Paper Title
Safety and Performance Evaluation of TIG-Welded Atrial Depressurized Device made from Shape Memory Alloy for Heart Failure Treatment

Abstract
Nowadays, various welding technologies have been widely used in the medical implant production process. Tungsten inert gas (TIG) welding has been utilized in the cardiovascular implant for joining dissimilar metal parts to nitinol alloy. This research aims to evaluate the performance and safety of the welding area obtained by TIG-welding technique and laser-welding technique in Atrial Depressurized Device (ADD) prototypes. In order to evaluate connecting performance, 3-repeated times advancement and deployment in a 12Fr loader were performed. In addition, a pull test was carried out to determine the safety of connecting parts according to the summary of safety and effectiveness data of the AMPLATZER Septal Occluder System. The results showed that among three prototypes, one TIG-welded prototype was damaged at the left atrial disc during performance testing. In the safety evaluation, among three prototypes, two TIG-welded were damaged when subjected to load at 24.7N and 21N. However, the laser-welded prototype met the acceptance criteria without damage during performance and safety evaluation. Therefore, it can be concluded that the laser-welding is recommended ADD stent fabrication. Keywords - Hfp EF, TIG Welding, Shape Memory Alloy, Delivery System, Laser Welding