Optimizing the use of aspirin for cardiovascular prevention

Therapeutic implementation in arterial thrombosis with pulmonary administration of fucoidan microparticles containing acetylsalicylic acid

Several antithrombotic drugs are available to treat cardiovascular diseases due to its high mortality and morbidity worldwide. Despite these, severe adverse effects that can lead to treatment withdrawal have been described, highlighting the importance of new therapies. Thus, this work describes the development of fucoidan microparticles containing acetylsalicylic acid (MP/F4M) for pulmonary delivery and in vitro, ex vivo, and in vivo evaluation. Microparticles were prepared via spray-drying and characterized in vitro (mucoadhesive properties, coagulation time, platelet aggregation, adhesion, and hemolysis) followed by ex vivo platelet aggregation, in vivo arterial thrombosis, and hemorrhagic profile. The formulation physicochemical characterization showed suitable characteristics along with delayed drug release, increased breathable particle fraction, and high washability resistance as well as antiplatelet activity and enhanced platelet adhesion in vitro. In in vivo assays, MP/F4M protected against arterial thrombosis, without changes in the hemorrhagic profile. Finally, no lung changes were observed after prolonged pulmonary administration, whereas isolated ASA led to an inflammatory response. In conclusion, pulmonary administration of fucoidan microparticles with an antiplatelet drug may be an alternative therapy to treat cardiovascular diseases, opening the field for different formulations.

Firefighting Induces Acute Inflammatory Responses that are not Relieved by Aspirin in Older Firefighters

OBJECTIVE

Sudden cardiac events account for 40% to 50% of firefighter line-of-duty deaths. Inflammatory proteins are strong biomarkers of cardiovascular inflammation. The present study investigated the effects of aspirin supplementation on inflammatory biomarkers following firefighting.

METHODS

Using a randomized, placebo-controlled, double-blind crossover design, 24 male firefighters (48.2 ± 5.9 years) were allocated into four conditions: acute (81 mg; single-dose) aspirin and placebo supplementation, and chronic (81 mg; 14 days) aspirin and placebo supplementation. Inflammatory proteins [interleukin (IL)-6, C-reactive protein (CRP), intracellular adhesion molecule (ICAM)-1, P-selectin, matrix metalloproteinase-9 (MMP-9)] and antioxidant potential [total antioxidant capacity (TAC)] were measured pre- and post-structural firefighting drills.

RESULTS

Firefighting activities significantly increased IL-6, MMP-9, and P-Selectin; however, no changes in TAC and ICAM-1 were detected. Neither acute nor chronic aspirin supplementation attenuated this inflammatory response.

CONCLUSION

Firefighting significantly increases inflammatory biomarkers and neither acute nor chronic low-dose aspirin mitigates this response.

Aspirin and omeprazole for secondary prevention of cardiovascular disease in patients at risk for aspirin-associated gastric ulcers

INTRODUCTION

Cardiovascular disease is the most important cause of morbidity and mortality in the world and low-dose aspirin is considered the cornerstone of the cardiovascular disease prevention. However, low-dose aspirin use is associated with gastrointestinal adverse effects in the whole gastrointestinal tract. In this setting, co-therapy with a proton pump inhibitor is the most accepted strategy to reduce aspirin related upper gastrointestinal damage. In addition, some adverse effects have been described with proton pump inhibitors long term use. Areas covered: Low-dose aspirin related beneficial and adverse effects in cardiovascular system and gastrointestinal tract are reviewed. In addition, this manuscript summarizes current data on upper gastrointestinal damage prevention and adverse events with proton pump inhibition. Finally, we discuss the benefit/risk ratio of proton pump inhibitor use in patients at risk of gastrointestinal damage taking low-dose aspirin. Expert commentary: Nowadays, with the current available evidence, the combination of low-dose aspirin with proton pump inhibitor is the most effective therapy for cardiovascular prevention in patients at high gastrointestinal risk. However, further studies are needed to discover new effective strategies with less related adverse events.

