Dual antiplatelet therapy (DAPT) was found to have a similar safety profile to oral anticoagulation (OAC) with aspirin after left atrial appendage occlusion (LAAO) with the Watchman FLX, according to a study published in JACC: Cardiovascular Interventions on Nov. 8.

Using data from the NCDR LAAO Registry, Megan Coylewright, MD, MPH, FACC, et al., included 49,968 patients (mean age 77 years, 40% women, median CHA₂DS₂-VASc score 5.0) undergoing Watchman FLX implantation between Aug. 5, 2020 to Sept. 30, 2021. Discharge medication regimens – DAPT, direct oral anticoagulation (DOAC)/aspirin, or warfarin/aspirin – were compared with 1:1 propensity-matched analyses. The authors evaluated a composite endpoint of death, stroke, major bleeding and systemic embolism. They also looked at individual components of the composite endpoint and device-related thrombus between discharge and 45 days postprocedure.

Following propensity score matching, results found the 45-day composite endpoint rates were similar comparing DAPT to DOAC/aspirin (3.44% vs. 4.06% respectively; p=0.13) and DAPT to warfarin/aspirin (3.23% vs. 3.08% respectively; p=0.75). In addition, death, stroke and device-related thrombus were similar among the groups.

The study authors also note that rates of major bleeding were slightly higher in patients who received DOAC/aspirin (DAPT 2.48% vs. DOAC/aspirin 3.25%, p=0.04; and DAPT 2.25% vs. warfarin/aspirin 2.22%, p=0.93).

“A significantly lower risk of bleeding was noted when DAPT was prescribed post-LAAO compared with DOAC/aspirin,” write the authors. “These data also demonstrate that great variability exists for postprocedure medications following LAAO, illustrating the challenge of balancing the rare risk of [device-related thrombus (DRT)]-related stroke with bleeding following LAAO.”

In an accompanying editorial comment, Matthew W. Sherwood, MD, MHS, FACC, and Amit N. Vora, MD, MPH, FACC, add, “it is our hope that answers will arrive with new technologies that could alter the treatment landscape. The next-generation Watchman FLX Pro device has been redesigned with a polymer coating (HEMO-COAT) that will theoretically encourage more rapid endothelialization and potentially reduce rates of DRT.”

Geoffrey D. Barnes, MD, MSc, FACC, provides additional perspective in an ACC.org Journal Scan, stating: “While limited by a retrospective design, this large and well-conducted study provides reassurance to clinicians that both an OAC plus aspirin and DAPT approach post Watchman FLX LAAO provide similar clinical outcomes across a composite of thrombotic and hemorrhagic complications.”