Cardiovascular Atlas
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Left atrial appendage occlusion

The left atrial appendage is a small pouch off the heart's upper left chamber. Closing it off is meant to stop clots from forming there and causing a stroke. NHLBI describes this for people who cannot take blood thinners. In the PROTECT AF trial, which enrolled people who were eligible for warfarin, percutaneous closure with a device did not do worse than warfarin for the trial's main outcome, but it had more serious safety events, mostly linked to the procedure. NHLBI also cautions that complete closure is hard to achieve and that a leak leaves some clotting risk.

Also called LAA closure · Left atrial appendage closure · LAAO

  • Technology
  • In this atlas

Overview

Technical summary

MeSH descriptor D000097546 (Left Atrial Appendage Closure). Percutaneous closure was tested in PROTECT AF with the WATCHMAN device. NHLBI says surgeons may also deal with the appendage during surgical ablation or other heart surgery. The US approval of WATCHMAN (PMA P130013) is for people who are suitable for warfarin and have a rationale to seek a non-drug alternative; the patient population that NHLBI describes (people who cannot take blood thinners) and the population approved in the US label wording are not the same, and the sources read do not reconcile them.

How it works

A device or a surgical closure blocks off the left atrial appendage so that clots cannot form there and cause a stroke (NHLBI). Percutaneous closure places a device without open surgery (PROTECT AF).

Strengths

  • In PROTECT AF, closure with the WATCHMAN device and discontinuation of warfarin was non-inferior to warfarin for a composite of stroke, cardiovascular death and systemic embolism (probability of non-inferiority more than 99.9%).
  • It gives people who cannot take blood thinners an option, according to NHLBI.

Limitations

  • Primary safety events were more frequent with the device than with warfarin in PROTECT AF (7.4 compared with 4.4 per 100 patient-years; rate ratio 1.69, credible interval 1.01 to 3.19), mainly from periprocedural complications according to the authors.
  • NHLBI cautions that complete closure is hard to achieve and that a leak leaves some clotting risk.
  • The efficacy rate ratio in PROTECT AF (0.62, credible interval 0.35 to 1.25) includes 1.

Required infrastructure

  • A procedure by a provider: percutaneous placement of a device (PROTECT AF), or closure of the appendage during surgical ablation or other heart surgery (NHLBI).

Claims and evidence

No claims are published for this technology yet.

Record details

Record id
cardio:left-atrial-appendage-occlusion
Content hash
c0c06fe2aa1523b365faa831966a63d6eebe08e8489db407927cca1492d4f74e