A 3D printed model has been used by UCLA doctors to guide a tricky heart valve replacement before the actual procedure.
Richard Whitaker (66) needed surgery to replace a valve that regulates the blood being pumped from the heart to the lungs. The pulmonary valve is one of the four major valves in the heart and when it doesn’t work effectively this can cause the congestive heart failure symptoms that Whitaker had been experiencing.
Because of previous surgeries and the unique anatomy of his heart, conventional open-heart surgery would have been too risky. So UCLA cardiologists decided to use a less invasive approach to replace the valve.
The team considered the unique structure of the heart and printed a 3D model to practice the surgery before the actual procedure. The key question was whether the replacement valve would align and fit with Whitaker’s unusually large pulmonary arteries.
“We are harnessing the latest technologies like 3D printing to help us better address the most complicated cases,” says Dr Jamil Aboulhosn, Director of the Ahmanson/UCLA Adult Congenital Heart Disease Center and the Streisand/American Heart Association Endowed Chair in the Division of Cardiology at the David Geffen School of Medicine at UCLA.
Materialise, a 3D printing software and service provider, created the 3D model using a CT scan of Whitaker’s heart with a silicon-like material having properties similar to tissues and other structures in the heart. The UCLA team have specified the areas of the model that need to be made from a harder material to simulate calcium deposits, and softer material, to represent heart muscle and vascular tissue.
Aboulhosn has worked on the test run with Dr Daniel Levi, a pediatric cardiologist and director of UCLA’s congenital interventional catheterization laboratory, and Dr Morris Salem of Kaiser Los Angeles. The doctors led a mesh-like stent into place, where it acted as scaffolding to hold the valve, and then channelled the tightly packaged valve into the model. After placing the valve in place, the doctors opened it and found that it was a perfect fit.
Having practiced on the model, doctors performed the real procedure on Whitaker at UCLA. They guided the valve and stent up to the heart through a small vein in the groin using a small tube called a catheter, which is a typical delivery system for this type of minimally invasive procedure. As soon as the valve was placed and deployed, it began to work instantly. Just four days after the procedure, Whitaker was able to go home from the hospital.
“We are very pleased that Richard is doing well,” says Aboulhosn. “With technologies such as 3D printing and advances in minimally invasive procedures, congenital heart patients who might not have survived childhood forty years ago are able to lead full, normal lives today.”
Levi adds that improved technology is making 3D printing an increasingly important tool for doctors and the models created using it are more realistic.