A review of antithrombotic therapy and the rationale and design of the randomized edoxaban in patients with peripheral artery disease (ePAD) trial adding edoxaban or clopidogrel to aspirin after femoropopliteal endovascular intervention.

Compared with the coronary setting, knowledge about antithrombotic therapies after endovascular treatment (EVT) is inadequate in patients with peripheral artery disease (PAD). Based on a review of trials and guidelines, which is summarized in this article, there is scant evidence that antithrombotic drugs improve outcome after peripheral EVT. To address this knowledge gap, the randomized, open-label, multinational edoxaban in patients with Peripheral Artery Disease (ePAD) study (ClinicalTrials.gov identifier NCT01802775) was designed to explore the safety and efficacy of a combined regimen of antiplatelet therapy with clopidogrel and anticoagulation with edoxaban, a selective and direct factor Xa inhibitor, both combined with aspirin. As of July 2014, 203 patients (144 men; mean age 67 years) from 7 countries have been enrolled. These patients have been allocated to once-daily edoxaban [60 mg for 3 months (or 30 mg in the presence of factors associated with increased exposure)] or clopidogrel (75 mg/d for 3 months). All patients received aspirin (100 mg/d) for the 6-month duration of the study. The primary safety endpoint is major or clinically relevant nonmajor bleeding; the primary efficacy endpoint is restenosis or reocclusion at the treated segment(s) measured at 1, 3, and 6 months using duplex ultrasound scanning. All outcomes will be assessed and adjudicated centrally in a masked fashion. The ePAD study is the first of its kind to investigate a combined regimen of antiplatelet therapy and anticoagulation through factor Xa inhibition with edoxaban.

Antithrombotic therapy in TAVI patients: changing concepts.

The clinical and demographic characteristics of patients undergoing TAVI pose unique challenges for developing and implementing optimal antithrombotic therapy. Ischaemic and bleeding events in the periprocedural period and months after TAVI still remain a relevant concern to be faced with optimised antithrombotic therapy. Moreover, the antiplatelet and anticoagulant pharmacopeia has evolved significantly in recent years with new drugs and multiple possible combinations. Dual antiplatelet therapy (DAPT) is currently recommended after TAVI with oral anticoagulation (OAC) restricted for specific indications. However, atrial fibrillation (which is often clinically silent and unrecognised) is common after the procedure and embolic material often thrombin-rich. Recent evidence has therefore questioned this approach, suggesting that DAPT may be futile compared with aspirin alone and that OAC could be a relevant alternative. Future randomised and appropriately powered trials comparing different regimens of antithrombotic therapy, including new antiplatelet and anticoagulant agents, are warranted to increase the available evidence on this topic and create appropriate recommendations for this frail population. Meanwhile, it remains rational to adhere to current guidelines, with routine DAPT and recourse to OAC when specifically indicated, whilst always tailoring therapy on the basis of individual bleeding and thromboembolic risk.

Stroke, coronary and peripheral artery disease survey on antithrombotic treatment (START IT)

QUESTIONS UNDER STUDY: To determine the perception of primary care physicians regarding the risk of subsequent atherothrombotic events in patients with established cardiovascular (CV) disease, and to correlate this perception with documented antithrombotic therapy. METHODS: In a cross-sectional study of the general practice population in Switzerland, 381 primary care physicians screened 127 040 outpatients during 15 consecutive workdays in 2006. Perception of subsequent atherothrombotic events in patients with established CV disease was assessed using a tick box questionnaire allowing choices between low, moderate, high or very high risk. Logistic regression models were used to determine the relationship between risk perception and antithrombotic treatment. RESULTS: Overall, 13 057 patients (10.4%) were identified as having established CV disease and 48.8% of those were estimated to be at high to very high risk for subsequent atherothrombotic events. Estimated higher risk for subsequent atherothrombotic events was associated with a shift from aspirin monotherapy to clopidogrel, vitamin K antagonist or aspirin plus clopidogrel (p <0.001 for trend). Clopidogrel (12.7% vs 6.8%, p <0.001), vitamin K antagonist (24.5% vs 15.6%, p <0.001) or aspirin plus clopidogrel (10.2% vs 4.2%, p <0.001) were prescribed in patients estimated to be at high to very high risk more often than in those at low to moderate risk. CONCLUSIONS: Perception of primary care physicians regarding risk of subsequent atherothrombotic events varies in patients with CV disease, and as a result antithrombotic therapy is altered in patients with anticipated high to very high risk even though robust evidence and clear guidelines are lacking.

