51
|
Efeovbokhan N, Khouzam RN, Al-Fakhouri A, Salama L. An objective comparison between bivalirudin and heparin during peripheral vascular interventions. Future Cardiol 2014; 10:717-24. [DOI: 10.2217/fca.14.50] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
ABSTRACT Patients undergoing percutaneous peripheral interventions are at increased risk for thrombotic complications hence the routine use of periprocedural anticoagulants. There is currently no American College of Cardiology/American Heart Association guidelines for periprocedural anticoagulants use in percutaneous peripheral interventions. Historically, unfractionated heparin has been the most common periprocedural anticoagulant used during percutaneous peripheral interventions. There may be a role for more predictable periprocedural anticoagulants in percutaneous peripheral interventions as has been demonstrated in percutaneous coronary interventions. Our review focuses on the evidence supporting the use of bivalirudin in percutaneous peripheral interventions.
Collapse
Affiliation(s)
- Nephertiti Efeovbokhan
- Department of Medicine, Division of Cardiovascular Diseases, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Rami N Khouzam
- Department of Medicine, Division of Cardiovascular Diseases, University of Tennessee Health Science Center, Memphis, TN, USA
| | | | | |
Collapse
|
52
|
Paksefat S, Rahimi S. Root canal treatment of a two-rooted C-shaped maxillary first molar: a case report. IRANIAN ENDODONTIC JOURNAL 2014; 81:E9-14. [PMID: 25386214 DOI: 10.1002/ccd.24279] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/16/2011] [Accepted: 11/25/2011] [Indexed: 01/14/2023]
Abstract
The most difficult maxillary teeth for endodontic treatment are the maxillary first molars (MFM) due to their complex root canal anatomy. The presence of two roots and C-shaped canals in MFMs has been reported in rare cases. The present case reports root canal treatment of MFM with two roots, where the palatal and buccal roots were joined together in a C-shaped configuration.
Collapse
Affiliation(s)
- Sara Paksefat
- Department of Endodontics, Dental and Periodontal Research Center, Tabriz Dental School, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Rahimi
- Department of Endodontics, Dental and Periodontal Research Center, Tabriz Dental School, Tabriz University of Medical Sciences, Tabriz, Iran
| |
Collapse
|
53
|
Antithrombin concentrate in pediatric patients requiring unfractionated heparin anticoagulation: a retrospective cohort study. Pediatr Crit Care Med 2014; 15:e340-6. [PMID: 24901804 DOI: 10.1097/pcc.0000000000000174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To describe antithrombin levels, altered unfractionated heparin effect (anti-factor Xa activity and activated partial thromboplastin time), and adverse effects post administration of a single high dose of antithrombin concentrate. DESIGN Retrospective review. PATIENTS Infants and children with antithrombin levels less than 50% and a subtherapeutic unfractionated heparin effect. SETTING Quaternary care children's hospital with a dedicated anticoagulation program. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS A single high dose of antithrombin concentrate was administered. Antithrombin level, anti-factor Xa, and activated partial thromboplastin times were measured post antithrombin concentrate infusion and daily until stable. One hundred twenty-one patients received 246 doses of antithrombin. Patients were described using two cohorts based on the ability to obtain exact heparin doses. Cohort 1 included all patients between January 2004 and May 2008 when complete heparin dosing was unavailable. Cohort 2 included patients from May 2008 to May 2011 when heparin dose was available. Median age and weight were 3.7 months and 4.1 kg. Mean antithrombin concentrate dose was 222 IU/kg. Mean antithrombin level increased from 0.39 to 1.20 U/mL following antithrombin concentrate administration. In cohort 2, unfractionated heparin doses to achieve a target anti-factor Xa activity pre-post antithrombin concentrate were 28 and 19 U/kg/hr, respectively, for children 12 months old or younger and 25 and 19 U/kg/hr, respectively, for children older than 12 months. There were no hemorrhagic, thrombotic, or allergic events within 1 week of antithrombin concentrate administration. CONCLUSIONS This is the largest study of antithrombin concentrate evaluation in children. Administration of antithrombin concentrate increases anti-factor Xa activity with lower administered unfractionated heparin doses.
Collapse
|
54
|
Administration of Antithrombin Concentrate in Infants and Children on Extracorporeal Life Support Improves Anticoagulation Efficacy. ASAIO J 2014; 60:559-63. [DOI: 10.1097/mat.0000000000000099] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
55
|
Breik O, Cheng A, Sambrook PJ, Goss AN. Protocol in managing oral surgical patients taking dabigatran. Aust Dent J 2014; 59:296-301; quiz 401. [DOI: 10.1111/adj.12199] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2013] [Indexed: 11/27/2022]
Affiliation(s)
- O Breik
- Oral and Maxillofacial Surgery Unit; Royal Adelaide Hospital; Adelaide South Australia
| | - A Cheng
- Oral and Maxillofacial Surgery Unit; Royal Adelaide Hospital; Adelaide South Australia
| | - PJ Sambrook
- Oral and Maxillofacial Surgery Unit; Royal Adelaide Hospital; Adelaide South Australia
| | - AN Goss
- The University of Adelaide and Emeritus Consultant; Oral and Maxillofacial Surgery Unit; Royal Adelaide Hospital; Adelaide South Australia
| |
Collapse
|
56
|
Major TC, Brisbois EJ, Jones AM, Zanetti ME, Annich GM, Bartlett RH, Handa H. The effect of a polyurethane coating incorporating both a thrombin inhibitor and nitric oxide on hemocompatibility in extracorporeal circulation. Biomaterials 2014; 35:7271-85. [PMID: 24927680 DOI: 10.1016/j.biomaterials.2014.05.036] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 05/15/2014] [Indexed: 01/23/2023]
Abstract
Nitric oxide (NO) releasing (NORel) materials have been extensively investigated to create localized increases in NO concentration by the proton driven diazeniumdiolate-containing polymer coatings and demonstrated to improve extracorporeal circulation (ECC) hemocompatibility. In this work, the NORel polymeric coating composed of a diazeniumdiolated dibutylhexanediamine (DBHD-N2O2)-containing hydrophobic Elast-eon™ (E2As) polyurethane was combined with a direct thrombin inhibitor, argatroban (AG), and evaluated in a 4 h rabbit thrombogenicity model without systemic anticoagulation. In addition, the immobilizing of argatroban to E2As polymer was achieved by either a polyethylene glycol-containing (PEGDI) or hexane methylene (HMDI) diisocyanate linker. The combined polymer film was coated on the inner walls of ECC circuits to yield significantly reduced ECC thrombus formation compared to argatroban alone ECC control after 4 h blood exposure (0.6 ± 0.1 AG/HMDI/NORel vs 1.7 ± 0.2 cm(2) AG/HMDI control). Platelet count (2.8 ± 0.3 AG/HMDI/NORel vs 1.9 ± 0.1 × 10(8)/ml AG/HMDI control) and plasma fibrinogen levels were preserved after 4 h blood exposure with both the NORel/argatroban combination and the AG/HMDI control group compared to baseline. Platelet function as measured by aggregometry remained near normal in both the AG/HMDI/NORel (63 ± 5%) and AG/HMDI control (58 ± 7%) groups after 3 h compared to baseline (77 ± 1%). Platelet P-selectin mean fluorescence intensity (MFI) as measured by flow cytometry also remained near baseline levels after 4 h on ECC to ex vivo collagen stimulation (16 ± 3 AG/HMDI/NORel vs 11 ± 2 MFI baseline). These results suggest that the combined AG/HMDI/NORel polymer coating preserves platelets in blood exposure to ECCs to a better degree than AG/PEGDI/NORel, NORel alone or AG alone. These combined antithrombin, NO-mediated antiplatelet effects were shown to improve thromboresistance of the AG/HMDI/NORel polymer-coated ECCs and move potential nonthrombogenic polymers closer to mimicking vascular endothelium.
Collapse
Affiliation(s)
- Terry C Major
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI, USA.
| | | | - Anna M Jones
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Margaux E Zanetti
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Gail M Annich
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Robert H Bartlett
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Hitesh Handa
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI, USA.
| |
Collapse
|
57
|
Abstract
Low-molecular-weight heparins have several important advantages over unfractionated heparin (UFH). Due to a longer plasma half life together with high bioavailability and a linear dose-response relationship, the drugs can be safely and effectively administered in the hospital or ambulatory settings without the need to monitor the anticoagulant effect. Enoxaparin (Lovenox), Aventis Pharma) is a low-molecular-weight heparin which has been studied in a variety of clinical situations. In general surgery the efficacy of enoxaparin to prevent venous thromboembolism is similar to UFH but the tolerability is better. In patients undergoing cancer, orthopedic or vascular surgery the efficacy of enoxaparin is significantly higher with similar rates of bleeding complications. The database for enoxaparin in nonsurgical patients is smaller compared with surgical groups. There is evidence that the efficacy of enoxaparin may be superior to UFH in patients with severe cardiac disease. Efficacy and safety of UFH and enoxaparin are similar for the treatment of deep vein thrombosis. However, enoxaparin can be safely administered by the patients at home which is not possible with UFH. In patients with acute coronary syndromes, enoxaparin has been shown to reduce the rate of deaths and serious cardiac events in comparison with UFH. Furthermore, exonaparin treatment has been shown to be cost-effective, and therefore is the therapy of choice in this setting. In addition, enoxaparin has been shown to be a safe and effective alternative to the combination of UFH and phenprocoumone therapy in patients undergoing electrical cardioversion for atrial fibrillation.
