Real-world safety and efficacy of WATCHMAN LAA closure at one year in patients on dual antiplatelet therapy: results of the DAPT subgroup from the EWOLUTION all-comers study.

AIMS

The study aimed to confirm the efficacy and safety of WATCHMAN LAA closure in atrial fibrillation patients unsuitable for oral anticoagulation.

METHODS AND RESULTS

The EWOLUTION registry prospectively collects all clinical data on 1,005 European patients implanted with a WATCHMAN device. Following the procedure, 605 patients (60.2%) received dual antiplatelet therapy according to the local standard; DAPT was discontinued in 85% of patients within one year. CHA2DS2-VASc and HAS-BLED scores were 4.61.6 and 2.41.2, respectively. The periprocedural SAE rate was 3.3% (2.0% major adverse cardiac events), mostly resolving without sequelae. Device embolisation or pericardial effusion occurred in one (0.2%) and two (0.3%) patients, respectively. TEE (median 62 days post implant, IQR: 47-97) confirmed effective sealing (no leak >5 mm) in 99.2% of patients. Device thrombus was present in 22 patients (4.0%), one patient developed a stroke. One-year mortality in the DAPT group was 9.6% (N=58) reflecting the advanced age and comorbidities in this population. The ischaemic stroke rate at one year was 1.4% (expected based on CHA2DS2-VASc: 7.5%), none fatal. The major bleeding rate was 2.5%, or 2.1% excluding periprocedural events (expected rate on VKA based on HAS-BLED: 5.1%).

CONCLUSIONS

LAA closure with the WATCHMAN device followed by DAPT therapy in a high-risk patient population is safe. At one year, the intervention is associated with a substantial risk reduction regarding ischaemic stroke and major bleeding compared to the expected rate based on CHA2DS2-VASc and HAS-BLED scores.