ABSTRACT
Devices The original Clamshell double umbrella device,1-3 designed for transcatheter closure of atrial septal defects (ASDs), was subsequently modified and the CardioSEAL (CS) became available.4,5 This device consists of two square-shaped umbrellas connected in the center. The wire skeleton is made of Mp35n, a non-ferromagnetic alloy with a woven Dacron fabric cover. Each arm has three spring coils, which allow variable positions of each arm, rendering the device highly flexible.