Collapse
Affiliation(s)
- Thomas Hofmann
- Universitätsklinikum Hamburg-Eppendorf, Herzzentrum, Medizinische Klinik III, Martinistr. 52, 20246 Hamburg, Germany.
| |
Collapse
|
58
|
Mehta RS. Novel oral anticoagulants. Part II: direct thrombin inhibitors. Expert Rev Hematol 2014; 3:351-61. [DOI: 10.1586/ehm.10.12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
59
|
Holinstat M, Colowick NE, Hudson WJ, Blakemore D, Chen Q, Hamm HE, Cleator JH. Dichotomous effects of exposure to bivalirudin in patients undergoing percutaneous coronary intervention on protease-activated receptor-mediated platelet activation. J Thromb Thrombolysis 2013; 35:209-22. [PMID: 23054462 DOI: 10.1007/s11239-012-0812-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Bivalirudin is a direct thrombin inhibitor that is increasingly used in percutaneous coronary intervention (PCI) and has been previously shown to lack inherent platelet activation. Thrombin works through activation of protease activated receptor-1 (PAR1) and PAR4 on human platelets to initiate signaling cascades leading to platelet aggregation. Despite the increasing usage of bivalirudin, the effects on platelet function have not been well defined. Bivalirudin exposure during PCI was therefore assessed for its potential short-term effects on washed platelet function through PAR1 and PAR4. Bivalirudin significantly inhibited low-dose thrombin-mediated platelet aggregation, dense granule secretion, integrin αIIbβ3 activation and Rap1 activation and high dose thrombin-mediated dense granule secretion and Rap1 activation. Exposure to bivalirudin did not alter PAR1 or 4 agonist peptide (PAR1-AP or PAR4-AP) induced aggregation, dense granule secretion, integrin glycoprotein IIbIIIa activation or Rap1 activation. However, exposure to bivalirudin significantly potentiated surface expression of P-selectin following stimulation with high dose thrombin and PAR1-AP, and both low and high dose PAR4-AP. Hence, our data are the first to show that exposure to bivalirudin increased P-selectin expression with certain conditions demonstrating that bivalirudin can increase inherent platelet activity.
Collapse
Affiliation(s)
- Michael Holinstat
- Department of Medicine, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA, USA
| | | | | | | | | | | | | |
Collapse
|
60
|
Abstract
Since percutaneous transluminal coronary angioplasty was first described and the breakthrough studies of the role of stents were reported, the evolution in anticoagulation and antiplatelet therapy used during percutaneous coronary intervention (PCI) has reduced periprocedural ischemic events and stent thrombosis. Although greater combinations and doses of anticoagulation with antiplatelets seem to provide the best protection against thrombogenic and embolic events, there is a significant trade-off with a higher risk of major and minor bleeding episodes. This review article expands on each of the commonly used antiplatelet and anticoagulants used at time of PCI, focusing on drug monitoring and reversal.
Collapse
Affiliation(s)
- Gregory W Yost
- Department of Cardiology, Geisinger Medical Center, 100 North Academy Avenue, Danville, PA 17822, USA.
| | - Steven R Steinhubl
- Department of Cardiology, Geisinger Medical Center, 100 North Academy Avenue, Danville, PA 17822, USA
| |
Collapse
|
61
|
Song Y, Song JW, Shim JK, Kwak YL. Optimal anticoagulation during off pump coronary artery bypass in patients recently exposed to clopidogrel. Yonsei Med J 2013; 54:1119-26. [PMID: 23918560 PMCID: PMC3743205 DOI: 10.3349/ymj.2013.54.5.1119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE The aim of this study was to find an optimal range of activated clotting time (ACT) during off-pump coronary artery bypass surgery (OPCAB) yielding ischemic protection without the risk of hemorrhagic complications in patients with recent exposure to dual antiplatelet therapy. MATERIALS AND METHODS Three hundred and five patients who received aspirin and clopidogrel within 7 days of isolated multi-vessel OPCAB were retrospectively studied. Combined hemorrhagic and ischemic outcome was defined as the occurrence of 1 of the following: significant perioperative bleeding (>30% of estimated blood volume), transfusion of packed red blood cell (pRBC) ≥ 2 U, or myocardial infarction (MI). This was compared in relation to the tertile distribution of the time-weighted average ACT-212-291 sec (first tertile), 292-334 sec (second tertile), 335-485 sec (third tertile). RESULTS The amount of perioperative blood loss was 937 ± 313 mL, 1014 ± 340 mL, and 1076 ± 383 mL, respectively (p=0.022). Significantly more patients in the third tertile developed MI (4%, 4%, and 12%, respectively, p=0.034). The incidence of significant perioperative blood loss and transfusion of pRBC ≥ 2 U were lower in the first tertile than those of other tertiles without statistical significance. In the multivariate analysis, the first tertile was associated with a 52% risk reduction of combined hemorrhagic and ischemic outcomes (95% confidence interval: 0.25-0.92, p= 0.027). CONCLUSION A lower degree of anticoagulation with a reduced initial heparin loading dose should be carefully considered for patients undergoing OPCAB who have recently been exposed to clopidogrel.
Collapse
Affiliation(s)
- Young Song
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
- Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Wook Song
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
- Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jae Kwang Shim
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
- Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Young Lan Kwak
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
- Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
| |
Collapse
|
62
|
Ten Y, Devlin G. Bivalirudin in acute coronary syndromes and percutaneous coronary intervention: should we use it? Heart Lung Circ 2013; 22:793-800. [PMID: 23916503 DOI: 10.1016/j.hlc.2013.05.636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/08/2013] [Accepted: 05/11/2013] [Indexed: 10/26/2022]
Abstract
Major bleeding remains a major risk factor for percutaneous coronary intervention of acute coronary syndromes and is associated with higher morbidity, mortality, prolonged hospital stay and costs. With the recognition that bleeding is an important factor in patient outcomes, the prevention of bleeding has become as important a goal as the prevention of ischaemia. The direct thrombin inhibitor bivalirudin has been shown to reduce ischaemia and importantly, is associated with less bleeding. In this article we review the evidence base that supports the use of bivalirudin across all spectrums of coronary syndromes and percutaneous coronary intervention. An algorithm for the use of bivalirudin in high risk subgroups and coronary syndromes is suggested.
Collapse
Affiliation(s)
- Yuli Ten
- Hollywood Hospital, Cardiology, Nedlands, WA 6009, Australia.
| | | |
Collapse
|
63
|
Ellis CR, Kaiser DW. The clinical efficacy of dabigatran etexilate for preventing stroke in atrial fibrillation patients. Vasc Health Risk Manag 2013; 9:341-52. [PMID: 23874100 PMCID: PMC3711881 DOI: 10.2147/vhrm.s28271] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The use of novel oral anticoagulants (NOACs) for stroke and systemic embolism prevention in the setting of specifically non valvular atrial fibrillation has provided clinicians with a realistic treatment alternative to the traditional dose-adjusted, warfarin-based anticoagulation that is targeted to a therapeutic international normalized ratio range of 2.0–3.0. We discuss the use of dabigatran in the setting of mechanical heart valves, atrial fibrillation or left atrial catheter ablation procedures, reversal of the drug in the setting of adverse bleeding events, and background on the molecular biology and development of this novel treatment for stroke reduction.
Collapse
|
64
|
Platelets are dominant contributors to hypercoagulability after injury. J Trauma Acute Care Surg 2013; 74:756-62; discussion 762-5. [PMID: 23425732 DOI: 10.1097/ta.0b013e3182826d7e] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Venous thromboembolic (VTE) disease has a high incidence following trauma, but debate remains regarding optimal prophylaxis. Thrombelastography (TEG) has been suggested to be optimal in guiding prophylaxis. Thus, we designed a phase II randomized controlled trial to test the hypothesis that TEG-guided prophylaxis with escalating low-molecular weight heparin (LMWH), followed by antiplatelet therapy would reduce VTE incidence. METHODS Surgical intensive care unit trauma patients (n = 50) were randomized to receive 5,000 IU of LMWH daily (control) or to TEG-guided prophylaxis, up to 5,000 IU twice daily with the addition of aspirin, and were followed up for 5 days. In vitro studies were also conducted in which apheresis platelets were added to blood from healthy volunteers (n = 10). RESULTS Control (n = 25) and TEG-guided prophylaxis (n = 25) groups were similar in age, body mass index, Injury Severity Score, and male sex. Fibrinogen levels and platelet counts did not differ, and increased LMWH did not affect clot strength between the control and study groups. The correlation of clot strength (G value) with fibrinogen was stronger on Days 1 and 2 but was superseded by platelet count on Days 3, 4, and 5. There was also a trend in increased platelet contribution to clot strength in patients receiving increased LMWH. In vitro studies demonstrated apheresis platelets significantly increased clot strength (7.19 ± 0.35 to 10.34 ± 0.29), as well as thrombus generation (713.86 ± 12.19 to 814.42 ± 7.97) and fibrin production (274.03 ± 15.82 to 427.95 ± 16.58). CONCLUSION Increased LMWH seemed to increase platelet contribution to clot strength early in the study but failed to affect the overall rise clot strength. Over time, platelet count had the strongest correlation with clot strength, and in vitro studies demonstrated that increased platelet counts increase fibrin production and thrombus generation. In sum, these data suggest an important role for antiplatelet therapy in VTE prophylaxis following trauma, particularly after 48 hours. LEVEL OF EVIDENCE Therapeutic study, level III.
