Trial Shows PFO Closure Device Does Not Decrease Ischemic, Bleeding Events Compared to Medical Therapy

Results of PC trial presented at TCT 2012

 

November 2, 2012

November 2, 2012 – A clinical trial that compared catheter-based PFO closure using an investigational device found that there was no significant reduction in ischemic and bleeding events compared to standard medical therapy; stroke risk was non-significantly reduced with device therapy. The PC trial was presented at the 24th annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, sponsored by the Cardiovascular Research Foundation (CRF).

A PFO (patent foramen ovale) is a hole between the left and right upper chambers (atria) of the heart that fails to close just after birth. Approximately one in four people grow up with a PFO. In some cases a blood clot may pass through the PFO and can potentially travel to the brain causing an ischemic stroke. It is estimated that PFO rates are three times higher in the population of patients with cryptogenic stroke, or stroke without an overt source.

The PC trial compared the efficacy of the percutaneous closure of a PFO using the Amplatzer PFO occluder with medical treatment in patients with cryptogenic stroke with peripheral embolism. Made of wire mesh, the investigational device is inserted into the PFO through a catheter to seal the passageway between the left and right atria.

Patients were randomized in 29 centers in Europe, Brazil, Canada and Australia. Enrollment of 414 patients was completed in February 2009. The primary endpoint of the trial was a composite of death from any cause, non-fatal stroke, transient ischemic attack (TIA) and peripheral embolism.

For the primary composite endpoint researchers found a relative risk reduction of 37 percent when using the investigational device; this reduction was not statistically significant. Results also indicated no significant reduction in ischemic and bleeding events in patients who underwent PFO closure compared to those who received medical therapy (2.9 percent versus 5.7 percent, HR 0.49, 95 percent CI 0.19 – 1.32, P=0.16). The relative risk reduction of stroke through use of the device was 80 percent with a number needed to treat (NNN) of 40, but this reduction was also not statistically significant.

“Percutaneous PFO closure with the investigational Amplatzer PFO occluder device for secondary prevention of thromboembolism showed no significant reduction in ischemic and bleeding events compared with medical treatment in this trial,“ said study investigator Stephan Windecker, M.D., professor and head of interventional cardiology at the Swiss Cardiovascular Center in Bern. “However, the observed difference in stroke may be clinically relevant if confirmed in further studies."

The trial was funded in part by an unrestricted grant provided by St. Jude Medical Inc. Windecker reported grant support from St. Jude Medical related to research in the field of optical coherence tomography.

For more information: www.crf.org