Initial Clinical Experience with the Coherex FlatStent™ and FlatStent™ EF PFO Closure System for In-tunnel PFO Closure: Results of the Coherex-EU Study

ObjectiveThe Coherex-EU Study evaluated the safety and efficacy of PFO closure utilizing novel in-tunnel PFO closure devices. BackgroundTranscatheter closure of patent foramen ovale (PFO) followed the development of transcatheter closure devices designed to patch atrial septal defects (ASDs). The Coherex FlatStent and FlatStent EF devices were designed specifically to treat PFO anatomy. MethodsA total of 95 patients with a clinical indication for PFO closure were enrolled in a prospective, multicenter first in man study at six clinical sites. Thirty-six patients received the first-generation FlatStent study device, and 57 patients received the second-generation FlatStent EF study device, which was modified based on clinical experience during the first 38 cases. Two patients enrolled to receive the first generation did not receive a device. ResultsAt 6 months post-procedure, 45% (17/38) of the intention-to-treat (ITT) cohort receiving the first-generation FlatStent device had complete closure, 26% (10/38) had a trivial residual shunt, and 29% (11/38) had a moderate to large residual shunt. In the ITT cohort receiving the second-generation FlatStent EF device, 76% (43/57) had complete closure, 12% (7/57) had a trivial shunt, and 12% had a moderate to large shunt. Five major adverse events occurred, all without sequelae. ConclusionThis initial study of the Coherex FlatStent/FlatStent EF PFO Closure System demonstrated the potential for in-tunnel PFO closure. The in-tunnel Coherex FlatStent EF may offer an alternative to septal repair devices for PFO closure in appropriately selected patients; however, further investigation will be necessary to establish the best use of this device. (c) 2012 Wiley Periodicals, Inc.