Collapse
|
65
|
De Servi S, Mariani G, Mariani M, D’Urbano M. The bivalirudin paradox. J Cardiovasc Med (Hagerstown) 2013; 14:334-41. [DOI: 10.2459/jcm.0b013e32835f1915] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
66
|
Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE, Chavey WE, Fesmire FM, Hochman JS, Levin TN, Lincoff AM, Peterson ED, Theroux P, Wenger NK, Wright RS, Jneid H, Ettinger SM, Ganiats TG, Philippides GJ, Jacobs AK, Halperin JL, Albert NM, Creager MA, DeMets D, Guyton RA, Kushner FG, Ohman EM, Stevenson W, Yancy CW. 2012 ACCF/AHA focused update incorporated into the ACCF/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2013; 61:e179-347. [PMID: 23639841 DOI: 10.1016/j.jacc.2013.01.014] [Citation(s) in RCA: 373] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
67
|
McMahon GS, Jones CI, Hayes PD, Naylor AR, Goodall AH. Transient heparin-induced platelet activation linked to generation of platelet 12-lipoxygenase. Findings from a randomised controlled trial. Thromb Haemost 2013; 109:1099-107. [PMID: 23494053 DOI: 10.1160/th12-11-0793] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 01/31/2013] [Indexed: 11/05/2022]
Abstract
Previously we demonstrated that heparin administration during carotid endarterectomy (CEA) caused a marked, but transient increase in platelet aggregation to arachidonic acid (AA) and adenosine diphosphate (ADP), despite effective platelet cyclo-oxygenase-1 (COX-1) inhibition with aspirin. Here we investigated the metabolism of AA via platelet 12-lipoxygenase (12-LOX) as a possible mediator of the observed transient aspirin resistance, and compared the effects of unfractionated (UFH) and low-molecular-weight (LMWH) heparin. A total of 43 aspirinated patients undergoing CEA were randomised in the trial to 5,000 IU UFH (n=22) or 2,500 IU LMWH (dalteparin, n=21). Platelet aggregation to AA (4x10⁻³) and ADP (3x10⁻⁶) was determined, and the products of the COX-1 and 12-LOX pathways; thromboxane B₂ (TXB₂) and 12-hydroxyeicosatretraenoic acid (12-HETE) were measured in plasma, and in material released from aggregating platelets.Aggregation to AA increased significantly (~10-fold) following heparinisation (p<0.0001), irrespective of heparin type (p=0.33). Significant, but smaller (~2-fold) increases in aggregation to ADP were also seen, which were significantly lower in the platelets of patients randomised to LMWH (p<0.0001). Plasma levels of TxB2 did not rise following heparinisation (p=0.93), but 12-HETE increased significantly in the patients' plasma, and released from platelets stimulated in vitro withADP, with both heparin types (p<0.0001). The magnitude of aggregation to ADP correlated with 12-HETE generation (p=0.03). Heparin administration during CEA generates AA that is metabolised to 12-HETE via the 12-LOX pathway, possibly explaining the phenomenon of transient heparin-induced platelet activation. LMWH has less effect on aggregation and 12-HETE generation than UFH when the platelets are stimulated with ADP.
Collapse
Affiliation(s)
- Greg S McMahon
- Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield Hospital, Leicester, LE3 9QP, UK
| | | | | | | | | |
Collapse
|
68
|
De Servi S, Mariani G, Mariani M, D'Urbano M. How to reduce mortality in ST-elevation myocardial infarction patients treated with primary percutaneous coronary interventions: cut the bleeding. Curr Med Res Opin 2013; 29:189-94. [PMID: 23350949 DOI: 10.1185/03007995.2013.770389] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND In-hospital mortality for ST-elevation myocardial infarction (STEMI) has declined thanks to a greater use of primary percutaneous coronary interventions (PCI) associated with more effective antiplatelet and anticoagulant drugs. In this regard, bivalirudin has been shown to decrease total and cardiac mortality as compared to unfractionated heparin (UFH). OBJECTIVE The primary purpose of this analysis is to evaluate the hypothesis that the reduction of in-hospital bleeding is the most plausible explanation for the improved survival of STEMI patients treated with bivalirudin during primary PCI. The secondary objective is to reconsider the prognostic significance of the radial access alone or in association with bivalirudin on the basis of the published data. METHODS We have done a comprehensive evaluation of the main and related publications of the HORIZONS-AMI trial in addition to an extensive research by Medline of randomized trials evaluating the prognostic impact of radial access as compared with the femoral one in primary PCI. RESULTS In the HORIZONS-AMI trial bivalirudin resulted in significantly lower rates of the 30 day primary endpoint (defined as major adverse ischemic outcomes plus major bleeding) over UFH plus GPI, largely due to the significantly lower rate of the protocol-defined major bleeding. All-cause and cardiac mortality were also reduced in the bivalirudin arm at 3 year follow-up. Recent studies have also shown that the use of the radial instead of the femoral approach for primary PCI is associated with reduced bleeding as well as reduced mortality. CONCLUSIONS Our research suggests that decreasing bleeding by either a pharmacologic strategy (use of bivalirudin) or a technical approach (the transradial access) improves survival in STEMI patients undergoing primary PCI. The validity of this hypothesis should be confirmed by specific randomized trials.
Collapse
Affiliation(s)
- Stefano De Servi
- Department of Cardiovascular Diseases, Ospedale Civile di Legnano, Milan, Italy.
| | | | | | | |
Collapse
|
69
|
Point-of-care assessment of hypothermia and protamine-induced platelet dysfunction with multiple electrode aggregometry (Multiplate®) in patients undergoing cardiopulmonary bypass. Anesth Analg 2013; 116:533-40. [PMID: 23400974 DOI: 10.1213/ane.0b013e31827cee88] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Coagulopathy is common after cardiopulmonary bypass (CPB), and platelet dysfunction is frequently considered to be a major contributor to excessive bleeding. Exposure to hypothermia may exacerbate the platelet function defect. We assessed platelet function during and after deep hypothermia with multiple electrode aggregometry (Multiplate(®); Verum Diagnostica GmbH, Munich, Germany). METHODS Twenty adult patients undergoing pulmonary endarterectomy for chronic pulmonary hypertension were cooled on CPB to 20°C and deep hypothermic arrest was used to facilitate surgery. We analyzed platelet aggregation in whole blood samples at 12 measuring points during and after the procedure. Platelet aggregation was stimulated via the thrombin receptor (TRAPtest) at the patient's actual body temperature (AUC-CT) and after rewarming the samples to 37°C (AUC-37). In addition, we tested samples at 2 time points after 2 minutes of in vitro incubation with 20 μg protamine (0.067 μg/μL). Results are expressed as area under the aggregation curve (AUC). RESULTS Cooling resulted in a marked decrease of platelet aggregation to a minimum AUC-CT of 20.5 (95% confidence interval [CI] 8.9-32.1) at 20°C body temperature. AUC-CT was significantly different from baseline (92.8, 95% CI 82.5-103.1) for temperatures of ≤28°C (P < 0.001), whereas the change in AUC-37 only became significant at the lowest body temperature (59.4, 95% CI 41.3-77.4). After rewarming to 36°C, AUC-CT and AUC-37 had recovered to 67.6 (95% CI 53.9-81.3) and 71.7 (95% CI 52.5-90.8), respectively. The mean AUC-CT was significantly lower than the mean AUC-37 from cooling at 28°C to warming at 24°C inclusive, and the relationship with temperature during cooling was significantly different between AUC-CT and AUC-37 (regression coefficients 4.7 [95% CI 4.2-5.2] vs 1.3 [95% CI 0.7-1.9]; P < 0.0001). After administration of protamine, mean aggregation decreased significantly for both measurements by 38.2 (95% CI -27.9 to -48.5; P < 0.001) and 44.5 (95% CI -58.5 to -30.5; P < 0.001), respectively. Similarly, adding protamine in vitro resulted in a decrease of mean aggregation by 35.1 (95% CI -71.0 to 0.8; P = 0.055) when measured after administration of heparin, and 56.5 (95% CI -94.5 to -18.5; P = 0.005) at the end of CPB. CONCLUSION Platelet aggregation, assessed by multiple electrode aggregometry (Multiplate), was severely affected during deep, whole-body hypothermia. This effect was partially reversible after rewarming, and was distinct from a general decline of platelet aggregation during CPB. Protamine also caused a significant decrease in platelet aggregation in vivo and in vitro.
