Glycoprotein IIb/IIIa inhibitors in the treatment of thromboembolic events related to endovascular treatment of cerebral aneurysms-systematic review and meta-analysis.

BACKGROUND AND AIMS: Thromboembolism complication is considered the most common complication associated with the treatment of endovascular. This systematic review and meta-analysis aimed to assess the studies investigating the effect of glycoprotein IIb/IIIa inhibitor agents on thromboembolic complications during endovascular aneurysm coiling. MATERIALS AND METHODS: This systematic review investigated the outcome of the use of three glycoprotein IIb/IIIa inhibitor agents (ie abciximab, tirofiban, and eptifibatide) on the thromboembolic complications during endovascular aneurysm coiling. The electronic databases of PubMed, Web of Science, Scopus, and Medline were searched up to 25 June 2021, using the keywords "Abciximab," "Tirofiban," and "Eptifibatide" incombination with "Thromboembolism Complication," "Aneurysms," and "Endovascular Aneurysm Coiling." RESULTS: A total of 21 articles were found to be eligible and included in this review. The rates of complete and partial recanalization were estimated to be 56% and 92% in patients who underwent abciximab and tirofiban therapy, respectively. Rupture aneurysms were found in the majority of patients. In general, the mortality rate of the patients treated for thromboembolic complications during endovascular treatment of cerebral aneurysms with glycoprotein IIb/IIIa inhibitors was found to be 4.8% (CI 95%:0.027-0.067; p < .005). The average remission rate in studies investigating thromboembolism was 91% (CI 95%:0.88-0.95, I2 : 65.65/p < .001). CONCLUSION: Based on the obtained results, a higher mean rate of complete recanalization by eptifibatide was found in studies in which abciximab or tirofiban were used, compared to other mentioned agents. Moreover, the amount of hemorrhage was reported to be less after using tirofiban rather than abciximab.

Eptifibatide, an Older Therapeutic Peptide with New Indications: From Clinical Pharmacology to Everyday Clinical Practice.

Therapeutic peptides are oligomers or short polymers of amino acids used for various medical purposes. Peptide-based treatments have evolved considerably due to new technologies, stimulating new research interests. They have been shown to be beneficial in a variety of therapeutic applications, notably in the treatment of cardiovascular disorders such as acute coronary syndrome (ACS). ACS is characterized by coronary artery wall damage and consequent formation of an intraluminal thrombus obstructing one or more coronary arteries, leading to unstable angina, non-ST elevated myocardial infarction, and ST-elevated myocardial infarction. One of the promising peptide drugs in the treatment of these pathologies is eptifibatide, a synthetic heptapeptide derived from rattlesnake venom. Eptifibatide is a glycoprotein IIb/IIIa inhibitor that blocks different pathways in platelet activation and aggregation. In this narrative review, we summarized the current evidence on the mechanism of action, clinical pharmacology, and applications of eptifibatide in cardiology. Additionally, we illustrated its possible broader usage with new indications, including ischemic stroke, carotid stenting, intracranial aneurysm stenting, and septic shock. Further research is, however, required to fully evaluate the role of eptifibatide in these pathologies, independently and in comparison to other medications.

A Double-Blinded Randomized Controlled Trial Comparing Eptifibatide Bolus Only Versus Bolus Plus Infusion In Patients Undergoing Primary Percutaneous Coronary Intervention For ST-Elevation Myocardial Infarction.

