3D printed medical device. Source: http://www.3ders.org
3D printed medical device. Source: http://www.3ders.org

Researchers at the School of Engineering and Applied Science at Washington University in St. Louis are developing an implantable 3D device that could predict heart attacks.

The biomedical engineers have developed a customized device implant with embedded sensors. The team, led by Igor Efimov, PhD, created the device from a soft, flexible silicon material. The elastic membrane is fitted to precisely fit the patient’s epicardium, which is the outer layer of the wall of the heart.

“Each heart is a different shape, and current devices are one-size-fits-all and don't at all conform to the geometry of a patient's heart,” said Efimov, the Lucy & Stanley Lopata Distinguished Professor of Biomedical Engineering.

“With this application, we image the patient's heart through MRI or CT scan, then computationally extract the image to build a 3D model that we can print on a 3D printer. We then mold the shape of the membrane that will constitute the base of the device deployed on the surface of the heart,” Efimov said.

The device could be used to treat diseases of the ventricles in the lower chamber of the heart or could even be inserted inside the heart to treat disorders such as atrial fibrillation, or heart rhythm disorder.

Tiny sensors can be 3D printed onto the membrane in order to measure temperature, mechanical strains and pH or even deliver a pulse of electricity to treat arrhythmia. These tiny sensors can help physicians determine the overall heart health of the patient and can aid in predicting heart attacks before the patient exhibits physical signs.

“Currently, medical devices to treat heart rhythm diseases are essentially based on two electrodes inserted through the veins and deployed inside the chambers,” says Efimov, “Contact with the tissue is only at one or two points, and it is at a very low resolution. What we want to create is an approach that will allow you to have numerous points of contact and to correct the problem with high-definition diagnostics and high-definition therapy.”

Co-leading the team with Efimov is John Rogers, PhD, the Swanlund Chair and professor of materials science and engineering and director of the F. Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign. Rogers, who developed the transfer printing technique, developed the sensors using semiconductor materials including silicon, gallium arsenide and gallium nitride, along with metals, metal oxides and polymers.

Efimov stated, “In the case of heart rhythm disorders, it could be used to stimulate cardiac muscle or the brain, or in renal disorders, it would monitor ionic concentrations of calcium, potassium and sodium.”

“The membrane could even hold a sensor to measure troponin, a protein expressed in heart cells and a hallmark of a heart attack. Ultimately, such devices will be combined with ventricular assist devices,” Efimov said.

“This is just the beginning,” he continued. “Previous devices have shown huge promise and have saved millions of lives. Now we can take the next step and tackle some arrhythmia issues that we don't know how to treat.”