Comparison of bivalirudin vs heparin plus glycoprotein IIb/IIIa inhibitors in patients undergoing an invasive strategy: a meta-analysis of randomized clinical trials. Int J Cardiol. 2011;152:369-374. [PMID: 20843568 DOI: 10.1016/j.ijcard.2010.08.007]

Practicability of Bivalirudin plus Glycoprotein IIb/IIIa Inhibitors in Patients Undergoing Percutaneous Coronary Intervention: A Meta-Analysis

A variety of antithrombotic drugs are used during percutaneous coronary interventions (PCIs). We aimed to investigate the practicability of the use of bivalirudin and GPIs in patients receiving PCI. We searched 7 of 629 relevant records from PubMed, the Cochrane Library, EMBASE, and Web of Science for randomised controlled trials. There were no significant differences in the rates of major adverse cardiac events (MACE) between bivalirudin plus GPI and heparin (all P  >  .05). Bivalirudin plus planned GPI was similar to bivalirudin monotherapy in terms of the risk of MACE (risk ratio [RR] = 1.07; 95% confidence interval [CI] = .91 − 1.27; P = .55). Bivalirudin plus provisional GPI was associated with lower bleeding risk (RR = .57; 95% CI = .47 − .69; P < .01) compared to using heparin plus GPI. Compared to bivalirudin alone, bivalirudin plus planned GPI evidently increased bleeding risk (RR = 2.20; 95% CI = 1.73 − 2.79; P < .01). Patients receiving bivalirudin or heparin therapy had semblable efficacy endpoints, but those receiving bivalirudin had a significantly lower bleeding risk. For high-risk bleeding patients, bivalirudin plus provisional GPI can have a better antithrombotic effect than heparin, without increasing the bleeding risk.

Management of heparin-induced thrombocytopenia: systematic reviews and meta-analyses

Heparin-induced thrombocytopenia (HIT) is a prothrombotic adverse drug reaction occurring in <0.1% to 7% of patients receiving heparin products depending on the patient population and type of heparin. Management of HIT is highly dependent on a sequence of tests for which clinicians may or may not have the results when care decisions need to be made. We conducted systematic reviews of the effects of management strategies in persons with acute HIT, subacute HIT A or B, and remote HIT. We searched Medline, EMBASE, and the Cochrane Database through July 2019 for previously published systematic reviews and primary studies. Two investigators independently screened and extracted data and assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. We found primarily noncomparative studies and case series assessing effects of treatments, which led to low to very low certainty evidence. There may be little to no difference in the effects between nonheparin parenteral anticoagulants and direct oral anticoagulants in acute HIT. The benefits of therapeutic-intensity may be greater than prophylactic-intensity anticoagulation. Using inferior vena cava filters or platelet transfusion may result in greater harm than not using these approaches. Evidence for management in special situations, such as for patients undergoing cardiovascular interventions or renal replacement therapy, was also low to very low certainty. Additional research to evaluate nonheparin anticoagulants is urgently needed, and the development of novel treatments that reduce thrombosis without increasing hemorrhage should be a priority.

Heparin-induced thrombocytopenia in renal insufficiency undergoing dialysis and percutaneous coronary intervention after acute myocardial infarction: A case report

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is a rare complication of heparin therapy, and is characterized by arteriovenous thrombosis and bleeding events. The incidence of HIT after percutaneous coronary intervention (PCI) in patients with myocardial infarction complicated with renal failure is rarely reported.

CASE SUMMARY

We report a 73-year-old man with acute myocardial infarction and renal failure who underwent hemodialysis and PCI, and developed a progressive decline in platelets and subcutaneous hemorrhage of both upper limbs after heparin treatment. In addition to a gradual decrease in platelets, the patient’s 4T's score was 7, and HIT antibody was positive, confirming the diagnosis of HIT.