Collapse
|
70
|
Breik O, Tadros R, Devitt P. Thrombin inhibitors: surgical considerations and pharmacology. ANZ J Surg 2013; 83:215-21. [PMID: 23384088 DOI: 10.1111/ans.12078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2012] [Indexed: 11/28/2022]
Abstract
The new thrombin inhibitors have provided an exciting opportunity for effective thromboprophylaxis without some of the disadvantages of the current anticoagulants. These drugs are orally administered, have predictable pharmacokinetics and dose-response, do not require monitoring and have an acceptable safety profile when used appropriately. However, inappropriate prescribing of these drugs may lead to catastrophic consequences. Clinicians need to be aware of some of the drawbacks associated with the use of dabigatran and, in particular, its reduced clearance in the setting of renal failure and the lack of an effective reversing agent when bleeding does occur. In this review, the evidence for efficacy and safety of dabigatran is discussed. We also aim to provide practical clinical advice on the pre- and post-operative management of the elective and emergency surgical patient on dabigatran and provide guidelines for the management of acute haemorrhage in the context of dabigatran therapy.
Collapse
Affiliation(s)
- Omar Breik
- Department of Surgery, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | | | | |
Collapse
|
71
|
Antithrombotic and anticoagulant effects of direct factor Xa inhibitor darexaban in rat and rabbit models of venous thrombosis. Eur J Pharmacol 2013. [DOI: 10.1016/j.ejphar.2012.11.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
72
|
Koscielny J, Rutkauskaite E. Präinterventionelle Änderung der Gerinnungsmedikation. VISZERALMEDIZIN 2013. [DOI: 10.1159/000355383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
73
|
Hoshi RA, Van Lith R, Jen MC, Allen JB, Lapidos KA, Ameer G. The blood and vascular cell compatibility of heparin-modified ePTFE vascular grafts. Biomaterials 2012; 34:30-41. [PMID: 23069711 DOI: 10.1016/j.biomaterials.2012.09.046] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 09/21/2012] [Indexed: 12/21/2022]
Abstract
Prosthetic vascular grafts do not mimic the antithrombogenic properties of native blood vessels and therefore have higher rates of complications that involve thrombosis and restenosis. We developed an approach for grafting bioactive heparin, a potent anticoagulant glycosaminoglycan, to the lumen of ePTFE vascular grafts to improve their interactions with blood and vascular cells. Heparin was bound to aminated poly(1,8-octanediol-co-citrate) (POC) via its carboxyl functional groups onto POC-modified ePTFE grafts. The bioactivity and stability of the POC-immobilized heparin (POC-Heparin) were characterized via platelet adhesion and clotting assays. The effects of POC-Heparin on the adhesion, viability and phenotype of primary endothelial cells (EC), blood outgrowth endothelial cells (BOECs) obtained from endothelial progenitor cells (EPCs) isolated from human peripheral blood, and smooth muscle cells were also investigated. POC-Heparin grafts maintained bioactivity under physiologically relevant conditions in vitro for at least one month. Specifically, POC-Heparin-coated ePTFE grafts significantly reduced platelet adhesion and inhibited whole blood clotting kinetics. POC-Heparin supported EC and BOEC adhesion, viability, proliferation, NO production, and expression of endothelial cell-specific markers von Willebrand factor (vWF) and vascular endothelial-cadherin (VE-cadherin). Smooth muscle cells cultured on POC-Heparin showed increased expression of α-actin and decreased cell proliferation. This approach can be easily adapted to modify other blood contacting devices such as stents where antithrombogenicity and improved endothelialization are desirable properties.
Collapse
Affiliation(s)
- Ryan A Hoshi
- Biomedical Engineering Department, Northwestern University, Evanston, IL 60208, USA
| | | | | | | | | | | |
Collapse
|
74
|
Merriweather N, Sulzbach-Hoke LM. Managing Risk of Complications at Femoral Vascular Access Sites in Percutaneous Coronary Intervention. Crit Care Nurse 2012; 32:16-29; quiz first page after 29. [DOI: 10.4037/ccn2012123] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Percutaneous coronary intervention for acute coronary syndrome or non–ST-elevation myocardial infarction requires the use of potent oral and intravenous anti-platelet and antithrombin medications. Although these potent antithrombotic agents and regimens may increase the effectiveness of percutaneous coronary intervention, they are also generally associated with an increased risk of vascular access complications such as hematoma, retroperitoneal hematoma, pseudoaneurysm, arterial occlusion, and arteriovenous fistula, which in turn are associated with increased morbidity, mortality, and costs. Risk factors predisposing patients to these complications are both modifiable (procedure technique, medications, hemostasis method) and nonmodifiable (sex, age, body mass index, blood pressure, renal function). Patients’ risks can be reduced by nurses who are knowledgeable about these risk factors and identify complications before they become problematic.
Collapse
Affiliation(s)
- Nakia Merriweather
- Nakia Merriweather is a cardiology nurse in the echocardiography laboratory at the Hospital of the University of Pennsylvania, Philadelphia
| | - Linda M. Sulzbach-Hoke
- Linda M. Sulzbach-Hoke is a clinical nurse specialist on a 48-bed progressive care unit at the Hospital of the University of Pennsylvania, providing nursing care to adult cardiac patients. Her research and several of her publications support evidence-based nursing practice, specifically in patients undergoing percutaneous coronary intervention
| |
Collapse
|
75
|
Teng R, Butler K. Lack of clinically significant pharmacological interactions between ticagrelor and enoxaparin or unfractionated heparin in healthy subjects. J Clin Pharm Ther 2012; 37:704-11. [DOI: 10.1111/j.1365-2710.2012.01367.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
76
|
Sibbing D, Bernlochner I, Schulz S, Massberg S, Schömig A, Mehilli J, Kastrati A. Prognostic value of a high on-clopidogrel treatment platelet reactivity in bivalirudin versus abciximab treated non-ST-segment elevation myocardial infarction patients. ISAR-REACT 4 (Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment-4) platelet substudy. J Am Coll Cardiol 2012; 60:369-77. [PMID: 22682553 DOI: 10.1016/j.jacc.2012.02.044] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/08/2012] [Accepted: 02/23/2012] [Indexed: 11/24/2022]
Abstract
OBJECTIVES The ISAR-REACT 4 (Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment-4) platelet substudy aimed to determine the relevance of high on-clopidogrel treatment platelet reactivity (HPR) in non-ST-segment elevation myocardial infarction patients that received abciximab with unfractionated heparin (UFH) or bivalirudin during percutaneous coronary intervention (PCI). BACKGROUND In patients undergoing PCI, HPR has been linked to a higher risk for ischemic events. The influence of HPR on clinical outcomes may differ with regard to the adjunctive antithrombotic treatment administered. In ISAR-REACT 4, bivalirudin treatment showed similar efficacy profiles as compared to abciximab with UFH. The impact of HPR on clinical outcomes in abciximab with UFH versus bivalirudin treated non-ST-segment elevation myocardial infarction patients has never been investigated specifically. METHODS A total of 564 patients (274 in abciximab/UFH group vs. 290 in bivalirudin group) were enrolled in this study. Presence or absence of HPR following clopidogrel loading was determined by platelet function testing on a Multiplate analyzer (Verum Diagnostica, Munich, Germany). Per study group and stratified in HPR and no-HPR patients, the 30-day incidence of a combined efficacy endpoint (death, myocardial infarction, urgent target vessel revascularization) was determined. RESULTS For abciximab with UFH, the incidence of the efficacy endpoint was similar in HPR versus no-HPR patients (9.4% vs. 6.7%; odds ratio: 1.4; 95% confidence interval: 0.6 to 3.5; p = 0.43). For bivalirudin, the incidence of the efficacy endpoint was significantly higher in HPR versus no-HPR patients (22.0% vs. 5.0%; odds ratio: 5.4; 95% confidence interval: 2.4 to 12.1; p < 0.0001). CONCLUSIONS For patients with a risk profile similar to the subjects enrolled in this platelet substudy, the impact of HPR on clinical outcomes may depend on the type of adjunctive antithrombotic therapy used during PCI. Further investigations are warranted to clarify whether assessment of platelet function may help tailoring antithrombotic therapy during PCI.
Collapse
Affiliation(s)
- Dirk Sibbing
- Deutsches Herzzentrum München and 1. Medizinische Klinik, Klinikum rechts der Isar, Technische Universität München, Lazarettstrasse36, Munich, Germany.
| | | | | | | | | | | | | |
Collapse
|
77
|
|
78
|
Huttinger ZM, Milks MW, Nickoli MS, Aurand WL, Long LC, Wheeler DG, Dwyer KM, d'Apice AJF, Robson SC, Cowan PJ, Gumina RJ. Ectonucleotide triphosphate diphosphohydrolase-1 (CD39) mediates resistance to occlusive arterial thrombus formation after vascular injury in mice. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 181:322-33. [PMID: 22613024 DOI: 10.1016/j.ajpath.2012.03.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 02/09/2012] [Accepted: 03/08/2012] [Indexed: 12/26/2022]
Abstract
Modulation of purinergic signaling, which is critical for vascular homeostasis and the response to vascular injury, is regulated by hydrolysis of proinflammatory ATP and/or ADP by ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) to AMP, which then is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine. We report here that compared with littermate controls (wild type), transgenic mice expressing human ENTPDase-1 were resistant to the formation of an occlusive thrombus after FeCl(3)-induced carotid artery injury. Treatment of mice with the nonhydrolyzable ADP analog, adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S], negated the protection from thrombosis, consistent with a role for ADP in platelet recruitment and thrombus formation. ENTPD-1 expression decreased whole-blood aggregation after stimulation by ADP, an effect negated by adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S] stimulation, and limited the ability to maintain the platelet fibrinogen receptor, glycoprotein α(IIb)/β(3), in a fully activated state, which is critical for thrombus formation. In vivo treatment with a CD73 antagonist, a nonselective adenosine-receptor antagonist, or a selective A(2A) or A(2B) adenosine-receptor antagonist, negated the resistance to thrombosis in transgenic mice expressing human ENTPD-1, suggesting a role for adenosine generation and engagement of adenosine receptors in conferring in vivo resistance to occlusive thrombosis in this model. In summary, our findings identify ENTPDase-1 modulation of purinergic signaling as a key determinant of the formation of an occlusive thrombus after vascular injury.