BACKGROUNDS: The use of eptifibatide combined with heparin during percutaneous coronary intervention (PCI) in patients presenting with ST-elevation myocardial infarction (STEMI) is recommended to be followed by continuous infusion. Recently, there are some suggestions that using bolus only may be sufficient and cost-effective but randomized trials are lacking. AIMS: The goal of this study was to evaluate these two approaches in a double-blinded randomized control trial. METHODS: The primary PCI patients who received bolus eptifibatide were randomized to 75 mg IV eptifibatide infusion or placebo blindly. The patients were followed up for the primary outcome of vascular or bleeding complications and secondary outcome of ischemic complications. RESULTS: 330 patients (165 from each group) completed the study. The mean age was 57.67 ± 11.53 years and 77.3 % were male. Major bleeding was seen in 1 patient in each group. Hematoma occurred in 8.5 %. The relative risk of hematoma and ecchymosis in bolus plus infusion group to bolus only group were 0.988 (95 % CI: 0.486-2.006) and 1.032 (95 % CI: 0.729-1.459). Multivariate analysis confirmed no significant differences in the bleeding event. Furthermore, there was no significant difference in in-hospital death or any ischemic events. (Cath lab death: 1.4 % in bolus only vs zero % in the control group, p = 0.217, stent thrombosis was seen in one patient in each group). CONCLUSION: There were no differences in the risk of access site ecchymosis, hematoma or major bleeding. Ischemic events and stent thrombosis rates were also similar. Our study suggests that using eptifibatide bolus only during PCI of patients with STEMI is safe and can be cost-saving.

Studying the efficacy of antiplatelet drugs on atherosclerosis by optofluidic imaging on a chip.

Vascular stenosis caused by atherosclerosis instigates activation and aggregation of platelets, eventually resulting in thrombus formation. Although antiplatelet drugs are commonly used to inhibit platelet activation and aggregation, they unfortunately cannot prevent recurrent thrombotic events in patients with atherosclerosis. This is partially due to the limited understanding of the efficacy of antiplatelet drugs in the complex hemodynamic environment of vascular stenosis. Conventional methods for evaluating the efficacy of antiplatelet drugs under stenosis either fail to simulate the hemodynamic environment of vascular stenosis characterized by high shear stress and recirculatory flow or lack spatial resolution in their analytical techniques to statistically identify and characterize platelet aggregates. Here we propose and experimentally demonstrate a method comprising an in vitro 3D stenosis microfluidic chip and an optical time-stretch quantitative phase imaging system for studying the efficacy of antiplatelet drugs under stenosis. Our method simulates the atherogenic flow environment of vascular stenosis while enabling high-resolution and statistical analysis of platelet aggregates. Using our method, we distinguished the efficacy of three antiplatelet drugs, acetylsalicylic acid (ASA), cangrelor, and eptifibatide, for inhibiting platelet aggregation induced by stenosis. Specifically, ASA failed to inhibit stenosis-induced platelet aggregation, while eptifibatide and cangrelor showed high and moderate efficacy, respectively. Furthermore, we demonstrated that the drugs tested also differed in their efficacy for inhibiting platelet aggregation synergistically induced by stenosis and agonists (e.g., adenosine diphosphate, and collagen). Taken together, our method is an effective tool for investigating the efficacy of antiplatelet drugs under vascular stenosis, which could assist the development of optimal pharmacologic strategies for patients with atherosclerosis.

Anti-Platelet Peptides Targeting αIIbß3 Outside-In Signaling Pathway.

Platelets and their progenitors express high levels of integrin αIIbß3, which plays a key role in platelet functions, hemostasis, and arterial thrombosis. Because of their quick and high efficacy, the three anti-αIIbß3 drugs, abciximab, eptifibatide, and tirofiban, are regarded as potent anti-thrombotics and clinically approved by US Food and Drug Administration. However, because they interfere with the inside-out signaling of αIIbß3, which is required for stable platelet adhesion and aggregation, the application of abciximab, eptifibatide, and tirofiban is restricted to patients undergoing percutaneous coronary intervention. On the other hand, the outside-in signaling of αIIbß3 in platelets appears to be responsible for thrombus stabilization, and selective interference with the propagation of outside-in signals might signify a new therapeutic strategy to preferentially inhibit platelet-rich arterial thrombosis with less bleeding issues caused by way of compromised major hemostasis. The purpose of this review is to describe the bidirectional signal transduction of integrin αIIbß3 in platelets with a focus on outside-in signaling, more efficient and safer anti-αIIbß3 peptides, and the potential drug targets for future anti-platelet research.