Mechanical antithrombotic intervention by LAA occlusion in atrial fibrillation

Stroke in patients with atrial fibrillation (AF) is often associated with substantial morbidity and mortality. Oral anticoagulation remains the first-line approach to stroke prevention in such individuals; however, for a considerable proportion of patients, traditional treatment using warfarin is limited by a number of factors, such as the inconvenience of frequent therapeutic monitoring and the risk of haemorrhage. The development of new oral anticoagulants with improved efficacy and safety profiles has provided viable options for oral anticoagulation therapy in patients with nonvalvular (nonrheumatic AF). Nonetheless, in patients who have an increased risk of major haemorrhage, a nonpharmacological approach to antithrombotic therapy remains an attractive alternative. The left atrial appendage (LAA) has been found to be the source of >90% of thrombi in patients with nonvalvular AF; thus, prevention of thrombus formation via transcatheter mechanical LAA occlusion is a novel therapeutic target for stroke prevention in this patient population. In this Review, we present the rationale for LAA occlusion in patients with AF, the available occlusion devices and their clinical evidence to date. We also discuss the roles of various imaging techniques in device implantation and the management strategy for associated procedural complications.

Atrial fibrillation in congestive heart failure

Atrial fibrillation (AF) and heart failure (HF) are common and interrelated conditions, each promoting the other, and both associated with increased mortality. HF leads to structural and electrical atrial remodeling, thus creating the basis for the development and perpetuation of AF; and AF may lead to hemodynamic deterioration and the development of tachycardia-mediated cardiomyopathy. Stroke prevention by antithrombotic therapy is crucial in patients with AF and HF. Of the 2 principal therapeutic strategies to treat AF, rate control and rhythm control, neither has been shown to be superior to the other in terms of survival, despite better survival in patients with sinus rhythm compared with those in AF. Antiarrhythmic drug toxicity and poor efficacy are concerns. Catheter ablation of AF can establish sinus rhythm without the risks of antiarrhythmic drug therapy, but has important procedural risks, and data from randomized trials showing a survival benefit of this treatment strategy are still lacking. In intractable cases, ablation of the atrioventricular junction and placement of a permanent pacemaker is a treatment alternative; and biventricular pacing may prevent or reduce the negative consequences of chronic right ventricular pacing.

Chapter VI: Follow-up after revascularisation

Structured follow-up after revascularisation for chronic critical limb ischaemia (CLI) aims at sustained treatment success and continued best patient care. Thereby, efforts need to address three fundamental domains: (A) best medical therapy, both to protect the arterial reconstruction locally and to reduce atherosclerotic burden systemically; (B) surveillance of the arterial reconstruction; and (C) timely initiation of repeat interventions. As most CLI patients are elderly and frail, sustained resolution of CLI and preserved ambulatory capacity may decide over independent living and overall prognosis. Despite this importance, previous guidelines have largely ignored follow-up after CLI; arguably because of a striking lack of evidence and because of a widespread assumption that, in the context of CLI, efficacy of initial revascularisation will determine prognosis during the short remaining life expectancy. This chapter of the current CLI guidelines aims to challenge this disposition and to recommend evidentially best clinical practice by critically appraising available evidence in all of the above domains, including antiplatelet and antithrombotic therapy, clinical surveillance, use of duplex ultrasound, and indications for and preferred type of repeat interventions for failing and failed reconstructions. However, as corresponding studies are rarely performed among CLI patients specifically, evidence has to be consulted that derives from expanded patient populations. Therefore, most recommendations are based on extrapolations or subgroup analyses, which leads to an almost systematic degradation of their strength. Endovascular reconstruction and surgical bypass are considered separately, as are specific contexts such as diabetes or renal failure; and critical issues are highlighted throughout to inform future studies.

[Vasculitis as a reason of chronic headache]

A 13-year-old girl presented to our emergency with a one week history of fever and skin rash and new onset of chorea for the last three days. There was a long standing history of right predominant headache; followed by personality change, fatigue, arthralgia and weight loss over the last few months. Previous investigations by head CT and ophthalmological examination did not explain the symptoms. Further investigations revealed peri- and pancarditis with aortic insufficiency, a renal involvement with elevated creatinin, protein- and hematuria and a hemolytic anemia. Diagnosis of lupus eythematodes was confirmed by high ANA, anti-dsDNS and Anticardiolipin antibodies. Within the first 48 hours after admission there was significant deterioration with reduced vigilance and dysarthria. MRI of the brain and dopplersonography of cerebral vessels showed a complete thrombosis of the right medial cerebral artery with a small net of collaterals, irregularities of the left cerebral artery due to vasculitis and several subacute leftsided ischemias. Immunosuppressive therapy with high-dose corticosteroids and cyclophosphamid together with antithrombotic therapy induced an improvement of neurologic, renal and cardiac function.

