Based on the ECG findings, 57% were classified as STEMI and 43% as NSTEMI. CMR infarct size was significantly larger in STEMI than NSTEMI (23.2 vs. 14.2 LV%, p<0.001). As assessed by CMR, STEMI patients were transmural in 63% as compared to 27% of patients with NSTEMI (p<0.001). In a multivariable logistic regression model, total infarct size was significantly associated with presence of STEMI (OR: 1.045, 95% CI [1.014-1.077], p=0.004) whereas the number of transmural segments did not significantly add further information for a STEMI/NSTEMI classification (p=0.054, change of c-index from 0.69 to 0.70). CONCLUSIONS: The electrocardiographic STEMI/NSTEMI classification does rather characterize the total size of MI than the transmural extent as assessed by CMR.

Meta-Analysis of Short vs. Prolonged Dual Antiplatelet Therapy after Drug-Eluting Stent Implantation and Role of Continuation with either Aspirin or a P2Y12 Inhibitor Thereafter.

AIM: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an ongoing debate and novel data has emerged. The aim of this meta-analysis was to assess outcomes of short vs. control DAPT duration. In addition, the role of single antiplatelet therapy (SAPT) after DAPT with either aspirin or P2Y12 inhibitor monotherapy was analyzed. METHODS: The authors searched MEDLINE and Cochrane databases and proceedings of international meetings for randomized controlled trials (RCT) comparing ≤ 3 months with ≥ 6 months DAPT after DES implantation. The primary and co-primary outcomes of interest were definite or probable stent thrombosis (ST) and bleeding. In addition, we performed an analysis on studies who continued with either aspirin or P2Y12 monotherapy after DAPT. RESULTS: 9 RCTs comprising 41,864 patients were included and we analyzed a short DAPT duration of median 1.5 months vs. 12.1 months in the control group. The risk for ST was similar with short vs. control DAPT duration (0.5 vs. 0.5%; hazard ratio 1.17[95% CI 0.89-1.54]; p=0.26). Bleeding was significantly reduced with short vs. control DAPT duration (1.9 vs. 3.0%; 0.65[0.54-0.77]; p＜0.0001).ST was not different between short vs. control DAPT duration in the analysis of the 4 RCTs who continued with aspirin after DAPT and the 5 P2Y12 RCTs, respectively, and no heterogeneity was detected (p=0.861). Bleeding was also reduced with short vs. control DAPT in both the aspirin (1.2 vs. 1.7%; 0.71[0.51-0.99]; p=0.04) and P2Y12 inhibitor studies (2.1 vs. 3.4%; 0.62[0.47-0.80]; p=0.0003) and no heterogeneity was detected (p=0.515). CONCLUSIONS: Our meta-analysis shows that short DAPT ≤ 3 months followed by SAPT reduces bleeding and is not associated with an increase in ST. The results were consistent within the aspirin and P2Y12 SAPT studies.

Antiplatelet therapy in patients with atrial fibrillation: a systematic review and meta-analysis of randomized trials.

AIMS: The aim of this study was to systematically assess the effects of antiplatelets on clinical outcomes in patients with atrial fibrillation (AF), treated and not-treated with oral anticoagulation. METHODS AND RESULTS: We searched MEDLINE, Embase, and CENTRAL from inception until September 2020. From 5446 citations, we selected randomized trials allocating patients with AF to antiplatelet therapy vs. control. We applied random-effects models for meta-analysis and assessed potential effect modification with background anticoagulation use. Eighteen trials including 21 518 participants met our prespecified eligibility criteria. In 10 studies without background anticoagulation, antiplatelets reduced all-cause stroke [486/6165 (events/patients) vs. 621/6061; risk ratio (RR) 0.77, 95% confidence interval (CI) 0.69-0.86, I2 = 0%]. In eight studies with background anticoagulation, there was a signal for an increase in all-cause stroke with antiplatelets (97/4608 vs. 72/4684; RR 1.33, 95% CI 0.98-1.79, I2 = 0%, P-value for interaction <0.001). A similar pattern emerged for ischaemic stroke. Irrespective of background anticoagulation use, antiplatelets increased major bleeding (509/10 402 vs. 328/10 496; RR 1.54, 95% CI 1.35-1.77, I2 = 0%) and intracranial haemorrhage (107/10 221 vs. 65/10 232; RR 1.64, 95% CI 1.20-2.24, I2 = 0%), and reduced myocardial infarction (201/9679 vs. 260/9751; RR 0.79, 95% CI 0.65-0.94, I2 = 0%, all P-values for interaction ≥0.36). Antiplatelets did not affect mortality (1221/10 299 vs. 1211/10 287; RR 1.02, 95% CI 0.89-1.17, I2 = 29%, P-value for interaction = 0.23). CONCLUSIONS: In patients with AF not receiving oral anticoagulation, antiplatelet therapy modestly reduced stroke. There was a corresponding signal for harm when used on top of anticoagulation. Irrespective of background anticoagulation use, antiplatelet therapy significantly increased bleeding, moderately reduced myocardial infarction, and did not affect mortality.

