LAA Ligation with LARIAT Reduces Event Rates in AF

Summary

Oral anticoagulants (OACs) are effective for preventing embolic events for patients with atrial fibrillation (AF) but are associated with bleeding events. Percutaneous, image-guided, catheter-based ligation can permanently exclude the left atrial appendage (LAA), eliminating the need for OACs and reducing the risk of stroke and embolic events in patients with AF. The catheter-based LARIAT suture delivery device consists of a snare with a pretied suture that is guided over the LAA from an epicardial approach. This article discusses the results of the Lasso Occlusion of the LAA trial [LARIAT] of LAA ligation with the LARIAT device in patients with AF.

  • Arrhythmias
  • Cardiology Clinical Trials
  • Interventional Techniques & Devices
  • Cardiology & Cardiovascular Medicine
  • Arrhythmias
  • Cardiology Clinical Trials
  • Interventional Techniques & Devices

Oral anticoagulants (OACs) are effective for preventing embolic events for patients with atrial fibrillation (AF) but are associated with bleeding events. In some elderly patients, a population in which AF is common, OAC may not be a suitable therapy due to the risk of bleeding. Percutaneous, image-guided, catheter-based ligation can permanently exclude the left atrial appendage (LAA), eliminating the need for OACs and reducing the risk of stroke and embolic events in patients with AF.

The catheter-based LARIAT suture delivery device consists of a snare with a pretied suture that is guided over the LAA from an epicardial approach. The initial experience with the LARIAT device showed its efficacy for closing the LAA (97% at >90 days) with a low complication rate [Bartus K et al. J Am Coll Cardiol 2013]. Randall Lee, MD, PhD, University of California San Francisco, San Francisco, California, USA, presented the results of the Lasso Occlusion of the LAA trial [LARIAT] of LAA ligation with the LARIAT device in patients with AF.

The study objectives were to determine the efficacy of LAA closure with the LARIAT device and to assess procedural and 30-day periprocedural safety. The patient cohort consisted of 143 consecutive patients with nonvalvular AF with long-term contraindications for OAC therapy and ≥1 risk factor for embolic stroke (CHADS2 score ≥1). The patients underwent attempted LAA ligation with the LARIAT device. Long-term end points were stroke or systemic embolism (SE) and the combined end point of stroke, SE, or all-cause death.

Four patients were excluded at the time of the procedure, and 139 were treated. Closure was successful in 138 patients (99.3%). At an average follow-up of 2.2 years, 4 strokes (1 embolic) had occurred in the total population (n=139), for an event rate of 1.3% per year, compared with an expected event rate of 6.2%. In comparison, the stroke rate in the National Registry of Atrial Fibrillation at 1.2 years was 3.9% per year [Gage BF et al. JAMA 2001].

Comparing event rates across clinical trials is problematic, since trials have different inclusion and exclusion criteria; nonetheless, for the LARIAT trial, the rate of stroke and SE was 1.3% per year, and the rate of combined stroke, SE, and death was 3.3% per year, similar to the event rates seen in other stroke prevention studies for patients with AF. The Aristotle study [Granger CB et al. N Engl J Med 2011] had a stroke and SE rate at 1.8 years of 1.27% per year in the apixaban arm and 1.6% in the warfarin arm and a stroke, SE, and death rate of 4.49% with apixaban and 5.04% with warfarin. The AVERROES study [Connolly SJ et al. N Engl J Med 2011] had a stroke and SE rate of 1.6% in the apixaban arm and 3.7% in the aspirin arm and a stroke, SE, and death rate of 4.2% with apixaban and 6.4% with aspirin.

Procedural adverse events included pericardial effusion (0.7%), pulmonary embolus resulting in death (0.7%), and cardiac perforation (1.4%). Other adverse events included pericarditis (5.8%), late hemopericardium (0.7%), late pericardial effusion (0.7%), and left atrial thrombus (1.4%).

Dr. Lee concluded that LAA ligation with the LARIAT device may be an option for high-risk patients with AF who have contraindications for anticoagulation therapy. Based on these results, prospective multicenter studies are being planned to better define the efficacy and safety of LAA ligation with the LARIAT device.

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