Patients with patent ductus arteriosus treated with an occlusion device designed for small- to moderate-sized ducts had improved outcomes, according to a study in Catherization and Cardiovascular Interventions.
“This is a big step forward in getting companies to design devices specifically for very small children, which we desperately need in pediatric medicine,” Daniel H. Gruenstein, MD, FSCAI, associate professor of pediatrics, section chief of pediatric cardiology and co-director of the Chicago Pediatric Heart Center at the University of Chicago Medicine, said in a press release.
Smaller device implantation
Researchers implanted an occlusion device (Amplatzer Duct Occluder II, St. Jude Medical) in 192 patients (median age, 2.5 years; 63% female) in the United States between August 2008 and April 2011. Patients had a patent ductus arteriosus less than 5.5 mm in diameter and between 3 mm and 12 mm in length. The device was delivered either through an antegrade (n = 128) or retrograde approach. Follow-up was performed after the procedure, 30 days, 6 months, 12 months and annually up to 5 years.
The primary safety outcomes were device- and/or procedure-related serious adverse events through 6 months. Primary efficacy outcomes included absence of continuous murmur and rate of patent ductus arteriosus closure at 6 months. Both sets of outcomes were compared against performance goals calculated using data from a study evaluating another occlusion device (Amplatzer Duct Occluder, St. Jude Medical) designed for larger patent ductus arteriosus.
The majority of patients (93%) experienced successful implantation of the device. The device was removed from 14 patients (7%) due to subjective assessment of retention discs protrusion (n = 9), significant residual shunt (n = 2), incompatibility with successful placement (n = 2) and descending aorta diameter that did not meet the inclusion criteria (n = 1).
Reduction of radiation exposure
Implantation of the device through the retrograde approach was linked to significant reduction in fluoroscopy time (11.6 ± 6.3 minutes) vs. the antegrade approach (15.2 ± 9.1 minutes; P = .0001).
“Given the increasing efforts to decrease radiation exposure in patients, this unique attribute may be an important consideration when selecting a device for [patent ductus arteriosus] occlusion,” Gruenstein and colleagues wrote.
Both safety (1.6% vs. goal of 5.34%; 95% CI, 0.3-4.6) and efficacy performance goals (98.2% vs. goal of 94.6%; 95% CI, 94.8-99.6) were met.
Many patients had echo gradients across the pulmonary artery (n = 53) or aorta (n = 37) before the device was implanted. After implantation, most patients’ mean aortic gradient (85.8%) remained the same or decreased. Some patients had an increase less than 5 mm Hg (7.4%), an increase between 5 mm Hg and 10 mm Hg (6.2%) or a 10-mm Hg increase (n = 1).
“[These data are] helping to push forward less invasive treatments for our tiniest and most vulnerable patients.” Gruenstein said in the release. “They are the ones who are most at risk and who need a wide range of appropriately sized interventional tools.” – by Darlene Dobkowski
This study was supported by St. Jude Medical. Gruenstein reports serving on an advisory panel and data safety monitoring board and consulting for St. Jude Medical. Please see the full study for a list of the other researchers’ relevant financial disclosures.