Two randomized trials published in JACC and presented as Featured Clinical Research at TCT 2026 examine whether scaling back antithrombotic therapy, using short-term anticoagulation rather than dual antiplatelet therapy (DAPT) after left atrial appendage closure (LAAC) and omitting aspirin during primary STEMI in high-risk patients, can limit bleeding while maintaining protection against thrombotic events.

One-year results from the ANDES trial compared short-term anticoagulation with DAPT and evaluated clinical outcomes and device-related thrombosis events at one year. Approximately 500 patients were included in the trial, of whom 34.5% were women and 77% had experienced a prior bleeding event. At 60 days, most patients (~78%) in both groups switched to single antiplatelet therapy.

Overall, researchers noted the use of direct oral anticoagulants (DOACs) following LAAC was associated with improved clinical outcomes at 60 days – a clinical benefit that was maintained up to one-year later, primarily driven by a lower incidence of early minor bleeding events. No differences in thromboembolic events were observed.

Josep Rodés-Cabau, MD, PhD, et al., also observed a tendency toward increased risk of late device-related thrombosis in the DOAC group compared with the DAPT group (4.7% vs. 1.2%), particularly among patients who switched to single antiplatelet therapy at 60 days. However, they said “this finding should be considered exploratory and hypothesis generating, particularly considering the low number of events along with incomplete imaging data at one year, and will need confirmation in future trials.”

In a post hoc analysis of the PREMIUM trial, researchers evaluated whether high-bleeding risk (HBR) modifies the impact of aspirin omission in STEMI patients undergoing primary PCI.

Shintaro Inaba, MD, et al., compared the primary outcome of a 12-month composite of all-cause death, stroke, or myocardial infarction and major bleeding based on HBR status among more than 2,000 patients. Results showed a primary outcome event occurred more frequently among those assigned to monotherapy vs. DAPT. In HBR patients assigned to monotherapy, 18% experienced an event compared with 14.5% assigned to DAPT, while 7.4% of non-HBR patients in the monotherapy group had an event compared with 5.0% in the DAPT group.

“[Academic Research Consortium–HBR criteria] identified patients with a substantially higher overall risk after primary PCI for STEMI but did not identify a subgroup with a more favorable treatment effect of upfront aspirin omission,” said Inaba and colleagues. “… These findings do not support using HBR status alone to guide upfront aspirin omission and should be interpreted in the context of the low-dose prasugrel regimen used in Japan.”

Explore more simultaneously published research through JACC Journals’ TCT 2026 Coverage, and visit ACC’s TCT Meeting Coverage for additional studies, clinical insights and news from the meeting.

Clinical Topics: Anticoagulation Management, Invasive Cardiovascular Angiography and Intervention, Stable Ischemic Heart Disease, Vascular Medicine, Interventions and Vascular Medicine, Chronic Angina

Keywords: Transcatheter Cardiovascular Therapeutics, TCT26, Percutaneous Coronary Intervention, ST Elevation Myocardial Infarction, Anticoagulants, Hemorrhage, Thrombosis, Aspirin, Stroke