STARFlex Closure of PFO Not Superior to Medical Therapy in Preventing Recurrent Stroke

Chicago—Closure of patent foramen ovale (PFO) is a potentially attractive method of preventing recurrent stroke, but data thus far have been equivocal. A study presented at the AHA meeting suggests that PFO closure using the STARFlex septal repair implantable device (NMT Medical, Boston, MA) is of no benefit in preventing recurrent stroke for the vast majority of patients who have sustained a cryptogenic stroke (stroke of unknown origin).

PFO is estimated to cause up to one third of cryptogenic strokes in patients <60 years of age. The STARFlex septal repair implant is an investigational device comprising 2 umbrella-shaped discs, 1 for each side of the septum. Both the framework and the fabric are made of highly biocompatible material, which is important because the device is a permanent implant. The implant is collapsed into a small catheter through which it is inserted into the heart. It is then opened, with 1 umbrella positioned on each side of the septal defect.

“Percutaneous closure of a PFO with STARFlex plus medical therapy had no advantage over medical therapy alone for the prevention of recurrent stroke or transient ischemic attack in patients under the age of 60 presenting with cryptogenic stroke or transient ischemic attack and PFO,” stated Anthony J. Furlan, MD, University Hospitals Case Medical Center at Case Western Reserve University School of Medicine, Cleveland, Ohio, who presented results at a late-breaking clinical trials session.

CLOSURE I was the first completed, prospective, randomized, independently adjudicated PFO device closure study in stroke patients. STARFlex was not superior to medical therapy in preventing recurrent stroke in patients who had a previous stroke of unknown origin. No significant benefit of STARFlex versus medical therapy was observed related to the degree of initial shunt or in patients with atrial septal aneurysm. An insignificant trend was observed, however, favoring STARFlex over medical therapy for prevention of transient ischemic attack. This requires further study, Dr. Furlan said.

The 2-year stroke rate was similar in the 2 arms (3.1% in the STARFlex group vs 3.4% in the medical therapy group; P=.77). Eighty percent of strokes that occurred over the 2 years of the trial (12 in the STARFlex arm and 13 in the medical therapy arm) were not caused by paradoxical embolism, which would be a reason for PFO closure, Dr. Furlan said.

CLOSURE I was conducted at 87 sites in North America and included 909 patients with a cryptogenic stroke or transient ischemic attack with PFO. Patients were randomized in a 1:1 ratio to receive STARFlex closure of PFO within 30 days, 6 months of aspirin and clopidogrel, followed by 18 months of aspirin versus best medical therapy plus 24 months of warfarin (targeted to an international normalized ratio of 2.5-3.0) or a combination of the 2.

Mean age at baseline was about 46 years. About 52% of study participants were male and about 90% were white. About 73% had an index cryptogenic stroke (the remainder had transient ischemic attack), 58% of the STARFlex group and 51% of the medical therapy group had a moderate/substantial shunt, and 38% and 35%, respectively, had an atrial septal aneurysm ≥10 mm.