Bivalirudin versus unfractionated heparin: a meta-analysis of patients receiving percutaneous coronary intervention for acute coronary syndromes

Being precise with anticoagulation to reduce adverse drug reactions: are we there yet?

Anticoagulants are potent therapeutics widely used in medical and surgical settings, and the amount spent on anticoagulation is rising. Although warfarin remains a widely prescribed oral anticoagulant, prescriptions of direct oral anticoagulants (DOACs) have increased rapidly. Heparin-based parenteral anticoagulants include both unfractionated and low molecular weight heparins (LMWHs). In clinical practice, anticoagulants are generally well tolerated, although interindividual variability in response is apparent. This variability in anticoagulant response can lead to serious incident thrombosis, haemorrhage and off-target adverse reactions such as heparin-induced thrombocytopaenia (HIT). This review seeks to highlight the genetic, environmental and clinical factors associated with variability in anticoagulant response, and review the current evidence base for tailoring the drug, dose, and/or monitoring decisions to identified patient subgroups to improve anticoagulant safety. Areas that would benefit from further research are also identified. Validated variants in VKORC1, CYP2C9 and CYP4F2 constitute biomarkers for differential warfarin response and genotype-informed warfarin dosing has been shown to reduce adverse clinical events. Polymorphisms in CES1 appear relevant to dabigatran exposure but the genetic studies focusing on clinical outcomes such as bleeding are sparse. The influence of body weight on LMWH response merits further attention, as does the relationship between anti-Xa levels and clinical outcomes. Ultimately, safe and effective anticoagulation requires both a deeper parsing of factors contributing to variable response, and further prospective studies to determine optimal therapeutic strategies in identified higher risk subgroups.

Bivalirudin Versus Heparin During PCI in NSTEMI: Individual Patient Data Meta-Analysis of Large Randomized Trials

BACKGROUND

The benefit:risk profile of bivalirudin versus heparin anticoagulation in patients with non-ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) is uncertain. Study-level meta-analyses lack granularity to provide conclusive answers. We sought to compare the outcomes of bivalirudin and heparin in patients with non-ST-segment-elevation myocardial infarction undergoing PCI.

METHODS

We performed an individual patient data meta-analysis of patients with non-ST-segment-elevation myocardial infarction in all 5 trials that randomized ≥1000 patients with any myocardial infarction undergoing PCI to bivalirudin versus heparin (MATRIX [Minimizing Adverse Hemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox], VALIDATE-SWEDEHEART [Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy in the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry Trial], ISAR-REACT 4 [Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 4], ACUITY [Acute Catheterization and Urgent Intervention Triage Strategy], and BRIGHT [Bivalirudin in Acute Myocardial Infarction vs Heparin and GPI Plus Heparin Trial]). The primary effectiveness and safety end points were 30-day all-cause mortality and serious bleeding.

RESULTS

A total of 12 155 patients were randomized: 6040 to bivalirudin (52.3% with a post-PCI bivalirudin infusion), and 6115 to heparin (53.2% with planned glycoprotein IIb/IIIa inhibitor use). Thirty-day mortality was not significantly different between bivalirudin and heparin (1.2% versus 1.1%; adjusted odds ratio, 1.24 [95% CI, 0.86-1.79]; P=0.25). Cardiac mortality, reinfarction, and stent thrombosis rates were also not significantly different. Bivalirudin reduced serious bleeding (both access site-related and non-access site-related) compared with heparin (3.3% versus 5.5%; adjusted odds ratio, 0.59; 95% CI, 0.48-0.72; P<0.0001). Outcomes were consistent regardless of use of a post-PCI bivalirudin infusion or routine lycoprotein IIb/IIIa inhibitor use with heparin and during 1-year follow-up.

CONCLUSIONS

In patients with non-ST-segment-elevation myocardial infarction undergoing PCI, procedural anticoagulation with bivalirudin and heparin did not result in significantly different rates of mortality or ischemic events, including stent thrombosis and reinfarction. Bivalirudin reduced serious bleeding compared with heparin arising both from the access site and nonaccess sites.

