by John W. Mitchell
, Senior Correspondent | January 05, 2017
Heart surgeons could soon have a new tool in treating patients with aortic stenosis valve disease.
Researchers at Georgia Tech and the Piedmont Heart Hospital have developed a 3-D model designed from detailed CT images that doctors can examine and touch before making the first incision.
Chuck Zhang, Ph.D., a professor at the Georgia Tech School of Industrial and System Engineering got the idea for a 3-D model after a visit by a cardiac imaging specialist and heart surgeon.
"They told us they needed some advanced heart valve phantoms for both patient treatment and research purposes," Zhang told HCB News. "We then started the collaborative project and realized that the 3-D phantoms worked pretty well for many of their patient cases, to predict treatment effectiveness."
According to the American Heart Association, about 5 million people a year are diagnosed with heart valve disease. Aortic stenosis is a condition prevalent in the elderly in which the valves in the left side of the heart narrow. This restricts blood flow, which can lead to heart attack.
The 3-D printed model of a patient’s heart valve would be especially useful in minimally invasive surgery, according to the research team. In this procedure, heart doctors use a catheter to deliver a replacement heart valve. But it is critical to size the replacement valve as accurately as possible.
“The issue is, everybody is different,” said Zhang. “A male will be different than a female. It’s a big challenge for the doctors to select the right type of prosthesis for a specific patient.”
He explained that the 3-D model allows the physician to test how the prosthetic valve will behave. Using the 3-D model, doctors can actually test to see if a particular valve will move and stretch under pressure the same as the patient’s natural heart valve.
It is also possible to adjust physiological specifications in producing the heart valve model. For example, calcium deposits that a patient has present in the valve can be added to the model. This helps the doctors better understand what interventional action will yield the best, safest outcomes.
Zhen Qian, chief of Cardiovascular Imaging Research at Piedmont Heart Institute, which has partnered with Georgia Tech researchers on the project, said the 3-D printed models hold great promise for use in preparing for heart procedures.
“The results are quite encouraging,” Qian said. “Our printed model is able to tell you before the procedure how much paravalvular leakage there will be and where it is, a good indicator for short and long-term mortality.”
Zhang said he thinks that payers will find that the expense of the models is justified.
"Considering the fact that the cost of a 3-D printed model is less than a fraction of the surgery’s cost, it should be pretty easy to make a case to medical professionals and insurance companies to pay for it as part of surgery planning," he said.
Zhang added that he and his team have submitted a joint U.S. provisional patent for the 3-D heart valve model.