Single-antiplatelet regimen in ruptured cerebral blood blister and dissecting aneurysms treated with flow-diverter stent reconstruction.

BACKGROUND: Flow diversion treatment of ruptured cerebral aneurysms remains challenging due to the need for double-antiplatelet therapy. We report our experience with flow-diverter stent (FDS) reconstruction with single-antiplatelet therapy of ruptured cerebral blood blister and dissecting aneurysms. METHODS: In this case series we performed a retrospective analysis of all patients with ruptured cerebral aneurysms who were treated with a phosphoryl-bonded FDS between 2019 and 2022 in a single center. Periprocedurally, all patients received weight-adapted eptifibatide IV and heparin IV. After 6-24 hours, eptifibatide was switched to oral prasugrel as monotherapy. We analyzed the rate of bleeding complications, thromboembolic events, occlusion rate and clinical outcome. RESULTS: Nine patients with subarachnoid hemorrhage were treated, eight within 24 hours of symptom onset. Seven patients were treated with one FDS and two patients received two FDS in a telescopic fashion. Two aneurysms were additionally coil embolized. Fatal re-rupture occurred in one case; eight patients survived and had no adverse events associated with the FDS. Six patients showed complete occlusion of the aneurysm after 3 months (n=2) and 1 year (n=4), respectively. Two patients showed subtotal occlusion of the aneurysm at the last follow-up after 3 months and 6 months, respectively. Favorable clinical outcome was achieved in five patients. CONCLUSIONS: Peri-interventional single-antiplatelet therapy with eptifibatide followed by prasugrel was sufficient to prevent thromboembolic events and reduce re-bleeding using an anti-thrombogenic FDS. FDS with single-antiplatelet therapy might be a viable option for ruptured blood blister and dissecting cerebral aneurysms.

The Pharmacological Effects of Silver Nanoparticles Functionalized with Eptifibatide on Platelets and Endothelial Cells.

Purpose: In the search for new drug delivery platforms for cardiovascular diseases and coating of medical devices, we synthesized eptifibatide-functionalized silver nanoparticles (AgNPs-EPI) and examined the pharmacological activity of AgNPs-EPI on platelets and endothelial cells in vitro and ex vivo. Methods: Spherical AgNPs linked to eptifibatide were synthesized and characterized. Cytotoxicity was measured in microvascular endothelial cells (HMEC-1), platelets and red blood cells. Platelet mitochondrial respiration was measured using the Oxygraph-2k, a high-resolution modular respirometry system. The effect of AgNPs-EPI on the aggregation of washed platelets was measured by light aggregometry and the ex vivo occlusion time was determined using a reference laboratory method. The surface amount of platelet receptors such as P-selectin and GPIIb/IIIa was measured. The influence of AgNPS-EPI on blood coagulation science was assessed. Finally, the effect of AgNPs-EPI on endothelial cells was measured by the levels of 6-keto-PGF1alpha, tPa, cGMP and vWF. Results: We describe the synthesis of AgNPs using eptifibatide as the stabilizing ligand. The molecules of this drug are directly bonded to the surface of the nanoparticles. The synthesized AgNPs-EPI did not affect the viability of platelets, endothelial cells and erythrocytes. Preincubation of platelets with AgNPs-EPI protected by mitochondrial oxidative phosphorylation capacity. AgNPs-EPI inhibited aggregation-induced P-selectin expression and GPIIb/IIIa conformational changes in platelets. AgNPs-EPI caused prolongation of the occlusion time in the presence of collagen/ADP and collagen/adrenaline. AgNPs-EPI regulated levels of 6-keto-PGF1alpha, tPa, vWf and cGMP produced in thrombin stimulated HMEC-1 cells. Conclusion: AgNPs-EPI show anti-aggregatory activity at concentrations lower than those required by the free drug acting via regulation of platelet aggregation, blood coagulation, and endothelial cell activity. Our results provide proof-of-principle evidence that AgNPs may be used as an effective delivery platform for antiplatelet drugs.

