Atrial septal defects (ASD) are one of the most common forms of congenital heart disease. Isolated forms of ASD’s occur in 7% of all congenital heart defects and represent approximately 30-40% of all congenital heart disease in adult patients. Isolated ostium secundum ASD’s can be effectively treated by surgical patch closure or by percutaneous device closure using one of the two currently available devices. If the ASD anatomy is favorable for a device, most cardiac surgeons and cardiologists would agree that percutaneous closure is the preferred method for closure. The currently available devices for percutaneous closure include the Amplatzer Septal Occluder (St. Jude Medical, St. Paul, MN) and the Gore Septal Occluder (Gore Medical, Flagstaff, AZ). Both of these devices work by initially plugging the hold between the two atria by using either Dacron fabric or a Goretex covering. These devices then serve as the scaffolding for eventual tissue overgrowth (endothelialization), which leads to total occlusion often in 6-9 months. Unfortunately, these devices remain within the heart for the rest of the patient’s life and have been shown to suffer malfunctions (wire fractures) or develop severe complications (erosion through the atrial wall into the aorta). The development of a bioabsorbable material that could provide short term occlusion followed by long term ASD closure via endothelialization could revolutionize the method for interventional cardiologists to close ASD’s without the long term concern of fractures or erosion. Investigators in the Department of Biomedical Engineering at the University of Michigan have developed a biocompatible and biodegradable elastomeric polymer material, Poly Glycerol Dodecanoate (PGD). One of PGD’s main properties is shape memory. This property allows it to be formed into a shape that could close ASD’s, and yet allow the device to be stretched into a delivery sheath for percutaneous delivery. Furthermore, the bioabsorbable property allow for the scaffolding material to degrade overtime without leaving behind any significant foreign body material that can lead to later problems. This device could represents a technological breakthrough in the treatment of congenital heart disease.
$426,250 grant from the National Institutes of Health