Amulet study shows high implant success rates with Amplatzer Amulet LAA occluder

St Jude Medical Aplatzer Amulet
Amplatzer Amulet

A study presented at the last late-breaking trial session of the 2016 Transcatheter Cardiovascular Therapeutics (TCT) meeting (29 October-2 November, Washington, DC, USA) indicates that the Amplatzer Amulet left atrial appendage occluder device (St Jude Medical), for the prevention of stroke in patients with atrial fibrillation, is associated with high implant success rates and a low rate of adverse effects.

The prospective, multicentre, international AMPLATZER Amulet Observational study, the largest registry of the Amplatzer Amulet LAA occluder, was presented by David Hildick-Smith (Sussex Cardiac Centre, Brighton and Sussex University Hospitals, Brighton, UK).

The registry enrolled 1,073 patients with non-valvular AF (75±8 average age, 35.6% female) between June 2015 and September 2016 at 64 clinical sites in Europe, the Middle East, Asia, Australia and South America. Sixty five per cent of the patients had a CHA2DS2-VASc score ≥4 and 72.5% of patients had prior history of major bleeding. Importantly, Hildick-Smith said, 85% of the patients had contraindication to oral anticoagulation and 9% of the patients had ischaemic stroke despite oral anticoagulation.

The study is designed to assess acute serious adverse events from zero to seven days post-procedure, acute late serious adverse events also from zero to seven days post-procedure and through two years. Report of ischaemic stroke, systemic embolism, cardiovascular death and bleeding events will be assessed through two years. The data presented at TCT included implantation success, complications from the procedure and three-month follow-up in 711 patients.

Hildick-Smith reported that out of the 1,073 patients enrolled, 1,060 patients had device implantation, which gave a technical success rate of 98.8%.

Acute device/procedure related major adverse events within seven days post-procedure occurred in 2.7% of 1,073 patients. Ischaemic stroke occurred in 0.3%, pericardial effusion requiring intervention in 0.5%, embolisation in 0.1%, and bleeding in 0.9%. Hidlick-Smith noted that there were three deaths (0.2%) that occurred within seven days of attempted implant, two of which were adjudicated as procedure or device related, and one as unrelated to the device.

At one- to three- month follow-up, the majority of patients were on antiplatelet therapy only and the CoreLab analysed results of transoesophageal echocardiography (TEE) showed a closure rate of 99% (n=364).

“These results indicate that the Amplatzer Amulet is safe and associated with low rates of periprocedural and early adverse events, as well as demonstrating high closure rates,” said Hildick-Smith. “In addition, antiplatelet therapy appears to be an effective treatment strategy post-implantation in the short term. Additional long-term data are necessary to confirm these promising early findings.”

The Amplatzer Amulet left atrial appendage occluder is CE mark approved, but remains an investigational device in the USA. In September, St Jude Medical announced the start of the AMPLATZER Amulet LAA Occluder IDE trial, evaluating the safety and effectiveness of the device. The trial will enrol patients at up to 100 sites in the USA and 50 sites internationally.