Unraveling the role of the homoarginine residue in antiplatelet drug eptifibatide in binding to the αIIbß3 integrin receptor.

Eptifibatide is an αIIbß3 inhibitor that is currently used in the clinic. More than 10 scientific communications indicate that eptifibatide has a Lys-Gly-Asp or Arg-Gly-Asp sequence, while it actually has a hArg-Gly-Asp sequence. We aimed to unravel the importance of the homoarginine residue in eptifibatide in platelet activation and aggregation. Arg- and Lys-eptifibatide were synthesized by solid-phase peptide synthesis and measured in light transmission aggregometry, flow cytometry and whole blood thrombus formation under flow. Interactions of eptifibatide and its variants with αIIbß3 integrin were studied using molecular dynamics simulations. Eptifibatide showed inhibition of collagen- and ADP-induced platelet aggregation, while Arg- and Lys-eptifibatide did not. Multiparameter assessment of thrombus formation showed suppressed platelet aggregate and fibrin formation upon eptifibatide treatment, in contrast to the other variants. Molecular dynamics simulations revealed that the hArg residue in eptifibatide is crucial to its activity, since the substitution of the hArg to Arg or Lys resulted in the inability to form double H-bonds with Asp224 in the αIIb chain of the αIIbß3 receptor. The hArg is pivotal for the interaction of eptifibatide for the αIIbß3 receptor and efficient inhibition of platelet aggregation.

Inhibition of Src but not Syk causes weak reversal of GPVI-mediated platelet aggregation measured by light transmission aggregometry.

Src tyrosine kinases and spleen tyrosine kinase (Syk) have recently been shown to contribute to sustained platelet aggregation on collagen under arterial shear. In the present study, we have investigated whether Src and Syk are required for aggregation under minimal shear following activation of glycoprotein VI (GPVI) and have extended this to C-type lectin-like receptor-2 (CLEC-2) which signals through the same pathway. Aggregation was induced by the GPVI ligand collagen-related peptide (CRP) and the CLEC-2 ligand rhodocytin and monitored by light transmission aggregometry (LTA). Aggregation and tyrosine phosphorylation by both receptors were sustained for up to 50 min. The addition of inhibitors of Src, Syk or Bruton's tyrosine kinase (Btk) at 150 sec, by which time aggregation was maximal, induced rapid loss of tyrosine phosphorylation of their downstream proteins, but only Src kinase inhibition caused a weak (~10%) reversal in light transmission. A similar effect was observed when the inhibitors were combined with apyrase and indomethacin or glycoprotein IIb-IIIa (GPIIb-IIIa) antagonist, eptifibatide. On the other hand, activation of GPIIb-IIIa by GPVI in a diluted platelet suspension, as measured by binding of fluorescein isothiocyanate-labeled antibody specific for the activated GPIIb-IIIa (FITC-PAC1), was reversed on the addition of Src and Syk inhibitors showing that integrin activation is rapidly reversible in the absence of outside-in signals. The results demonstrate that Src but not Syk and Btk contribute to sustained aggregation as monitored by LTA, possibly as a result of inhibition of outside-in signaling from GPIIb-IIIa to the cytoskeleton through a Syk-independent pathway. This is in contrast to the role of Syk in supporting sustained aggregation on collagen under arterial shear.

Safety and Efficacy of Periprocedural Bridging With Cangrelor Versus Eptifibatide.

