Efficacy and safety of tenecteplase in combination with the low-molecular-weight heparin enoxaparin or unfractionated heparin in the prehospital setting: the Assessment of the Safety and Efficacy of a New Thrombolytic Regimen (ASSENT)-3 PLUS randomized trial in acute myocardial infarction

Tenecteplase Catheter-Directed Thrombolytic Therapy in Submassive Pulmonary Embolism: A Case Report

Introduction: In pulmonary embolism (PE), when used for catheter-directed thrombolysis (CDT), low-dose alteplase is associated with good outcomes. Tenecteplase has been only used as intravenous for this indication. In the context of our national economic crisis where alteplase was unavailable, we describe our experience with tenecteplase CDT. Case: A 73-year-old male, hypertensive and smoker with COPD, presented to the ED with intermediate high-risk PE.(ED) with intermediate high-risk PE. Heparin infusion was initiated. A few hours later, the patient developed atrial fibrillation (AF) for which amiodarone infusion was started. Also, a left femoral and popliteal vein thrombosis was also confirmed by the lower extremity duplex. As the patient remained dyspneic with unstable vital signs, the decision was to perform a CDT. In the absence of alteplase, tenecteplase was used at 0.5 mg/h over 30 h, for a total of 15 mg. Result: Twenty-four hours after tenecteplase initiation, dyspnea and vital signs had significantly improved. Oxygen support was gradually dropping to finally stop. Being on concomitant heparin infusion, the patient had a mild blood oozing at the femoral vein site of entry; however, this did not require any transfusion or discontinuation of heparin. The patient regained his baseline physical and mental functions and was discharged on enoxaparin and amiodarone tablet. Discussion: This is the first experience describing the use of tenecteplase as part of CDT in a patient with acute intermediate high-risk PE. The combination to therapeutic heparin infusion, already described in different clinical scenarios with intravenous tenecteplase, was safe and well tolerated Conclusion: CDT with tenecteplase was, for the first time, safely and effectively used in an intermediate high-risk PE patient. However, more studies are needed to confirm and establish these findings.

Characterization of myocardial injury phenotype by thermal liquid biopsy

Background and aims

With the advent and implementation of high-sensitivity cardiac troponin assays, differentiation of patients with distinct types of myocardial injuries, including acute thrombotic myocardial infarction (TMI), acute non-thrombotic myocardial injury (nTMi), and chronic coronary atherosclerotic disease (cCAD), is of pressing clinical importance. Thermal liquid biopsy (TLB) emerges as a valuable diagnostic tool, relying on identifying thermally induced conformational changes of biomolecules in blood plasma. While TLB has proven useful in detecting and monitoring several cancers and autoimmune diseases, its application in cardiovascular diseases remains unexplored. In this proof-of-concept study, we sought to determine and characterize TLB profiles in patients with TMI, nTMi, and cCAD at multiple acute-phase time points (T 0 h, T 2 h, T 4 h, T 24 h, T 48 h) as well as a follow-up time point (Tfu) when the patient was in a stable state.

Methods

TLB profiles were collected for 115 patients (60 with TMI, 35 with nTMi, and 20 with cCAD) who underwent coronary angiography at the event presentation and had subsequent follow-up. Medical history, physical, electrocardiographic, histological, biochemical, and angiographic data were gathered through medical records, standardized patient interviews, and core laboratory measurements.

Results

Distinctive signatures were noted in the median TLB profiles across the three patient types. TLB profiles for TMI and nTMi patients exhibited gradual changes from T0 to Tfu, with significant differences during the acute and quiescent phases. During the quiescent phase, all three patient types demonstrated similar TLB signatures. An unsupervised clustering analysis revealed a unique TLB signature for the patients with TMI. TLB metrics generated from specific features of TLB profiles were tested for differences between patient groups. The first moment temperature (TFM) metric distinguished all three groups at time of presentation (T0). In addition, 13 other TLB-derived metrics were shown to have distinct distributions between patients with TMI and those with cCAD.

Conclusion

Our findings demonstrated the use of TLB as a sensitive and data-rich technique to be explored in cardiovascular diseases, thus providing valuable insight into acute myocardial injury events.

STREAM-2: Half-Dose Tenecteplase or Primary Percutaneous Coronary Intervention in Older Patients With ST-Segment-Elevation Myocardial Infarction: A Randomized, Open-Label Trial

BACKGROUND

ST-segment-elevation myocardial infarction (STEMI) guidelines recommend pharmaco-invasive treatment if timely primary percutaneous coronary intervention (PCI) is unavailable. Full-dose tenecteplase is associated with an increased risk of intracranial hemorrhage in older patients. Whether pharmaco-invasive treatment with half-dose tenecteplase is effective and safe in older patients with STEMI is unknown.

METHODS

STREAM-2 (Strategic Reperfusion in Elderly Patients Early After Myocardial Infarction) was an investigator-initiated, open-label, randomized, multicenter study. Patients ≥60 years of age with ≥2 mm ST-segment elevation in 2 contiguous leads, unable to undergo primary PCI within 1 hour, were randomly assigned (2:1) to half-dose tenecteplase followed by coronary angiography and PCI (if indicated) 6 to 24 hours after randomization, or to primary PCI. Efficacy end points of primary interest were ST resolution and the 30-day composite of death, shock, heart failure, or reinfarction. Safety assessments included stroke and nonintracranial bleeding.

RESULTS

Patients were assigned to pharmaco-invasive treatment (n=401) or primary PCI (n=203). Median times from randomization to tenecteplase or sheath insertion were 10 and 81 minutes, respectively. After last angiography, 85.2% of patients undergoing pharmaco-invasive treatment and 78.4% of patients undergoing primary PCI had ≥50% resolution of ST-segment elevation; their residual median sums of ST deviations were 4.5 versus 5.5 mm, respectively. Thrombolysis In Myocardial Infarction flow grade 3 at last angiography was ≈87% in both groups. The composite clinical end point occurred in 12.8% (51/400) of patients undergoing pharmaco-invasive treatment and 13.3% (27/203) of patients undergoing primary PCI (relative risk, 0.96 [95% CI, 0.62-1.48]). Six intracranial hemorrhages occurred in the pharmaco-invasive arm (1.5%): 3 were protocol violations (excess anticoagulation in 2 and uncontrolled hypertension in 1). No intracranial bleeding occurred in the primary PCI arm. The incidence of major nonintracranial bleeding was low in both groups (<1.5%).