CONCLUSION

Patients receiving heparin combined with antiplatelet therapy should be monitored closely, especially for their platelet count. In the case of thrombo-cytopenia, HIT should be highly suspected. When the diagnosis of HIT is confirmed, timely individualized treatment should be delivered.

Efficacy and safety of bivalirudin vs heparin in patients with coronary heart disease undergoing percutaneous coronary intervention: A meta-analysis of randomized controlled trials

BACKGROUND

This meta-analysis is to evaluate the efficacy and safety of bivalirudin in patients with ST-elevation myocardial infarction (STEMI).

METHODS

PubMed, Cochrane Library, Embase, CNKI, CBMdisc, and VIP database were searched. Randomized controlled trial (RCT) was selected and the meta-analysis was conducted by RevMan 5.1. The primary efficacy endpoint was the incidence of major adverse cardiovascular events (MACE) and the primary safety endpoint was the incidence of major bleeding. Secondary efficacy endpoints were myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis (ST), stock, mortality, and thrombocytopenia. The pooled risk ratios (RRs) with the corresponding 95% confidence intervals (CI) were used to assess the efficacy and safety of bivalirudin vs heparin.

RESULTS

Seven RCTs met the inclusion criteria, and 16,640 patients were included. We found that bivalirudin associated with lower risk of mortality (RR = 1.05; 95% CI = 0.74-1.49; P = .03; I = 2%), major bleeding (RR = 0.64; 95% CI = 0.54-0.75; P < .00001; I = 70%) and thrombocytopenia (RR = 0.39; 95% CI = 0.25-0.61; P < .0001; I = 0) compared with heparin. However, the use of bivalirudin increase the risk of MI(RR = 1.37; 95% CI = 1.10-1.71; P = .004; I = 25%) and ST(RR = 1.61; 95% CI = 1.05-2.47; P = .03; I = 70%) and has similar risk of MACE (RR = 1.00; 95% CI = 0.90-1.11; P = .97; I = 16%), TVR (RR = 1.43; 95% CI = 0.92-2.22; P = .11; I = 46%) and stock (RR = 1.43; 95% CI = 0.92-2.22; P = .11; I = 46%) compared with heparin used in STEMI patients.

CONCLUSION

Bivalirudin associated with lower risk of mortality, major bleeding and thrombocytopenia compared with heparin. However, the use of bivalirudin increase the risk of MI and ST and has similar risk of MACE, TVR and stock compared with heparin used in STEMI patients.

American Society of Hematology 2018 guidelines for management of venous thromboembolism: heparin-induced thrombocytopenia

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction mediated by platelet-activating antibodies that target complexes of platelet factor 4 and heparin. Patients are at markedly increased risk of thromboembolism.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in their decisions about diagnosis and management of HIT.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 33 recommendations. The recommendations address screening of asymptomatic patients for HIT, diagnosis and initial management of patients with suspected HIT, treatment of acute HIT, and special situations in patients with acute HIT or a history of HIT, including cardiovascular surgery, percutaneous cardiovascular intervention, renal replacement therapy, and venous thromboembolism prophylaxis.

CONCLUSIONS

Strong recommendations include use of the 4Ts score rather than a gestalt approach for estimating the pretest probability of HIT and avoidance of HIT laboratory testing and empiric treatment of HIT in patients with a low-probability 4Ts score. Conditional recommendations include the choice among non-heparin anticoagulants (argatroban, bivalirudin, danaparoid, fondaparinux, direct oral anticoagulants) for treatment of acute HIT.