Clinical impact of gastrointestinal bleeding in patients undergoing percutaneous coronary interventions.

BACKGROUND The risk factors and clinical sequelae of gastrointestinal bleeding (GIB) in the current era of drug-eluting stents, prolonged dual antiplatelet therapy, and potent P2Y12 inhibitors are not well established. We determined the frequency, predictors, and clinical impact of GIB after percutaneous coronary interventions (PCIs) in a contemporary cohort of consecutive patients treated with unrestricted use of drug-eluting stents. METHODS AND RESULTS Between 2009 and 2012, all consecutive patients undergoing PCI were prospectively included in the Bern PCI Registry. Bleeding Academic Research Consortium (BARC) GIB and cardiovascular outcomes were recorded within 1 year of follow-up. Among 6212 patients, 84.1% received new-generation drug-eluting stents and 19.5% received prasugrel. At 1 year, GIB had occurred in 65 patients (1.04%); 70.8% of all events and 84.4% of BARC ≥3B events were recorded >30 days after PCI. The majority of events (64.4%) were related to upper GIB with a more delayed time course compared with lower GIB. Increasing age, previous GIB, history of malignancy, smoking, and triple antithrombotic therapy (ie, oral anticoagulation plus dual antiplatelet therapy) were independent predictors of GIB in multivariable analysis. GIB was associated with increased all-cause mortality (adjusted hazard ratio, 3.40; 95% confidence interval, 1.67-6.92; P=0.001) and the composite of death, myocardial infarction, or stroke (adjusted hazard ratio, 3.75; 95% confidence interval, 1.99-7.07; P<0.001) and was an independent predictor of all-cause mortality during 1 year. CONCLUSIONS Among unselected patients undergoing PCI, GIB has a profound effect on prognosis. Triple antithrombotic therapy emerged as the single drug-related predictor of GIB in addition to patient-related risk factors within 1 year of PCI. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT02241291.

Thrombus formation in the left ventricle after large myocardial infarction – assessment with cardiac magnetic resonance imaging

INTRODUCTION Left ventricular thrombus (LVT) formation may worsen the post-infarct outcome as a result of thromboembolic events. It also complicates the use of modern antiplatelet regimens, which are not compatible with long-term oral anticoagulation. The knowledge of the incidence of LVT may therefore be of importance to guide antiplatelet and antithrombotic therapy after acute myocardial infarction (AMI). METHODS In 177 patients with large, mainly anterior AMI, standard cardiac magnetic resonance imaging (CMR) including cine and late gadolinium enhancement (LGE) imaging was performed shortly after AMI as per protocol. CMR images were analysed at an independent core laboratory blinded to the clinical data. Transthoracic echocardiography (TTE) was not mandatory for the trial, but was performed in 64% of the cases following standard of care. In a logistic model, 3 out of 61 parameters were used in a multivariable model to predict LVT. RESULTS LVT was detected by use of CMR in 6.2% (95% confidence interval [CI] 3.1%-10.8%). LGE sequences were best to detect LVT, which may be missed in cine sequences. We identified body mass index (odds ratio 1.18; p = 0.01), baseline platelet count (odds ratio 1.01, p = 0.01) and infarct size as assessed by use of CMR (odds ratio 1.03, p = 0.02) as best predictors for LVT. The agreement between TTE and CMR for the detection of LVT is substantial (kappa = 0.70). DISCUSSION In the current analysis, the incidence of LVT shortly after AMI is relatively low, even in a patient population at high risk. An optimal modality for LVT detection is LGE-CMR but TTE has an acceptable accuracy when LGE-CMR is not available.

Developing drugs for use before, during and soon after percutaneous coronary intervention.

INTRODUCTION Percutaneous coronary intervention (PCI) is a milestone for treating coronary artery disease (CAD). Antithrombotic therapy is essential to prevent ischemic complications, including the microvascular no-reflow, while minimizing bleeding events. Areas covered: This overview discusses available and developing drugs for PCI including anticoagulants, antiplatelets and treatment of no-reflow. Expert opinion: For years unfractionated heparin (UFH) has been the unique anticoagulant to be used before and during PCI. Enoxaparin showed similar efficacy and safety, yet, based on recent trials, bivalirudin has been shown to have some benefits, particularly for patients with ST-segment elevation myocardial infarction (STEMI). The evidence concerning new anticoagulants is still preliminary, except for new oral anticoagulants, particularly rivaroxaban that showed intriguing findings and is currently under investigation. Dual antiplatelet therapy (DAPT) is the standard of care after PCI, but new developments have recently emerged. Indeed, ticagrelor and prasugrel are currently recommended over clopidogrel due to their significant reduction of ischemic events in acute coronary syndrome (ACS) whereas clopidogrel remains the choice in stable CAD. Among new agents, vorapaxar and cangrelor showed positive but limited evidence and might be considered at least in selected patients. Conversely, evidence on effective treatments for no-reflow remains limited and would require future dedicated research.