ABSTRACT: Patients with percutaneous coronary interventions undergoing procedures often require interruptions in their dual antiplatelet therapy. Periprocedural bridging is considered for patients at high thrombotic risk using intravenous cangrelor, a reversible P2Y12 inhibitor with a short half-life, or eptifibatide, a glycoprotein IIb/IIIa inhibitor, with a slightly longer half-life but less costly alternative. This study aims to assess the safety and efficacy of cangrelor compared with eptifibatide when used in a periprocedural setting. The primary outcome of this retrospective cohort study was the incidence of bleeding events defined by the global use of strategies to open occluded coronary arteries criteria, and the secondary outcomes include the transfusion requirements, inpatient major cardiac adverse events, and cost savings per patient. A total of 75 patients were included who were bridged to procedures (cangrelor, n = 50; eptifibatide, n = 25). There were no significant differences in overall bleeding events defined by global use of strategies to open occluded coronary arteries criteria: mild bleeding [8% (n= 4) vs. 8% (n= 2); P = 0.68], moderate bleeding [28% (n = 14) vs. 48% (n = 12); P = 0.07), and severe bleeding [8% (n = 4) vs. 8% (n = 2); P = 0.25] between cangrelor and eptifibatide. The composite inpatient major cardiac adverse events were also similar between cangrelor and eptifibatide [10% (n = 10) vs. 8% (n = 8); P = 0.78]. The average cost savings per each cangrelor patient on the equivalent duration of eptifibatide was calculated out to be $5824 per patient. Cangrelor and eptifibatide were similar in terms of safety and efficacy when used as a bridge in patients with recent coronary stents, but considerable cost savings could be made if cangrelor was substituted for by eptifibatide in select patients. Further studies are needed to determine its applicability specifically in patients at high thrombotic and hemorrhagic risk.

Efficacy and safety of a bridging strategy that uses intravenous platelet glycoprotein receptor inhibitors for patients undergoing surgery after coronary stent implantation: a meta-analysis.

BACKGROUND: Current guidelines indicate we can consider a bridging strategy that uses intravenous, reversible glycoprotein inhibitors for patients that required surgery following recent stent implantation. However, no strong clinical evidence exists that demonstrates the efficacy and safety of this treatment. Therefore, in this study, the efficacy and safety of a bridging strategy that uses intravenous platelet glycoprotein receptor inhibitors will be evaluated. METHODS: A meta-analysis was performed on preoperative bridging studies in patients undergoing coronary stent surgery. The primary outcome was the success rate of no major adverse cardiovascular events (MACE). The secondary outcomes were the success rate of no reoperations to stop bleeding. RESULTS: A total of 10 studies that included 382 patients were used in this meta-analysis. For the primary endpoint, the success rate was 97.7% (95% CI 94.4-98.0%) for glycoprotein IIb/IIIa inhibitors, 98.8% (95% CI 96.0-100%) for tirofiban (6 studies) and 95.8% (95% CI 90.4-99.4%) for eptifibatide (4 studies). For secondary endpoints, the success rate was 98.0% (95% CI 94.8-99.9%) for glycoprotein IIb/IIIa inhibitors, 99.7% (95% CI 97.1-100%) for tirofiban (5 studies), and 95.3% (95% CI 88.5-99.4%) for eptifibatide (4 studies). CONCLUSION: The results of this study showed that the use of intravenous platelet glycoprotein IIb/IIIa inhibitors as a bridging strategy might be safe and effective for patients undergoing coronary stent implantation that require surgery soon after.

Bridging Antiplatelet Therapy After Percutaneous Coronary Intervention: JACC Review Topic of the Week.

Patients undergoing early surgery after coronary stent implantation are at increased risk for mortality from ischemic and hemorrhagic complications. The optimal antiplatelet strategy in patients who cannot discontinue dual antiplatelet therapy (DAPT) before surgery is unclear. Current guidelines, based on surgical and clinical characteristics, provide risk stratification for bridging therapy with intravenous antiplatelet agents, but management is guided primarily by expert opinion. This review summarizes perioperative risk factors to consider before discontinuing DAPT and reviews the data for intravenous bridging therapies. Published reports have included bridging options such as small molecule glycoprotein IIb/IIIa inhibitors (eptifibatide or tirofiban) and cangrelor, an intravenous P2Y12 inhibitor. However, optimal management of these complex patients remains unclear in the absence of randomized controlled data, without which an argument can be made both for and against the use of perioperative intravenous bridging therapy after discontinuing oral P2Y12 inhibitors. Multidisciplinary risk assessment remains a critical component of perioperative care.

