A direct comparison of intravenous enoxaparin with unfractionated heparin in primary percutaneous coronary intervention (from the ATOLL trial)

Postprocedural Anticoagulation After Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction: A Multicenter, Randomized, Double-Blind Trial

BACKGROUND

Postprocedural anticoagulation (PPA) is frequently administered after primary percutaneous coronary intervention in ST-segment-elevation myocardial infarction, although no conclusive data support this practice.

METHODS

The RIGHT trial (Comparison of Anticoagulation Prolongation vs no Anticoagulation in STEMI Patients After Primary PCI) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled, superiority trial conducted at 53 centers in China. Patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention were randomly assigned by center to receive low-dose PPA or matching placebo for at least 48 hours. Before trial initiation, each center selected 1 of 3 PPA regimens (40 mg of enoxaparin once daily subcutaneously; 10 U·kg·h of unfractionated heparin intravenously, adjusted to maintain activated clotting time between 150 and 220 seconds; or 0.2 mg·kg·h of bivalirudin intravenously). The primary efficacy objective was to demonstrate superiority of PPA to reduce the primary efficacy end point of all-cause death, nonfatal myocardial infarction, nonfatal stroke, stent thrombosis (definite), or urgent revascularization (any vessel) within 30 days. The key secondary objective was to evaluate the effect of each specific anticoagulation regimen (enoxaparin, unfractionated heparin, or bivalirudin) on the primary efficacy end point. The primary safety end point was Bleeding Academic Research Consortium 3 to 5 bleeding at 30 days.

RESULTS

Between January 10, 2019, and September 18, 2021, a total of 2989 patients were randomized. The primary efficacy end point occurred in 37 patients (2.5%) in both the PPA and placebo groups (hazard ratio, 1.00 [95% CI, 0.63 to 1.57]). The incidence of Bleeding Academic Research Consortium 3 to 5 bleeding did not differ between the PPA and placebo groups (8 [0.5%] vs 11 [0.7%] patients; hazard ratio, 0.74 [95% CI, 0.30 to 1.83]).

CONCLUSIONS

Routine PPA after primary percutaneous coronary intervention was safe but did not reduce 30-day ischemic events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03664180.

In vitro evaluation of anticoagulant therapy management when urgent percutaneous coronary intervention is required in rivaroxaban-treated patients

We investigated in vitro the management of intraprocedural anticoagulation in patients requiring immediate percutaneous coronary intervention (PCI) while using regular direct oral anticoagulants (DOACs). Twenty-five patients taking 20 mg of rivaroxaban once daily comprised the study group, while five healthy volunteers included the control group. In the study group, a beginning (24 h after the last rivaroxaban dose) examination was performed. Then, the effects of basal and four different anticoagulant doses (50 IU/kg unfractionated heparin (UFH), 100 IU/kg UFH, 0.5 mg/kg enoxaparin, and 1 mg/kg enoxaparin) on coagulation parameters were investigated at the 4th and 12th h following rivaroxaban intake. The effects of four different anticoagulant doses were evaluated in the control group. The anticoagulant activity was assessed mainly by anti-factor Xa (anti-Xa) levels. Beginning anti-Xa levels were significantly higher in the study group than in the control group (0.69 ± 0.77 IU/mL vs. 0.20 ± 0.14 IU/mL; p < 0.05). The study group's 4th and 12th-h anti-Xa levels were significantly higher than the beginning level (1.96 ± 1.35 IU/mL vs. 0.69 ± 0.77 IU/mL; p < 0.001 and 0.94 ± 1.21 IU/mL vs. 0.69 ± 0.77 IU/mL; p < 0.05, respectively). Anti-Xa levels increased significantly in the study group with the addition of UFH and enoxaparin doses at the 4th and 12th h than the beginning (p < 0.001 at all doses). The safest anti-Xa level (from 0.94 ± 1.21 to 2.00 ± 1.02 IU/mL) was achieved 12 h after rivaroxaban with 0.5 mg/kg enoxaparin. Anticoagulant activity was sufficient for urgent PCI at the 4th h after rivaroxaban treatment, and additional anticoagulant administration may not be required at this time. Twelve hours after taking rivaroxaban, administering 0.5 mg/kg of enoxaparin may provide adequate and safe anticoagulant activity for immediate PCI. This experimental study result should confirm with clinical trials (NCT05541757).

