Novel Device Demonstrates Promise for Percutaneous PDA Closure in Children

San Francisco, CA—Percutaneous closure of the patent ductus arteriosus (PDA) in children using a novel device is safe and effective, according to a prospective study presented in a featured clinical research session Monday at TCT 2013.

Investigators led by Daniel Gruenstein, MD, of the University of Minnesota enrolled 192 children (mean age, 4.4 years) with a PDA diameter of no more than 5.5 mm and length of 3 mm to 12 mm at 25 sites between August 2008 and April 2011. Most patients (92.7%) were successfully implanted with the Amplatzer Duct Occluder II (ADO II) and will be followed for 5 years. The device is commercially available in some international markets.

The ADO II is a symmetrical, two-disc device made out of a double-weave of nitinol, which allows for delivery through a smaller, more flexible catheter than its predecessor. It is meant for ductal diameters less than 5.5 mm and is deployed via a 4-F to 5-F sheath.

Six-month findings seem encouraging

The mean smallest PDA diameter was 1.96 mm, the mean PDA diameter was 3.08 mm and mean length was 7.59 mm. Mean procedural and fluoroscopy times were “reasonable,” according to Gruenstein (see Figure).

The antegrade, or venous, approach was used in two-thirds of procedures and resulted in significantly longer fluoroscopy time compared with the retrograde, or arterial, approach (15.2 vs. 11.6 minutes; P=.0018).

At 6 months, the primary safety endpoint of serious adverse events (residual shunt requiring closure, device embolization, prolongation of existing hospitalization) was 1.6% (n=3) with a performance goal of 5.34% (P<.0113). There was one instance of residual shunt requiring closure, one occurrence of device embolization and one prolongation of existing hospitalization due to sinus tachycardia.

The primary efficacy endpoint of absence of residual shunting at 6 months met a performance goal of 94.6% (P<.0201) with a complete closure rate of 98.19%.

Device improvements may expand patient population

The smaller diameter, more flexible delivery system and device symmetry of ADO II compared with its predecessor “allow for flexibility in approach and may broaden the potential patient population,” Gruenstein said, adding that the device may also “represent a step toward closing the preemie PDA.”

Additionally, “preliminary evidence suggests that this flexibility in approach may reduce radiation exposure by reduction of fluoroscopy times,” he said.

With regard to approach, “now that we are down to such a small delivery system, there are theoretical advantages to avoiding going through the heart,” Gruenstein observed. “We’re starting to see at least preliminary evidence that the time of the procedure will go down also.”

Panel chair Howard C. Herrmann, MD, of the University of Pennsylvania, said “this is a huge advance for those rare adults we have to close to be able to go retrograde.”

Disclosures:

Gruenstein reports receiving grant/research support from St. Jude Medical.

Herrmann reports receiving grant support from Abbott Vascular, Boston Scientific, Cordis, Edwards Lifesciences, Medtronic CardioVascular, Siemens, St. Jude Medical and W.L. Gore & Associates; consultant fees/honoraria from Microinterventional Devices, Siemens and St. Jude Medical; and holding equity in Microinterventional Devices.