Successful Use of Glycoprotein IIb/IIIa Inhibitor Involving Severely Ill COVID-19 Patient.

This case report describes a successful outcome involving a patient with severe COVID-19 viral pneumonia utilizing a novel therapeutic approach with the glycoprotein IIb/IIIa inhibitor, eptifibatide.

Blood transfusion and ischaemic outcomes according to anemia and bleeding in patients with non-ST-segment elevation acute coronary syndromes: Insights from the TAO randomized clinical trial.

BACKGROUND: The benefits and risks of blood transfusion in patients with acute myocardial infarction who are anemic or who experience bleeding are debated. We sought to study the association between blood transfusion and ischemic outcomes according to haemoglobin nadir and bleeding status in patients with NST-elevation myocardial infarction (NSTEMI). METHODS: The TAO trial randomized patients with NSTEMI and coronary angiogram scheduled within 72h to heparin plus eptifibatide versus otamixaban. After exclusion of patients who underwent coronary artery bypass surgery, patients were categorized according to transfusion status considering transfusion as a time-varying covariate. The primary ischemic outcome was the composite of all-cause death or MI within 180 days of randomization. Subgroup analyses were performed according to pre-transfusion hemoglobin nadir and bleeding status. RESULTS: 12,547 patients were enrolled. Among these, blood transfusion was used in 489 (3.9%) patients. Patients who received transfusion had a higher rate of death or MI (29.9% vs. 8.1%, p<0.01). This excess risk persisted after adjustment on GRACE score and nadir of hemoglobin (HR 3.36 95%CI 2.63-4.29 p<0.01). Subgroup analyses showed that blood transfusion was associated with a higher risk in patients without overt bleeding (adjusted HR 6.25 vs. 2.85; p-interaction 0.001) as well as in those with hemoglobin nadir > 9.0 g/dl (HR 4.01; p-interaction<0.0001). CONCLUSION: In patients with NSTEMI, blood transfusion was associated with an overall increased risk of ischaemic events. However, this was mainly driven by patients without overt bleeding and those hemoglobin nadir > 9.0g/dl. This suggests possible harm of transfusion in those groups.

Effects of Crushed Ticagrelor Versus Eptifibatide Bolus Plus Clopidogrel in Troponin-Negative Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention: A Randomized Clinical Trial.

Background After a loading dose of ticagrelor, the rate of high on-treatment platelet reactivity remains elevated, which increases periprocedural myocardial infarction and injury. This indicates that faster platelet inhibition with crushed ticagrelor (CTIC) or eptifibatide is needed to reduce high on-treatment platelet reactivity. The efficacy of CTIC versus eptifibatide bolus plus clopidogrel is unknown. Methods and Results A total of 100 P2Y12 naïve, troponin-negative patients with acute coronary syndrome were randomized to CTIC (180 mg) versus eptifibatide bolus (180 µg/kg×2 intravenous boluses) plus clopidogrel (600 mg) at the time of percutaneous coronary intervention. High on-treatment platelet reactivity was markedly higher with CTIC versus eptifibatide bolus plus clopidogrel (42% versus 0%; P<0.001) at 30 minutes and persisted up to 2 hours (12% versus 0%; P=0.01, respectively). Platelet aggregation by adenosine diphosphate dropped faster from baseline with eptifibatide bolus plus clopidogrel versus CTIC (0.5 versus 2 hours, respectively) and was higher with CTIC versus eptifibatide bolus plus clopidogrel at 0.5, 2, and 4 hours after loading dose (53±12% versus 1.3±2%; 35±11% versus 0.34±1.0%; and 23±9% versus 3.5±2%, respectively; P<0.001). Eptifibatide bolus plus clopidogrel, but not CTIC, significantly inhibited platelet aggregation induced by thrombin-receptor activating peptide. Periprocedural myocardial infarction and injury was higher with CTIC versus eptifibatide bolus plus clopidogrel (48% versus 28%, respectively; P=0.035). Post-percutaneous coronary intervention hemoglobin levels were not different between groups. Conclusions Eptifibatide bolus plus clopidogrel led to faster and more potent platelet inhibition than CTIC and reduced periprocedural myocardial infarction and injury in troponin-negative acute coronary syndrome patients undergoing percutaneous coronary intervention, with no significant hemoglobin drop after percutaneous coronary intervention. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02925923.

