Standard medical imaging and new 3D printing technologies are being used to create patient-specific heart valve models that mimic the physiological qualities of the real valves. Their aim is to improve the success rate of transcatheter aortic valve replacements (TAVR) by picking the right prosthetic and avoiding a common complication known as paravalvular leakage.
The researchers found that the models, created from CT scans of the patients’ hearts, behaved so similarly to the real ones that they could reliably predict the leakage. The models are created with a special metamaterial design and then made by a multi-material 3D printer, which gives the researchers control over such design parameters as diameter and curving wavelength of the metamaterial used for printing, to more closely mimic physiological properties of the tissue.
In addition to predicting the occurrence of the leakage, the 3D printed models were also able to replicate the location and severity of the complication during the experiments. Results from their tests showed that the new method using 3D printed valves was a better predictor in certain cases where balloons are used during the procedure to expand the prosthetic valve for a better fit.
The researchers plan to continue to optimize the metamaterial design and 3D printing process and evaluate the use of the 3D printed valves as a pre-surgery planning tool, testing a larger number of patient-specific models and looking for ways to further refine their analytic tools.