CONCLUSIONS

Halving the dose of tenecteplase in a pharmaco-invasive strategy in this early-presenting, older STEMI population was associated with electrocardiographic changes that were at least comparable to those after primary PCI. Similar clinical efficacy and angiographic end points occurred in both treatment groups. The risk of intracranial hemorrhage was higher with half-dose tenecteplase than with primary PCI. If timely PCI is unavailable, this pharmaco-invasive strategy is a reasonable alternative, provided that contraindications to fibrinolysis are observed and excess anticoagulation is avoided.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02777580.

The empirical estimate of the survival and variance using a weighted composite endpoint

BACKGROUND

Composite endpoints for estimating treatment efficacy are routinely used in several therapeutic areas and have become complex in the number and types of component outcomes included. It is assumed that its components are of similar asperity and chronology between both treatment arms as well as uniform in magnitude of the treatment effect. However, these assumptions are rarely satisfied. Understanding this heterogeneity is important in developing a meaningful assessment of the treatment effect.

METHODS

We developed the Weighted Composite Endpoint (WCE) method which uses weights derived from stakeholder values for each event type in the composite endpoint. The derivation for the product limit estimator and the variance of the estimate are presented. The method was then tested using data simulated from parameters based on a large cardiovascular trial. Variances from the estimated and traditional approach are compared through increasing sample size.

RESULTS

The WCE method used all of the events through follow-up and generated a multiple recurrent event survival. The treatment effect was measured as the difference in mean survivals between two treatment arms and corresponding 95% confidence interval, providing a less conservative estimate of survival and variance, giving a higher survival with a narrower confidence interval compared to the traditional time-to-first-event analysis.

CONCLUSIONS

The WCE method embraces the clinical texture of events types by incorporating stakeholder values as well as all events during follow-up. While the effective number of events is lower in the WCE analysis, the reduction in variance enhances the ability to detect a treatment effect in clinical trials.

The Evolution of Anticoagulation for Percutaneous Coronary Intervention: A 40-Year Journey

The selection of antithrombotic strategies continue to be of utmost importance during percutaneous coronary intervention (PCI) and have evolved over the past 40 years. Although the backbone of therapy during PCI continues to be a combination of oral antiplatelets and parenteral anticoagulants, a variety of different approaches have been tested over time. In particular, different choices of anticoagulation management have been tested in the stable ischemic heart disease and acute coronary syndrome setting. Evaluation of alternative regimens in the quest to balance ischemic and bleeding risk have undoubtedly improved patient care with PCI. In the current review we highlight the evolution of evidence-based therapeutic options over the past 40 years from the beginning of coronary angioplasty to contemporary PCI. We provide insight into future therapeutic options and provide a contemporary overview of anticoagulation choices for patients who require PCI on the basis of up-to-date evidence balancing ischemic and bleeding risk and according to clinical presentation.

Primary Percutaneous Coronary Intervention and Application of the Pharmacoinvasive Approach Within ST-Elevation Myocardial Infarction Care Networks

The management of acute ST-elevation myocardial infarction (STEMI) has transitioned from observation and reactive treatment of hemodynamic and arrhythmic complications to accelerated reperfusion and application of evidence-based treatment to minimize morbidity and mortality. International research established the importance of timely reperfusion therapy and the application of fibrinolysis, primary percutaneous coronary intervention (PCI), and subsequent development of the pharmacoinvasive approach. Clinician thought leaders developed and investigated comprehensive systems of care to optimize the outcomes of patients with STEMI, with a key focus in Canada being the integration of prehospital paramedics in diagnosis, triage, and treatment. This article will review highlights of these interventions and identify future challenges and opportunities in STEMI patient care.

Diagnosis and management of acute coronary syndromes

Acute coronary syndromes are a significant cause of morbidity and mortality in Australia. Outcomes are likely to be improved by rapid and accurate diagnosis, and early intervention

The development of high-sensitivity troponin assays has revealed previously unrecognised types of myocardial injury, for which conventional management guidelines for myocardial infarction may not confer similar benefits. The distinction between myocardial injury and myocardial infarction has therefore become increasingly important

Once the diagnosis of acute myocardial infarction has been made, individualised acute reperfusion strategies including percutaneous coronary intervention or fibrinolytic therapy should be considered. Secondary prevention strategies should be implemented before hospital discharge

Tenecteplase Reperfusion therapy in Acute ischaemic Cerebrovascular Events-II (TRACE II): rationale and design

BACKGROUND AND PURPOSE

Tenecteplase (TNK) is a promising agent for treatment of acute ischaemic stroke (AIS). We hypothesised that recombinant human TNK tissue-type plasminogen activator (rhTNK-tPA) is non-inferior to rt-PA in achieving excellent functional outcome at 90 days, when administered within 4.5 hours of ischaemic stroke onset.

METHODS AND DESIGN

Tenecteplase Reperfusion therapy in Acute ischemic Cerebrovascular Events (TRACE) is a phase III, multicentre, prospective, randomised, open-label, blinded-end point non-inferiority study. Patients eligible for intravenous thrombolysis therapy are randomised to rhTNK-tPA 0.25 mg/kg (single bolus) to a maximum of 25 mg or rt-PA 0.9 mg/kg (10% bolus+90% infusion/1 hour) to a maximum of 90 mg. Medications considered necessary for the patient's health may be given at the discretion of the investigator during 90-day follow-up.