Factors associated with bleeding events from enoxaparin used for patients with acute coronary syndrome

BACKGROUND

Low molecular weight heparins (LMWHs) are the mainstay of treatment for acute coronary syndrome (ACS). However, bleeding, the main side effect, is associated with prolonged hospitalization and mortality. Therefore, assessment of the incidence of bleeding and associated risk factors is crucial in developing an appropriate treatment plan to prevent bleeding.

METHODS

A retrospective cohort study was conducted in patients with ACS admitted to a university hospital in Bangkok, Thailand between 2011 and 2015 and received enoxaparin. To estimate the incidence of bleeding events, patients were followed up for 30 days from the first enoxaparin dose. Multiple logistic regression was used to determine factors associated with bleeding events.

RESULTS

From a total of 602 patients, the incidence of bleeding was 15.8%, of which 5.7% involved major bleeding. The risk factors for any form of bleeding were aged at least 65 years (odds ratio [OR], 1.99; 95% confidence interval [CI], 1.18 to 3.36), history of bleeding (OR, 3.79; 95% CI, 1.24 to 11.55), and history of oral anticoagulant exposure (OR, 4.73; 95% CI, 1.74 to 12.86).

CONCLUSION

ACS patients treated with enoxaparin had an increased risk of bleeding if they were aged 65 years or older, had a history of bleeding events, and had a history of taking oral anticoagulants.

Antithrombotic Treatment in Coronary Artery Disease

Coronary artery disease exhibits growing mortality and morbidity worldwide despite the advances in pharmacotherapy and coronary intervention. Coronary artery disease is classified in the acute coronary syndromes and chronic coronary syndromes according to the most recent guidelines of the European Society of Cardiology. Antithrombotic treatment is the cornerstone of therapy in coronary artery disease due to the involvement of atherothrombosis in the pathophysiology of the disease. Administration of antiplatelet agents, anticoagulants and fibrinolytics reduce ischemic risk, which is amplified early post-acute coronary syndromes or post percutaneous coronary intervention; though, antithrombotic treatment increases the risk for bleeding. The balance between ischemic and bleeding risk is difficult to achieve and is affected by patient characteristics, procedural parameters, concomitant medications and pharmacologic characteristics of the antithrombotic agents. Several pharmacological strategies have been evaluated in patients with coronary artery disease, such as the effectiveness and safety of antithrombotic agents, optimal dual antiplatelet treatment schemes and duration, aspirin de-escalation strategies of dual antiplatelet regimens, dual inhibition pathway strategies as well as triple antithrombotic therapy. Future studies are needed in order to investigate the gaps in our knowledge, including special populations.

The Evolution of Anticoagulation for Percutaneous Coronary Intervention: A 40-Year Journey

The selection of antithrombotic strategies continue to be of utmost importance during percutaneous coronary intervention (PCI) and have evolved over the past 40 years. Although the backbone of therapy during PCI continues to be a combination of oral antiplatelets and parenteral anticoagulants, a variety of different approaches have been tested over time. In particular, different choices of anticoagulation management have been tested in the stable ischemic heart disease and acute coronary syndrome setting. Evaluation of alternative regimens in the quest to balance ischemic and bleeding risk have undoubtedly improved patient care with PCI. In the current review we highlight the evolution of evidence-based therapeutic options over the past 40 years from the beginning of coronary angioplasty to contemporary PCI. We provide insight into future therapeutic options and provide a contemporary overview of anticoagulation choices for patients who require PCI on the basis of up-to-date evidence balancing ischemic and bleeding risk and according to clinical presentation.

