An interventional study of WATCHMAN FLX Pro LAAC Device in Atrial Fibrillation, Bleeding and Stroke, sponsored by Boston Scientific Corporation. Completed at 45 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-11-04.
Sponsored by Boston Scientific Corporation · Not applicable, Interventional, and Treatment
The primary objective of this study is to collect real-world data on WATCHMAN FLX™ Pro Left Atrial Appendage Closure (LAAC) Device in patients with non-valvular atrial fibrillation.
3,870 studies on the registry are indexed under Atrial Fibrillation; 924 are open to participants now.
This study's enrollment of 949 is above the median of 144 across 2,380 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →Boston Scientific Corporation is the lead sponsor of 517 studies on the registry; 38 are open to participants now.
Of its 64 completed or terminated interventional studies of FDA-regulated products, 56 (88%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
WATCHMAN FLX Pro LAAC Device Implantation
Device: WATCHMAN FLX Pro LAAC Device
Treatment with a WATCHMAN FLX Pro Left Atrial Appendage Closure Device
Also known as: Left Atrial Appendage Closure
Primary Efficacy Endpoint: The Rate of Device Leak >5 mm at 45-day Post-Implant TEE for the Primary Analysis Subjects
Incomplete seal with peri-device gap \> 5mm in the primary analysis subset implanted patients with 45-day TEE imaging (as assessed by the core lab).
Time frame: 45 days
Primary Safety Endpoint: Composite Rate of All-cause Mortality, All Stroke, Systemic Embolism, and Major Bleeding for the Primary Analysis Subjects
Composite CEC-adjudicated all-cause mortality, all stroke, systemic embolism, and major bleeding in the Intention to Treat (ITT) population at 6 months.
Time frame: 6 months
| Milestone | Primary Analysis Subset |
|---|---|
| Started | 500 |
| 45-day follow-up | 494 |
| 6-month follow-up | 474 |
| Completed | 474 |
| Not completed | 26 |
| Withdrew: Death | 16 |
| Withdrew: Withdrawal by subject | 4 |
| Withdrew: Physician decision | 1 |
| Withdrew: Missed visit | 2 |
| Withdrew: Other | 3 |
Incomplete seal with peri-device gap \> 5mm in the primary analysis subset implanted patients with 45-day TEE imaging (as assessed by the core lab).
| Participants | Primary Analysis Subset |
|---|---|
| Primary Efficacy Endpoint: The Rate of Device Leak >5 mm at 45-day Post-Implant TEE for the Primary Analysis Subjects | 0 |
Composite CEC-adjudicated all-cause mortality, all stroke, systemic embolism, and major bleeding in the Intention to Treat (ITT) population at 6 months.
| Participants | Primary Analysis Subset |
|---|---|
| Primary Safety Endpoint: Composite Rate of All-cause Mortality, All Stroke, Systemic Embolism, and Major Bleeding for the Primary Analysis Subjects | 54 |
Collected over Study events are reported from enrollment through Day 180, with the exception of All-Cause Mortality which includes mortalities reported from enrollment through 6-month follow-up visit completion, or end of the 6-month visit window (210 days) when the visit was missed.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Primary Analysis Subset | 16/500 (3.2%) | 141/500 (28.2%) | 70/500 (14%) |
| Event | Primary Analysis Subset |
|---|---|
| Atrial fibrillationCardiac disorders | 13/500 |
| Gastrointestinal haemorrhageGastrointestinal disorders | 12/500 |
| Cardiac failure acuteCardiac disorders | 11/500 |
| Cardiac failure congestiveCardiac disorders | 9/500 |
| Acute respiratory failureRespiratory, thoracic and mediastinal disorders | 7/500 |
| Acute kidney injuryRenal and urinary disorders | 6/500 |
| PneumoniaInfections and infestations | 5/500 |
| Urinary tract infectionInfections and infestations | 5/500 |
| FallInjury, poisoning and procedural complications | 5/500 |
| Cerebrovascular accidentNervous system disorders | 5/500 |
| Event | Primary Analysis Subset |
|---|---|
| EpistaxisRespiratory, thoracic and mediastinal disorders | 10/500 |
| ContusionInjury, poisoning and procedural complications | 7/500 |
| HaematomaVascular disorders | 5/500 |
| Gastrointestinal haemorrhageGastrointestinal disorders | 4/500 |
| Pericardial effusionCardiac disorders | 3/500 |
| Catheter site haemorrhageGeneral disorders | 3/500 |
| Device related thrombosisGeneral disorders | 3/500 |
| FallInjury, poisoning and procedural complications | 3/500 |
| HaematuriaRenal and urinary disorders | 3/500 |
| Gingival bleedingGastrointestinal disorders | 2/500 |
| Age, Customized(Participants) | Primary Analysis Subset |
|---|---|
| <75 years | 188 |
| ≥ 75 years | 312 |
| Sex: Female, Male(Participants) | Primary Analysis Subset |
|---|---|
| Female | 194 |
| Male | 306 |
| Ethnicity (NIH/OMB)(Participants) | Primary Analysis Subset |
|---|---|
| Hispanic or Latino | 13 |
| Not Hispanic or Latino | 471 |
| Unknown or Not Reported | 16 |
| Race (NIH/OMB)(Participants) | Primary Analysis Subset |
|---|---|
| American Indian or Alaska Native | 1 |
| Asian | 4 |
| Native Hawaiian or Other Pacific Islander | 2 |
| Black or African American | 20 |
| White | 441 |
| More than one race | 0 |
| Unknown or Not Reported | 3 |
| Region of Enrollment(participants) | Primary Analysis Subset |
|---|---|
| United States | 500 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — The data and study protocol for this clinical trial may be made available to other researchers in accordance with the Boston Scientific Data Sharing Policy ( https://www.bostonscientific.com/en-US/data-sharing-requests.html).
Supporting information: Study protocol, Sap
This study is completed, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.
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