Frantisek Kovar

RUBY-1: a randomized, double-blind, placebo-controlled trial of the safety and tolerability of the novel oral factor Xa inhibitor darexaban (YM150) following acute coronary syndrome

Aims To establish the safety, tolerability and most promising regimen of darexaban (YM150), a novel, oral, direct factor Xa inhibitor, for prevention of ischaemic events in acute coronary syndrome (ACS). Methods In a 26-week, multi-centre, double-blind, randomized, parallel-group study, 1279 patients with recent high-risk non-ST-segment or ST-segment elevation ACS received one of six darexaban regimens: 5 mg b.i.d., 10 mg o.d., 15 mg b.i.d., 30 mg o.d., 30 mg b.i.d., or 60 mg o.d. or placebo, on top of dual antiplatelet treatment. Primary outcome was incidence of major or clinically relevant non-major bleeding events. The main efficacy outcome was a composite of death, stroke, myocardial infarction, systemic thromboembolism, and severe recurrent ischaemia. Results Bleeding rates were numerically higher in all darexaban arms vs. placebo (pooled HR: 2.275; 95% CI: 1.13–4.60, P = 0.022). Using placebo as reference (bleeding rate 3.1%), there was a dose–response relationship (P = 0.009) for increased bleeding with increasing darexaban dose (6.2, 6.5, and 9.3% for 10, 30, and 60 mg daily, respectively), which was statistically significant for 30 mg b.i.d. (P = 0.002). There was no decrease (indeed a numerical increase in the 30 and 60 mg dose arms) in efficacy event rates with darexaban, but the study was underpowered for efficacy. Darexaban showed good tolerability without signs of liver toxicity. Conclusions Darexaban when added to dual antiplatelet therapy after ACS produces an expected dose-related two- to four-fold increase in bleeding, with no other safety concerns but no signal of efficacy. Establishing the potential of low-dose darexaban in preventing major cardiac events after ACS requires a large phase III trial. ClinicalTrials.gov Identifier: NCT00994292

Effect of losmapimod on cardiovascular outcomes in patients hospitalized with acute myocardial infarction: A randomized clinical trial

IMPORTANCE p38 Mitogen-activated protein kinase (MAPK)-stimulated inflammation is implicated in atherogenesis, plaque destabilization, and maladaptive processes in myocardial infarction (MI). Pilot data in a phase 2 trial in non-ST elevation MI indicated that the p38 MAPK inhibitor losmapimod attenuates inflammation and may improve outcomes. OBJECTIVE To evaluate the efficacy and safety of losmapimod on cardiovascular outcomes in patients hospitalized with an acute myocardial infarction. DESIGN, SETTING, AND PATIENTS LATITUDE-TIMI 60, a randomized, placebo-controlled, double-blind, parallel-group trial conducted at 322 sites in 34 countries from June 3, 2014, until December 8, 2015. Part A consisted of a leading cohort (n = 3503) to provide an initial assessment of safety and exploratory efficacy before considering progression to part B (approximately 22,000 patients). Patients were considered potentially eligible for enrollment if they had been hospitalized with an acute MI and had at least 1 additional predictor of cardiovascular risk. INTERVENTIONS Patients were randomized to either twice-daily losmapimod (7.5 mg; n = 1738) or matching placebo (n = 1765) on a background of guideline-recommended therapy. Patients were treated for 12 weeks and followed up for an additional 12 weeks. MAIN OUTCOMES AND MEASURES The primary end point was the composite of cardiovascular death, MI, or severe recurrent ischemia requiring urgent coronary revascularization with the principal analysis specified at week 12. RESULTS In part A, among the 3503 patients randomized (median age, 66 years; 1036 [29.6%] were women), 99.1% had complete ascertainment for the primary outcome. The primary end point occurred by 12 weeks in 123 patients treated with placebo (7.0%) and 139 patients treated with losmapimod (8.1%; hazard ratio, 1.16; 95% CI, 0.91-1.47; P = .24). The on-treatment rates of serious adverse events were 16.0% with losmapimod and 14.2% with placebo. CONCLUSIONS AND RELEVANCE Among patients with acute MI, use of losmapimod compared with placebo did not reduce the risk of major ischemic cardiovascular events. The results of this exploratory efficacy study did not justify proceeding to a larger efficacy trial in the existing patient population. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT02145468.