Glycoprotein IIb/IIIa inhibitors use in the setting of primary percutaneous coronary intervention for ST elevation myocardial infarction in patients pre-treated with newer P2Y12 inhibitors

OBJECTIVES

We sought to investigate the safety and potential benefit of administrating glycoprotein IIb-IIIa inhibitors (GPIs) on top of more potent P2Y12 inhibitors.

BACKGROUND

A number of clinical trials, performed at a time when pretreatment and potent platelet inhibition was not part of routine clinical practice, have documented clinical benefits of GPI in ST-segment elevation myocardial infarction (STEMI) patients at the cost of a higher risk of bleeding.

METHODS

We used the data of a prospective, ongoing registry of patients admitted for STEMI in our center. For the purpose of this study only patients presenting for primary percutaneous coronary intervention and pretreated with new P2Y12 inhibitors (prasugrel or ticagrelor) were included. We compared patients who received GPI with those who did not.

RESULTS

Eight hundred twenty-four STEMI patients were included in our registry; GPIs were used in 338 patients (41%). GPI patients presented more often with cardiogenic shock and Thrombolysis in myocardial infarction (TIMI) flow grade <3. GPI use was not associated with an increase in in-hospital or 3-month mortality. Bleeding endpoints were similar in both groups.

CONCLUSIONS

Our study suggests that GPI may be used safely in combination with recent P2Y12 inhibitors in STEMI patients in association with modern primary percutaneous coronary intervention strategies (radial access and anticoagulation with enoxaparin) with similar bleeding and mortality rates at hospital discharge and 3-month follow-up.

Antithrombotic treatment in primary percutaneous coronary intervention

INTRODUCTION

Despite a timely mechanical reperfusion with primary percutaneous coronary intervention (pPCI) patients presenting with ST-elevation myocardial infarction (STEMI) display an increased risk of adverse cardiovascular events. Several studies have demonstrated that guideline-directed antithrombotic therapy is effective to reduce this risk. However, there is still much to be accomplished to improve antithrombotic therapies in this clinical setting.

AREAS COVERED

This paper reviews current data on antithrombotic therapy in STEMI patients undergoing pPCI.

EXPERT OPINION

Antithrombotic therapy for STEMI patients undergoing pPCI should take into account the variability of thrombotic and bleeding risk in the short and long term. Patients with STEMI profit from the administration of early onset antiplatelet agents and anticoagulation to achieve sufficient and predictable antithrombotic effect at the time of pPCI. Thereafter, antithrombotic therapies should be tailored to individual risk of recurrence over the long term, to avoid excess bleeding, while ensuring adequate secondary ischemic prevention.

Antithrombotic Therapy in Acute Coronary Syndromes: Current Evidence and Ongoing Issues Regarding Early and Late Management

A few decades ago, the understanding of the pathophysiological processes involved in the coronary artery thrombus formation has placed anticoagulant and antiplatelet agents at the core of the management of acute coronary syndrome (ACS). Increasingly potent antithrombotic agents have since been evaluated, in various association, timing, or dosage, in numerous randomized controlled trials to interrupt the initial thrombus formation, prevent ischemic complications, and ultimately improve survival. Primary percutaneous coronary intervention, initial parenteral anticoagulation, and dual antiplatelet therapy with potent P2Y₁₂ inhibitors have become the hallmark of ACS management revolutionizing its prognosis. Despite these many improvements, much more remains to be done to optimize the onset of action of the various antithrombotic therapies, for further treating and preventing thrombotic events without exposing the patients to an unbearable hemorrhagic risk. The availability of various potent P2Y₁₂ inhibitors has opened the door for individualized therapeutic strategies based on the clinical setting as well as the ischemic and bleeding risk of the patients, while the added value of aspirin has been recently challenged. The strategy of dual-pathway inhibition with P2Y₁₂ inhibitors and low-dose non-vitamin K antagonist oral anticoagulant has brought promising results for the early and late management of patients presenting with ACS with and without indication for oral anticoagulation. In this updated review, we aimed at describing the evidence supporting the current gold standard of antithrombotic management of ACS. More importantly, we provide an overview of some of the ongoing issues and promising therapeutic strategies of this ever-evolving topic.