Reduced periprocedural mortality and bleeding rates of radial approach in ST-segment elevation myocardial infarction. Propensity score analysis of data from the ORPKI Polish National Registry

AIMS

We sought to evaluate bleeding complications and periprocedural outcomes of the radial approach (RA) as compared to the femoral approach (FA) during percutaneous coronary intervention (PCI) in "real-world" patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

The study group consisted of 22,812 consecutive patients with STEMI treated with PCI and stent implantation between January 2014 and June 2015 in 151 tertiary invasive cardiology centres in Poland (the ORPKI Polish National Registry). Patients treated using the RA and FA were compared using a propensity score analysis to avoid possible selection bias. The analysis was carried out in an "as-treated" manner. The FA was used in 9,334 (40.9%) and the RA in 13,478 (59.1%) patients. After propensity score matching, a higher total amount of contrast (191.8±8.0 vs. 174.8±68.8 ml; p=0.001) and lower radiation doses (1,279.5±1,346.3 vs. 1,182.6±887 mGy; p=0.02) were reported in FA. More access-site-related bleeding complications after both angiography (0.17% vs. 0.02%; p=0.004) and PCI (0.23% vs. 0.09%; p=0.049) were reported in the FA group. Periprocedural death (1.94% vs. 0.93%; p=0.001) was more common after PCI performed with the FA.

CONCLUSIONS

The radial approach was associated with a lower incidence of periprocedural death in STEMI patients as well as a significant reduction of bleeding complications at the access site.

Safety and Effectiveness of Bivalirudin in Patients Undergoing Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

Recent clinical trials have shown that while bivalirudin exhibits similar efficacy with heparin, it offers several advantages over heparin, such as a better safety profile. We aimed to evaluate the efficacy and safety of bivalirudin use during Percutaneous Coronary Intervention (PCI) in the treatment of angina and acute coronary syndrome (ACS). We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, PubMed, EMBASE, and Science Direct from January 1980 to January 2016. Randomized controlled trials (RCTs) comparing bivalirudin to heparin during the course of PCI in patients with angina or ACS were included. Outcome measures included all-cause mortality, myocardial infarction, revascularisation, stent thrombosis, stroke, and major bleeding. The selection, quality assessment, and data extraction of the included trials were done independently by four authors, and disagreements were resolved by consensus. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated. A total of 12 RCTs involving 44,088 subjects were included. Bivalirudin appeared to be non-superior compared to heparin in reducing all-cause mortality, myocardial infarction, revascularisation, and stroke. Bivalirudin appeared to be related to a higher risk of stent thrombosis when compared to heparin plus provisional use of a glycoprotein IIb/IIIa inhibitor (GPI) at day 30 (RR 1.94 [1.16, 3.24] p < 0.01). Overall, bivalirudin-based regimens present a lesser risk of major bleeding (RR 0.56 [0.44–0.71] p < 0.001), and Thrombolysis In Myocardial Infarction (TIMI) major bleeding (RR 0.56 [0.43–0.73]) compared with heparin-based regimens either with provisional or routine use of a GPI. However, the magnitude of TIMI major bleeding effect varied greatly (p < 0.001), depending on whether a GPI was provisionally used (RR 0.42 [0.34–0.52] p < 0.001) or routinely used (RR 0.60 [0.43 –0.83] p < 0.001), in the heparin arm. This meta-analysis demonstrated that bivalirudin is associated with a lower risk of major bleeding, but a higher risk of stent thrombosis compared to heparin.

Efficacy and safety of bivalirudin versus heparin in patients with diabetes mellitus undergoing percutaneous coronary intervention: A meta-analysis of randomized controlled trials

BACKGROUND

The efficacy and safety of bivalirudin (Biva) versus heparin in patients with diabetes mellitus (DM) who undergo percutaneous coronary intervention (PCI) remain controversial. Our meta-analysis was undertaken to evaluate the efficacy and safety of Biva compared with those of heparin in patients with diabetes undergoing PCI.

METHODS

We searched PubMed, EMBASE, Cochrane Library, and Clinical Trials.gov databases for randomized controlled trials (RCTs). The primary efficacy endpoint was the incidence of major adverse cardiovascular events (MACE), and the primary safety endpoint was the incidence of major bleeding. Secondary efficacy endpoints were incidence of net adverse clinical events (NACE), myocardial infarction (MI), and death. The pooled risk ratio (RR) with the corresponding 95% confidence intervals (CIs) were used to assess the efficacy and safety of Biva versus heparin.