Lack of impact of calcium-channel blockers on the pharmacodynamic effect and the clinical efficacy of clopidogrel after drug-eluting stenting.

BACKGROUND: Clopidogrel is a prodrug that is metabolized to its active metabolite by the hepatic cytochrome P450 system. Calcium-channel blockers (CCBs) are metabolized by the same pathway and may therefore attenuate the antiplatelet effect of clopidogrel. The aim of this study was to assess the impact of CCB therapy on the pharmacodynamic effect and the clinical efficacy of clopidogrel after drug-eluting stent placement. METHODS: A total of 1,608 consecutive patients were previously enrolled in a study that aimed to assess the relation between platelet reactivity and outcomes after coronary stenting. Here, this cohort was analyzed according to concomitant CCB therapy at admission. The primary pharmacodynamic end point was adenosine diphosphate-induced platelet aggregation (in AU · min) with multiple electrode platelet aggregometry after loading with 600 mg clopidogrel. The primary clinical end point was combination of death or definite stent thrombosis (ST) at 30 days. Secondary end points included definite ST alone, myocardial infarction, stroke, and death. RESULTS: Two hundred thirty-two patients (14.4%) were on CCBs on admission. Compared with patients with CCB medication, patients without CCB medication showed no significant difference in median [interquartile range] platelet aggregation values (232 [142-365] vs 223 [141-368] AU · min, P = .53). There was also no significant difference regarding the clinical end point of death or ST (2 [0.9%] vs 16 [1.2%], odds ratio 0.74, 95% CI 0.17-3.2, P = .69) between both groups. CONCLUSION: In our population, concomitant CCB therapy did not alter clopidogrel-mediated platelet aggregation and did not have a measurable impact on ST and mortality after coronary stenting.

Oral anticoagulation with coumarin derivatives and antiplatelet effects of clopidogrel.

AIMS: A relevant proportion of patients receiving aspirin and clopidogrel after percutaneous coronary intervention (PCI) also require oral anticoagulation with a coumarin derivative such as phenprocoumon. Both clopidogrel and phenprocoumon are metabolized by the hepatic cytochrome P450 system and a drug-drug interaction may exist at this level. The aim of this study was to investigate the impact of phenprocoumon on the antiplatelet effects of clopidogrel in patients with coronary artery disease. METHODS AND RESULTS: Patients (n = 1223) eligible for this study were under dual maintenance antiplatelet treatment with aspirin and clopidogrel. Adenosine diphosphate-induced platelet aggregation (in AU*min) was measured with multiple electrode platelet aggregometry on a Multiplate analyzer (Dynabyte, Munich, Germany). From the entire study population, 124 (10.1%) patients were under concomitant phenprocoumon treatment at the time point of platelet function testing. Platelet aggregation (median [interquartile range]) was significantly higher in patients with (n = 124) concomitant phenprocoumon treatment compared with patients without (n = 1099) phenprocoumon treatment (308 [190-493] AU*min vs. 224 [145-390] AU*min; P = 0.0001, adjusted P = 0.002). CONCLUSION: Phenprocoumon significantly attenuates the antiplatelet effects of clopidogrel. The impact of this interaction on the risk of thrombotic and bleeding events after PCI requires further investigations.

Comparison of Vascular Closure Devices vs Manual Compression After Femoral Artery Puncture in Patients on Oral Anticoagulation - Post Hoc Analysis of the ISAR-CLOSURE Trial.