Inhibitory role of recombinant neorudin on canine coronary artery thrombosis

The anticoagulant application is an effective treatment modality for cardiovascular diseases such as coronary heart disease, unstable angina pectoris, and myocardial infarction. In this study, the antithrombotic effect of recombinant neorudin (EPR‐hirudin, EH) was evaluated using a canine model of coronary artery thrombosis. A canine model with platelet thrombosis in the left circumferent branch of the coronary artery was designed using Folt's method, and the anti‐thrombus activity of EH was investigated. Femoral administration of EH intravenously had a significant dose‐dependent inhibitory effect on canine coronary artery thrombosis and the effective rates were 66.7% (p < .05), 83.3% (p < .05), and 100% (p < .01) after injection of 0.3, 1.0, and 3.0 mg/kg EH, respectively. Furthermore, EH demonstrated lower bleeding, with shorter bleeding time and less bleeding loss than low molecular weight heparin (LMWH). Under the similar effect intensity of EH and LMWH (85 IU/kg), the bleeding time of the EH group at 30 min was shorter, and the blood loss at 30–120 min was less than that of LMWH (p < .05 and p < .05–.001, respectively). EH had a significant dose‐dependent inhibitory effect in the dose range of 0.3–3.0 mg/kg on the coronary artery thrombosis and lower bleeding side effects than LMWH with a similar antithrombosis effect.

Evidence in Guidelines for Treatment of Coronary Artery Disease

In this chapter, we focus on evidences in current guidelines for treatment of coronary artery disease (CAD). In Part 1, diet and lifestyle management is discussed, which plays an important role in CAD risk control, including forming healthy dietary pattern, maintaining proper body weight, physical exercise, smoking cessation, and so on. Part 2 elaborated on revascularization strategies and medical treatments in patients presenting with acute coronary syndrome (ACS), including specific AHA and ESC guidelines on ST elevation myocardial infarction (STEMI) and non-ST elevation ACS (NSTE-ACS). Part 3 discussed chronic stable coronary artery disease (SCAD), the treatment objective of which is a combination of both symptomatic and prognostic improvement. Yet many of the recommendations for SCAD are expert-based rather than evidence-based. Initial medical treatment is safe and beneficial for most patients. While cumulating studies have focused on optimizing pharmacological therapy (referring to nitrates, beta-blockers, calcium channel blockers, antiplatelet agents, ACEI/ARB, statins, etc.), education, habitual modification, and social support matters a lot for reducing cardiac morbidity and mortality. Patients with moderate-to-severe symptoms and complex lesions should be considered for revascularization. But practical management of revascularization shall take individual characteristics, preference, and compliance into consideration as well.

The impact of unfractionated heparin or bivalirudin on patients with stable coronary artery disease undergoing percutaneous coronary intervention

OBJECTIVES

To compare bleeding and clinical events of patients with stable angina or silent ischemia undergoing percutaneous coronary intervention (PCI) treated with unfractionated heparin (UFH) or bivalirudin.

BACKGROUND

Few direct comparisons between UFH monotherapy versus bivalirudin exist for patients with stable ischemic heart disease undergoing PCI.

METHODS

A prospective, investigator-initiated, single-center, single-blinded, randomized trial of UFH versus bivalirudin was conducted. The primary endpoint was all bleeding (major and minor) from index-hospitalization to 30 days post discharge. Secondary endpoints included major adverse cerebral and cardiovascular events (MACCE) and net adverse clinical events (NACE).

RESULTS

Two-hundred-sixty patients were randomized for treatment with either UFH (n = 123) (47%) or bivalirudin (n = 137) (53%) There were no significant differences in baseline clinical and angiographic characteristics between the two groups. Primary endpoint was similar in both groups (10.9% with bivalirudin vs 7.3% with UFH [P = 0.31]). Major bleeding rates were 5.8% and 2.4%, respectively (P = 0.17). There was a higher MACCE (3.5% vs 0%, P = 0.03) and NACE (8.8% vs 2.4%, P = 0.03) rate with bivalirudin compared to UFH, respectively. Bivalirudin had increased odds of NACE (OR = 3.65, 95% CI: 1.00-13.3.6). Death and stent thrombosis rates were low and similar in both groups. Radial access was associated with fewer bleeding events compared to femoral access but not statistically significant (P = 0.29).

CONCLUSIONS

Among patients with stable angina or silent ischemia, there was no difference between UFH and bivalirudin in bleeding rates up to 30-days post-PCI. MACCE and NACE were higher among the bivalirudin group. Radial access was associated with a numerically lower rate of bleeding compared with femoral access.

