Reviwer : Dr. Süleyman Çağan Efe

Name of the study : Dual Antiplatelet Therapy after PCI in Patients at High Bleeding Risk MASTER DAPT

Published Congress : ESC 2021

Link : https://www.nejm.org/doi/full/10.1056/NEJMoa2108749

Background :

The duration of dual antiplatelet therapy after acute coronary syndromes is getting shorter with the development of new generation stent technologies. after randomized controlled studies, it is included in the 2020 NSTMI ESC guidelines in patients with high and very high bleeding risk 3 months and 1 month dual treatment with a recommendation level of 2a .also In the ESC revascularization guideline published in 2018, a 6-month dual treatment is included with recommendation class 2a in STEMI patients. MASTER-DAPT the randomized controlled study including patients with high bleeding risk according to BARC clasification was planned in 2018 when the recommendations were unsufficient for high bleeding risk patients

Objective:

The study was planned to evaluate the efficacy and safety of short-term and long-term dual antiplatelet therapy after sirolimus-eluting ultimaster stent implantation in patients at high risk of bleeding.

Methods :

In the study, 4579 patients were randomized to the standard and shortened dual antiplatelet arms. Patients with a history of PCI in the last 6 months and those with a previous history of bioresorbable stent were not included in the study. Patients who did not experience any ischemic event and active bleeding within an average of 30-14 days after PCI were included. In the standard DAPT arm, patients received dual therapy for at least 2 months (mean, 193 days) for up to 5 months (regardless of OAC use), while in the shortened DAPT arm, single antiplatelet therapy was switched after 1 month (mean 34 days). Use of OAC, over 75 years of age, hospitalization due to bleeding without any cause, bleeding of unknown origin in the last 12 months, HB<11 g/dl, bleeding tendency due to systemic diseases, steroid and non-steroid usage requirement . , malignancy , history of stroke at any time , history of TIA in the last 6 months and PRECISE DAPT score > 25 were taken as as a criterion for patients for high bleeding risk The three primary outcomes identified were net adverse clinical events (NACE) (death from any cause, myocardial infarction, stroke, or a combination of major bleeding), major adverse cardiac or cerebral events (MACE) (death from any cause, myocardial infarction or a composite of stroke), and major or clinical non-major bleeding. patient follow-up was evaluated in an average of 335 days. The first two outcomes were evaluated for noninferiority in the per-protocol population and the third outcome was evaluated for superiority in the intent-to-treat population.

Results :

The rates of patients treated for chronic coronary syndrome and acute coronary syndrome were similar among the groups randomized to the study, and the patients' age, gender, history of coronary disease and oral anticoagulant use requirements were similar. Among the 4434 patients in the study population, NACE occurred in 165 patients (7.5%) in the abbreviated-therapy group and in 172 (7.7%) in the standard-therapy group (difference, -0.23 percentage points; 95% confidence interval [CI], -1.80 to 1.33; P<0.001 for noninferiority). A total of 133 patients (6.1%) in the abbreviated-therapy group and 132 patients (5.9%) in the standard-therapy group had a MACE (difference, 0.11 percentage points; 95% CI, -1.29 to 1.51; P=0.001 for noninferiority). Among the 4579 patients in the intention-to-treat population, major or clinically relevant nonmajor bleeding occurred in 148 patients (6.5%) in the abbreviated-therapy group and in 211 (9.4%) in the standard-therapy group (difference, -2.82 percentage points; 95% CI, -4.40 to -1.24; P<0.001 for superiority).

Conclusion :

One month of dual antiplatelet therapy was found to be non-inferior to standard therapy in the occurrence of net adverse clinical events and major adverse cardiac or cerebral events. abbreviated therapy was also superior in reducing the incidence of major or clinically significant non-major bleeding.

Interpretation :

The MASTER DAPT study is started in 2018. ESC NSTMI , chronic coronary syndromes and revascularization guidelines were published after the study started . it is stated in these guidelines that dual therapy for patients with high bleeding risk can be shortened to 1 month in patients not using OAC and up to 1 week in those using OAC. The fact that patients who had an ischemic event and had bleeding in the first month could not be included in the study may be one of its limitations. The MASTER DAPT study is an important study in terms of being a randomized study involving patients with only high bleeding risk, and may be a valuable study in terms of raising the current recommendation classes.