Left atrial appendage (LAA) occlusion procedures are designed to reduce the risk of thromboembolism in patients who have non-valvular atrial fibrillation, but a study presented at the 2023 Transcatheter Cardiovascular Therapeutics annual meeting in San Francisco demonstrated that about half of patients continue to have LAA leaks – and potentially the risk of dangerous blood clots and stroke – a year after the procedure.

Boston Scientific Corp. and Abbott Laboratories continue to parry over clinical trials comparing the latter’s Amplatzer Amulet with Boston Scientific’s Watchman in sealing the heart’s left atrial appendage (LAA) to prevent ischemic stroke in patients with atrial fibrillation (Afib). In one of five presentations at the 34th Transcatheter Cardiovascular Therapeutics annual scientific symposium in Boston in mid-September, Abbott said device-related thrombosis or peri-device leak more frequently preceded strokes in patients with Watchman compared to those with Abbott’s Amplatzer Amulet device.

The race is on. After six years as the only FDA approved devices for left atrial appendage closure, Boston Scientific Corp.’s Watchman products face a challenger, Abbott Laboratories’ Amplatzer Amulet. With the Amulet’s FDA approval in mid-August and positive results in a head-to-head trial presented at the 2021 European Society of Cardiology Congress on Tuesday, the Watchman has reason to look over its shoulder at a competitor that could change the game entirely. The trial results were published simultaneously in Circulation.

Abbott Laboratories received FDA approval for its Amplatzer Amulet left atrial appendage occluder to treat people with atrial fibrillation who are at risk of ischemic stroke about a month earlier than generally expected, given the backlog at the FDA. The dual-closure device closes the left atrial appendage during the procedure, reducing the risk of blood clots immediately and eliminating the need for blood thinners both during the healing process and longer term.

The U.S. FDA has given its nod for a new trial of Abbott Laboratories’ Amplatzer Amulet left atrial appendage (LAA) occluder for those with atrial fibrillation (AF) who are at risk of stroke. Known as the CATALYST trial, it is the first study comparing the effectiveness of a LAA closure device to non-vitamin K antagonist oral anticoagulant (NOAC) drugs, a newer class of blood thinners, the Abbott Park, Ill.-based company said.