RESULTS

Eleven RCTs met the inclusion criteria, and 8428 patients were included. No significant difference was observed in the subgroup and overall risk of MACE (RR 0.87; 95% CI 0.74-1.02; P = .08; I = 39%) and NACE (RR 0.81; 95% CI 0.61-1.07; P = .14; I = 71%). Biva had an effect similar to that of heparin on the endpoint of death (RR 0.75; 95% CI 0.56-1.02; P = .07; I = 0) and MI (RR 0.92; 95% CI 0.67-1.26; P = .59; I = 0) but decreased the risk of major bleeding (RR 0.63; 95% CI 0.52-0.75; P < .00001; I = 0%).

CONCLUSION

The use of Biva and heparin is associated with a similar risk of MACE, NACE, death, and MI. Biva decreases the risk of major bleeding more significantly than heparin.

Heparin-Induced Thrombocytopenia: A Comprehensive Clinical Review

Heparin-induced thrombocytopenia is a profoundly dangerous, potentially lethal, immunologically mediated adverse drug reaction to unfractionated heparin or, less commonly, to low-molecular weight heparin. In this comprehensive review, the authors highlight heparin-induced thrombocytopenia's risk factors, clinical presentation, pathophysiology, diagnostic principles, and treatment. The authors place special emphasis on the management of patients requiring procedures using cardiopulmonary bypass or interventions in the catheterization laboratory. Clinical vigilance of this disease process is important to ensure its recognition, diagnosis, and treatment. Misdiagnosis of the syndrome, as well as misunderstanding of the disease process, continues to contribute to its morbidity and mortality.

An updated comprehensive meta-analysis of bivalirudin vs heparin use in primary percutaneous coronary intervention

BACKGROUND

Despite several randomized controlled trials and meta-analyses, the ideal anticoagulant for patients undergoing primary percutaneous coronary intervention (PCI) remains controversial. We performed an updated meta-analysis including recently reported randomized clinical trials that compare bivalirudin and heparin with or without provisional administration of a glycoprotein IIb/IIIa inhibitor (GPI) for primary PCI.

METHODS AND RESULTS

Scientific databases and Web sites were searched for randomized clinical trials. Data from 6 trials involving 14,095 patients were included. The pooled risk ratios (RRs) were calculated using random-effects models. Moderator analyses examined the impact of routine use of GPI, radial access, and P2Y12 inhibitors on safety outcomes. At 30 days, patients receiving bivalirudin had rates of major adverse cardiac events similar to those receiving heparin with or without provisional GPI (RR 1.02, 95% CI 0.87-1.19, P = .800), myocardial infarction (RR 1.41, 95% CI 0.94-2.11, P = .089), target vessel revascularization (RR 1.37, 95% CI 0.91-2.04, P = .122), and net adverse clinical events (RR 0.81, 95% CI 0.64-1.01, P = .069). However, bivalirudin use decreased the risk of all-cause mortality (RR 0.81, 95% CI 0.67-0.99, P = .041) and cardiac mortality (RR 0.68, 95% CI 0.51-0.91, P = .009) at 30 days, There were higher rates of acute stent thrombosis (RR 3.31, 95% CI 1.79-6.10, P < .001) in patients receiving bivalirudin. Bivalirudin use also decreased the risk of major bleeding at 30 days by 37% (RR 0.63, 95% CI 0.44-0.90, P = .012), but bleeding risk varied depending on routine GPI use with heparin (RR 0.44, 95% CI 0.23-0.81, P = .009) vs bailout (RR 0.73, 95% CI 0.42-1.25, P = .252), predominantly radial access (RR 0.54, 95% CI 0.25-1.15, P = .114) vs non-radial access (RR 0.60, 95% CI 0.36-0.99, P = .049), and second-generation P2Y12 inhibitor use with bivalirudin (RR 0.70, 95% CI 0.40-1.24, P = .226) vs clopidogrel use (RR 0.39, 95% CI 0.18-0.85, P = .018).