OBJECTIVES: To compare vascular closure devices (VCD) with manual compression (MC) in patients on chronic oral anticoagulation (OAC) who undergo diagnostic coronary angiography in terms of vascular access-site complications. METHODS: This is a subanalysis of 604 patients that had undergone transfemoral diagnostic coronary angiography and were randomly assigned to arteriotomy closure with either VCDs (intravascular FemoSeal VCD or extravascular EXOSEAL VCD) or MC within the large scale, randomized ISAR-CLOSURE trial. Primary endpoint was the composite of access-site-related vascular complications at 30 days. Secondary endpoints were time to hemostasis and repeat MC. RESULTS: Vascular access-site complications were similar in patients assigned to VCDs compared to MC (8.2% vs 10.6%; P=.33). There was no interaction of treatment effect and OAC (P interaction = 0.59). Rates of pseudoaneurysms were lower with VCDs (0.8% vs 3.2%; P=.02). Time to hemostasis was significantly shortened with VCDs compared to MC (1 [IQR 0.5-2.0] min vs 12 [IQR 10-15] min; P<.001). There was no difference regarding repeat MC in both groups (VCD 1.5% vs MC 0.5%; P=.23). Time to hemostasis (0.5 [0.2-1.0] min, vs 2.0 [1.75-2.0] min; P<.001) and closure device failure (3.7% vs 17.2%; P<.001) were lower with the intravascular VCD, compared with the extravascular VCD. CONCLUSIONS: In patients on chronic OAC undergoing transfemoral diagnostic coronary angiography, the use of VCDs was comparable to MC regarding the primary combined endpoint of vascular access-site related complications. VCDs reduced the occurrence of pseudoaneurysms and time to hemostasis.

Apixaban versus PhenpRocoumon: Oral AntiCoagulation plus antiplatelet tHerapy in patients with Acute Coronary Syndrome and Atrial Fibrillation (APPROACH-ACS-AF): Rationale and design of the prospective randomized parallel-group, open-label, blinded-endpoint, superiority, multicenter-trial of a triple therapy versus a dual therapy in patients with Atrial Fibrillation and Acute Coronary Syndrome undergoing coronary stenting.

BACKGROUND: A regimen of dual (DAT) vs. triple (TAT) antithrombotic therapy reduces bleeding in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI). However, recent evidence suggests that DAT may be associated with an increased ischemic risk. This raises the question whether DAT rather than TAT should be recommended to AF patients that undergo PCI for acute coronary syndrome (ACS), carrying a particularly high risk of both bleeding and ischemic events, studied only as subgroups of previous trials. METHODS AND DESIGN: The APPROACH-ACS-AF-(DZHK-7) trial is a multicenter prospective, randomized, open-label, blinded endpoint (PROBE) trial which will include patients presenting with an ACS managed by PCI and requiring oral anticoagulation (OAC) due to AF. The trial will test, whether a DAT-regimen comprising clopidogrel plus the non-Vitamin-K-antagonist oral anticoagulant (NOAC) apixaban is superior to a TAT-regimen of vitamin-K-antagonist (VKA) plus dual anti-platelet therapy (APT) with respect to bleeding. A total of 400 patients will be randomized 1:1 to a control-arm with guideline-recommended TAT with VKA plus clopidogrel and acetylsalicylic-acid and a study arm receiving DAT comprising apixaban plus clopidogrel. Patients will be followed-up for 6 months. The primary endpoint of the study is the cumulative incidence of BARC type ≥2 bleeding, secondary endpoints include a composite clinical ischemic outcome and net clinical outcome. CONCLUSIONS: APPROACH-ACS-AF is the first trial dedicated to ACS patients, testing whether in terms of bleeding a DAT with NOAC is superior to a TAT regimen with VKA in high-risk ACS patients with AF.

Optimal Antithrombotic Regimens for Patients With Atrial Fibrillation Undergoing Percutaneous Coronary Intervention: An Updated Network Meta-analysis.

