Results of the U.S. multicenter pivotal study of the HELEX septal occluder for percutaneous closure of secundum atrial septal defects.

Objectives: This study sought to compare the safety and efficacy of the HELEX septal occluder (HSO) with surgical repair of atrial septal defect (ASD).
Background: The HSO is a low-profile, double-disk occluder device for percutaneous closure of secundum ASD.
Methods: Patients were enrolled (HSO arm prospectively, surgery arm prospectively/retrospectively) from 14 U.S. sites and followed up for 12 months postprocedure. Investigator-reported outcomes were evaluated, including closure success (no or clinically insignificant residual shunt) and the incidence of adverse events. The first 3 HSO patients at each site were considered training cases and were excluded from analysis.
Results: Between March 2001 and April 2003, 119 nontraining cases received an HSO and 128 had surgical repair. The groups were similar with statistical but clinically unimportant differences in median age, weight, and preprocedural echocardiographic defect size. Anesthesia time and hospital stay were significantly shorter in the HSO group. Closure success, defined as complete closure or a clinically insignificant residual shunt, was similar in both groups. Major and minor adverse events rates were not statistically different. The most common major adverse events for the HSO group was device embolization requiring catheter retreival (1.7%), and in the surgery group was postpericardiotomy syndrome (6.3%), including one death because of tamponade. The primary end point, clinical success, a composite of closure success and no major adverse events at 12 months, satisfied the noninferiority hypothesis comparing device closure with surgery.
Conclusions: Closure of ASD with the HELEX septal occluder is safe and effective when compared with surgical repair, with reduced anesthesia time and hospital stay. (U.S. Multicenter Pivotal Study of the HELEX Septal Occluder for Percutaneous Closure of Secundum Atrial Septal Defects; this study was approved by the Food and Drug Administration before the National Institutes of Health website was active, so there is not a URL or registration number.).