Left atrial appendage closure versus medical therapy in patients with atrial fibrillation: the APPLY study

Aims: Left atrial appendage closure (LAAC) with AMPLATZER occluders is used for stroke prevention in atrial fibrillation (AF). Net clinical benefit compared to medical therapy has not been tested. The aim of this study was to test whether long-term clinical outcome after LAAC with AMPLATZER occluders may be similar to medical therapy.

Methods and results: Five hundred consecutive patients who underwent LAAC with AMPLATZER occluders were compared to 500 patients with medical therapy by propensity score matching. The primary efficacy endpoint was a composite of stroke, systemic embolism and cardiovascular/unexplained death. The primary safety endpoint consisted of major procedural adverse events and major bleedings. For assessment of net clinical benefit, all of the above-mentioned hazards were combined. After 2,645 patient-years at a mean follow-up of 2.7±1.5 years, the primary efficacy endpoint was reached by 75/1,342, 5.6% in the LAAC group versus 102/1,303, 7.8% per 100 patient-years (hazard ratio [HR] 0.70, 95% confidence interval [CI]: 0.53-0.95, p=0.026). The primary safety endpoint occurred in 48/1,342, 3.6% versus 60/1,303, 4.6% per 100 patient-years (HR 0.80, 95% CI: 0.55-1.18, p=0.21), and the combined hazard endpoint in 109/1,342, 8.1% versus 142/1,303, 10.9% per 100 patient-years (HR 0.76, 95% CI: 0.60-0.97, p=0.018). Patients receiving LAAC demonstrated lower rates of both all-cause and cardiovascular mortality (111/1,342, 8.3% vs 151/1,303, 11.6% per 100 patient-years [HR 0.72, 95% CI: 0.56-0.92, p=0.005] and 54/1,342, 4.0% vs 84/1,303, 6.5% per 100 patient-years [HR 0.64, 95% CI: 0.46-0.89, p=0.007]).

Conclusions: LAAC with AMPLATZER devices showed a net clinical benefit over medical therapy by superior efficacy, similar safety and a benefit in all-cause and cardiovascular mortality.