Importance: Antithrombotic treatment in patients with atrial fibrillation (AF) and percutaneous coronary intervention (PCI) presents a balancing act with regard to bleeding and ischemic risks. Objectives: To evaluate the safety and efficacy of 4 antithrombotic regimens by conducting an up-to-date network meta-analysis and to identify the optimal treatment for patients with AF undergoing PCI. Data Sources: Online computerized database (MEDLINE). Study Selection: Five randomized studies were included (N = 11 542; WOEST, PIONEER AF-PCI, RE-DUAL PCI, AUGUSTUS, ENTRUST-AF PCI). Data Extraction and Synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used in this network meta-analysis, in which bayesian random-effects models were applied. The data were analyzed from September 9 to 29, 2019. Main Outcomes and Measures: The primary safety outcome was thrombolysis in myocardial infarction (TIMI) major bleeding and the primary efficacy outcome was trial-defined major adverse cardiovascular events (MACE). Results: The total number of participants included in the study was 11 532. The mean age of the participants ranged from 70 to 72 years, 69% to 83% were male, 20% to 26% were female, and the participants were predominantly white (>90%). Compared with vitamin K antagonists (VKA) plus dual antiplatelet therapy (DAPT) (reference), the odds ratios (ORs) (95% credible intervals) for TIMI major bleeding were 0.57 (0.31-1.00) for VKA plus P2Y12 inhibitor, 0.69 (0.40-1.16) for non-VKA oral anticoagulant (NOAC) plus DAPT, and 0.52 (0.35-0.79) for NOAC plus P2Y12 inhibitor. For MACE, using VKA plus DAPT as reference, the ORs (95% credible intervals) were 0.97 (0.64-1.42) for VKA plus P2Y12 inhibitor, 0.95 (0.64-1.39) for NOAC plus DAPT, and 1.03 (0.77-1.38) for NOAC plus P2Y12 inhibitor. Conclusions and Relevance: The findings of this study suggest that an antithrombotic regimen of VKA plus DAPT should generally be avoided, because regimens in which aspirin is discontinued may lead to lower bleeding risk and no difference in antithrombotic effectiveness. The use of a NOAC plus a P2Y12 inhibitor without aspirin may be the most favorable treatment option and the preferred antithrombotic regimen for most patients with AF undergoing PCI.

Enhanced platelet inhibition by clopidogrel and risk of bleeding in patients requiring oral anticoagulation after drug-eluting stent implantation.

AIMS: Clopidogrel is the P2Y12 inhibitor of choice in patients who undergo PCI and have an indication for oral anticoagulation (OAC). Prediction of the bleeding risk is of major interest in this population. The aim of this analysis was to investigate whether an enhanced platelet inhibition by clopidogrel measured by platelet function testing (PFT) with the Multiplate Analyzer is associated with an increased bleeding risk in patients on triple antithrombotic therapy. METHODS AND RESULTS: This investigation was performed in a cohort of 524 patients from the randomised ISAR-TRIPLE trial; 458 (87.4%) had PFT results available in the first 24 hours after PCI. Patients belonging to the lowest quintile according to PFT were considered as enhanced responders to clopidogrel. The primary endpoint was major bleeding according to TIMI criteria at nine months. The median of ADP-induced platelet aggregation in the whole population was 163 AU*min (107-241). Patients in the lowest quintile had values below 93 AU*min. These enhanced responders (92 patients) had a significantly higher risk of TIMI major bleeding (hazard ratio [HR] 3.13, 95% confidence interval [CI]: 1.38-7.09, p=0.01) and overall mortality (HR 3.42, 95% CI: 1.55-7.52, p=0.004) compared with the remaining patients (366 patients). No significant difference was observed for the secondary combined ischaemic endpoint (HR 1.27, 95% CI: 0.47-3.47, p=0.64). CONCLUSIONS: Enhanced platelet inhibition delivered by clopidogrel is associated with an increased risk for major bleeding and death in patients on OAC who undergo PCI. These results support the use of PFT to identify patients with an increased risk for bleeding.

Safety and Efficacy of Antithrombotic Strategies in Patients With Atrial Fibrillation Undergoing Percutaneous Coronary Intervention: A Network Meta-analysis of Randomized Controlled Trials.