STUDY OUTCOMES

The primary study outcome is excellent functional outcome defined as modified Rankin Scale (mRS) 0-1 at 90 days. Secondary efficacy outcomes include favourable functional outcome defined as mRS ≤2 at 90 days, ordinal distribution of mRS and major neurological improvement on the National Institutes of Health Stroke Scale. Safety outcomes are symptomatic intracranial haemorrhage within 36 hours and death from any cause.

DISCUSSION

There is no completed registration study of TNK in AIS worldwide. TRACE II strives to provide evidence for a new drug application for rhTNK-tPA in AIS within 4.5 hours through a well-designed and rigorously executed randomised trial in China.

TRIAL REGISTRATION NUMBER

NCT04797013.

Tenecteplase Thrombolysis for Acute Ischemic Stroke

Tenecteplase is a fibrinolytic drug with higher fibrin specificity and longer half-life than the standard stroke thrombolytic, alteplase, permitting the convenience of single bolus administration. Tenecteplase, at 0.5 mg/kg, has regulatory approval to treat ST-segment-elevation myocardial infarction, for which it has equivalent 30-day mortality and fewer systemic hemorrhages. Investigated as a thrombolytic for ischemic stroke over the past 15 years, tenecteplase is currently being studied in several phase 3 trials. Based on a systematic literature search, we provide a qualitative synthesis of published stroke clinical trials of tenecteplase that (1) performed randomized comparisons with alteplase, (2) compared different doses of tenecteplase, or (3) provided unique quantitative meta-analyses. Four phase 2 and one phase 3 study performed randomized comparisons with alteplase. These and other phase 2 studies compared different tenecteplase doses and effects on early outcomes of recanalization, reperfusion, and substantial neurological improvement, as well as symptomatic intracranial hemorrhage and 3-month disability on the modified Rankin Scale. Although no single trial prospectively demonstrated superiority or noninferiority of tenecteplase on clinical outcome, meta-analyses of these trials (1585 patients randomized) point to tenecteplase superiority in recanalization of large vessel occlusions and noninferiority in disability-free 3-month outcome, without increases in symptomatic intracranial hemorrhage or mortality. Doses of 0.25 and 0.4 mg/kg have been tested, but no advantage of the higher dose has been suggested by the results. Current clinical practice guidelines for stroke include intravenous tenecteplase at either dose as a second-tier option, with the 0.25 mg/kg dose recommended for large vessel occlusions, based on a phase 2 trial that demonstrated superior recanalization and improved 3-month outcome relative to alteplase. Ongoing randomized phase 3 trials may better define the comparative risks and benefits of tenecteplase and alteplase for stroke thrombolysis and answer questions of tenecteplase efficacy in the >4.5-hour time window, in wake-up stroke, and in combination with endovascular thrombectomy.

The Second Strategic Reperfusion Early After Myocardial Infarction (STREAM-2) study optimizing pharmacoinvasive reperfusion strategy in older ST-elevation myocardial infarction patients

BACKGROUND

The STREAM study demonstrated that a pharmaco-invasive strategy was at least as effective as primary PCI (pPCI) in patients presenting early with ST-elevation myocardial infarction (STEMI). The current trial is a response to the finding that reduced intracranial hemorrhage (ICH) in patients ≥75 years occurred after halving the dose of tenecteplase. Additionally, a subsequent analysis of full dose tenecteplase or alteplase in the Assessment of the Safety and Efficacy of a New Thrombolytic (ASSENT) trials demonstrated a steep increase in bleeding events beginning around the age of 60 years.

METHODS

STREAM-2 will compare the efficacy and safety of a novel pharmaco-invasive strategy as compared to routine pPCI in STEMI patients ≥60 years presenting within 3 hours from symptom onset. In the pharmaco-invasive arm patients will receive half-dose tenecteplase, as soon as possible before transport to a PCI center. In the pPCI arm, patients will be treated according to optimal standard of care defined by local practice. The key criteria for efficacy will be the number of patients achieving ≥50% ST-segment resolution before and after PCI in lead with maximal ST elevation at baseline and the clinical endpoints of death, congestive heart failure, shock or re-infarction, rescue PCI and aborted myocardial infarction, both singularly and as a composite at 30 days. Key safety criteria are total stroke, ICH and major non-intracranial bleeds. Approximately 600 patients will be randomized (400 to pharmaco-invasive treatment and 200 to pPCI). An interim analysis is planned after 300 patients are enrolled to consider adapting the trial to include a larger sample size aimed at undertaking a formal confirmatory trial.

DISCUSSION

The study will provide new insights aimed at establishing an effective and safer pharmaco-invasive treatment for the growing population of older STEMI patients who cannot undergo timely pPCI.

Preintensive care: Thrombolytic (streptokinase or tenecteplase) in ST elevated acute myocardial infarction at peripheral hospital

Background:

Coronary artery disease is a major cause of death in India. Sudden death preceded by chest pain is due to acute myocardial infarction. Villagers are aware and afraid of chest pain. Majority of chest pain victims attend the primary physician in golden hours. Hence, primary doctors can play important role for early thrombolysis and salvage the myocardium from irreversible injury. This study determined year mortality in a patient who received the rapid thrombolysis at primary care hospital (streptokinase or tenecteplase) at rural setting.

Setting:

Peripheral General Hospital Mahad on Mumbai–Goa highway.

Patients and Methods:

Patients with typical chest pain with electrocardiogram showed ST segment elevated myocardial infarction (STEMI) with or without risk factors admitted from 2005 to march 2016 were studied. Details clinically studied: time interval between chest pain to hospital, hospital to needle time, reperfusion and arrhythmias. Time required for regression of elevated ST segment, a response to thrombolytic (streptokinase or tenecteplase) therapy, is studied.