Place of non-vitamin K antagonist oral anticoagulants in anticoagulant-antiplatelet combinations in peripheral artery disease

Non-vitamin K antagonist oral anticoagulants are becoming increasingly important in the prophylaxis and treatment of thrombosis in atrial fibrillation and venous thromboembolism. Antiplatelets are widely prescribed in the primary and secondary prevention of cardiac and vascular diseases. There are potentially numerous situations where anticoagulants and antiplatelets may be combined; these combinations have been explored in coronary artery disease, and some have been included in updated recommendations. Is it legitimate to transpose these recommendations to the management of peripheral artery disease? The specific characteristics of the treated vessels, the stents used, the respective frequencies of stent thrombosis and its effect on the target organ are probably different, and explain why opinions differ. However, because of a lack of evidence, empirical behaviours are being established without scientific validation. This review of the literature details the situations in which combinations of an anticoagulant and an antiplatelet have been explored in peripheral artery disease. We discuss the issue of antithrombotic combinations in stable peripheral artery disease and for vascular or endovascular surgery.

Aspirin Use for the Primary Prevention of Cardiovascular Disease in the Elderly

OBJECTIVE

This article aims to use the available evidence assessing aspirin for primary prevention of cardiovascular (CV) events in the elderly to determine its appropriate use.

DATA SOURCES

A literature search of clinical trials and meta-analyses was conducted using MEDLINE and PubMed with the search terms aspirin, bleeding, CV events, elderly, geriatrics, hemorrhage, myocardial infarction (MI), primary prevention, and stroke.

STUDY SELECTION/DATA EXTRACTION

Twelve hundred fourteen (1,214) articles were initially found, and 55 were reviewed. These articles assessed the use of aspirin for primary prevention of CV events. Only trials comparing aspirin with placebo, a non-antiplatelet, or a non-anticoagulant were included in this review. Of the articles reviewed, 10 met the stated criteria.

DATA SYNTHESIS

It is well documented that the risk of CV events increases as patients age. Primary prevention of these events with aspirin may be beneficial in some patients. Currently, a specific recommendation for the use of aspirin for primary prevention in the geriatric population is not available. This paper reviews the available evidence for primary prevention of CV disease. This population is under-represented in the literature, making it challenging to apply the study findings.

CONCLUSION

Aspirin may be considered for the primary prevention of CV events in the elderly population. Because of the lack of data in patients 80 years of age and older, it is difficult to make a decision on the initiation of aspirin therapy in this population. Additional research is necessary to better balance the risk versus benefit of this treatment option.

Aspirin dosing in cardiovascular disease prevention and management: an update

Aspirin has been in use for prevention and management of cardiovascular diseases for several decades. Clinical and epidemiological literature suggests that while net benefits of aspirin in primary prevention of CVDs are less clear, the benefits of aspirin in acute scenarios and secondary prevention settings are well established. However, its optimum dosing requirements have been up for debate especially in various settings of acute coronary syndrome and stable ischemic heart disease. The role of clinician in stratifying individual risk score to achieve net clinical benefit is an important determinant of initiating aspirin therapy. The purpose of this article is to review association of aspirin and CVD in general, and to review its dosing regimens in acute settings as well as primary and secondary prevention as suggested by various established guidelines. We also aim to provide the readers an update on recent changes and current evidence based practice trends.

Drug-Free Platelets Can Act as Seeds for Aggregate Formation During Antiplatelet Therapy

Supplemental Digital Content is available in the text.

Objective—

Reduced antiplatelet drug efficacy occurs in conditions of increased platelet turnover, associated with increased proportions of drug-free, that is, uninhibited, platelets. Here, we detail mechanisms by which drug-free platelets promote platelet aggregation in the face of standard antiplatelet therapy.

Approach and Results—

To model standard antiplatelet therapy, platelets were treated in vitro with aspirin, the P2Y₁₂ receptor blocker prasugrel active metabolite, or aspirin plus prasugrel active metabolite. Different proportions of uninhibited platelets were then introduced. Light transmission aggregometry analysis demonstrated clear positive associations between proportions of drug-free platelets and percentage platelet aggregation in response to a range of platelet agonists. Using differential platelet labeling coupled with advanced flow cytometry and confocal imaging we found aggregates formed in mixtures of aspirin-inhibited platelets together with drug-free platelets were characterized by intermingled platelet populations. This distribution is in accordance with the ability of drug-free platelets to generate thromboxane A₂ and so drive secondary platelet activation. Conversely, aggregates formed in mixtures of prasugrel active metabolite–inhibited or aspirin plus prasugrel active metabolite–inhibited platelets together with drug-free platelets were characterized by distinct cores of drug-free platelets. This distribution is consistent with the ability of drug-free platelets to respond to the secondary activator ADP.

