The WAVECREST PMCF Study is a prospective, non-randomized, multicenter study to confirm safety and performance of the Coherex WaveCrest Left Atrial Appendage (LAA) Occlusion System in the current medical practice setting in patients with non-valvular atrial fibrillation who are at increased risk for stroke. Up to 65 subjects may be enrolled at up to 15 study sites in Europe. Patients will be followed through 45 days post-procedure.