Results:

Total 244 patient reported with chest pain of these 35 cases brought dead with history of chest pain and convulsive moment before they died. Of these, 209 patients had acute STEMI. Of these, 162 received streptokinase (STK) and 47 received tenecteplase (TNP)]. Analysis of STK Vs TNP patients 18 (11.11%) versus 3 (6.38%) (P = 0.361) died during the treatment. Around 17 (18.49%) vs 5 (10.63%) (P = 0.941) did not show signs of reperfusion, respectively. Re infarction occurred during hospitalization 3 (2.5%) versus 3 (6.38%) (P = 0.094) cases. Around 12 (7.40%) versus 0% (P = 0.072) died at the end of 12 months of thrombolytic therapy.

Conclusion:

Thrombolysis of STEMI within golden hours improved the reperfusion. However, 1-year fatality is significance with streptokinase as compared with tenecteplase.

Anticoagulation in the cardiac patient: A concise review

Anticoagulation has multiple roles in the treatment of cardiovascular disease, including in management of acute myocardial infarction, during percutaneous coronary intervention, as stroke prophylaxis in patients with atrial arrhythmias, and in patients with mechanical heart valves. Clinical anticoagulation choices in the aforementioned diseases vary widely, due to conflicting data to support established agents and the rapid evolution of evidence-based practice that parallels more widespread use of novel oral anticoagulants. This review concisely summarizes evidence-based guidelines for anticoagulant use in cardiovascular disease, and highlights new data specific to direct oral anticoagulants.

Anticoagulant Therapy for Acute Coronary Syndromes

Anticoagulation in conjunction with antiplatelet therapy is central to the management of acute coronary syndromes (ACS). When used effectively it is associated with a reduction in recurrent ischaemic events including myocardial infarction and stent thrombosis as well as a reduction in death. Effective ischaemic risk reduction whilst balancing bleeding risk remains a clinical challenge. This article reviews the current available evidence for anticoagulation in ACS and recommendations from the European Society of Cardiology.

Parenteral anticoagulants in heart disease: Current status and perspectives (Section II)

Anticoagulants are a mainstay of cardiovascular therapy, and parenteral anticoagulants have widespread use in cardiology, especially in acute situations. Parenteral anticoagulants include unfractionated heparin, low-molecular-weight heparins, the synthetic pentasaccharides fondaparinux, idraparinux and idrabiotaparinux, and parenteral direct thrombin inhibitors. The several shortcomings of unfractionated heparin and of low-molecular-weight heparins have prompted the development of the other newer agents. Here we review the mechanisms of action, pharmacological properties and side effects of parenteral anticoagulants used in the management of coronary heart disease treated with or without percutaneous coronary interventions, cardioversion for atrial fibrillation, and prosthetic heart valves and valve repair. Using an evidence-based approach, we describe the results of completed clinical trials, highlight ongoing research with currently available agents, and recommend therapeutic options for specific heart diseases.

Association between use of pre-hospital ECG and 30-day mortality: A large cohort study of patients experiencing chest pain

BACKGROUND

In the assessment of patients with chest pain, there is support for the use of pre-hospital ECG in the literature and in the care guidelines. Using propensity score methods, we aim to examine whether the mere acquisition of a pre-hospital ECG among patients with chest pain affects the outcome (30-day mortality).

METHODS

The association between pre-hospital ECG and 30-day mortality was studied in the overall cohort (n=13151), as well as in the one-to-one matched cohort with 2524 patients not examined with pre-hospital ECG and 2524 patients examined with pre-hospital ECG.

RESULTS

In the overall cohort, 21% (n=2809) did not undergo an ECG tracing in the pre-hospital setting. Among those who had pain during transport, 14% (n=1159) did not undergo a pre-hospital ECG while 32% (n=1135) of those who did not have pain underwent an ECG tracing. In the overall cohort, the OR for 30-day mortality in patients who had a pre-hospital ECG, as compared with those who did not, was 0.63 (95% CI 0.05-0.79; p<0.001). In the matched cohort, the OR was 0.65 (95% CI 0.49-0.85; p<0.001). Using the propensity score, in the overall cohort, the corresponding HR was 0.65 (95% CI 0.58-0.74).

CONCLUSION

Using propensity score methods, we provide real-world data demonstrating that the adjusted risk of death was considerably lower among the cases in whoma pre-hospital ECG was used. The PH-ECG is underused among patients with chest discomfort and the mere acquisition of a pre-hospital ECG may reduce mortality.

Antithrombotic treatment tailoring and risk score evaluation in elderly patients diagnosed with an acute coronary syndrome

Age is an important prognostic factor in the outcome of acute coronary syndromes (ACS). A substantial percentage of patients who experience ACS is more than 75 years old, and they represent the fastest-growing segment of the population treated in this setting. These patients present different patterns of responses to pharmacotherapy, namely, a higher ischemic and bleeding risk than do patients under 75 years of age. Our aim was to identify whether the currently available ACS ischemic and bleeding risk scores, which has been validated for the general population, may also apply to the elderly population. The second aim was to determine whether the elderly benefit more from a specific pharmacological regimen, keeping in mind the numerous molecules of antiplatelet and antithrombotic drugs, all validated in the general population. We concluded that the GRACE (Global Registry of Acute Coronary Events) risk score has been extensively validated in the elderly. However, the CRUSADE (Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA Guidelines) bleeding score has a moderate correlation with outcomes in the elderly. Until now, there have not been head-to-head scores that quantify the ischemic versus hemorrhagic risk or scores that use the same end point and timeline (e.g., ischemic death rate versus bleeding death rate at one month). We also recommend that the frailty score be considered or integrated into the current existing scores to better quantify the overall patient risk. With regard to medical treatment, based on the subgroup analysis, we identified the drugs that have the least adverse effects in the elderly while maintaining optimal efficacy.