Acute Carotid Stent Thrombosis in an Ultrarapid Clopidogrel Metabolizer: Case Report and Literature Review.

INTRODUCTION: Carotid angioplasty and stenting (CAS) represents an effective procedure for treating carotid artery disease. The acute in-stent thrombosis is an extremely rare complication of CAS especially when it occurs postprocedurally during the first 24 hours. Improper antiplatelet therapy or poor response to antiplatelet medications is known to be associated with a higher risk of in-stent thrombosis during early postprocedural period following a successful intervention. MATERIAL AND METHODS: A patient who experienced acute carotid in-stent thrombosis in early postprocedural period is described. He had been taking dual antiplatelet therapy for 2 weeks before undergoing a successful CAS. Moreover, pharmacogenetics studies showed the patient to be a clopidogrel ultrarapid metabolizer, which theoretically confers hyperresponsivity to medication. Alongside the report itself, a brief literature review of relevant sources pertinent to the case has been conducted. RESULTS: According to the available literature, this is the first case report describing an ultrarapid clopidogrel metabolizer who underwent an uneventful CAS but experienced acute carotid in-stent thrombosis in early postprocedural period. A rescue procedure included an endovascular intervention consisting of thrombectomy and local alteplase application, followed by postprocedural administration of intravenous eptifibatide. At discharge, patient's dual antiplatelet therapy included ticagrelor instead of clopidogrel. CONCLUSION: Acute carotid in-stent thrombosis is a highly unexpected complication of CAS and can occur despite ultrarapid clopidogrel metabolism trait.

Platelet integrin αIIbß3: signal transduction, regulation, and its therapeutic targeting.

Integrins are a family of transmembrane glycoprotein signaling receptors that can transmit bioinformation bidirectionally across the plasma membrane. Integrin αIIbß3 is expressed at a high level in platelets and their progenitors, where it plays a central role in platelet functions, hemostasis, and arterial thrombosis. Integrin αIIbß3 also participates in cancer progression, such as tumor cell proliferation and metastasis. In resting platelets, integrin αIIbß3 adopts an inactive conformation. Upon agonist stimulation, the transduction of inside-out signals leads integrin αIIbß3 to switch from a low- to high-affinity state for fibrinogen and other ligands. Ligand binding causes integrin clustering and subsequently promotes outside-in signaling, which initiates and amplifies a range of cellular events to drive essential platelet functions such as spreading, aggregation, clot retraction, and thrombus consolidation. Regulation of the bidirectional signaling of integrin αIIbß3 requires the involvement of numerous interacting proteins, which associate with the cytoplasmic tails of αIIbß3 in particular. Integrin αIIbß3 and its signaling pathways are considered promising targets for antithrombotic therapy. This review describes the bidirectional signal transduction of integrin αIIbß3 in platelets, as well as the proteins responsible for its regulation and therapeutic agents that target integrin αIIbß3 and its signaling pathways.

Novel Antiplatelet Perioperative Bridging Protocol for Lung Lobectomy: A Case Report.

INTRODUCTION: Some patients with cardiac stents will need thoracic surgery during the dual antiplatelet therapy (DAPT) period. When surgery cannot be safely delayed to allow 1 year of uninterrupted DAPT, appropriate perioperative management of anticoagulation is critical. CASE PRESENTATION: A patient treated with new drug-eluting stents and DAPT was concomitantly diagnosed with lung cancer and required a lobectomy. We describe the novel addition of ticagrelor (a short-acting oral antiplatelet agent) to eptifibatide (a short-acting intravenous antiplatelet agent) to bridge DAPT for surgery. DISCUSSION: This ticagrelor-eptifibatide perioperative bridge resulted in decreased preoperative hospitalization compared with eptifibatide alone. There were no associated perioperative cardiac or bleeding complications.

