The present invention is fluorine-containing ethylene copolymer composition and a process of preparing same. The mechanism of delivery can be transcatheter via chambers of the heart, endoscopic pericardial approach via minimally invasive transthoracic access, or intraoperative pericardial approach during open-chest surgery. In the thermal curing device, the tank vessel is heated by a heating unit during rotation, so as to thermally cure the thermosetting resin in the fiber layer and thereby form a fiber-reinforced resin layer. The length of suture can easily be determined with the use of the scale at any point during a surgery. are formed in the outside insulating layer of the insulating layers.