Comparative Effectiveness and Costs of Enoxaparin Monotherapy Versus Unfractionated Heparin Monotherapy in Treating Acute Coronary Syndrome

BACKGROUND

Enoxaparin and unfractionated heparin (UFH) are guideline-recommended anticoagulants for patients with acute coronary syndrome (ACS), including unstable angina (UA) and myocardial infarction with (STEMI) or without ST-segment elevation (NSTEMI). Prior efficacy and safety evidence are mainly from clinical trials. Economic data are insufficient. This study examined the differences in utilization, effectiveness, safety, and costs in treating ACS between enoxaparin and UFH monotherapy using real-world data.

METHODS

Using data from 859 US hospitals, inpatients ≥ 18 years of age with a diagnosis of an initial episode of ACS between 2010 and 2016 were identified. Outcomes included 30-day risk of non-fatal myocardial infarction (MI), recurrent angina, in-hospital mortality, composite ischemic complication (having MI/recurrent angina/death), major bleeding, and costs. Multivariable regression was used to compare outcomes between enoxaparin and UFH monotherapy.

RESULTS

Among 1,048,053 eligible patients (UA: 219,259; NSTEMI: 582,134; STEMI: 246,660), the prevalence of enoxaparin monotherapy was 12.0%, 13.9%, and 5.1%, and the prevalence of UFH monotherapy was 45.1%, 43.1% and 59.8%, for UA, NSTEMI, and STEMI patients, respectively. Enoxaparin was associated with a lower risk of ischemic complications and death among NSTEMI, but not in UA or STEMI patients, and with a lower risk of major bleeding in all patients. Cost savings per patient during index admission and 30-day follow-up for enoxaparin over UFH was $2972 for UA, $2475 for NSTEMI, and $3050 for STEMI.

CONCLUSIONS

Enoxaparin was associated with a lower risk of ischemic complications (including death), lower costs, and better safety than UFH among NSTEMI patients. Improving upstream selection of anticoagulants in appropriate populations may help optimize clinical outcomes and costs.

Comparison of Safety between Different Kinds of Heparins in Patients Receiving Intra-Aortic Balloon Counterpulsation

Background  The present study aimed to compare the effectiveness and safety of low molecular-weight-heparin (LMWH) and unfractionated heparin (UFH) in acute myocardial infarction (AMI) patients receiving intra-aortic balloon counterpulsation (IABP).

Materials and Methods  We retrospectively analyzed a total of 344 patients receiving IABP for cardiogenic shock, severe heart failure, ventricular septal rupture, or mitral valve prolapse due to AMI. A total of 161 patients received UFH (a bolus injection 70 U/kg immediately after IABP, followed by infusion at a rate of 15 U/kg/hour and titration to for 50 to 70 seconds of activated partial thromboplastin time. A total of 183 patients received LMWH (subcutaneous injection of 1.0 mg/kg every 12 hours for 5 to 7 days and 1.0 mg/kg every 24 hours thereafter). Events of ischemia, arterial thrombosis or embolism, and bleeding during IABP were evaluated. Major bleeding was defined as a hemoglobin decrease by >50 g/L (vs. prior to IABP) or bleeding that caused hemodynamic shock or life-threatening or requiring blood transfusion.

Results  Subjects receiving UFH and LMWH did not differ in baseline characteristics. Ischemia was noted in five (3.1%) and two (1.1%) subjects in UFH and LMWH groups, respectively. Arterial thromboembolism occurred in three (1.9%) subjects in the UFH group, but not in the LMWH group. Logistic regression analysis failed to reveal an association between ischemia or bleeding with heparin type. Major bleeding occurred in 16 (9.9%) and six (3.3%) patients in the UFH and LWMH groups, respectively ( p  = 0.014). Regression analysis indicated that LMWH is associated with less major bleeding.