Controversies in the Management of ST Elevation Myocardial Infarction: Thrombin Inhibition

Anticoagulation is essential in patients with ST elevation myocardial infarction (STEMI) to prevent further thrombosis and to maintain patency of the infarct-related artery after reperfusion. The various anticoagulant medications available for use in patients with STEMI include unfractionated heparin (UFH), low-molecular-weight heparin, fondaparinux, and bivalirudin, a direct thrombin inhibitor. The authors review the current anticoagulation strategies for patients with STEMI undergoing primary percutaneous coronary intervention (PCI), fibrinolysis, or no reperfusion. The authors present the latest evidence and controversies on this topic, with a focus on bivalirudin versus UFH in the setting of primary PCI for STEMI.

The evolution of recombinant thrombolytics: Current status and future directions

Cardiovascular disorders are on the rise worldwide due to alcohol abuse, obesity, hypertension, raised blood lipids, diabetes and age-related risks. The use of classical antiplatelet and anticoagulant therapies combined with surgical intervention helped to clear blood clots during the inceptive years. However, the discovery of streptokinase and urokinase ushered the way of using these enzymes as thrombolytic agents to degrade the fibrin network with an issue of systemic hemorrhage. The development of second generation plasminogen activators like anistreplase and tissue plasminogen activator partially controlled this problem. The third generation molecules, majorly t-PA variants, showed desirable properties of improved stability, safety and efficacy with enhanced fibrin specificity. Plasmin variants are produced as direct fibrinolytic agents as a futuristic approach with targeted delivery of these drugs using liposome technlogy. The novel molecules from microbial, plant and animal origin present the future of direct thrombolytics due to their safety and ease of administration.

Intravenous Enoxaparin Versus Unfractionated Heparin in Elderly Patients Undergoing Primary Percutaneous Coronary Intervention: An Analysis of the Randomized ATOLL Trial

Elderly (≥75 years old) patients with ST-segment elevation myocardial infarction (STEMI) have higher ischemic and bleeding risk compared with those <75 years old. We investigated the efficacy and safety of intravenous (IV) enoxaparin versus IV unfractionated heparin (UFH) in elderly patients undergoing primary percutaneous coronary intervention (PCI) for STEMI. A prespecified analysis of the Acute Myocardial Infarction Treated with Primary Angioplasty and Intravenous Enoxaparin or Unfractionated Heparin to Lower Ischemic and Bleeding Events at Short- and Long-term Follow-up (ATOLL) study was performed examining the 30-day outcomes in the elderly patients. Of the 165 elderly patients in the ATOLL study, 85 patients received IV enoxaparin 0.5 mg/kg and 80 patients received IV UFH. Intravenous enoxaparin did not reduce the primary end point, the main secondary efficacy end point, major bleeding, major or minor bleeding, and all-cause mortality compared with IV UFH. The rate of minor bleeding (5.9% vs 22.8%, P _adjusted = .01) was significantly lower with IV enoxaparin compared with IV UFH. Intravenous enoxaparin appears to be a safe alternative to IV UFH in primary PCI of the elderly patients with STEMI.

Drug Treatment of STEMI in the Elderly: Focus on Fibrinolytic Therapy and Insights from the STREAM Trial

Elderly patients constitute a large and growing proportion of ST-elevation myocardial infarction (STEMI) patients, yet they have been under-represented or even excluded from reperfusion trials. Despite evidence that fibrinolysis improves outcomes irrespective of age, many elderly STEMI patients still remain undertreated or subject to major delays to primary percutaneous coronary intervention (PCI). The fear of an excessive risk of intracranial hemorrhage (ICH) in these patients can lead to avoidance of potentially life-saving reperfusion treatment, despite the fact that current STEMI guidelines do not exclude the elderly from a pharmaco-invasive strategy. Age-specific dose reductions have been succesfully made to antithrombotic drugs such as clopidogrel and enoxaparin as an adjunct to fibrinolysis, but until recently no dose adjustments for elderly patients have been applied to the fibrinolytic agents. In the pharmaco-invasive STREAM trial, halving the bolus of tenecteplase for patients aged >75 years because of an unacceptably high ICH rate in the elderly was associated with a more favorable safety/efficacy profile. Whether a pharmaco-invasive strategy including half-dose tenecteplase, age- and weight-adjusted enoxaparin, and a tailored P2Y12 inhibitor followed by routine angiography represents a safe and efficacious alternative reperfusion therapy for elderly patients remains to be prospectively assessed in a clinical trial in this age group.

A Review of Current Diagnosis, Investigation, and Management of Acute Coronary Syndromes in Elderly Patients

The elderly constitute a sizeable proportion of the acute coronary syndrome (ACS) population, and this population is continually increasing in number. Guideline-directed therapy is frequently underutilized in the elderly due to concerns about patient safety. However, studies suggest that this subgroup could benefit from many of the conventional and newer therapies available. This paper reviews current literature in the context of contemporary American and European guidance.

Stent for Life Initiative: leading example in building STEMI systems of care in emerging countries

This paper describes the opportunities and challenges in building ST-elevation acute myocardial infarction (STEMI) systems of care in Stent for Life affiliated and collaborating so-called emerging countries, namely India, China, South Africa and Mexico, where CAD mortality is increasing and becoming a significant healthcare problem. The Stent for Life model supports the implementation of ESC STEMI Guidelines in Europe and endeavours to impact on morbidity and mortality by improving services and developing regional STEMI systems of care, whereby STEMI patients' timely access to a primary percutaneous coronary intervention (PPCI) is assured. In India, the STEMI India model incorporates a dual approach of combining PPCI with a pharmacoinvasive strategy of reperfusion. The architecture of the system is based on a hub and spoke model with each unit called a STEMI cluster. The project is driven by a private non-profit organisation. In China, the STEMI PCI programme is led by the Chinese College of Cardiovascular Physicians and supported by the national government. Although primary PCI is performed nationwide, a thrombolytic treatment strategy is still the first option in many rural areas because of logistic considerations. Establishing local STEMI transfer networks and then implementing a pharmacoinvasive strategy of reperfusion are being considered and promoted currently. In South Africa, the pharmacoinvasive approach currently dominates as STEMI treatment option in many areas. A pilot study shows that low symptom awareness leads to long patient delays. The education of all role players, from patients to healthcare professionals and including institutions and governmental structures, is needed to achieve prompt diagnosis and treatment. In Mexico, improving the treatment of STEMI requires considering myocardial infarction to be an emergency that must be treated by an entire system and not just by a particular service. Patients need to receive quick treatment from clinical and interventional cardiologists, and the emergency medical system (EMS) must understand the importance of early reperfusion therapy when appropriate. Mexican health authorities have used registries as their main strategy for improving the use of health resources for ACS patients. In general, building regional STEMI systems of care and an EMS system infrastructure are critical success factors in the stepwise development of STEMI systems of care at a national level in emerging countries as they are in Europe. An in-depth understanding of healthcare system-level barriers to timely and appropriate reperfusion therapy facilitates the development of more effective strategies for improving the quality of STEMI care in each region and country.