Collapse
Affiliation(s)
- Zachary M Huttinger
- Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH 43210-1252, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
79
|
Ganetsky M, Babu KM, Salhanick SD, Brown RS, Boyer EW. Dabigatran: review of pharmacology and management of bleeding complications of this novel oral anticoagulant. J Med Toxicol 2012; 7:281-7. [PMID: 21887485 DOI: 10.1007/s13181-011-0178-y] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Dabigatran (Pradaxa) is a competitive direct thrombin inhibitor approved by the US FDA for prevention of embolic stroke in patients with nonvalvular atrial fibrillation. Dabigatran has a pharmacokinetic profile that produces predictable anticoagulation responses, does not undergo CYP 450 metabolism, has few drug-drug and drug-food interactions, and does not require frequent laboratory monitoring of clotting parameters. Clinicians are rapidly prescribing this agent as a replacement for warfarin therapy. However, no therapeutic agent has been accepted to reliably reverse the hemorrhagic complications of dabigatran. As of yet, there is no solid evidence to guide management of bleeding complications; management should start with local control of bleeding when possible and transfusion of pRBCs if needed. Transfusion of FFP would not be expected to help control bleeding. Limited and mixed data exist for transfusion of factor VIIa and prothrombin complex concentrates; these therapies should be considered as well as dialysis, which will increase elimination in patients with life-threatening or closed-space bleeding due to dabigatran. We present an article that reviews the pharmacokinetics, clinical trial literature, and consensus guidelines regarding this novel oral anticoagulant.
Collapse
Affiliation(s)
- Michael Ganetsky
- Department of Emergency Medicine, Beth Israel Deaconess Medical Center, WCC-2, Boston, MA 02215, USA.
| | | | | | | | | |
Collapse
|
80
|
Pfeilschifter W, Bohmann F, Baumgarten P, Mittelbronn M, Pfeilschifter J, Lindhoff-Last E, Steinmetz H, Foerch C. Thrombolysis with recombinant tissue plasminogen activator under dabigatran anticoagulation in experimental stroke. Ann Neurol 2012; 71:624-33. [DOI: 10.1002/ana.23558] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 01/16/2012] [Accepted: 02/01/2012] [Indexed: 11/07/2022]
|
81
|
Gallandat Huet RCG, de Vries AJ, Cernak V, Lisman T. Platelet function in stored heparinised autologous blood is not superior to in patient platelet function during routine cardiopulmonary bypass. PLoS One 2012; 7:e33686. [PMID: 22442710 PMCID: PMC3307748 DOI: 10.1371/journal.pone.0033686] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 02/15/2012] [Indexed: 11/19/2022] Open
Abstract
Background In cardiac surgery, cardiopulmonary bypass (CPB) and unfractionated heparin have negative effects on blood platelet function. In acute normovolemic haemodilution autologous unfractionated heparinised blood is stored ex-vivo and retransfused at the end of the procedure to reduce (allogeneic) transfusion requirements. In this observational study we assessed whether platelet function is better preserved in ex vivo stored autologous blood compared to platelet function in the patient during CPB. Methodology/Principal Finding We measured platelet aggregation responses pre-CPB, 5 min after the start of CPB, at the end of CPB, and after unfractionated heparin reversal, using multiple electrode aggregometry (Multiplate®) with adenosine diphosphate (ADP), thrombin receptor activating peptide (TRAP) and ristocetin activated test cells. We compared blood samples taken from the patient with samples taken from 100 ml ex-vivo stored blood, which we took to mimick blood storage during normovolemic haemodilution. Platelet function declined both in ex-vivo stored blood as well as in blood taken from the patient. At the end of CPB there were no differences in platelet aggregation responses between samples from the ex vivo stored blood and the patient. Conclusion/Significance Ex vivo preservation of autologous blood in unfractionated heparin does not seem to be profitable to preserve platelet function.
Collapse
Affiliation(s)
- Rolf C G Gallandat Huet
- Department of Anesthesiology, University of Groningen, University Medical Center Groningen, The Netherlands.
| | | | | | | |
Collapse
|
82
|
Yu K, Lai BFL, Kizhakkedathu JN. Carbohydrate structure dependent hemocompatibility of biomimetic functional polymer brushes on surfaces. Adv Healthc Mater 2012. [PMID: 23184724 DOI: 10.1002/adhm.201100042] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Glycocalyx mimicking glycopolymer brushes presenting mannose, galactose and glucose residues in the pyranose form, similar to those present on cell surfaces, were synthesized on planar substrates (Si wafer, gold chip) and monodispersed polystyrene (PS) particles, and the interaction of blood to these surfaces were studied using various methods with the goal of producing a hemocompatible surface. Surface plasmon resonance (SPR) spectroscopy and gel analyses showed that the total protein adsorption from plasma was greatly reduced, as low as 24.3 ng/cm(2) from undiluted plasma on the glucose carrying brush. The protein adsorption decreased with increasing grafting density of the brushes. It was also found that the protein adsorption varied with the anticoagulant used for blood collection; much higher amount of protein was adsorbed from heparinzied plasma than citrated plasma. Proteomics protein identification analysis revealed that protein adsorption from plasma depended on the type of sugar residue present on the surface as well as the type of anticoagulant. All the three types of glycopolymer brushes showed similar level of platelet activation as that of buffer control irrespective of the nature of carbohydrate residue. However, the number of adhered platelet and their morphology depended on the type of carbohydrate residue present on the brush. On glucose brush, the extent of platelet adhesion and spreading was significantly lowered compared to other brushes. All the glycopolymer brushes were neutral to blood coagulation as indicated by thromboelastography analysis. The glucose brush gave a slightly longer initial coagulation time suggesting that this surface may be more biocompatible. Our data demonstrate that the structure of carbohydrate residue is an important factor in the design of synthetic blood contacting surface based on glycopolymer.
Collapse
Affiliation(s)
- Kai Yu
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | | | | |
Collapse
|
83
|
Silvain J, Beygui F, Barthélémy O, Pollack C, Cohen M, Zeymer U, Huber K, Goldstein P, Cayla G, Collet JP, Vicaut E, Montalescot G. Efficacy and safety of enoxaparin versus unfractionated heparin during percutaneous coronary intervention: systematic review and meta-analysis. BMJ 2012; 344:e553. [PMID: 22306479 PMCID: PMC3271999 DOI: 10.1136/bmj.e553] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/19/2012] [Indexed: 01/11/2023]
Abstract
OBJECTIVE To determine the efficacy and safety of enoxaparin compared with unfractionated heparin during percutaneous coronary intervention. DESIGN Systematic review and meta-analysis. DATA SOURCES Medline and Cochrane database of systematic reviews, January 1996 to May 2011. STUDY SELECTION Randomised and non-randomised studies comparing enoxaparin with unfractionated heparin during percutaneous coronary intervention and reporting on both mortality (efficacy end point) and major bleeding (safety end point) outcomes. DATA EXTRACTION Sample size, characteristics, and outcomes, extracted independently and analysed. DATA SYNTHESIS 23 trials representing 30,966 patients were identified, including 10,243 patients (33.1%) undergoing primary percutaneous coronary intervention for ST elevation myocardial infarction, 8750 (28.2%) undergoing secondary percutaneous coronary intervention after fibrinolysis, and 11,973 (38.7%) with non-ST elevation acute coronary syndrome or stable patients scheduled for percutaneous coronary intervention. A total of 13,943 patients (45.0%) received enoxaparin and 17,023 (55.0%) unfractionated heparin. Enoxaparin was associated with significant reductions in death (relative risk 0.66, 95% confidence interval 0.57 to 0.76; P<0.001), the composite of death or myocardial infarction (0.68, 0.57 to 0.81; P<0.001), and complications of myocardial infarction (0.75, 0.6 to 0.85; P<0.001), and a reduction in incidence of major bleeding (0.80, 0.68 to 0.95; P=0.009). In patients who underwent primary percutaneous coronary intervention, the reduction in death (0.52, 0.42 to 0.64; P<0.001) was particularly significant and associated with a reduction in major bleeding (0.72, 0.56 to 0.93; P=0.01). CONCLUSION Enoxaparin seems to be superior to unfractionated heparin in reducing mortality and bleeding outcomes during percutaneous coronary intervention and particularly in patients undergoing primary percutaneous coronary intervention for ST elevation myocardial infarction.
