Efficacy and Safety of the Atrial Septal Defect Closure for Patients with Absent or Malaligned Aortic Rim Using a Figulla Flex II Device Flared and Straddling Behind the Aorta

Background: Although transcatheter closure of atrial septal defect (ASD) is safe and effective for patients with sufficient rim, ASD patients with absent and/or malaligned aortic and/or superior rim have higher risks of device embolization and cardiac erosion. We have treated such high-risk patients using a Figulla Flex II (FFII) device shaped flared and straddling behind the aorta because this method would avoid such serious complications. However, its long-term efficacy and safety remain unclear. Therefore, the midterm efficacy and safety of this method were studied. Methods: We retrospectively evaluated the outcome of 47 consecutive patients with such rim (age 6-73 years, weight 17-75 kg, 31 females) treated with this method at our hospital between February 2016 and September 2019. To make the flared and straddling shape, we selected a FFII 4-6 mm larger than the balloon sizing diameter by stop-flow technique. We also studied the device shape, the disc pressure to the Valsalva wall and their changes over 6 months by transesophageal echocardiography. Results: All procedures were successful, and leakage disappeared within 1 year. During a mean follow up of 37 +/- 12 months, complications included a transient sinus node dysfunction and one I degrees atrioventricular block within 3 months. Whole device shape changed from bulky to thin: the device waist and thickness significantly decreased by around 1.5 mm and 3.5 mm, respectively (p < 0.05), but the two discs remained flared and straddling behind the aorta over 6 months; therefore, the disc edges seldom pressed the Valsalva wall perpendicularly, even though the inner plane of either disc often slightly pressed the wall. Conclusions: ASD closure using a FFII shaped flared and straddling behind the aorta is probably effective and safe for patients with absent and/or malaligned aortic and/or superior rim although requiring care for conduction disorders.