Unfractionated heparin-clopidogrel combination in ST-elevation myocardial infarction not receiving reperfusion therapy

OBJECTIVE

We sought explore the relative benefits of unfractionated heparin (UFH) compared with enoxaparin, alone or in combination with clopidogrel, in ST-segment elevation myocardial infarction (STEMI) patients not undergoing reperfusion therapy.

METHODS

This is a propensity score study from The International Survey on Acute Coronary Syndromes in Transition Countries (ISACS-TC/NCT01218776) on patients admitted between October 2010-June 2013. There were a total of 1175 STEMI patients who did not receive mechanical or pharmacological reperfusion. Of these, 1063 were eligible for the aim of the study, being treated with UFH (522/1175; 44.4%) or enoxaparin (541/1175; 46%). Clopidogrel in combination with UFH or enoxaparin was given to 751 (63.9%) patients. The primary endpoint was in-hospital mortality. Secondary endpoints were intracranial hemorrhages, and clinically relevant bleedings.

RESULTS

After adjustment for any confounders, UFH was associated with a lower risk of in-hospital mortality in clopidogrel users (multivariate adjusted regression analysis: odds ratio [OR]: 0.62, 95% Confidence Interval [CI] 0.41-0.94) as compared with clopidogrel non-users (OR: 0.94, 95% CI 0.55-1.60). The observed effect was not associated with combined enoxaparin and clopidogrel therapy. Major bleeding events were comparable in the enoxaparin group and UFH group (0.4% and 1.5% respectively, p = 0.06). The risk of major hemorrhage was nearly similar with combined UFH-clopidogrel therapy (1.4%) as compared with UFH alone (1.9%), p = 0.67.

CONCLUSION

UFH - Clopidogrel combination was associated with a large mortality reduction in STEMI patients not undergoing reperfusion therapy and did not significantly increase the risk of major bleeding.

Aspect of thrombolytic therapy: a review

Thrombolytic therapy, also known as clot busting drug, is a breakthrough treatment which has saved untold lives. It has been used in the clinical area to treat venous and arterial thromboembolic complaints which are a foremost cause of death. In 1761, Morgagni lead the way of thrombolytic therapy. Now day's different types of thrombolytic drugs are currently available in market: alteplase, anistreplase, urokinase, streptokinase, tenecteplase, and so forth. Thrombolytic therapy should be given with maintaining proper care in order to minimize the risk of clinically important bleeding as well as enhance the chances of successfully thrombolysis of clot. These cares include preinfusion care, during the infusion care, and postinfusion care. Besides proper knowledge of contraindication, evolutionary factor, and combination of drug is essential for successful thrombolytic therapy. In these review we discussed about these aspect of thrombolytic therapy.

Pre-hospital versus in-hospital thrombolysis for ST-elevation myocardial infarction

BACKGROUND

Early thrombolysis for individuals experiencing a myocardial infarction is associated with better mortality and morbidity outcomes. While traditionally thrombolysis is given in hospital, pre-hospital thrombolysis is proposed as an effective intervention to save time and reduce mortality and morbidity in individuals with ST-elevation myocardial infarction (STEMI). Despite some evidence that pre-hospital thrombolysis may be delivered safely, there is a paucity of controlled trial data to indicate whether the timing of delivery can be effective in reducing key clinical outcomes.

OBJECTIVES

To assess the morbidity and mortality of pre-hospital versus in-hospital thrombolysis for STEMI.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OVID), EMBASE (OVID), two citation indexes on Web of Science (Thomson Reuters) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) for randomised controlled trials and grey literature published up to June 2014. We also searched the reference lists of articles identified, clinical trial registries and unpublished thesis sources. We did not contact pharmaceutical companies for any relevant published or unpublished articles. We applied no language, date or publication restrictions. The Cochrane Heart Group conducted the primary electronic search.

SELECTION CRITERIA

We included randomised controlled trials of pre-hospital versus in-hospital thrombolysis in adults with ST-elevation myocardial infarction diagnosed by a healthcare provider.

DATA COLLECTION AND ANALYSIS

Two authors independently screened eligible studies for inclusion and carried out data extraction and 'Risk of bias' assessments, resolving any disagreement by consulting a third author. We contacted authors of potentially suitable studies if we required missing or additional information. We collected efficacy and adverse effect data from the trials.

MAIN RESULTS

We included three trials involving 538 participants. We found low quality of evidence indicating uncertainty whether pre-hopsital thrombolysis reduces all-cause mortality in individuals with STEMI compared to in-hospital thrombolysis (risk ratio 0.73, 95% confidence interval 0.37 to 1.41). We found high-quality evidence (two trials, 438 participants) that pre-hospital thrombolysis reduced the time to receipt of thrombolytic treatment compared with in-hospital thrombolysis. For adverse events, we found moderate-quality evidence that the occurrence of bleeding events was similar between participants receiving in-hospital or pre-hospital thrombolysis (two trials, 438 participants), and low-quality evidence that the occurrence of ventricular fibrillation (two trials, 178 participants), stroke (one trial, 78 participants) and allergic reactions (one trial, 100 participants) was also similar between participants receiving in-hospital or pre-hospital thrombolysis. We considered the included studies to have an overall unclear/high risk of bias.

