Cost effectiveness of LAA closure in patients with AF and contraindications to warfarin: comment

We read with great interest the recent report on the time to cost effectiveness of different stroke reduction strategies in atrial fibrillation by Reddy et al. in your journal.1 This study evaluated the costs of percutaneous left atrial appendage closure (LAAC) using the Watchman device (Boston Scientific, Marlborough, MA). As pointed out by the authors, procedures to implement percutaneous devices are associated with a 6.7% short-term risk of major complications (air embolism, major bleeding, and pericardial effusion). Moreover, the device and technical platform necessary for the procedure come at a significant cost (€9136). Despite these downsides, assuming a willingness-to-pay threshold of €30 000 per quality-adjusted life-year gained, the authors found that relative to both aspirin and apixaban, LAAC was cost effective at 8 years. Left atrial appendage closure was also likely cost effective in patients with contraindications to warfarin at 10 years. From our perspective, these compelling results regarding percutaneous LAAC highlight the gaps in knowledge surrounding opportunistic surgical LAAC in patients undergoing another indicated cardiac surgery procedure. Opportunistic surgical LAAC comes at a minimal cost as it can successfully be performed using sutures or staples2 and does not seem to significantly prolong cross-clamp time.2,3 Additionally, small randomized controlled trials (RCTs) found no increase in post-operative complications in patients undergoing LAAC when compared with a control group; these RCTs were underpowered to definitively evaluate the impact of surgical LAAC on clinical outcomes.2,3 However, if surgical LAAC was to decrease stroke and peripheral embolism to an extent similar to percutaneous LAAC, but with lower upfront costs and risks, opportunistic surgical LAAC could become a standard of care. Despite the exciting results associated with percutaneous LAAC, caution is warranted when extrapolating results obtained with a different procedure in a distinct population. In particular, patients undergoing cardiac surgery more commonly suffer from valvular atrial fibrillation, in which it has been suggested that thrombi form more frequently outside of the left atrial appendage.4 Whether opportunistic surgical LAAC is beneficial and cost effective will be answered definitively by the ongoing Left Atrial Appendage Occlusion Study III (LAAOS III, NCT01561651), a 4700-patient RCT of surgical LAAC in patients with a history of atrial fibrillation and a CHA2SD2-VASc score of ≥2.5 As of January 2016, 1500 patients have been randomized in LAAOS III, which is expected to complete an average of 4 years of follow-up in 2020. Conflict of interest: R.P.W. has received consultancy fees from AtriCure and Armetheon. I.J. discloses research support from CCS-Bayer Cardiovascular Resident Prize and Boehringer-Ingelheim.