Collapse
Affiliation(s)
- Johanne Silvain
- Institut de Cardiologie, Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
84
|
Vakil NH, Kanaan AO, Donovan JL. Heparin-induced thrombocytopenia in the pediatric population: a review of current literature. J Pediatr Pharmacol Ther 2012; 17:12-30. [PMID: 23118656 PMCID: PMC3428184 DOI: 10.5863/1551-6776-17.1.12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Heparin-induced thrombocytopenia is a rare and serious reaction to unfractionated heparin and low-molecular-weight heparins in children. Quick recognition, discontinuation of heparin, and subsequent treatment with an alternative anticoagulant are essential steps to prevent serious complications such as thrombus and limb amputation. The purpose of this review is to describe the clinical features of heparin-induced thrombocytopenia in children and to summarize the data available for its management. This paper summarizes data and relates the use of direct thrombin inhibitors with clinical outcomes. A literature search was conducted with Ovid, using the key terms argatroban, bivalirudin, hirulog, danaparoid, lepirudin, direct thrombin inhibitor, heparin-induced thrombocytopenia, thrombosis, warfarin, and fondaparinux. Articles were excluded if they were classified as editorials, review articles, or conference abstracts or if they involved patients 18 years of age or older or described disease states not related to thrombosis. Nineteen articles containing 33 case reports were identified and evaluated for this review. Of the 33 cases, 14, 10, 4, and 2 cases described the use of lepirudin, danaparoid, argatroban, and bivalirudin, respectively. Two cases did not report the type of anticoagulant used, and 1 case used aspirin. The most commonly reported complication was bleeding.
Collapse
Affiliation(s)
- Niyati H. Vakil
- Massachusetts College of Pharmacy and Health Sciences, Worcester, Massachusetts
| | - Abir O. Kanaan
- Massachusetts College of Pharmacy and Health Sciences, Worcester, Massachusetts
| | - Jennifer L. Donovan
- Massachusetts College of Pharmacy and Health Sciences, Worcester, Massachusetts
| |
Collapse
|
85
|
Lilly SM, Wilensky RL. Emerging therapies for acute coronary syndromes. Front Pharmacol 2011; 2:61. [PMID: 22028691 PMCID: PMC3199568 DOI: 10.3389/fphar.2011.00061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 09/25/2011] [Indexed: 01/15/2023] Open
Abstract
In the majority of cases acute coronary syndromes (ACS) are caused by activation and aggregation of platelets and subsequent thrombus formation leading to a decrease in coronary artery blood flow. Recent focus on the treatment of ACS has centered on reducing the response of platelets to vascular injury as well as inhibiting fibrin deposition. Novel therapies include more effective P2Y12 receptor blockers thereby reducing inter-individual variability, targeting the platelet thrombin receptor (protease activated receptor 1) as well as directly inhibiting factor Xa or thrombin activity. In this review we discuss the clinical data evaluating the effectiveness of these various new ACS treatment options.
Collapse
Affiliation(s)
- Scott M Lilly
- Cardiovascular Division, Hospital of the University of Pennsylvania Philadelphia, PA, USA
| | | |
Collapse
|
86
|
Abstract
Heparins and vitamin K antagonists have been the primary agents used for anticoagulation in certain cardiovascular and thromboembolic diseases for over 50 years. However, they can be difficult to administer and are fraught with limitations. In response to the need for new anticoagulants, direct thrombin inhibitors (DTIs) have been developed and investigated for their utility in prophylaxis and treatment of venous thromboembolism (VTE), heparin-induced thrombocytopenia (HIT), acute coronary syndromes (ACS), secondary prevention of coronary events after ACS, and nonvalvular atrial fibrillation. Currently, four parenteral direct inhibitors of thrombin activity are FDA-approved in North America: lepirudin, desirudin, bivalirudin and argatroban. Of the new oral DTIs, dabigatran etexilate is the most studied and promising of these agents. This review discusses the clinical indications and efficacy of these direct thrombin inhibitors as well as future directions in anticoagulant therapy.
Collapse
Affiliation(s)
- Catherine J Lee
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, USA.
| | | |
Collapse
|
87
|
Montalescot G, Zeymer U, Silvain J, Boulanger B, Cohen M, Goldstein P, Ecollan P, Combes X, Huber K, Pollack C, Bénezet JF, Stibbe O, Filippi E, Teiger E, Cayla G, Elhadad S, Adnet F, Chouihed T, Gallula S, Greffet A, Aout M, Collet JP, Vicaut E. Intravenous enoxaparin or unfractionated heparin in primary percutaneous coronary intervention for ST-elevation myocardial infarction: the international randomised open-label ATOLL trial. Lancet 2011; 378:693-703. [PMID: 21856483 DOI: 10.1016/s0140-6736(11)60876-3] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction has traditionally been supported by unfractionated heparin, which has never been directly compared with a new anticoagulant using consistent anticoagulation and similar antiplatelet strategies in both groups. We compared traditional heparin treatment with intravenous enoxaparin in primary PCI. METHODS In a randomised open-label trial, patients presenting with ST-elevation myocardial infarction were randomly assigned (1:1) to receive an intravenous bolus of 0·5 mg/kg of enoxaparin or unfractionated heparin before primary PCI. Wherever possible, medical teams travelling in mobile intensive care units (ambulances) selected, randomly assigned (using an interactive voice response system at the central randomisation centre), and treated patients. Patients who had received any anticoagulant before randomisation were excluded. Patients and caregivers were not masked to treatment allocation. The primary endpoint was 30-day incidence of death, complication of myocardial infarction, procedure failure, or major bleeding. The main secondary endpoint was the composite of death, recurrent acute coronary syndrome, or urgent revascularisation. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT00718471. FINDINGS 910 patients were assigned to treatment with enoxaparin (n=450) or unfractionated heparin (n=460). The primary endpoint occurred in 126 (28%) patients after anticoagulation with enoxaparin versus 155 (34%) patients on unfractionated heparin (relative risk [RR] 0·83, 95% CI 0·68-1·01, p=0·06). The incidence of death (enoxaparin, 17 [4%] vs heparin, 29 [6%] patients; p=0·08), complication of myocardial infarction (20 [4%] vs 29 [6%]; p=0·21), procedure failure (100 [26%] vs 109 [28%]; p=0·61), and major bleeding (20 [5%] vs 22 [5%]; p=0·79) did not differ between groups. Enoxaparin resulted in a significantly reduced rate of the main secondary endpoint (30 [7%] vs 52 [11%] patients; RR 0·59, 95% CI 0·38-0·91, p=0·015). Death, complication of myocardial infarction, or major bleeding (46 [10%] vs 69 [15%] patients; p=0·03), death or complication of myocardial infarction (35 [8%] vs 57 [12%]; p=0·02), and death, recurrent myocardial infarction, or urgent revascularisation (23 [5%] vs 39 [8%]; p=0·04) were all reduced with enoxaparin. INTERPRETATION Intravenous enoxaparin compared with unfractionated heparin significantly reduced clinical ischaemic outcomes without differences in bleeding and procedural success. Therefore, enoxaparin provided an improvement in net clinical benefit in patients undergoing primary PCI. FUNDING Direction de la Recherche Clinique, Assistance Publique-Hôpitaux de Paris; Sanofi-Aventis.
Collapse
Affiliation(s)
- Gilles Montalescot
- Institut de Cardiologie, CHU Pitié-Salpêtrière (AP-HP), Université Paris 6, Paris, France.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
88
|
Wright RS, Anderson JL, Adams CD, Bridges CR, Casey DE, Ettinger SM, Fesmire FM, Ganiats TG, Jneid H, Lincoff AM, Peterson ED, Philippides GJ, Theroux P, Wenger NK, Zidar JP, Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE, Chavey WE, Fesmire FM, Hochman JS, Levin TN, Lincoff AM, Peterson ED, Theroux P, Wenger NK, Zidar JP. 2011 ACCF/AHA focused update incorporated into the ACC/AHA 2007 Guidelines for the Management of Patients with Unstable Angina/Non-ST-Elevation Myocardial Infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines developed in collaboration with the American Academy of Family Physicians, Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons. J Am Coll Cardiol 2011; 57:e215-367. [PMID: 21545940 DOI: 10.1016/j.jacc.2011.02.011] [Citation(s) in RCA: 301] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
89
|
Effect of clopidogrel pretreatment on ischemic complications of percutaneous coronary intervention among bivalirudin-treated patients (from the EVENT registry). Am J Cardiol 2011; 107:1751-6. [PMID: 21640216 DOI: 10.1016/j.amjcard.2011.02.331] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 02/07/2011] [Accepted: 02/07/2011] [Indexed: 01/08/2023]
Abstract
Although clopidogrel pretreatment benefits patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes, these benefits are less well established among patients undergoing elective PCI--in particular, when they are treated with the direct thrombin inhibitor, bivalirudin. We used data from the multicenter Evaluation of Drug Eluting stents and ischemic Events registry to assess the association between clopidogrel pretreatment and PCI-related complications among patients undergoing elective PCI with bivalirudin as the antithrombotic regimen. The primary end point was the composite of in-hospital death or myocardial infarction. From January 2005 and December 2007, 4,681 patients underwent elective PCI at 55 United States centers, and 1,913 (41%) received bivalirudin as the planned anticoagulant. Clopidogrel pretreatment was used in 923 patients (48%). The incidence of in-hospital death or myocardial infarction was similar among patients who did and did not receive clopidogrel pretreatment (5.5% vs 5.8%, p = 0.83). This result was unchanged in propensity-adjusted analyses (adjusted odds ratio for pretreatment 0.91, 95% confidence interval 0.60 to 1.39, p = 0.66). Also, no differences were seen in the in-hospital bleeding events (1.0% vs 1.0%, p = 0.94) or 1-year ischemic complications between the 2 treatment groups (7.5% vs 8.3%, p = 0.26). In conclusion, among unselected patients undergoing elective PCI with bivalirudin as the planned anticoagulant, clopidogrel pretreatment was common but was not associated with a reduced risk of ischemic complications.
