Left Atrial Appendage Closure in Patients With a Mechanical Mitral Valve Prosthesis: A Multicentre Italian Pilot Study

Introduction In patients with atrial fibrillation (AF) on vitamin K antagonist (VKA) therapy and therapeutical INR range the incidence of cardiac thromboembolism is not negligible and the subgroup carrying a mechanical prosthetic mitral valve (PMV) has the highest risk. We aimed to assess the long-term effects of left atrial appendage closure (LAAC) in AF patients carriers of mechanical PMV who experienced a failure of VKA therapy. Methods In this retrospective, multicenter study, patients underwent LAAC because of thrombotic events including TIA/stroke, systemic embolism and evidence of left atrial appendage thrombosis/sludge despite VKA therapy were enrolled. Patients with mechanical PMV were included and compared with those affected by non valvular AF. The primary endpoint was the composite of all-cause death, major cardiovascular events and major bleedings at follow-up. Feasibility and safety of LAAC was also assessed. Results 55 patients (42% females; mean age 70 ± 9 years) including 12 carriers of mechanical PMV were enrolled. The most frequent indication to LAAC (71%) was LAA thrombosis or sludge. Procedural success was achieved in 96% of overall cases and in 100% of patients with PMV. In 35 patients a cerebral protection device was used. During a median follow-up of 6.1 ± 4.3 years, 4 patients with PMV and 20 patients without PMV reported adverse events (HR 0.73 [95% CI 0.25 – 2.16, p=0.564]). Conclusion LAAC seems to be a valuable alternative in AF carriers of mechanical PMV with failure of VKA therapy. This off-label, real-world clinical practice indication deserve validation in further studies.