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Important correction: Watchman devices not as effective as I thought

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/320601935/m/5650017125

August 08, 2026, 10:03 AM
sjtill
Important correction: Watchman devices not as effective as I thought
I recently posted in the "palpitations" thread about the Watchman device, which occludes the left atrial appendage, and is supposed to reduce the risk of stroke in patients with atrial fibrillation.
A recent excellent Substack post by a cardiologist, John Mandrola, brought to my attention that these devices have NOT been proven successful in reducing mortality or ischemic stroke (from blood clot) risk.
I asked Grok to verify this statement, and it did:

quote:
Core evidence from pivotal trials
The foundational RCTs for the Watchman device (PROTECT AF and PREVAIL) compared LAAO to warfarin:

Ischemic stroke: Numerically higher with the device. In the patient-level meta-analysis of the two trials (5-year follow-up), the hazard ratio for ischemic stroke/systemic embolism was approximately 1.7 (favoring warfarin; not always statistically significant depending on the analysis and whether procedure-related events were excluded).
Overall stroke/systemic embolism rates were similar because lower hemorrhagic stroke rates with LAAO offset the ischemic excess.
Mortality benefits (when seen) were driven more by reductions in hemorrhagic events and non-procedure-related bleeding than by superior ischemic stroke prevention.
These trials used warfarin (not modern DOACs) as the comparator and had notable procedural complications in the early experience.

More recent RCTs

CLOSURE-AF (NEJM 2026; high-risk older patients, mean CHA₂DS₂-VASc ~5.2, mostly DOAC-based medical therapy): LAAO failed to meet noninferiority for the composite of stroke, systemic embolism, major bleeding, or cardiovascular/unexplained death. Event rates favored medical therapy (≈16.8 vs 13.3 per 100 patient-years). Stroke rates were essentially identical between arms. This independent (non-industry-funded) trial is particularly relevant to Mandrola’s point.
OPTION (post-AF ablation patients): LAAO was noninferior to continued oral anticoagulation for a composite efficacy endpoint (death/stroke/systemic embolism) and superior for non-procedure-related bleeding.
CHAMPION-AF: LAAO met noninferiority versus NOACs for cardiovascular death/stroke/systemic embolism and was superior for non-procedure-related bleeding. Ischemic stroke rates were numerically higher with the device in some breakdowns.

Meta-analyses of RCTs
Pooled analyses of percutaneous LAAO versus oral anticoagulation generally show:

Similar or non-significantly higher rates of ischemic stroke/systemic embolism with the device. Lower rates of hemorrhagic stroke and non-procedure-related major bleeding. Mixed or modest effects on all-cause/cardiovascular mortality (some analyses favor LAAO, driven by bleeding reduction; others show no difference). Overall stroke rates usually comparable.

Absolute ischemic stroke rates after successful LAAO in contemporary practice are low (often ~1–2% per year), but they do not consistently beat well-managed anticoagulation.


The bottom line is that the devices should be recommended only for high-risk patients who cannot tolerate anticoagulation.

Now I go to inform my wife that the Watchman is not the solution we thought it was. Newer anticoagulants, e.g. Eliquis, are safer and more effective than warfarin, which was the original comparison in trials of the Watchman. So medications are likely safer overall.

By the way this cardiologist, Dr. Mandrola, is an electrophysiology specialist, and he doesn't think much of ablation of atrial fibrillation--becasue unlike other ablation procedures, it is not curative. 70% successful each time, can be repeated. But the underlying AF which arises from the pulmonary veins is still there, just electrically "isolated" by scarring the tide around the pulmonary veins where they meet the left atrium.


_________________________
“Good intentions will always be pleaded for every assumption of authority. It is hardly too strong to say that the Constitution was made to guard the people against the dangers of good intentions. There are men in all ages who mean to govern well, but they mean to govern. They promise to be good masters, but they mean to be masters. –Daniel Webster (1782-1852)"
August 08, 2026, 05:53 PM
Some Shot
Thanks for the information, and the "bottom line".

This supports the course my Dr. put me on and I have faith in him.

I noticed that early this year, Watchman was buying a lot of advertising around here. Currently, very little (maybe none).
August 09, 2026, 12:21 AM
armedmd
Thank you for the update doc. As a trauma surgeon I hate most anticoagulants and anti platelet agents and favor mechanical prophylactic devices since they don’t theoretically increase morbidity and mortality in trauma. As is often the case the latest greatest may not be the greatest longterm. Clearly there is still some indication for the watchman but definitely not as widespread as the manufacturer would lead you to believe.


Build a man a fire and keep him warm for a night, set a man on fire and keep him warm the rest of his life.
August 09, 2026, 08:43 AM
UTsig
Well, I guess I'll be having a conversation with my EP. As much as I'd like to get off Eliquis it might not be good idea. Thanks, really appreciate your follow up.



"Nature scares me" a quote by my friend Bob after a rough day at sea.
August 09, 2026, 09:39 AM
Scooter123
January of 2025 I had a Cardiac Ablation. It took a bit of time but I have been 100% AFIB free since late May 2025.

March 28, 2026 I went to the hospital for a Hemoglobin Crisis, it was down to 6.3. Cause was a combination of Plavix, and Xaralto. BTW got scoped from stem to stern and no obserevable bleeding site were seen. Also had the camera you swallow with no observable bleeding. The solution was a complete change in medication. I how take Eliquis and 1 baby aspirin.

Watchman. I have 2 cardioligists at present, one a rhythm specialist and the other a general cardiologist. My rhythm specialist recommended the Watchman at one point. I got on Google and discovered that the average survival time for those with this device is only 5 years after installation. That was an absolute NO GO for me. At present weather permitting I am out at 7:00 AM for a 2-3 mile walk at a 17 minute per mile pace. BTW prior to 18 months of AFIB issues in 20-23 to end of 2024 I was able to do the mile in 13 minutes 25 seconds and average 14/30 for long distance. At 71 years old I find it difficult to build strength but I'm taking it 1 day at a time. Also learned to NOT push too hard, face plants really hurt.


I've stopped counting.
August 09, 2026, 11:06 AM
Flashlightboy
I had PFA on June 4 after two failed cardioversions. Early 12 lead suggests Afib reduced but now have atrial mitral flutter.

Amio 400mg and Eliquis for now.

Will reassess this week but I'm thinking a revision is in my future. Amio reduced the HR but the side effects are nasty.