Collapse
|
90
|
Vranckx P, Valgimigli M, Serruys P. Looking back into the future: desirudin in acute coronary syndromes and coronary stenting. EUROINTERVENTION 2011; 7:263-9. [PMID: 21646070 DOI: 10.4244/eijv7i2a42] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Although percutaneous coronary intervention (PCI) is a highly effective modality for the management of acute coronary syndromes, it can potentiate the existing prothrombotic state around lesion areas and lead to ischaemic complications. Adjunctive pharmacologic treatment with heparin reduces the risk of ischaemic events, but the utility of heparin is limited by its unpredictable pharmacodynamic effects and its inability to modulate fibrin-bound thrombin. Additionally, a potential risk of heparin-induced thrombocytopenia is associated with heparin use. Direct thrombin inhibitors (DTIs) have emerged as potential alternatives to heparin in patients undergoing PCI. Bivalirudin is a DTI indicated for use in PCI. Results from various studies have suggested clinical benefit associated with the use of bivalirudin, driven primarily by the reduction in bleeding risks compared with the standard treatment regimens. Of concern, however, is a significant increase in acute stent thrombosis with bivalirudin monotherapy compared with heparin plus GPIIb/IIIa inhibitors following primary PCI for ST-segment elevation myocardial infarction (STEMI). Desirudin is a highly potent DTI with greater binding affinity than bivalirudin for thrombin. This report provides a comparative overview of the pharmacology and clinical utility of desirudin and bivalirudin in the setting of PCI.
Collapse
Affiliation(s)
- Pascal Vranckx
- Department of Cardiac Intensive Care and Interventional Cardiology, Hartcentrum Hasselt, Hasselt, Belgium
| | | | | |
Collapse
|
91
|
Rybak I, Ehle M, Buckley L, Fanikos J. Efficacy and safety of novel anticoagulants compared with established agents. Ther Adv Hematol 2011; 2:175-95. [PMID: 23556088 PMCID: PMC3573404 DOI: 10.1177/2040620711408489] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Dabigatran, rivaroxaban, and apixaban are novel oral anticoagulants that offer major advantages over existing agents. The onset of the anticoagulant effect of these agents is rapid. Each agent has a predictable anticoagulant response that eliminates the need for monitoring. Clinical trials have been completed with all three agents in the prevention and treatment of the three leading causes of cardiovascular death: myocardial infarction, stroke, and venous thromboembolism (VTE). Novel agents have shown reduced or similar rates of thrombosis, major bleeding, and adverse events when weighed against either low molecular weight heparin or warfarin. Additional trials are underway and more agents are in development. As a result, novel anticoagulants may impact physician prescribing practices and warrant consideration in patients requiring thrombosis management.
Collapse
Affiliation(s)
- Iwona Rybak
- Department of Pharmacy, Brigham and Women's Hospital, Boston, MA, USA
| | - Michael Ehle
- Department of Pharmacy, Brigham and Women's Hospital, Boston, MA, USA
| | - Leo Buckley
- Department of Pharmacy, Brigham and Women's Hospital, Boston, MA, USA
| | - John Fanikos
- Department of Pharmacy, Brigham and Women's Hospital, Boston, MA, USA
| |
Collapse
|
92
|
Abstract
INTRODUCTION Both arterial and venous thromboembolism constitute a significant disease burden worldwide, leading to major use of healthcare resources. As anticoagulants play a pivotal role in the treatment of these disorders, it is vital for healthcare providers to have sufficient knowledge of their biochemical and clinical attributes. AREAS COVERED Enoxaparin is one of the most commonly used low-molecular-weight heparins in a wide variety of thromboembolic disorders and has several advantages over unfractionated heparin. An analysis of its biophysical profile, with special emphasis on pharmacokinetic and pharmacodynamic properties, is undertaken in this article. In addition, most recent major clinical studies elucidating its role in common thromboembolic conditions are discussed, while keeping the historical perspective at hand. Readers will be able to understand the pharmacologic properties of enoxaparin with their clinical relevance for day-to-day use and critically analyze the amount and weight of scientific evidence behind its use in various disorders. EXPERT OPINION In summary, enoxaparin has been shown, by a vast amount of scientific data, to be a safe and effective agent in the treatment of a whole spectrum of acute coronary syndromes, with similar efficacy and safety in the prevention and treatment of venous thromboembolism.
Collapse
Affiliation(s)
- Zafar Iqbal
- Newark Beth Israel Medical Center, Newark, NJ 07112, USA
| | | |
Collapse
|
93
|
Heparin promotes platelet responsiveness by potentiating αIIbβ3-mediated outside-in signaling. Blood 2011; 117:4946-52. [PMID: 21368290 DOI: 10.1182/blood-2010-09-307751] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Unfractionated heparin (UFH) is a widely used anticoagulant that has long been known to potentiate platelet responses to subthreshold doses of platelet agonists. UFH has been reported to bind and induce modest conformational changes in the major platelet integrin, αIIbβ3, and induce minor changes in platelet morphology. The mechanism by which UFH elicits these platelet-activating effects, however, is not well understood. We found that both human and murine platelets exposed to UFH, either in solution or immobilized onto artificial surfaces, underwent biochemical and morphologic changes indicative of a potentiated state, including phosphorylation of key cytosolic signaling molecules and cytoskeletal changes leading to cell spreading. Low molecular weight heparin and the synthetic pentasaccharide, fondaparinux, had similar platelet-potentiating effects. Human or mouse platelets lacking functional integrin αIIbβ3 complexes and human platelets pretreated with the fibrinogen receptor antagonists eptifibatide or abciximab failed to become potentiated by heparin, demonstrating that heparin promotes platelet responsiveness via its ability to initiate αIIbβ3-mediated outside-in signaling. Taken together, these data provide novel insights into the mechanism by which platelets become activated after exposure to heparin and heparin-coated surfaces, and suggest that currently used glycoprotein IIb-IIIa inhibitors may be effective inhibitors of nonimmune forms of heparin-induced platelet activation.
Collapse
|
94
|
Heparin-associated anti-Xa activity and platelet-derived prothrombotic and proinflammatory biomarkers in moderate to high-risk patients with acute coronary syndrome. J Thromb Thrombolysis 2011; 31:146-53. [PMID: 21086021 DOI: 10.1007/s11239-010-0532-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Heparin compounds, to include fractionated and unfractionated preparations, exert both antithrombotic and antiinflammatory effects through combined inhibition of factor Xa and thrombin. The contribution of modulated platelet activity in vivo is less clearly defined. The SYNERGY library was a prospectively designed repository for candidate clinical, hemostatic, platelet, and molecular biomarkers from patients participating in SYNERGY--a large-scale, randomized clinical trial evaluating the comparative benefits of unfractionated heparin (UFH) and enoxaparin in high-risk patients with acute coronary syndrome (ACS). Samples were collected from 201 patients enrolled at 26 experienced, participating sites and shipped to established core laboratories for analysis of platelet, endothelium-derived, inflammatory and coagulation activity biomarkers. Tissue factor pathway inhibitor (TFPI)--a vascular endothelial cell-derived factor Xa regulatory protein-correlated directly with plasma anti-Xa activity (unadjusted: r = 0.23, P < 0.0001; adjusted: β = 0.10; P = 0.001), as did TFPI-fXa complexes (unadjusted: r = 0.34, P < 0.0001; adjusted: β = 0.38; P = < 0.0001). In contrast, there was a direct and inverse relationship between anti-Xa activity and two platelet-derived biomarkers-plasminogen activator inhibitor-1 (unadjusted: r = -0.18, P = 0.0012; adjusted: β = -0.10; P = 0.021) and soluble CD40 ligand (unadjusted: r = -0.11, P = 0.05; adjusted: β = -0.13; P = 0.049). All measured analyte relationships persisted after adjustment for age, creatinine clearance, weight, sex, and duration of treatment. Differences in biomarkers between patients receiving UFH and those randomized to enoxaparin were not observed. The ability of heparin compounds to affect the prothrombotic and proinflammatory states which characterize ACS may involve factor Xa-related modulation of platelet activation and expression. Whether this potentially beneficial effect is direct or indirect and achieved, at least in part, through the release of endothelial cell-derived coagulation regulatory proteins will require further investigation.