AUTHORS' CONCLUSIONS

Pre-hospital thrombolysis reduces time to treatment, based on studies conducted in higher income countries. In settings where it can be safely and correctly administered by trained staff, pre-hospital thrombolysis may be an appropriate intervention. Pre-hospital thrombolysis has the potential to reduce the burden of STEMI in lower- and middle-income countries, especially in individuals who have limited access to in-hospital thrombolysis or percutaneous coronary interventions. We found no randomised controlled trials evaluating the efficacy of pre-hospital thrombolysis for STEMI in lower- and middle-income countries. Large high-quality multicentre randomised controlled trials implemented in resource-constrained countries will provide additional evidence for the efficacy and safety of this intervention. Local policy makers should consider their local health infrastructure and population distribution needs. These considerations should be taken into account when developing clinical guidelines for pre-hospital thrombolysis.

ExTRACT-TIMI 25 trial: clarifying the role of enoxaparin in patients with ST-elevation myocardial infarction receiving fibrinolysis

Pharmacologic reperfusion remains the most common treatment strategy for ST-elevation myocardial infarction (STEMI) worldwide. Unfractionated heparin (UFH) is the established adjunctive antithrombotic agent used with fibrinolytic agents. Low-molecular-weight heparins (LMWHs) are a potential alternative to UFH, but have not been evaluated in large cohorts of patients. The Enoxaparin and Thrombolysis Reperfusion for Acute Myocardial Infarction Treatment (ExTRACT)-Thrombolysis in Myocardial Infarction (TIMI) 25 was a double-blind, double-dummy randomized controlled trial, of 20,479 patients, which demonstrated the superiority of enoxaparin over UFH in reducing death or nonfatal myocardial infarction (MI) at 30 days, with an increase in major bleeding. The composite of death, nonfatal MI and nonfatal intracranial hemorrhage, was reduced with enoxaparin. Elderly patients (> or = 75 years of age) received a novel enoxaparin dosing regimen and when compared with UFH, benefited from a lower relative bleeding risk than younger patients without compromising efficacy in preventing death or MI. Intracranial hemorrhage rates were similar. The net clinical benefit of enoxaparin over UFH was maintained regardless of whether patients were on clopidogrel or not, or whether percutaneous coronary intervention was performed. Enoxaparin is an appropriate choice for adjunctive therapy with fibrinolysis in patients with STEMI.

Enoxaparin in acute coronary syndromes

Enoxaparin is a low-molecular-weight heparin (LMWH) derivative that exerts its anticoagulant activity through antithrombin III, an endogenous inhibitor of factor Xa and thrombin IIa. Unlike its unfractionated heparin (UFH) counterparts, enoxaparin has a greater bioavailability, lower incidence of heparin-induced thrombocytopenia and more stable and predictable anticoagulation, allowing fixed dosing without the need for monitoring. These advantages make it an attractive anticoagulant to be used in acute coronary syndrome management. Indeed, several clinical trials and meta-analyses have consistently demonstrated the efficacy of enoxaparin in reducing cardiovascular events and mortality in this population. Although initial clinical trials with enoxaparin during the early conservative approach suggested superior efficacy without differences in safety compared with UFH, emerging data in the current era of early revascularization approach indicate that superior effects of enoxaparin over heparin in reducing clinical events should be balanced against an increase in major hemorrhagic complications. Enoxaparin is a rational alternative to UFH in patients presenting with either unstable angina/non-ST-elevation myocardial infarction or ST-elevation myocardial infarction, with a clinically modest increase in bleeding complications.

Rationale and methodology for a multicentre randomised trial of fibrinolysis for pulmonary embolism that includes quality of life outcomes

BACKGROUND

Submassive pulmonary embolism (PE) has a low mortality rate but can degrade functional capacity.

OBJECTIVE

The present study aims to provide rationale, methodology, and initial findings of a multicentre, randomised trial of fibrinolysis for PE that used a composite end-point, including quality of life measures.

METHODS

This investigator-initiated study was funded by a contract between a corporate partner and the investigator's hospital (the prime site). The investigator was the Food and Drug Administration (FDA) sponsor. The prime site subcontracted, indemnified, and trained consortia members. Consenting, normotensive patients with PE and right ventricular strain (by echocardiography or biomarkers) received low-molecular-weight heparin and random assignment to a single bolus of tenecteplase or placebo in double-blinded fashion. The outcomes were: (i) in-hospital rate of intubation, vasopressor support, and major haemorrhage, or (ii) at 90 days, death, recurrent PE, or composite that defined poor quality of life (echocardiography, 6 min walk test and surveys). The planned sample size was n = 200.

RESULTS

Eight sites enrolled 87 patients over 5 years. The ratio of patients screened for each enrolled was 7.4 to 1, equating to 11 h screening time per patient enrolled. Primary barrier to enrolment was the cost of screening. Two patients died (2.5%, 95%CI [0-8%]), one developed shock, but 18 (22%, 95%CI: [13-30%]) had a poor quality of life.

CONCLUSIONS

An investigator-initiated, FDA-regulated, multicentre trial of fibrinolysis for submassive PE was conducted, but was limited by screening costs and a low mortality rate. Quality of life measurements might represent a more important patient-centred end-point.

Ticagrelor Versus Clopidogrel in Elderly Patients With Acute Coronary Syndromes

Background—

Elderly patients with acute coronary syndrome are at high risk of recurrent ischemic events and death, and for both antithrombotic therapy and catheter-based complications. This prespecified analysis investigates the effect and treatment-related complications of ticagrelor versus clopidogrel in elderly patients (≥75 years of age) with acute coronary syndrome compared with those <75 years of age.

