Duration of dual antiplatelet therapy and stability of coronary heart disease: a 60 000-patient meta-analysis of randomised controlled trials

Paired risk scores to predict ischaemic and bleeding risk twenty-eight days to one year after an acute coronary syndrome

OBJECTIVE

The recommended duration of dual anti-platelet therapy (DAPT) following acute coronary syndrome (ACS) varies from 1 month to 1 year depending on the balance of risks of ischaemia and major bleeding. We designed paired ischaemic and major bleeding risk scores to inform this decision.

METHODS

New Zealand (NZ) patients with ACS investigated with coronary angiography are recorded in the All NZ ACS Quality Improvement registry and linked to national health datasets. Patients were aged 18-84 years (2012-2020), event free at 28 days postdischarge and without atrial fibrillation. Two 28-day to 1-year postdischarge multivariable risk prediction scores were developed: (1) cardiovascular mortality/rehospitalisation with myocardial infarction or ischaemic stroke (ischaemic score) and (2) bleeding mortality/rehospitalisation with bleeding (bleeding score).

FINDINGS

In 27 755 patients, there were 1200 (4.3%) ischaemic and 548 (2.0%) major bleeding events. Both scores were well calibrated with moderate discrimination performance (Harrell's c-statistic 0.75 (95% CI, 0.74 to 0.77) and 0.69 (95% CI, 0.67 to 0 .71), respectively). Applying these scores to the 2020 European Society of Cardiology ACS antithrombotic treatment algorithm, the 31% of the cohort at elevated (>2%) bleeding and ischaemic risk would be considered for an abbreviated DAPT duration. For those at low bleeding risk, but elevated ischaemic risk (37% of the cohort), prolonged DAPT may be appropriate, and for those with low bleeding and ischaemic risk (29% of the cohort) short duration DAPT may be justified.

CONCLUSION

We present a pair of ischaemic and bleeding risk scores specifically to assist clinicians and their patients in deciding on DAPT duration beyond the first month post-ACS.

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.

Short-term DAPT after coronary stenting has similar ischemic and bleeding outcomes as long-term DAPT: a 5-year population-based cohort study

BACKGROUND

Optimal duration of dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI) remains controversial.

AIM

We investigated the relationship between DAPT duration following PCI and long-term ischemic and bleeding outcomes under real-world conditions.

METHODS

Patients aged ≥ 65 years who underwent PCI with stenting in Western Australian hospitals between 2003 and 2008 and survived 2 years were identified from linked hospital admissions data. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE) defined as a composite of all-cause death and admissions for acute coronary syndrome (ACS), coronary artery revascularization procedure, stroke, and major bleeding. Secondary outcomes were ACS admissions, all-cause death, and major bleeding admissions. Patients were followed up for 5 years from initial PCI.

RESULTS

A total of 3963 patients were included in the final analysis. The mean age of the cohort was 74.5 ± 6.1 years with 67.3% males. No significant difference was seen with 6-12, 12-18, or 18-24 months DAPT, compared to 0-6 months DAPT duration for MACCE and all secondary outcomes at 3- and 5-year post-PCI.

CONCLUSION

There is no significant difference in both bleeding and ischemic outcomes in long-term DAPT as compared to short-term DAPT for first- and second-generation drug-eluting stents in a real-world population.

Optimal Antithrombotic Therapy in Patients Undergoing Percutaneous Coronary Intervention: A Focused Review on High Bleeding Risk

Dual antiplatelet therapy (DAPT) is a therapeutic cornerstone to prevent stent thrombosis following percutaneous coronary intervention (PCI) for coronary artery disease (CAD). However, the longer the DAPT duration, the higher the incidence of bleeding and mortality. Since the advent of second-generation drug-eluting stents (DES), the continuous evolution of DES has reduced the thrombotic risk and allowed for a shorter DAPT duration. On the other hand, concerns on the elevated risk of bleeding during antithrombotic therapy have been further raised due to the growing number of elderly CAD patients with multiple comorbidities. The consequent debate topic over post-PCI antithrombotic therapy has shifted from simply reducing thrombotic risk to safely minimizing bleeding risk. Due to the significant impact of bleeding on clinical outcomes, including prognosis, current guidelines on antithrombotic therapy for CAD prioritize stratification of patients at a high bleeding risk (HBR) as the top consideration in determining post-PCI antithrombotic therapy. Achieving optimal antithrombotic therapy for each patient undergoing PCI requires a better understanding of the clinical variables constituting the balance of bleeding and thrombotic risk. This review highlights relevant evidence required to optimize antithrombotic therapy for HBR patients undergoing PCI.