Collapse
|
95
|
Antithrombin-heparin covalent complex reduces microemboli during cardiopulmonary bypass in a pig model. Blood 2010; 116:5716-23. [DOI: 10.1182/blood-2010-05-284448] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractTranscranial Doppler-detected high-intensity transient signals (HITS) during cardiopulmonary bypass (CPB) surgery have been associated with postoperative neurocognitive dysfunction, suggesting microemboli in the brain could be a contributing factor. HITS occur despite administration of unfractionated heparin (UFH). This study was done to determine whether antithrombin-heparin covalent complex (ATH), a more potent anticoagulant than heparin, can reduce HITS during CPB. In a pig CPB model, ATH, UFH, or UFH + antithrombin (AT) was intravenously administered to female Yorkshire pigs after sternotomy. Twenty minutes later, hypothermic CPB was initiated and continued for 1.25 hours, then normothermia was re-established for 45 minutes. Protamine sulfate was given to neutralize the anticoagulants, and pigs were allowed to recover. HITS were monitored using an arterial flow probe placed over the carotid artery. Compared with UFH (300 or 1000 U/kg), ATH reduced the number of HITS during CPB in a dose-dependent manner. AT (3 mg/kg) + UFH (300 U/kg) resulted in an intermediate HITS rate between UFH and ATH (2 mg/kg in terms of AT). Examination of brain sections for emboli formation confirmed that, similar to HITS, number of thrombi decreased in direct proportion to ATH dosage. These results support the hypotheses that the majority of HITS represent thromboemboli and that ATH reduces emboli formation during CPB.
Collapse
|
96
|
Novel Anticoagulants for Stroke Prevention in Atrial Fibrillation. J Am Coll Cardiol 2010; 56:2067-76. [DOI: 10.1016/j.jacc.2010.09.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 09/13/2010] [Accepted: 09/23/2010] [Indexed: 12/11/2022]
|
97
|
Thompson KA, Philip KJ, Schwarz ER. Clinical Applications of Bivalirudin in the Cardiac Catheterization Laboratory. J Cardiovasc Pharmacol Ther 2010; 16:140-9. [DOI: 10.1177/1074248410385682] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Heparin has been used in the catheterization laboratory to prevent ischemic complications of percutaneous coronary intervention (PCI). Bivalirudin, a direct thrombin inhibitor, is an anticoagulant that has several pharmacologic advantages over heparin, and it has been proposed that bivalirudin is superior to heparin in its ability to prevent bleeding complications of PCI. As such, there have been a variety of large prospective clinical trials comparing bivalirudin and heparin over the past 13 years. The results of these trials have prompted the general acceptance of bivalirudin as a safe alternative to heparin use during PCI, and bivalirudin has been given a class 1 recommendation by the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for a variety of clinical indications. This article will review the data supporting the use of bivalirudin in the cardiac catheterization laboratory and describe several advantages of bivalirudin over traditional heparin use. We also include a discussion of the use of bivalirudin in conjunction with other medications that are frequently used in the catheterization laboratory. We end with an analysis of the economic differences between bivalirudin and heparin and the impact that financial factors may have on the choice of anticoagulant.
Collapse
Affiliation(s)
- Keith A. Thompson
- Division of Cardiology, Department of Medicine, Cedars Sinai Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - Kiran J. Philip
- Division of Cardiology, Department of Medicine, Cedars Sinai Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - Ernst R. Schwarz
- Division of Cardiology, Department of Medicine, Cedars Sinai Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA,
| |
Collapse
|
98
|
Velu S, Lip GYH. Recent progress in antithrombotic therapy for atrial fibrillation. J Atheroscler Thromb 2010; 18:257-73. [PMID: 21088368 DOI: 10.5551/jat.7153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Atrial fibrillation (AF) is becoming a major health care burden as elderly populations increase. The increased risk of stroke and thromboembolisms in patients with AF is well documented and anti-coagulation with adjusted-dose warfarin is highly effective in reducing stroke risk, being superior to antiplatelet agents. Despite recognition of the epidemiological problem and the sound evidence base for thromboprophylaxis, as well as major guidelines recommending treatment, anticoagulation use is still suboptimal, given the dis-utility and limitations associated with warfarin. Recent developments in thromboprophylaxis for AF include efforts for better risk stratification for predictions of thromboembolic risk. Constant efforts are underway to develop newer, less cumbersome, alternatives to warfarin with similar (or better) efficacy. This review article provides an overview of the recent progress made, the potential challenges involved and the future of these therapeutic approaches.
Collapse
Affiliation(s)
- Selvakumar Velu
- University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK
| | | |
Collapse
|
99
|
Cho JS, Her SH, Baek JY, Park MW, Kim HD, Jeong MH, Ahn YK, Chae SC, Hur SH, Hong TJ, Kim YJ, Seong IW, Chae JK, Rhew JY, Chae IH, Cho MC, Bae JH, Rha SW, Kim CJ, Choi D, Jang YS, Yoon J, Chung WS, Cho JG, Seung KB, Park SJ. Clinical benefit of low molecular weight heparin for ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention with glycoprotein IIb/IIIa inhibitor. J Korean Med Sci 2010; 25:1601-8. [PMID: 21060749 PMCID: PMC2966997 DOI: 10.3346/jkms.2010.25.11.1601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 06/16/2010] [Indexed: 11/20/2022] Open
Abstract
The efficacy of low molecular weight heparin (LMWH) with low dose unfractionated heparin (UFH) during percutaneous coronary intervention (PCI) with or without glycoprotein (Gp) IIb/IIIa inhibitor compared to UFH with or without Gp IIb/IIIa inhibitor has not been elucidated. Between October 2005 and July 2007, 2,535 patients with ST elevation acute myocardial infarction (STEMI) undergoing PCI in the Korean Acute Myocardial Infarction Registry (KAMIR) were assigned to either of two groups: a group with Gp IIb/IIIa inhibitor (n=476) or a group without Gp IIb/IIIa inhibitor (n=2,059). These groups were further subdivided according to the use of LMWH with low dose UFH (n=219) or UFH alone (n=257). The primary end points were cardiac death or myocardial infarction during the 30 days after the registration. The primary end point occurred in 4.1% (9/219) of patients managed with LMWH during PCI and Gp IIb/IIIa inhibitor and 10.8% (28/257) of patients managed with UFH and Gp IIb/IIIa inhibitor (odds ratio [OR], 0.290; 95% confidence interval [CI], 0.132-0.634; P=0.006). Thrombolysis In Myocardial Infarction (TIMI) with major bleeding was observed in LMHW and UFH with Gp IIb/IIIa inhibitor (1/219 [0.5%] vs 1/257 [0.4%], P=1.00). For patients with STEMI managed with a primary PCI and Gp IIb/IIIa inhibitor, LMWH is more beneficial than UFH.
Collapse
Affiliation(s)
- Jung Sun Cho
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Sung-Ho Her
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Ju Yeal Baek
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Mahn-Won Park
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Hyoung Doo Kim
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Myung Ho Jeong
- Cardiovascular Center, Chonnam National University Hospital, Gwangju, Korea
| | - Young keun Ahn
- Cardiovascular Center, Chonnam National University Hospital, Gwangju, Korea
| | - Shung Chull Chae
- Cardiovascular Center, Kyungpook National University, Daegu, Korea
| | - Seung Ho Hur
- Cardiovascular Center, Keimyung University Dongsan Medical Center, Daegu, Korea
| | - Taek Jong Hong
- Cardiovascular Center, Pusan National University Hospital, Busan, Korea
| | - Young Jo Kim
- Cardiovascular Center, Yeungnam University Hostpial, Daegu, Korea
| | - In Whan Seong
- Cardiovascular Center, Chungnam National University Hostpial, Daejon, Korea
| | - Jei Keon Chae
- Cardiovascular Center, Chonbuk National University Hospital, Jeonju, Korea
| | - Jay Young Rhew
- Cardiovascular Center, Jeonju Presbyterian Medical Center, Jeonju, Korea
| | - In Ho Chae
- Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Myeong Chan Cho
- Cardiovascular Center, Chungbuk National University, Cheongju, Korea
| | - Jang Ho Bae
- Cardiovascular Center, Konyang University, Daejon, Korea
| | - Seung Woon Rha
- Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea
| | - Chong Jim Kim
- Cardiovascular Center, Kyunghee University Hospital, Seoul, Korea
| | - Donghoon Choi
- Cardiovascular Center, Yonsei University Hospital, Seoul, Korea
| | - Yang Soo Jang
- Cardiovascular Center, Yonsei University Hospital, Seoul, Korea
| | - Junghan Yoon
- Cardiovascular Center, Wonju University Hospital, Wonju, Korea
| | - Wook Sung Chung
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Jeong Gwan Cho
- Cardiovascular Center, Chonnam National University Hospital, Gwangju, Korea
| | - Ki Bae Seung
- Cardiovascular Center, Seoul St. Mary's Hospital, Seoul, Korea
| | - Seung Jung Park
- Cardiovascular Center, Ulsan University Asan Medical Center, Seoul, Korea
| | | |
Collapse
|
100
|
Nonimmune Heparin–Platelet Interactions: Implications for the Pathogenesis of Heparin-Induced Thrombocytopenia. ACTA ACUST UNITED AC 2010. [DOI: 10.3109/9781420045093.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|