Bivalirudin versus heparin, without glycoprotein inhibition, in percutaneous coronary intervention: A comparison of ischemic and hemorrhagic outcomes over 10years

OBJECTIVE

The choice of antithrombotic agent used during percutaneous coronary intervention (PCI) is controversial. While earlier studies suggested a reduction in bleeding events with bivalirudin, these studies were confounded by the concomitant use of glycoprotein IIbIIIa inhibitors (GPI) in the heparin group. More recent studies have challenged the superiority of bivalirudin, pointing to an increased risk of stent thrombosis. Real-world data remains limited.

METHODS

We queried our institutional catheterization laboratory database for all PCI cases performed between January 2003 and December 2012 using only heparin or only bivalirudin (no use of GPI). We collected data on relevant patient and procedural characteristics and compared both efficacy and safety outcomes. We adjusted for baseline differences using coarsened exacting matching.

RESULTS

8061 cases met our inclusion criteria. Of these, 34.9% were performed with heparin alone and 65.1% with bivalirudin. After adjusting for baseline differences, we found that those patients receiving heparin had a slightly lower risk of post-procedural abrupt vessel closure (0.1% vs 0.5%). All other outcomes favored bivalirudin including procedural success (97.2% vs 95.5%), transfusion within 72h (2.2% vs 4.8%), retroperitoneal bleeding (0.1% vs 0.8%), and all-cause mortality (0.9% vs 1.9%). Subgroup analysis suggested that outcomes were different only in non-elective cases and non STEMI cases.

CONCLUSION

Heparin appears to offer the advantage of slightly reduced risk of abrupt vessel closure post-procedure but at the cost of increased hemorrhagic complications and all-cause mortality. This difference in outcomes may be limited to non-elective and non STEMI cases with femoral access.

Intracoronary Bivalirudin Bolus in ST-Elevation Myocardial Infarction Patients Treated with Primary Angioplasty: Theoretical Bases, Clinical Experience, and Future Applications

Intracoronary thrombus is a common finding in acute coronary syndromes and often correlates with adverse prognosis and complications during percutaneous coronary interventions (PCIs). Bivalirudin, a direct thrombin inhibitor, is one of the recommended antithrombotic treatments for PCI in ST-elevation myocardial infarction (STEMI). The intracoronary administration of a bivalirudin loading dose, even if off-label, offers theoretical advantages over the standard intravenous route, providing a very high drug concentration in the infarct-related artery without increasing the total dose of the drug administered. After the description in case reports of such an approach, a larger scale experience was recently reported in a large cohort of patients with STEMI treated during primary PCI with a bivalirudin intracoronary loading dose followed by the standard intravenous maintenance infusion. As a control group, a propensity score-matched cohort of patients undergoing primary PCI treated with intravenous bivalirudin in the same institution was selected. Compared with the intravenous bolus, the intracoronary administration of bivalirudin was associated with improved ST-segment resolution, lower post-procedural peak CK-MB levels, and better Thrombolysis in Myocardial Infarction (TIMI) frame count values, without difference in bleeding rates. Thus, this new promising antithrombotic strategy, based on the intracoronary administration of a bivalirudin loading dose during primary PCI, appeared safe, improved myocardial reperfusion, and mitigated enzymatic myocardial infarct size compared with the standard intravenous protocol. Randomized trials are warranted to confirm these results and evaluate the possible long-term clinical benefits.

New Approaches to the Role of Thrombin in Acute Coronary Syndromes: Quo Vadis Bivalirudin, a Direct Thrombin Inhibitor?

The pathophysiology of acute coronary syndrome (ACS) involves platelet activation and thrombus formation after the rupture of atherosclerotic plaques. Thrombin is generated at the blood-plaque interface in association with cellular membranes on cells and platelets. Thrombin also amplifies the response to the tissue injury, coagulation and platelet response, so the treatment of ACS is based on the combined use of both antiplatelet (such as aspirin, clopidogrel, prasugrel and ticagrelor) and antithrombotic drugs (unfractionated heparin, enoxaparin, fondaparinux and bivalirudin). Bivalirudin competitively inhibits thrombin with high affinity, a predictable response from its linear pharmacokinetics and short action. However, a present remarkable controversy exists between the latest main Guidelines in Clinical Practice and the key trials evaluating the use of bivalirudin in ACS. The aim of this review is to update the development of bivalirudin, including pharmacological properties, obtained information from clinical trials evaluating efficacy and safety of bivalirudin in ACS; as well as the recommendations of clinical Guidelines.