Intravenous Antiplatelet Therapy Bridging in Patients Undergoing Cardiac or Non-Cardiac Surgery Following Percutaneous Coronary Intervention.

BACKGROUND: The effect of perioperative bridging therapy on risks of ischemic cardiac events and major bleeding complications in patients on dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI) remains undefined. METHODS: We report on 60 consecutive patients between 2010 and 2017 who required cardiac (CS; n = 15) or non-cardiac (NCS; n = 45) surgeries following PCI at our institution. Short-acting intravenous (IV) antiplatelet (APT) bridging with eptifibatide, tirofiban and cangrelor were instituted after DAPT interruption. RESULTS: All patients were men with multiple atherosclerosis risk factors. An acute coronary syndrome indication (56.7%) was the most common PCI indication in the CS and NCS groups. Drug-eluting stents were used in 93.33% and 95.56% of the above groups, respectively. The median duration from PCI to CS and NCS were 11.17 and 18.25 months, respectively and 38.33% of all surgeries were performed within 6 months of the index PCI. Most patients were on background aspirin (83.33%) and clopidogrel (81.67%) and median duration of DAPT interruption was 7 days. Median duration of perioperative IV APT bridging was 3 days for CS and 5 days for NCS groups. In the CS group, two patients (13.33%) had non-fata myocardial infarction (MI), and four (26.67%) had clinically significant bleeding. No patients had perioperative stent thrombosis. In the NCS group, one patient (2.22%) had stent thrombosis; four (6.67%) had myocardial infarction, and five (11.11%) clinically significant bleeding. CONCLUSIONS: Despite using IV APT as bridging therapy during perioperative DAPT interruption in post-PCI patients, postoperative cardiac events and bleeding complications can still occur.

Prolonged use of eptifibatide as a bridge to maintain drug-eluting stent patency in a patient receiving extracorporeal membrane oxygenation.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been used as a bridge to cardiac recovery in patients following a major cardiac event. There is a lack of literature surrounding prolonged use of eptifibatide and optimal dosing during ECMO. This case report describes our experience with extended durations and standard dosing of eptifibatide in the setting of ECMO. CASE: A 40-year-old male with a history of Marfan's syndrome, aortic root and ascending aortic aneurysm status post a modified Bentall with a St. Jude mechanical aortic valve conduit and hemi-Cabrol with a Dacron graft to the left main coronary artery presented with exertional chest pain and was found to have an anastomotic narrowing to the left main which occluded while awaiting surgical revision. A rescue percutaneous coronary intervention at the anastomotic site was performed. Due to hemodynamic instability, he was placed on femoral VA-ECMO. The patient was started on anticoagulation for the ECMO circuit and eptifibatide to maintain stent patency. The patient experienced several bleeding episodes for which he received supportive care, endoscopic intervention and left gastric artery embolization. Eptifibatide was maintained at standard dosing and the heparin infusion was withheld. A coronary angiogram revealed no thrombus within the Cabrol graft a patent stent previously placed at the site of the distal graft-coronary anastomosis. The patient was decannulated from ECMO and underwent coronary artery bypass grafting and division of the hemi-Cabrol graft. CONCLUSION: While eptifibatide was effective in maintaining stent patency, our patient experienced several bleeding episodes during ECMO. Thus, the risks and benefits of concurrent antiplatelet and anticoagulant therapy must be appropriately weighed in this patient population. Additionally, as the need for dual antiplatelet therapy due to coronary stent implantation is increasing, further studies are needed to validate optimal dosing of eptifibatide in patients at a high risk of bleeding during ECMO.