Importance: The antithrombotic treatment of patients with atrial fibrillation (AF) and coronary artery disease, in particular with acute coronary syndrome (ACS) and/or percutaneous coronary intervention (PCI), poses a significant treatment dilemma in clinical practice. Objective: To study the safety and efficacy of different antithrombotic regimens using a network meta-analysis of randomized controlled trials in this population. Data Sources: PubMed, EMBASE, EBSCO, and Cochrane databases were searched to identify randomized controlled trials comparing antithrombotic regimens. Study Selection: Four randomized studies were included (n = 10 026; WOEST, PIONEER AF-PCI, RE-DUAL PCI, and AUGUSTUS). Data Extraction and Synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in this systematic review and network meta-analysis between 4 regimens using a Bayesian random-effects model. A pre hoc statistical analysis plan was written, and the review protocol was registered at PROSPERO. Data were analyzed between November 2018 and February 2019. Main Outcomes and Measures: The primary safety outcome was Thrombolysis in Myocardial Infarction (TIMI) major bleeding; secondary safety outcomes were combined TIMI major and minor bleeding, trial-defined primary bleeding events, intracranial hemorrhage, and hospitalization. The primary efficacy outcome was trial-defined major adverse cardiovascular events (MACE); secondary efficacy outcomes were individual components of MACE. Results: The overall prevalence of ACS varied from 28% to 61%. The mean age ranged from 70 to 72 years; 20% to 29% of the trial population were women; and most patients were at high risk for thromboembolic and bleeding events. Compared with a regimen of vitamin K antagonist (VKA) plus dual antiplatelet therapy (DAPT; P2Y12 inhibitor plus aspirin), the odds ratios (ORs) for TIMI major bleeding were 0.58 (95% CI, 0.31-1.08) for VKA plus P2Y12 inhibitor, 0.49 (95% CI, 0.30-0.82) for non-VKA oral anticoagulant (NOAC) plus P2Y12 inhibitor, and 0.70 (95% CI, 0.38-1.23) for NOAC plus DAPT. Compared with VKA plus DAPT, the ORs for MACE were 0.96 (95% CI, 0.60-1.46) for VKA plus P2Y12 inhibitor, 1.02 (95% CI, 0.71-1.47) for NOAC plus P2Y12 inhibitor, and 0.94 (95% CI, 0.60-1.45) for NOAC plus DAPT. Conclusions and Relevance: A regimen of NOACs plus P2Y12 inhibitor was associated with less bleeding compared with VKAs plus DAPT. Strategies omitting aspirin caused less bleeding, including intracranial bleeding, without significant difference in MACE, compared with strategies including aspirin. Our results support the use of NOAC plus P2Y12 inhibitor as the preferred regimen post-percutaneous coronary intervention for these high-risk patients with AF. A regimen of VKA plus DAPT should generally be avoided.

Automated PrPres amplification using indirect sonication.

Prions, which mainly consist of the scrapie isoform of the prion protein (PrP(Sc)), induce the misfolding of the physiological prion protein (PrP(C)). The Protein Misfolding Cyclic Amplification (PMCA), a process consisting of sonication and incubation, is one of the few methods thought to model autocatalytic prion replication and generation of proteinase K (PK)-resistant PrP (PrPres) in vitro. Here we show for the first time that the amplification may be achieved through direct as well as indirect sonication (water bath sonication using sealed sample containers), allowing the PMCA method to be automated. The automated method may serve as a valuable tool in high throughput screening for the diagnosis or compound identification for treatment of prion disease. The in vitro amplification process is weakly facilitated by divalent cations such as Mn, Zn and Ni, but not Cu, however, the presence of metal ions decreases the stability of PrPres against proteinase K digestion.

ICD Shock, Not Ventricular Fibrillation, Causes Elevation of High Sensitive Troponin T after Defibrillation Threshold Testing--The Prospective, Randomized, Multicentre TropShock-Trial.

BACKGROUND: The placement of an implantable cardioverter defibrillator (ICD) has become routine practice to protect high risk patients from sudden cardiac death. However, implantation-related myocardial micro-damage and its relation to different implantation strategies are poorly characterized. METHODS: A total of 194 ICD recipients (64±12 years, 83% male, 95% primary prevention of sudden cardiac death, 35% cardiac resynchronization therapy) were randomly assigned to one of three implantation strategies: (1) ICD implantation without any defibrillation threshold (DFT) testing, (2) estimation of the DFT without arrhythmia induction (modified "upper limit of vulnerability (ULV) testing") or (3) traditional safety margin testing including ventricular arrhythmia induction. High-sensitive Troponin T (hsTnT) levels were determined prior to the implantation and 6 hours after. RESULTS: All three groups showed a postoperative increase of hsTnT. The mean delta was 0.031±0.032 ng/ml for patients without DFT testing, 0.080±0.067 ng/ml for the modified ULV-testing and 0.064±0.056 ng/ml for patients with traditional safety margin testing. Delta hsTnT was significantly larger in both of the groups with intraoperative ICD testing compared to the non-testing strategy (p≤0.001 each). There was no statistical difference in delta hsTnT between the two groups with intraoperative ICD testing (p = 0.179). CONCLUSION: High-sensitive Troponin T release during ICD implantation is significantly higher in patients with intraoperative ICD testing using shock applications compared to those without testing. Shock applications, with or without arrhythmia induction, did not result in a significantly different delta hsTnT. Hence, the ICD shock itself and not ventricular fibrillation seems to cause myocardial micro-damage. TRIAL REGISTRATION: ClinicalTrials.gov NCT01230086.

