3D printer creates transformative device for heart treatment

Professor Igor Efimov at the School of Engineering & Applied Science at Washington University in St Louis and an international team of biomedical engineers and materials scientists have created a 3D elastic membrane made of a soft, flexible silicone material that is precisely shaped to match the heart's epicardium (the outer layer of the wall of the heart). Current technology is two-dimensional and cannot cover the full surface of the epicardium or maintain reliable contact for continual use without sutures or adhesives.

The team subsequently printed tiny sensors onto the membrane that are able to measure temperature, mechanical strain and pH, among other markers, or deliver a pulse of electricity in cases of arrhythmia. These sensors also assist physicians to determine the health of the heart, deliver treatment or predict an impending heart attack before a patient shows any physical signs. Professor Efimov takes up the story:

"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. 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 mould the shape of the membrane that will constitute the base of the device deployed on the surface of the heart.

“Currently, medical devices to treat heart rhythm diseases are essentially based on two electrodes inserted through the veins and deployed inside the chambers. 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 numerous points of contact and one that will correct the problem with high-definition diagnostics and high-definition therapy.

“Because this is implantable, it will allow physicians to monitor vital functions in different organs and intervene when necessary to provide therapy. 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.”

Ultimately, the membrane could be used to treat diseases of the ventricles in the lower chambers of the heart or could be inserted inside the heart to treat a variety of disorders, including atrial fibrillation.

Efimov believes 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.

"This is just the beginning," he adds. "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."