Anticoagulation With Otamixaban and Ischemic Events in Non–ST-Segment Elevation Acute Coronary Syndromes: The TAO Randomized Clinical Trial

IMPORTANCE The optimal anticoagulant for patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) managed with an invasive strategy remains controversial. OBJECTIVE To compare the clinical efficacy and safety of otamixaban, a novel intravenous direct factor Xa inhibitor, with that of unfractionated heparin plus downstream eptifibatide in patients with NSTE-ACS undergoing a planned early invasive strategy. DESIGN, SETTING, AND PARTICIPANTS Randomized, double-blind, active-controlled superiority trial that enrolled 13,229 patients with NSTE-ACS and a planned early invasive strategy, at 568 active sites in 55 countries and conducted between April 2010 and February 2013. A planned interim analysis was conducted for otamixaban dose selection. INTERVENTIONS Eligible participants were randomized to otamixaban (bolus and infusion, at 1 of 2 doses) or unfractionated heparin plus, at the time of percutaneous coronary intervention, eptifibatide. The otamixaban dose selected at interim analysis was an intravenous bolus of 0.080 mg/kg followed by an infusion of 0.140 mg/kg per hour. MAIN OUTCOMES AND MEASURES The primary efficacy outcome was the composite of all-cause death or new myocardial infarction through day 7. RESULTS Rates of the primary efficacy outcome were 5.5% (279 of 5105 patients) randomized to receive otamixaban and 5.7% (310 of 5466 patients) randomized to receive unfractionated heparin plus eptifibatide (adjusted relative risk, 0.99 [95% CI, 0.85-1.16]; P = .93). There were no differences for the secondary end points, including procedural thrombotic complications. The primary safety outcome of Thrombosis in Myocardial Infarction major or minor bleeding through day 7 was increased by otamixaban (3.1% vs 1.5%; relative risk, 2.13 [95% CI, 1.63-2.78]; P < .001). Results were consistent across prespecified subgroups. CONCLUSIONS AND RELEVANCE Otamixaban did not reduce the rate of ischemic events relative to unfractionated heparin plus eptifibatide but did increase bleeding. These findings do not support the use of otamixaban for patients with NSTE-ACS undergoing planned early percutaneous coronary intervention. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01076764.

First Evidence: TRAP-Induced Platelet Aggregation Is Reduced in Patients Receiving Xabans:

The availability of direct oral anticoagulants has caused a paradigm shift in the management of thrombosis. Rivaroxaban and apixaban are 2 direct oral anticoagulants whose target specificity is activated factor X (FXa). However, it is still not fully understood if and how xabans impact platelet function. This observational study aimed to assess the in vitro platelet function in patients with atrial fibrillation receiving xabans. This was a single-center study quantifying platelet aggregation in 41 patients treated with apixaban or rivaroxaban by light transmission aggregometry. The thrombin receptor activating peptide (TRAP)-induced platelet aggregation was significantly lower 2 hours after taking rivaroxaban or apixaban compared to baseline value (56.15% [8.53%] vs 29.51% [12.9%]; P = .000). Moreover, concomitant use of angiotensin-converting enzyme blockers, proton pump inhibitors, and statins reduces the efficiency of xabans. The TRAP-induced platelet aggregation was reduced in patients with cardiovascular disease 2 hours after receiving xabans.

Role of VASP Phosphorylation Assay in Monitoring the Antiplatelet Therapy

Abstract Dual antiplatelet treatment with clopidogrel and aspirin represents standard regimen in prevention of thromboembolic events in patients with ischemic heart disease undergoing percutaneous coronary intervention (PCI). One of the greatest pitfalls of clopidogrel treatment is large inter-individual variability in response. Large amount of patients does not respond adequately and therefore are not „protected“ even in spite of receiving the therapy. Poor responders are exposed to three-fold increased risk of myocardial infarction, stent thrombosis and cardiac death. Clopidogrel is an antiplatelet prodrug, whose active metabolite inhibits platelet function by irreversible binding to the (adenosine diphosphate) platelet receptor P2Y12. Receptor P2Y12 plays primal role in ADP-mediated platelet activation, and also in mechanism of action of ADP inhibitors such as clopidogrel, prasugrel etc. Reasons stated above, raised the necessity for implementing reliable laboratory test in order to identify the unprotected patients. In an ideal scenario, such test would serve to adjust the dose and guide the individual tailored treatment. Vasodilator Stimulated Phosphoprotein (VASP) is an intracellular platelet protein which is non phosphorylated at basal state. Since its relation in cascade with P2Y12 receptor, VASP phosphorylation corerlates with inhibition of P2Y12 which is the receptor of prime importance in ADP mediated activation of platelets and as is primary target of ADP inhibitors action. Outcome of the assay is represented as the value of platelet reactivity index (PRI), where PRI values above 50% are considered inadequate response to treatment and signal exposure to increased risk of myocardial infarction, post-PCI stent thrombosis and cardiac death. VASP-P flow cytometric assay is emerging into the spotlight as the promising method, mostly for its specificity for ADP inhibitors, better outlook for standardising results and lesser sample manipulation compared to multiple electrode aggregometry.

