165 SHORT DAPT STRATEGIES AFTER ACUTE CORONARY SYNDROMES: A SYSTEMATIC REVIEW AND METANALYSIS
Authors: Laudani Claudio , Spagnolo Marco , Occhipinti Giovanni , Greco Antonio , Scalia Lorenzo , Agnello Federica Giuseppa , Legnazzi Marco , Mauro Maria Sara , Rochira Carla , Tamburino Ceorrado , Capodanno Davise 
Published: December 2022

Abstract

Background
Among dual antiplatelet therapy (DAPT) modulation strategies after acute coronary syndromes (ACS), short duration of DAPT (i.e.; 3 or 6 months) received a class IIa recommendation by European guidelines. However, whether discontinuing aspirin or P2Y12 inhibitor (P2Y12-i) after this period is still a matter of debate.

Aims
The aim of this study was to compare the overall effects of short DAPT versus standard DAPT in patients presenting with ACS undergoing percutaneous coronary intervention in a two-arm metanalysis, and the relative merits of short DAPT followed by aspirin or P2Y12-i discontinuation in a three-node network meta-analysis using standard DAPT as common comparator.

Methods
Randomized trials of DAPT modulation strategies in patients with ACS undergoing PCI were identified. All-cause death was the primary outcome. Secondary outcomes included net adverse cardiovascular events (NACE), major adverse cardiovascular events (MACE), and their components. Firstly, we conducted a two-arm random-effect frequentist meta-analysis to compare short DAPT and standard DAPT. Secondly, we conducted a frequentist random-effects network metanalysis to compare the relative merits of the two short DAPT strategies. Treatments were ranked on the basis of p-scores.

Results
Nineteen studies encompassing 37,789 patients were included. The transitivity assumption was fulfilled. Comparing short DAPT with standard DAPT, no significant differences were noted for the primary outcome, but short DAPT significantly reduced the risk ratio (RR) for any bleeding (RR, 0.68; 95% CI, 0.58 to 0.79), major bleedings (RR, 0.57; 95% CI, 0.41 to 0.78) and minor bleeding (RR, 0.80; 95% CI, 0.64 to 0.98), without increasing the risk for ischemic events. In the three-node network metanalysis, no significant differences were noted in the primary endpoint, all secondary ischemic outcomes and minor bleeding between the three strategies. However, short DAPT followed by aspirin discontinuation significantly reduced the incidence of any bleeding (RR, 0.61; 95% CI, 0.50 to 0.75) and major bleeding (RR, 0.51; 95% CI, 0.37 to 0.70) compared with standard DAPT. The ranking evaluation revealed that short DAPT followed by aspirin discontinuation had the highest probability of being the best treatment for prevention of the primary endpoint, MACE, cardiovascular death, stroke, any bleeding and major bleeding (p-scores 0.78, 0.80, 0.85, 0.73, 0.98, 0.97, respectively), whereas standard DAPT had the highest probability of being the best treatment for prevention of myocardial infarction and stent thrombosis (p-scores 0.84 and 0.79, respectively).

Conclusions
In patients with ACS undergoing PCI, there was no difference in all-cause death between short DAPT regimens and standard DAPT. However, short DAPT reduced the risk of all types of bleeding, and the major driver for this effect is represented by short DAPT followed by aspirin discontinuation, which significantly reduced the risk for any bleeding and major bleeding. These data suggest that, when a short DAPT course is chosen after an ACS, discontinuing aspirin should be the strategy of choice, rather than discontinuing the P2Y12-i.