Methods and Results—

The association between age and the primary composite outcome, as well as major bleeding were evaluated in the PLATelet inhibition and patient Outcomes (PLATO) trial using Cox proportional hazards. Similar models were used to evaluate the interaction of age with treatment effects. Hazard ratios were adjusted for baseline characteristics. The clinical benefit of ticagrelor over clopidogrel was not significantly different between patients aged ≥75 years of age (n=2878) and those <75 years of age (n=15 744) with respect to the composite of cardiovascular death, myocardial infarction, or stroke (interaction P =0.56), myocardial infarction ( P =0.33), cardiovascular death ( P =0.47), definite stent thrombosis ( P =0.81), or all-cause mortality ( P =0.76). No increase in PLATO-defined overall major bleeding with ticagrelor versus clopidogrel was observed in patients aged ≥75 years (hazard ratio, 1.02; 95% confidence interval, 0.82–1.27) or patients aged <75 years (hazard ratio, 1.04; 95% confidence interval, 0.94–1.15). Dyspnea and ventricular pauses were more common during ticagrelor than clopidogrel treatment, with no evidence of an age-by-treatment interaction.

Conclusions—

The significant clinical benefit and overall safety of ticagrelor compared with clopidogrel in acute coronary syndrome patients in the PLATO cohort were not found to depend on age.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00391872.

Cost effectiveness of anticoagulation in acute coronary syndromes

BACKGROUND

The benefit of unfractionated heparin (UFH) added to aspirin in patients with acute coronary syndromes (ACS) was described more than 20 years ago. Ever since, a wide variety of anticoagulant drugs have become available for clinical use, including low-molecular-weight heparins (LMWH), direct thrombin inhibitors and selective factor Xa inhibitors.

OBJECTIVE

The aim of this study was to critically review the available evidence on the cost and incremental cost effectiveness of anticoagulants in patients with ACS.

METHODS

Studies were identified using specialist databases (UK NHS Economic Evaluation Database [NHS EED] and Cost-Effectiveness Analysis [CEA] Registry), PubMed and the reference lists of recovered articles. Only studies based on randomized controlled trials were considered for inclusion. Finally, 22 studies were included in the review.

RESULTS

Enoxaparin is the only LMWH that has been shown to reduce the risk of death or myocardial infarction in patients with non-ST-elevation ACS (NSTE-ACS). In economic studies based on the ESSENCE trial conducted in the late 1990s, enoxaparin was consistently associated with a lower risk of coronary events, a reduction in the number of revascularization procedures and a lower cost per patient than UFH. However, these results refer to patients managed conservatively, with little use of thienopyridines and glycoprotein IIb/IIIa inhibitors, and the results are difficult to extrapolate to moderate-to-high-risk patients managed with the present day early invasive strategy. Available studies of LMWH in ACS with persistent elevation of ST-segment (STE-ACS) are limited to patients treated with thrombolysis. In this scenario, enoxaparin was shown to be a dominant alternative compared with UFH in a study based on the ASSENT-3 study and was considered an economically attractive alternative in three studies based on the ExTRACT-TIMI 25 study. However, these results should be interpreted cautiously due to the heterogeneity of the supportive randomized trials and the possible underestimation of bleeding costs. The effectiveness and safety of bivalirudin, a direct thrombin inhibitor, were evaluated in the ACUITY study (NSTE-ACS patients managed invasively) and the HORIZONS-AMI study (STE acute myocardial infarction patients planned for primary percutaneous coronary intervention). Bivalirudin monotherapy was not inferior to heparin plus a glycoprotein IIb/IIIa inhibitor and reduced the risk of major bleeding. The economic evaluations based on these studies suggest that bivalirudin is an attractive alternative to heparin plus a glycoprotein-IIb/IIIa inhibitor. In the OASIS-5 trial, compared with enoxaparin, fondaparinux reduced the mortality in patients with NSTE-ACS, probably because of a reduced risk of bleeding. In three economic evaluations of fondaparinux versus enoxaparin based on this trial, fondaparinux was the dominant strategy in two of them, and still economically attractive in a third. Taken as a whole, the usefulness of economic studies of anticoagulants in patients with ACS is undermined by the quality of the evidence about their effectiveness and safety; the narrow spectrum of the analysed scenarios; the lack of economic evaluations based on systematic reviews; the limitations of sensitivity analyses reported by the available economic evaluations; and their substantial risk of commercial bias.

CONCLUSIONS

The available studies suggest that enoxaparin is an economically attractive alternative compared with UFH in patients with NSTE-ACS treated conservatively and STE-ACS patients treated with thrombolysis. Bivalirudin in patients with ACS treated invasively is cost effective compared with heparin plus a glycoprotein IIb/IIIa inhibitor. In patients with NSTE-ACS, fondaparinux is cost effective compared with enoxaparin. The usefulness of these results for decision making in contemporary clinical practice is limited due to problems of internal and external validity.

Serine-proteases as plasminogen activators in terms of fibrinolysis

OBJECTIVES

This review should give an overview about the natural human plasminogen activators and their various modified variants as well as similar substances isolated from animals, microorganisms and plants. When a blood clot is formed in a blood vessel, it avoids the oxygen supply of the surrounding tissue. A fast fibrinolytic therapy should redissolve the blood vessel and reduce the degradation of the tissue. All proteases that are part of the human blood coagulation and fibrinolytic system belong to the serine protease family. t-PA (tissue plasminogen activator) and u-PA (urokinase plasminogen activator) are the naturally occurring fibrinolytic agents that are also used in therapy.

KEY FINDINGS

Despite many years of research, t-PA is still the gold standard in fibrinolytic therapy. But it has to be given as an infusion, which needs time. Modified fibrinolytic substances are, were, or perhaps will be in the market. They have different advantages over t-PA, but often the disadvantages predominate.

CONCLUSION

Many substances have been developed but an optimal fibrinolytic agent combined with a simple administration is not in therapeutic use to date.