CONCLUSIONS

In primary PCI, relative to heparin, bivalirudin reduces the risk for all-cause mortality, cardiac mortality, and major bleeding but yields similar rates of major adverse cardiac event and net adverse clinical event at 30 days. However, the benefit of a reduction in bleeding with bivalirudin appears to be modulated by the concurrent administration of second-generation P2Y12 inhibitors with bivalirudin, using radial access, and avoiding routine GPI use with heparin.

Short- and long-term outcomes in diabetes patients undergoing percutaneous coronary intervention with bivalirudin compared with heparin and glycoprotein IIb/IIIA inhibitors: A meta-analysis of randomized trials

BACKGROUND

Diabetes patients undergoing percutaneous coronary intervention (PCI) have more complications than nondiabetes patients, including increased long-term mortality. Use of bivalirudin versus heparin and glycoprotein IIb/IIIa inhibitors (GPI) in diabetes patients undergoing PCI and its effect on long-term mortality were evaluated in few randomized trials, but with conflicting results.

METHODS

We searched the literature for randomized controlled trials that compared heparin and GPI therapy with bivalirudin in diabetes patients undergoing PCI. The incidence of major adverse cardiovascular events (MACE), death from any cause, myocardial infarction (MI), urgent revascularization, major and minor bleeding (at 30 days), as well as all-cause mortality at 1 year were included, and meta-analysis was performed.

RESULTS

A total of 5,137 patients with diabetes were included in four randomized trials. At 30 days, bivalirudin, compared with heparin and GPI, caused less major bleeding (odds ratio (OR), 0.68; 95% confidence interval (CI), 0.52-0.89; P = 0.005) and less minor bleeding (OR, 0.48; 95% CI, 0.41-0.57; P < 0.00001) and similar rates of MACE (OR, 0.87; 95% CI, 0.70-1.08; P = 0.21), MI (OR, 0.87; 95% CI, 0.68-1.10; P = 0.25), and urgent revascularization (OR, 1.12; 95% CI, 0.76-1.65; P = 0.57). Death from any cause at 30 day was numerically lower with bivalirudin use but not statistically significant (OR, 0.72; 95% CI, 0.46-1.13; P = 0.15). Mortality at 1 year was significantly lower in diabetes patients treated with bivalirudin compared with heparin and GPI (OR, 0.72; 95% CI, 0.52-0.99; P = 0.04). A secondary analysis suggests that the major bleeding benefit with bivalirudin may be driven by mandated use of GPI in heparin arm.

CONCLUSION

Among patients with diabetes undergoing PCI, bivalirudin caused less major and minor bleeding compared with heparin and GPI, with similar rates of MACE, death, MI, and urgent revascularization at 30 days, but significantly lower mortality rates at 1 year.

Meta-analysis of randomized clinical trials comparing bivalirudin versus heparin plus glycoprotein IIb/IIIa inhibitors in patients undergoing percutaneous coronary intervention and in patients with ST-segment elevation myocardial infarction