Conclusion  LMWH could reduce the risk of major bleeding in patients receiving IABP. Whether LMWH could reduce arterial thromboembolism needs further investigation.

2019 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Guidelines on the Acute Management of ST-Elevation Myocardial Infarction: Focused Update on Regionalization and Reperfusion

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients.

Biomarkers of Thrombosis in ST-Segment Elevation Myocardial Infarction: A Substudy of the ATOLL Trial Comparing Enoxaparin Versus Unfractionated Heparin

BACKGROUND

The aim was to compare the peri-procedural biomarkers of coagulation and platelet activation in patients randomly allocated to intravenous enoxaparin or unfractionated heparin (UFH) in the ATOLL randomized trial (NCT00718471).

METHODS AND RESULTS

A total of 129 patients (n = 58 enoxaparin and n = 71 UFH) admitted for ST-segment elevation myocardial infarction (STEMI) treated by percutaneous coronary intervention (PCI) were included in this substudy of the ATOLL trial. Activated partial thromboplastin time ratio, anti-Xa activity, von Willebrand factor antigen, prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complex (TAT), tissue factor pathway inhibitor and soluble CD40 ligand were measured at sheath insertion (T1) and at the end of the PCI (T2) and correlated with 1-month clinical outcomes. Target anticoagulation levels at T2 were more readily achieved in patients receiving enoxaparin compared to those receiving UFH (80.3 vs 18.2%, p < 0.0001). Increased levels of F1 + 2 and TAT measured at T2 were associated with the incidence of the composite ischemic endpoint (p = 0.04 and p = 0.03) and all-cause mortality (p < 0.0001 and p = 0.002). Release of F1 + 2 between T1 and T2 also predicted the composite ischemic endpoint (312 ± 513 vs 37 ± 292, p = 0.04) and net clinical outcome (185 ± 405 vs 3.2 ± 278, p = 0.03).

CONCLUSIONS

During primary PCI, enoxaparin achieved therapeutic levels more frequently than UFH. Higher level of thrombin generation measured at the end of the PCI procedure was associated with more frequent ischemic events.

What is new in the 2017 ESC clinical practice guidelines

Guidelines and recommendations are designed to guide physicians in making decisions in daily practice. Guidelines provide a condensed summary of all available evidence at the time of the writing process. Recommendations take into account the risk-benefit ratio of particular diagnostic or therapeutic means and the impact on outcome, but not monetary or political considerations. Guidelines are not substitutes but are complementary to textbooks and cover the European Society of Cardiology (ESC) core curriculum topics. The level of evidence and the strength of recommendations of particular treatment options were recently newly weighted and graded according to predefined scales. Guidelines endorsement and implementation strategies are based on abridged pocket guidelines versions, electronic version for digital applications, translations into the national languages or extracts with reference to main changes since the last version. The present article represents a condensed summary of new and practically relevant items contained in the 2017 European Society of Cardiology (ESC) guidelines for the management of acute myocardial infarction in patients with ST-segment elevation, with reference to key citations.

Low-Dose Unfractionated Heparin with Sequential Enoxaparin in Patients with Diabetes Mellitus and Complex Coronary Artery Disease during Elective Percutaneous Coronary Intervention

Background:

Despite its limitations, unfractionated heparin (UFH) has been the standard anticoagulant used during percutaneous coronary intervention (PCI). This study compared the safety of low-dose UFH with sequential enoxaparin with that of UFH in patients with diabetes mellitus (DM) and complex coronary artery disease receiving elective PCI.

