This technology may eliminate need for open heart surgery.
A multi-disciplinary team of Bostonarea researchers from Boston Children’s Hospital, the Wyss Institute for Biologically Inspired Engineering at Harvard University, Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS), and the Karp Lab at Brigham and Women’s Hospital have jointly designed a specialized catheter that, they say, can fix holes in the heart using a biodegradable adhesive and patch. The catheter has been used successfully in animal studies to facilitate hole closure without the need for open heart surgery.
Pedro delNido, MD, chief of cardiac surgery at Boston Children’s, says the device represents a radical change in the way these kinds of cardiac defects are repaired. He explains that “In addition to avoiding open heart surgery, this method avoids suturing into the heart tissue, because we’re just gluing something to it.”
Catheterizations, which are preferable to open heart surgery, don’t require stopping the heart, putting the patient on bypass, and cutting into the heart. This could significantly reduce complications associated with heart defect repair. While medical devices that remain in the body may be jostled out of place or fail to cover the hole as the body grows, the patch allows for heart tissue to create its own closure and then dissolves.
To truly realize the patch’s potential, however, the researchers needed to find a way to deliver the patch without open heart surgery. Their newly designed catheter device utilizes UV light technology and can be used to place the patch in a beating heart.
How It Works
The catheter is inserted through a vein in the neck or groin and directed to the defect within the heart. Once it is in place, the clinician opens two positioning balloons: one around the front end of the catheter, passing through the hole, and one on the other side of the heart wall.
The clinician then deploys the patch and turns on the catheter’s UV light. The light reflects off of the balloon’s shiny interior and activates the patch’s adhesive coating. As the glue cures, pressure from the positioning balloons on either side of the patch help secure it in place. (See Figure 1)
Finally, both balloons are deflated and the catheter is withdrawn. Over time, normal tissue growth resumes and heart tissue grows over the patch. The patch itself dissolves when it is no longer needed.
“This really is a completely new platform for closing wounds or holes anywhere in the body,” said Conor Walsh, PhD, Wyss Institute core faculty member, assistant professor of mechanical and biomedical engineering at SEAS, and founder of the Harvard Biodesign Lab at SEAS. “The device is a minimally invasive way to deliver a patch and then activate it using UV light, all within a matter of five minutes and in an atraumatic way that doesn’t require a separate incision.”
The device is also designed to be customizable. For example, the rate at which the patch biodegrades can be slowed or accelerated depending on how quickly the surrounding tissue grows over it. Further studies will reveal the appropriate lengths of time for different circumstances, the team explained.
Jeff Karp, PhD, a bioengineer at Brigham and Women’s Hospital and a co-founder of Gecko Biomedical, developed the glue product in his lab at Brigham and Women’s. Gecko Biomedical plans to test the glue product in humans later this year.
For more information, visit www.seas.harvard.edu/news .