This study sought to investigate the relative safety and efficacy of bivalirudin versus heparin plus glycoprotein (GP) IIb/IIIa inhibitors in patients undergoing percutaneous coronary intervention (PCI) and in those with ST-segment elevation myocardial infarction (STEMI). The safety of bivalirudin in PCI, particularly in patients with STEMI, continues to be debated. We searched the on-line databases for randomized controlled trials of bivalirudin versus heparin plus GP IIb/IIIa inhibitors. Data on study design, inclusion and exclusion criteria, sample characteristics, and clinical outcomes at 30 days were extracted. A total of 19,856 PCI patients included in 7 randomized trials and 5,820 patients with STEMI included in 2 randomized trials were separately analyzed. At 30 days, bivalirudin use in patients undergoing PCI resulted in similar rates of death, myocardial infarction, repeat revascularization, and stent thrombosis. In patients with STEMI, bivalirudin use resulted in decreased cardiac mortality (risk ratio [RR] 0.70, 95% confidence interval [CI] 0.50 to 0.97, p=0.03) compared with heparin plus GP IIb/IIIa inhibitors but an increase in definite stent thrombosis at 30 days (RR 1.88, 95% CI 1.09 to 3.24, p=0.02) driven by an increase in acute stent thrombosis (RR 5.48, 95% CI 2.30 to 13.07, p=0.0001). Bivalirudin use was associated with a decrease in Thrombolysis In Myocardial Infarction (TIMI) major (RR 0.58, 95% CI 0.46 to 0.74, p<0.0001) and TIMI minor (RR 0.55, 95% CI 0.48 to 0.63, p<0.0001) bleeding rates in PCI patients as well as in a subgroup of patients with STEMI. In conclusion, in PCI patients anticoagulation with bivalirudin results in similar ischemic adverse events and a reduction in TIMI major and minor bleeding at 30 days compared with heparin plus GP IIb/IIIa inhibitors. In patients with STEMI, bivalirudin use is associated with a reduction in TIMI major and minor bleeding and fewer deaths from cardiac causes but an increase in acute and 30-day definite stent thrombosis.

Balance of Ischemia and Bleeding in Selecting an Antithrombotic Regimen

Complications after percutaneous coronary intervention (PCI) are of 2 types: ischemic and bleeding. This article provides strategies to individualize pharmacologic regimens after PCI based on periprocedural risk assessment. A practical method to assess whether a patient is at risk for ischemic or bleeding complications is the use of risk scores. Patients at a low risk of bleeding benefit from aggressive antithrombotic therapy. Patients at a high risk of bleeding benefit from selective use of antithrombotic agents. As a large number of antithrombotic agents are currently available, individualization of the antithrombotic drug regimes should be considered in every patient.

Antithrombotic therapy in heparin-induced thrombocytopenia: guidelines translated for the clinician

Heparin-induced thrombocytopenia (HIT) is a clinicopathologic syndrome initiated by heparin exposure and characterized by thrombocytopenia and paradoxical thrombophilia. HIT is mediated by the formation of antibodies against the platelet factor 4/heparin complex, which leads to platelet activation, thrombin generation, and potentially fatal thrombotic sequelae. The clinical presentation of HIT is variable and can be easily overlooked. Although a number of functional and antigen-based immunoassays have been developed to detect the presence of HIT antibodies, initial diagnosis is often based on recognition of thrombocytopenia in the appropriate clinical context and later confirmed with immunologic testing. Given the serious clinical consequences of HIT, immediate cessation of heparin products and administration of non-heparin anticoagulants are crucial components of treatment. We provide a review of the clinical syndrome and practical summary of treatment recommendations from the most recent 2012 American College of Chest Physicians evidence-based guidelines for the treatment and prevention of HIT.

Pharmaco-mechanic antithrombotic strategies to reperfusion of the infarct-related artery in patients with ST-elevation acute myocardial infarctions

Primary percutaneous coronary intervention is the best treatment of patients with ST elevation myocardial infarction (STEMI). When managing a STEMI patient, our approach must be rapid and aggresive in order to interrupt the pathological process of thrombus formation and stabilization. The therapy must be initiated prior to angiography (pretreatment), continued during the procedure (periprocedural), recovery phase (in-hospital), and follow-up. The treatment strategies resulting in thrombus dissolution/extraction have focused on optimization of both pharmacological and interventional therapies. At present, there is no optimal evidence-based approach to all patients with STEMI, and the treatment of these patients needs to be modified with respect to the risk profile, availability of medical resources, and our experience. In this review, we summarize current pharmacological and interventional strategies used in the setting of STEMI and discuss potential benefits of novel dosing regimens and combinations of drugs and techniques.