Outcomes of Patients with Newly Diagnosed Cardiac Myxoma: A Retrospective Multicentric Study

The patient database at the First Department of Internal Medicine in Martin, the Central Slovak Institute for Cardiac and Vascular Diseases in Banska Bystrica, and the National Slovak Institute of Cardiovascular Diseases in Bratislava was searched to identify patients with benign tumors of the heart seen during the 5-year period between 2011 and 2016. Forty-one patients with primary cardiac myxomas were identified and their medical records were reviewed for details pertaining to presenting symptoms, staging modalities, treatment approaches, and outcomes. Most of the studied patients were diagnosed with echocardiography (n = 35, 85%). The occurrence of the tumor was higher in the female population (n = 25, 61%). The most common presenting symptoms were dyspnoea (n = 17, 42%), chest pain (n = 3, 7%), or pain and paraesthesia of the limbs (n = 2, 5%). Acute embolic event due to embolization of tumor fragments resulted in cerebral stroke (n = 5, 12%). All patients were treated by resection. Only one comorbid patient died due to multiple-organ dysfunction syndrome two weeks after the resection. The most common postoperative complication was bleeding (n = 2, 5%) and infection (n = 2, 5%). The early diagnosis and appropriate treatment are often curative, with very low risk of recurrence. Postoperative survival is high.

Review of the Pharmacology of the Emerging Possibilities of the Direct Oral Anticoagulants' Reversal

BACKGROUND Direct oral anticoagulants (DOACs) offer consistent and predictable anticoagulation, oral administration with good patient compliance and a good safety profile. Dabigatran - a direct thrombin inhibitor, apixaban and rivaroxaban - direct factor Xa inhibitors are now largely used for anticoagulation in patients with nonvalvular atrial fibrillation and in patients with venous thromboembolism. These agents have emerged as an expediential clinical choice in long-term anticoagulation for an increasing number of patients. Despite their advantages, concerns persist about a lack of rapid reversal agents in urgent clinical situations. METHODS This review is focused on the pharmacology of nonspecific and target-specific reversal agents for DOACs-induced anticoagulation. A systemic review of preclinical and clinical studies published in peer-reviewed scientific journals was performed. RESULTS AND CONCLUSIONS Fresh frozen plasma and coagulation factors concentrates might be considered in bleeding emergencies; however, there is a lack of larger studies confirming the efficacy of coagulation factors concentrates for the reversal of DOACs-induced anticoagulation, and a particular risk of coagulation factors concentrates-induced thrombosis. Recently, idarucizumab has been approved commercially for acute reversal of dabigatran in emergencies as a first target-specific reversal agent. Moreover, andexanet alpha and aripazine are being extensively studied in several phase II and III clinical studies. It is likely that more target-specific agents for reversal of DOACs-induced anticoagulation will be introduced to clinical practice in near future.

Contrast-Induced Nephropathy: Risk Factors, Clinical Implication, Diagnostics Approach, Prevention

Contrast induced nephropathy (CIN) is an important and well‐known complication in pa‐ tients with chronic renal insufficiency undergoing both coronary angiography and coronary interventions. The estimated incidence of CN after coronary angiography was around 15%. In fact, CIN is the third leading cause of acute renal failure in hospitalized patients [1]. CIN is usually transient disorder, but in some cases may result in residual permanent renal dam‐ age, prolong hospital stay and increase medical cost [2]. Renal failure increases the risk of developing severe nonrenal complications that can lead to death. The mortality rate in sub‐ jects without renal failure was 7%, compared with 34% in patients with renal failure [3]. With the increasing number of patients undergoing percutaneous coronary intervention, it is expected that the burden of such iatrogenic complications will exponentially increase and effective preventive measures are necessary.

Risk Stratification and Invasive Strategy in NSTE-ACS

Under the heading of acute coronary syndrome (ACS), we include myocardial infarction with ST segment elevation (STEMI), myocardial infarction without ST segment elevation (NSTEMI) and unstable angina (UA). Given the similar pathophysiological mechanisms, clinical manifestations, diagnostic and therapeutic algorithm UA and NSTEMI are sorted into a common group of ACS without ST segment elevation (NSTE-ACS). ACS is a serious clinical disease, which is associated with higher mortality than stable angina pectoris. High proportion of patients die of sudden death in the early hours of ACS (especially STEMI), before admission to the hospital, therefore it is difficult to assess the real incidence of ACS. The incidence of ACS also depends on the sensitivity of the humoral markers of myocyte necrosis. The annual hospital admissions rate for NSTE-ACS is estimated from the results of registers and surveys about 3 per 1000 inhabitants. The proportion of STEMI represents approximately 20% of NSTE ACS.