Initial clinical experience with the Coherex FlatStent™ and FlatStent™ EF PFO closure system for in-tunnel PFO closure: results of the Coherex-EU study.

OBJECTIVE: The Coherex-EU Study evaluated the safety and efficacy of PFO closure utilizing novel in-tunnel PFO closure devices. BACKGROUND: Transcatheter 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. METHODS: A 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. RESULTS: At 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. CONCLUSION: This 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.

Transcatheter closure of multiple interatrial communications.

OBJECTIVES: We sought to examine acute and midterm results of closure of multiple interatrial communications with staged device deployment and to review the relevant literature. BACKGROUND: Information about percutaneous methods of closure for multiple defects is limited. METHODS: We treated 148 patients with multiple defects. Of these, 88 had a relevant left to right shunt ("LRS"), 52 had a presumed paradoxical embolism ("PPE"), five had both (LRS and PPE), and one patient, respectively, had migraine, decompression sickness, and a right to left shunt. After implantation of the first device, closure of additional septal defects was attempted only if indicated clinically. RESULTS: Ninety-four patients received a single device and 53 more than one. In four patients, surgical defect closure followed. At the end of follow-up (FU; mean 4.5 ± 3.4 years), complete closure of all defects occurred in 67.6% (62.1% for LRS, 76.5% for PPE). Clinical success (small or trivial residual shunt) was achieved in 86.9% (83.9% for LRS, 90.2% for PPE). Complications included pericardial effusions in 2.7%, recurrent thromboembolic events in 4.8%, and new onset of atrial fibrillation in 10.1%. In a significant number of patients with multiple defects, after single device implantation, the likelihood of complete closure increased with FU time (26% complete closure at 1 month vs. 78% at 24 months). CONCLUSION: Percutaneous closure of multiple interatrial communications is feasible and safe. Importantly, many residual defects close without further intervention at FU. Therefore, staged device delivery is an alternative to simultaneous device implantation, possibly requiring fewer and smaller second devices.

Percutaneous closure of patent foramen ovale with a novel FlatStent.

Patent foramen ovale (PFO) is a congenital, small tunnel-like connection between the right and left atria that usually closes spontaneously after birth. However, frequently (in up to 35% of the normal population) it persists into adulthood. It is associated with 'paradoxical' embolism from the venous to the arterial system and may result in stroke or peripheral embolism. One prophylactic treatment option is transcatheter closure of the PFO. Currently available closure devices extend into both atria and therefore occasionally cause complications, such as thrombus formation or erosion of adjacent structures. The Coherex FlatStent is a flat, self-expanding stent that is designed to be positioned within the PFO tunnel. It is a very small, low-mass device that minimizes the amount of implanted foreign material to reduce the risk of device-related complications. This article focuses on the anatomy of PFOs and compares the Coherex FlatStent with currently available and experimental PFO closure devices.