A Synthetic Factor XIIa Inhibitor Blocks Selectively Intrinsic Coagulation Initiation.

Coagulation factor XII (FXII) inhibitors are of interest for the study of the protease in the intrinsic coagulation pathway, for the suppression of contact activation in blood coagulation assays, and they have potential application in antithrombotic therapy. However, synthetic FXII inhibitors developed to date have weak binding affinity and/or poor selectivity. Herein, we developed a peptide macrocycle that inhibits activated FXII (FXIIa) with an inhibitory constant Ki of 22 nM and a selectivity of >2000-fold over other proteases. Sequence and structure analysis revealed that one of the two macrocyclic rings of the in vitro evolved peptide mimics the combining loop of corn trypsin inhibitor, a natural protein-based inhibitor of FXIIa. The synthetic inhibitor blocked intrinsic coagulation initiation without affecting extrinsic coagulation. Furthermore, the peptide macrocycle efficiently suppressed plasma coagulation triggered by contact of blood with sample tubes and allowed specific investigation of tissue factor initiated coagulation.

Long-term ticagrelor monotherapy versus standard dual antiplatelet therapy followed by aspirin monotherapy in patients undergoing biolimus-eluting stent implantation: rationale and design of the GLOBAL LEADERS trial

AIMS The GLOBAL LEADERS trial is a superiority study in patients undergoing percutaneous coronary intervention, with a uniform use of Biolimus A9-eluting stents (BES) and bivalirudin. GLOBAL LEADERS was designed to assess whether a 24-month antithrombotic regimen with ticagrelor and one month of acetylsalicylic acid (ASA), compared to conventional dual antiplatelet therapy (DAPT), improves outcomes. METHODS AND RESULTS Patients (n >16,000) are randomised (1:1 ratio) to ticagrelor 90 mg twice daily for 24 months plus ASA ≤100 mg for one month versus DAPT with either ticagrelor (acute coronary syndrome) or clopidogrel (stable coronary artery disease) for 12 months plus ASA ≤100 mg for 24 months. The primary outcome is a composite of all-cause mortality or non-fatal, new Q-wave myocardial infarction at 24 months. The key safety endpoint is investigator-reported class 3 or 5 bleeding according to the Bleeding Academic Research Consortium (BARC) definitions. Sensitivity analysis will be carried out to explore potential differences in outcome across geographic regions and according to specific angiographic and clinical risk estimates. CONCLUSIONS The GLOBAL LEADERS trial aims to assess the role of ticagrelor as a single antiplatelet agent after a short course of DAPT for the long-term prevention of cardiac adverse events, across a wide spectrum of patients, following BES implantation.

Anticoagulant vs. antiplatelet therapy in patients with cryptogenic stroke and patent foramen ovale: an individual participant data meta-analysis.

AIMS The preferred antithrombotic strategy for secondary prevention in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO) is unknown. We pooled multiple observational studies and used propensity score-based methods to estimate the comparative effectiveness of oral anticoagulation (OAC) compared with antiplatelet therapy (APT). METHODS AND RESULTS Individual participant data from 12 databases of medically treated patients with CS and PFO were analysed with Cox regression models, to estimate database-specific hazard ratios (HRs) comparing OAC with APT, for both the primary composite outcome [recurrent stroke, transient ischaemic attack (TIA), or death] and stroke alone. Propensity scores were applied via inverse probability of treatment weighting to control for confounding. We synthesized database-specific HRs using random-effects meta-analysis models. This analysis included 2385 (OAC = 804 and APT = 1581) patients with 227 composite endpoints (stroke/TIA/death). The difference between OAC and APT was not statistically significant for the primary composite outcome [adjusted HR = 0.76, 95% confidence interval (CI) 0.52-1.12] or for the secondary outcome of stroke alone (adjusted HR = 0.75, 95% CI 0.44-1.27). Results were consistent in analyses applying alternative weighting schemes, with the exception that OAC had a statistically significant beneficial effect on the composite outcome in analyses standardized to the patient population who actually received APT (adjusted HR = 0.64, 95% CI 0.42-0.99). Subgroup analyses did not detect statistically significant heterogeneity of treatment effects across clinically important patient groups. CONCLUSION We did not find a statistically significant difference comparing OAC with APT; our results justify randomized trials comparing different antithrombotic approaches in these patients.