Conclusions—

These experiments are the first to image the interactions of inhibited and uninhibited platelets in the formation of platelet aggregates. They demonstrate that a general population of platelets can contain subpopulations that respond strikingly differently to overall stimulation of the population and so act as the seed for platelet aggregation.

Potential role of aspirin in the prevention of aneurysmal subarachnoid hemorrhage

BACKGROUND

Inflammation is a key element behind the pathophysiology of cerebral aneurysm formation and rupture. Aspirin is a potent inhibitor of cyclooxygenase-2 (COX), which plays a critical role in the expression of immune modulators known to contribute to cerebral aneurysm formation and rupture. Currently, there are no pharmacological therapies for patients with cerebral aneurysms. Both endovascular and microsurgical interventions may be associated with significant morbidity and mortality. Potentially, a medical alternative that prevents aneurysm progression and rupture may be a beneficial therapy for a significant number of patients.

SUMMARY

In animal models, treatment with aspirin and genetic inactivation of COX-2 decreases aneurysm formation and rupture. Selective inhibition of COX-1 did not decrease aneurysm rupture, suggesting that selection inhibition of COX-2 may be critical in thwarting aneurysm progression. Walls of ruptured human intracranial aneurysms have higher levels of COX-2 and microsomal prostaglandin E2 synthase 1 (mPGES-1), both of which are known to be inhibited by aspirin. In a pilot study, patients undergoing microsurgical clipping had attenuated expression of COX-2, mPGES-1, and macrophages in aneurysm walls after 3 months of aspirin therapy versus those that did not receive aspirin. Additionally, in patients undergoing endovascular therapy, local circulating expression of chemokines and COX-2 were increased in blood samples taken from within aneurysm domes as compared to peripheral blood sample controls. Treatment with aspirin also resulted in decreased expression of COX-2 within leukocytes within aneurysms as compared to peripheral blood samples. Novel molecular imaging with ferumoxytol-enhanced MRI may help in the identification of patients at increased risk for aneurysm rupture and assessment of a response to aspirin therapy. Key Messages: Aspirin has been found to be a safe in patients harboring cerebral aneurysms and clinical studies provide evidence that it may decrease the overall rate of rupture. Furthermore, aspirin is an accessible and inexpensive medicine for patients who may not have access to endovascular or microsurgical treatment or for patients who are deemed low risk of aneurysm rupture, high risk for intervention, or both. Future clinical trials are indicated to determine the overall effect of aspirin on aneurysm progression and rupture. This review provides an update on the potential mechanisms and benefits of aspirin in the treatment of cerebral aneurysms.

Effects of anti-aggregant, anti-inflammatory and anti-coagulant drug consumption on the preparation and therapeutic potential of plasma rich in growth factors (PRGF)

The prevalence and incidence of trauma-related injuries, coronary heart disease and other chronic diseases increase dramatically with age. This population sector is therefore a regular consumer of different types of drugs that may affect platelet aggregation and the coagulation cascade. We have evaluated whether the consumption of acetylsalicylic acid, acenocoumarol, glucosamine sulfate and chondroitin sulfate, and therefore their presence in blood, could interfere with the preparation and biological outcomes of plasma rich in growth factors (PRGF). Clotting time, clot retraction and platelet activation of PRGF was evaluated. PRGF growth factor content and the release of different biomolecules by tendon fibroblasts were also quantified, as well as cell proliferation and cell migration. The preparation and biological potential of PRGF is not affected by the intake of the evaluated drugs, and solely its angiogenic potential and its capacity to induce HA and fibronectin synthesis, is reduced in patients taking anti-coagulants.