Benefit of bivalirudin versus heparin after transradial and transfemoral percutaneous coronary intervention

Bivalirudin, a direct thrombin inhibitor, has been shown to reduce major bleeding and provide a better safety profile compared to unfractionated heparin (UFH) in patients undergoing percutaneous coronary intervention (PCI) through transfemoral access. Data pertaining to the clinical benefit of bivalirudin compared to UFH monotherapy in patients undergoing transradial PCI are lacking. The present study sought to compare the in-hospital net clinical adverse events, including death, myocardial infarction, target vessel revascularization, and bleeding, for these 2 antithrombotic regimens for all patients at a tertiary care, high-volume radial center. From April 2009 to February 2011, all patients treated with bivalirudin were matched by access site to those receiving UFH. The patients in the bivalirudin group (n = 125) were older (72 ± 13 years vs 66 ± 11 years; p <0.0001), more often had chronic kidney disease (51% vs 30%; p = 0.0012), and more often underwent primary PCI (30% vs 14%, p <0.0037) than the UFH-treated patients (n = 125). A radial approach was used in 71% of both groups. The baseline bleeding risk according to Mehran's score was similar in both groups (14 ± 9 vs 15 ± 8, p = 0.48). In-hospital mortality was 2% in both groups (p = 1.00). No difference in net clinical adverse events or ischemic or bleeding complications was detected between the 2 groups. Bivalirudin reduced both ischemic and bleeding events in femoral-treated patients, but no such clinical benefit was observed in the radial-treated patients. In conclusion, as periprocedural PCI bleeding avoidance strategies have become paramount to optimize the clinical benefit, the interaction between bivalirudin and radial approach deserves additional investigation.

Meta-analysis comparing bivalirudin versus heparin monotherapy on ischemic and bleeding outcomes after percutaneous coronary intervention

With femoral access, bivalirudin decreases risks of major bleeding after percutaneous coronary intervention (PCI) and provides better net clinical benefit compared to unfractionated heparin (UFH) plus planned glycoprotein IIb/IIIa inhibitors. Whether this benefit exists compared to UFH monotherapy is less clear. We performed a systematic review and meta-analysis to compare outcomes in patients undergoing transfemoral PCI with UFH or bivalirudin. Randomized trials (n = 3) and observational studies (n = 13) comparing bivalirudin to UFH monotherapy were reviewed. Primary outcomes were 30-day rates of major adverse cardiovascular events (MACEs) including death, myocardial infarction (MI), urgent revascularization, as well as all-cause mortality, MI, major bleeding, and blood transfusion. We collected data from 16 studies involving 32,492 patients undergoing PCI. Most observational studies were performed in the United States, whereas all randomized trials were done in Europe. Compared to UFH monotherapy, bivalirudin was associated with similar risk of MACEs (odds ratios [OR] 0.92, 95% confidence interval [CI] 0.75 to 1.12), a substantial 45% relative decrease in major bleeding (OR 0.55, 95% CI 0.43 to 0.72), and a trend in the decrease of transfusion (OR 0.87, 95% CI 0.70 to 1.08). A decrease in mortality was seen in observational studies (OR 0.62, 95% CI 0.45 to 0.85) but remained inconclusive in randomized trials (OR 0.63, 95% CI 0.20 to 2.01). MI rate was similar with the 2 anticoagulants. In conclusion, in patients undergoing transfemoral PCI, the benefit of bivalirudin over UFH monotherapy is driven by a significant decrease in major bleeding with similar rates of MACE. As PCI practice moves toward other bleeding-avoidance strategies such as the radial approach, future studies should focus on the interaction between anticoagulant strategy and access-site choice.