Methods:

In this retrospective study, 514 consecutive patients with atherosclerotic cardiovascular diseases and type 2 DM were admitted to the hospital and received selective PCI, from January 2013 to December 2015. All patients with PCI received low-dose UFH with enoxaparin (intraductal 50 U/kg UFH and 0.75 mg/kg enoxaparin, n = 254; UFH-Enox group) or UFH only (intraductal 100 U/kg UFH, n = 260; UFH group). The study endpoints were major adverse cardiac events (MACEs), namely death, myocardial infarction (MI), stroke, target-vessel immediate revascularization (TVR), and thrombolysis in MI (TIMI) major bleeding, within 30 days and 1 year after PCI. Any catheter thrombosis during the procedure was recorded.

Results:

Only one patient had an intraductal thrombus in the UFH group. At the 30-day follow-up, no MACE occurred in any group; seven and five cases of recurrent angina and/or rehospitalization were reported in the UFH-Enox and UFH groups, respectively; there was no significant difference between the two groups (χ² = 0.11, P = 0.77). There was no TIMI major bleeding in the groups. With respect to the 1-year endpoint, two cases of recurrent MI and two of TVRs were reported in the UFH-Enox group, whereas in the UFH group, one case of recurrent MI and three of TVRs were reported; no significant difference existed between the two groups (χ² = 0, P = 0.99). There were 30 and 25 recurrent angina and/or rehospitalizations in the UFH-Enox and UFH groups, respectively; there was no significant difference between the two groups (χ² = 0.37, P = 0.57).

Conclusion:

In elective PCI, low-dose UFH with sequential enoxaparin has similar effects and safety to the UFH-only method.

Pre-hospital ticagrelor in ST-segment elevation myocardial infarction in the French ATLANTIC population

BACKGROUND

ATLANTIC was a randomized study comparing pre- and in-hospital treatment with a ticagrelor loading dose (LD) in ongoing ST-segment elevation myocardial infarction (STEMI). We sought to compare patient characteristics and clinical outcomes in France with other countries participating in ATLANTIC.

METHODS

The population comprised 1862 patients, 660 (35.4%) from France and 1202 from 12 other countries. The main endpoints were reperfusion (≥70% ST-segment elevation resolution) and TIMI flow grade 3 before (co-primary endpoints) and after percutaneous coronary intervention (PCI). Other endpoints included a composite ischaemic endpoint (death/myocardial infarction/stroke/urgent revascularization/definite stent thrombosis) and bleeding events at 30days.

RESULTS

In France, median times from first LD to angiography and between first and second LDs were 49 and 35min, respectively, and were similar to other countries. French patients were younger (mean 58.7 vs 61.9years, p<0.0001) and characterized by a higher rate of radial access (89.9% vs 54.8%, p<0.0001), more frequent use of pre-hospital glycoprotein (GP) IIb/IIIa inhibitors (14.1% vs 3.1%, p<0.0001) and intravenous enoxaparin (57.3% vs 10.1%, p<0.0001). In France, as in other countries, the co-primary endpoints did not differ between the two randomization groups. The composite ischaemic endpoint was numerically lower in France (3.3% vs 5.1%, p=0.07), with a lower mortality (1.4% vs 3.3%, p=0.01). PLATO major bleeding was numerically less frequent in France (1.8% vs 3.2%, p=0.07).

CONCLUSIONS

The French population appears to have better outcomes than the rest of the study population, and seems related to differences in demographics and management characteristics.

TRIAL REGISTRY

ClinicalTrials.gov (NCT01347580).

Antithrombotic therapy before, during and after emergency angioplasty for ST elevation myocardial infarction