Impact of Dabigatran versus Phenprocoumon on ADP Induced Platelet Aggregation in Patients with Atrial Fibrillation with or without Concomitant Clopidogrel Therapy (the Dabi-ADP-1 and Dabi-ADP-2 Trials).

BACKGROUND: A relevant number of patients receive triple therapy with clopidogrel, aspirin, and oral anticoagulation. Clopidogrel's efficacy on ADP induced platelet function may be influenced by concomitant antithrombotic therapies. Data regarding the effect of dabigatran on platelet function is limited to in vitro studies and healthy individuals. METHODS: The "Dabi-ADP-1" and "Dabi-ADP-2" trials randomized patients with atrial fibrillation to either dabigatran or phenprocoumon for a 2-week period. In Dabi-ADP-1 (n = 70) patients with clopidogrel therapy were excluded and in Dabi-ADP-2 (n = 46) patients had to be treated concomitantly with clopidogrel. The primary endpoint was ADP-induced platelet aggregation between dabigatran and phenprocoumon at 14 days. Secondary endpoints were ADPtest HS-, TRAP-, and COL-induced platelet aggregation. RESULTS: There was no significant difference regarding the primary endpoint between both groups in either trial (Dabi-ADP-1: Dabigatran: 846 [650-983] AU × min versus phenprocoumon: 839 [666-1039] AU × min, P = 0.90 and Dabi-ADP-2: 326 [268-462] versus 350 [214-535], P = 0.70) or regarding the secondary endpoints, ADPtest HS-, TRAP-, and COL-induced platelet aggregation. CONCLUSION: Dabigatran as compared to phenprocoumon has no impact on ADP-induced platelet aggregation in atrial fibrillation patients neither with nor without concomitant clopidogrel therapy.

Duration of Triple Therapy in Patients Requiring Oral Anticoagulation After Drug-Eluting Stent Implantation: The ISAR-TRIPLE Trial.

BACKGROUND: Patients receiving oral anticoagulation (OAC) who undergo drug-eluting stent (DES) implantation require additional dual antiplatelet therapy with aspirin and clopidogrel. Such triple therapy confers an elevated bleeding risk, and its optimal duration is not known. OBJECTIVES: The goal of this study was to evaluate whether shortening the duration of clopidogrel therapy from 6 months to 6 weeks after DES implantation was associated with a superior net clinical outcome in patients receiving concomitant aspirin and OAC. METHODS: In this randomized, open-label trial, we enrolled patients receiving OAC who underwent DES implantation at 3 European centers between September 2008 and December 2013. A total of 614 patients receiving concomitant aspirin and OAC were randomized to either 6-week clopidogrel therapy (n=307) or 6-month clopidogrel therapy (n=307). The primary endpoint was a composite of death, myocardial infarction (MI), definite stent thrombosis, stroke, or Thrombolysis In Myocardial Infarction (TIMI) major bleeding at 9 months. RESULTS: The primary endpoint occurred in 30 patients (9.8%) in the 6-week group compared with 27 patients (8.8%) in the 6-month group (hazard ratio [HR]: 1.14; 95% CI: 0.68 to 1.91; p=0.63). There were no significant differences for the secondary combined ischemic endpoint of cardiac death, MI, definite stent thrombosis, and ischemic stroke (12 [4.0%] vs. 13 [4.3%]; HR: 0.93; 95% CI: 0.43 to 2.05; p=0.87) or the secondary bleeding endpoint of TIMI major bleeding (16 [5.3%] vs. 12 [4.0%]; HR: 1.35; 95% CI: 0.64 to 2.84; p=0.44). CONCLUSIONS: Six weeks of triple therapy was not superior to 6 months with respect to net clinical outcomes. These results suggest that physicians should weigh the trade-off between ischemic and bleeding risk when choosing the shorter or longer duration of triple therapy. (Triple Therapy in Patients on Oral Anticoagulation After Drug Eluting Stent Implantation [ISAR-TRIPLE]; NCT00776633).