Heparin disrupts the CXCR4/SDF-1 axis and impairs the functional capacity of bone marrow-derived mononuclear cells used for cardiovascular repair

RATIONALE

Cell therapy is a promising option for the treatment of acute or chronic myocardial ischemia. The intracoronary infusion of cells imposes the potential risk of cell clotting, which may be prevented by the addition of anticoagulants. However, a comprehensive analysis of the effects of anticoagulants on the function of the cells is missing.

OBJECTIVE

Here, we investigated the effects of heparin and the thrombin inhibitor bivalirudin on bone marrow-derived mononuclear cell (BMC) functional activity and homing capacity.

METHODS AND RESULTS

Heparin, but not bivalirudin profoundly and dose-dependently inhibited basal and stromal cell-derived factor 1 (SDF-1)-induced BMC migration. Incubation of BMCs with 20 U/mL heparin for 30 minutes abrogated SDF-1-induced BMC invasion (16±8% of control; P<0.01), whereas no effects on apoptosis or colony formation were observed (80±33% and 100±44% of control, respectively). Pretreatment of BMCs with heparin significantly reduced the homing of the injected cells in a mouse ear-wound model (69±10% of control; P<0.05). In contrast, bivalirudin did not inhibit in vivo homing of BMCs. Mechanistically, heparin binds to both, the chemoattractant SDF-1 and its receptor, chemokine receptor 4 (CXCR4), blocking CXCR4 internalization as well as SDF-1/CXCR4 signaling after SDF-1 stimulation.

CONCLUSIONS

Heparin blocks SDF-1/CXCR4 signaling by binding to the ligand as well as the receptor, thereby interfering with migration and homing of BMCs. In contrast, the thrombin inhibitor bivalirudin did not interfere with BMC homing or SDF-1/CXCR4 signaling. These findings suggest that bivalirudin but not heparin might be recommended as an anticoagulant for intracoronary infusion of BMCs for cell therapy after cardiac ischemia.

Direct thrombin inhibitors in cardiovascular disease

Limitations of commonly used anticoagulants, unfractionated heparin, low-molecular-weight heparin, and oral vitamin K antagonists have prompted the development of alternative therapies. Direct thrombin inhibitors are a new class of anticoagulants that bind directly to thrombin and inhibit its interaction with substrates. In this Review, we critically examine the evidence from randomized controlled trials for the efficacy and safety of the parenteral direct thrombin inhibitors bivalirudin and argatroban, and the novel oral direct thrombin inhibitor dabigatran etexilate, in cardiovascular and thrombotic disease.

Treatment and prevention of heparin-induced thrombocytopenia: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is an antibody-mediated adverse drug reaction that can lead to devastating thromboembolic complications, including pulmonary embolism, ischemic limb necrosis necessitating limb amputation, acute myocardial infarction, and stroke.

METHODS

The methods of this guideline follow the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

Among the key recommendations for this article are the following: For patients receiving heparin in whom clinicians consider the risk of HIT to be > 1%, we suggest that platelet count monitoring be performed every 2 or 3 days from day 4 to day 14 (or until heparin is stopped, whichever occurs first) (Grade 2C). For patients receiving heparin in whom clinicians consider the risk of HIT to be < 1%, we suggest that platelet counts not be monitored (Grade 2C). In patients with HIT with thrombosis (HITT) or isolated HIT who have normal renal function, we suggest the use of argatroban or lepirudin or danaparoid over other nonheparin anticoagulants (Grade 2C). In patients with HITT and renal insufficiency, we suggest the use of argatroban over other nonheparin anticoagulants (Grade 2C). In patients with acute HIT or subacute HIT who require urgent cardiac surgery, we suggest the use of bivalirudin over other nonheparin anticoagulants or heparin plus antiplatelet agents (Grade 2C).

CONCLUSIONS

Further studies evaluating the role of fondaparinux and the new oral anticoagulants in the treatment of HIT are needed.