The first three hours after symptom onset hold the maximum potential for myocardial reperfusion and salvage in ST-elevation myocardial infarction (STEMI) patients. During this period timely primary percutaneous coronary intervention (PPCI) or, when PPCI is not promptly feasible, pre-hospital administration of fibrinolyis or a glycoprotein IIb/IIIa-inhibitor (GPI) have been shown to restore coronary patency and reperfusion and even result in myocardial infarction (MI) abortion. On the other hand, oral antiplatelet therapy may not yet guarantee sufficient platelet inhibition. Patients presenting after this golden time have less, if any, benefit from an aggressive antithrombotic treatment prior to PPCI. Antithrombotic treatment during primary angioplasty should be tailored on the basis of the coronary thrombotic burden, vascular approach and the patient's risk of bleeding complications. A GPI-based approach may be favourable in patients presenting early with large MI and high thrombus burden, whereas a bivalirudin-based approach without GPI may be preferred in patients with higher bleeding risk. There are no data to support the use of GPI in bailout conditions. The powerful oral P2Y₁₂ inhibitors, prasugrel and ticagrelor, have been clearly shown to prevent stent thrombosis and recurrent ischaemic events after emergency percutaneous coronary intervention in STEMI patients. Open issues remaining are the treatment of patients with high bleeding risk, such as the elderly and those requiring anticoagulation, as well as the duration of dual antiplatelet therapy after STEMI.

Intravenous Enoxaparin Versus Unfractionated Heparin in Elderly Patients Undergoing Primary Percutaneous Coronary Intervention: An Analysis of the Randomized ATOLL Trial

Elderly (≥75 years old) patients with ST-segment elevation myocardial infarction (STEMI) have higher ischemic and bleeding risk compared with those <75 years old. We investigated the efficacy and safety of intravenous (IV) enoxaparin versus IV unfractionated heparin (UFH) in elderly patients undergoing primary percutaneous coronary intervention (PCI) for STEMI. A prespecified analysis of the Acute Myocardial Infarction Treated with Primary Angioplasty and Intravenous Enoxaparin or Unfractionated Heparin to Lower Ischemic and Bleeding Events at Short- and Long-term Follow-up (ATOLL) study was performed examining the 30-day outcomes in the elderly patients. Of the 165 elderly patients in the ATOLL study, 85 patients received IV enoxaparin 0.5 mg/kg and 80 patients received IV UFH. Intravenous enoxaparin did not reduce the primary end point, the main secondary efficacy end point, major bleeding, major or minor bleeding, and all-cause mortality compared with IV UFH. The rate of minor bleeding (5.9% vs 22.8%, P _adjusted = .01) was significantly lower with IV enoxaparin compared with IV UFH. Intravenous enoxaparin appears to be a safe alternative to IV UFH in primary PCI of the elderly patients with STEMI.

Periprocedural antithrombotic therapy during various types of percutaneous cardiovascular interventions

Percutaneous catheter-based interventions became a critically important part of treatment in modern cardiology, improving quality of life as well as saving many life. Due to the introduction of foreign materials to the circulation (either temporarily or permanently) and due to a certain damage to the endothelium or endocardium, the risk of thrombotic complications is substantial and thus some degree of antithrombotic therapy is needed during all these procedures. The intensity (dosage, combination, and duration) of periprocedureal antithrombotic treatment largely varies based on the type of procedure, clinical setting, and comorbidities. This manuscript summarizes the current therapeutic approach to prevent clotting (and bleeding) during a large spectrum of interventions: acute and elective coronary interventions, acute stroke interventions and elective carotid stenting, electrophysiology procedures, interventions for structural heart disease, and peripheral arterial interventions.

Incidence and consequence of major bleeding in primary percutaneous intervention for ST-elevation myocardial infarction in the era of radial access: an analysis of the international randomized Acute myocardial infarction Treated with primary angioplasty and intravenous enoxaparin Or unfractionated heparin to Lower ischemic and bleeding events at short- and Long-term follow-up trial

AIMS

The aims of the study are to compare the outcome with and without major bleeding and to identify the independent correlates of major bleeding complications and mortality in patients described in the ATOLL study.

METHODS

The ATOLL study included 910 patients randomly assigned to either 0.5 mg/kg intravenous enoxaparin or unfractionated heparin before primary percutaneous coronary intervention. Incidence of major bleeding and ischemic end points was assessed at 1 month, and mortality, at 1 and 6 months. Patients with and without major bleeding complication were compared. A multivariate model of bleeding complications at 1 month and mortality at 6 months was realized. Intention-to-treat and per-protocol analyses were performed.

RESULTS

The most frequent bleeding site appears to be the gastrointestinal tract. Age >75 years, cardiac arrest, and the use of insulin or >1 heparin emerged as independent correlates of major bleeding at 1 month. Patients presenting with major bleeding had significantly higher rates of adverse ischemic complications. Mortality at 6 months was higher in bleeders. Major bleeding was found to be one of the independent correlates of 6-month mortality. The addition or mixing of several anticoagulant drugs was an independent factor of major bleeding despite the predominant use of radial access.

CONCLUSIONS

This study shows that major bleeding is independently associated with poor outcome, increasing ischemic events, and mortality in primary percutaneous coronary intervention performed mostly with radial access.

The Transradial Approach and Antithrombotic Therapy: Rationale and Outcomes

This article reviews antithrombotic strategies for percutaneous coronary interventions according to the access site and the current evidence with the aim of limiting ischemic complications and preventing radial artery occlusion (RAO). Prevention of RAO should be part of the quality control of any radial program. The incidence of RAO postcatheterization and interventions should be determined initially using the echo-duplex and then frequently assessed using the more cost-effective pulse oximetry technique. Any evidence of higher risk of RAO should prompt internal analysis and multidisciplinary mechanisms to be put in place.

Interaction between access choice and pharmacotherapy for coronary intervention: the results of a UK survey

INTRODUCTION

Percutaneous coronary intervention (PCI) has changed significantly over the past decade with the uptake of radial access and the development of newer and more potent antiplatelets and safer antithrombins. This survey examined the default access route and pharmacology choice and their interaction in UK interventional practice.

METHODS

An email-based survey invited interventional cardiologists to answer questions regarding arterial access and pharmacology use during PCI. Respondents were categorised into femoral, radial and radial(+) (if the other radial was used rather than femoral if the right radial attempt failed). Data were analysed using χ(2) or the Student t test.

RESULTS

81% of the 204 respondents reported the radial artery as their default access site with a significant interaction between years since qualification and access choice (21.1 years for radial(+) vs 23 years for radial (p=0.027) vs 26.6 years for femoral (p=0.013) vs radial (p=0.0005) vs radial(+)). There were 19 different combinations of access and pharmacology reported. For non-ST elevation myocardial infarction PCI, there was a significant trend for radial(+) and radial operators to favour ticagrelor or tailored therapy versus femoral operators (54.8% vs 47.8% vs 35%, respectively, p=0.018). For primary PCI (PPCI), radial(+) and radial operators were much more likely to choose ticagrelor or prasugrel than femoral operators (77.2% (p<0.001) vs 73.9% (p=0.023) vs 50%, respectively (p<0.0001) for trend). For PPCI, glycoprotein inhibitor use was similar between groups (26.1% vs 25%, not significant); radial operators were much more likely to choose bivalirudin (52.8% vs 10%, p<0.0001) and much less likely to use heparin only (19.8% vs 65%, p<0.0001) than femoral operators.

CONCLUSIONS

There is a significant interaction between years since qualification and access choice. Although there is no established consensus on access site or drugs, default radial operators are significantly more likely to utilise new generation antiplatelets and bivalirudin than femoral operators.

Contemporary anticoagulation therapy in patients undergoing percutaneous intervention

The proper use of anticoagulants is crucial for ensuring optimal patient outcomes post percutaneous interventions in the cardiac catheterization laboratory. Anticoagulant agents such as unfractionated heparin, a thrombin inhibitor; low-molecular weight heparins, predominantly Factor Xa inhibitors; fondaparinux, a Factor Xa inhibitor and bivalirudin, a direct thrombin inhibitor have been developed to target various steps in the coagulation cascade to prevent formation of thrombin. Optimal anticoagulation achieves the correct balance between thrombosis and bleeding and is related to optimal outcomes with minimal complications. This review will discuss the mechanisms and appropriate use of current and emerging anticoagulant therapies used during percutaneous interventions.