Three-Dimensional Printing of Life-Like Models for Simulation and Training of Minimally Invasive Cardiac Surgery

Abstract

Objective: As the use of minimally invasive surgery in cardiothoracic surgery increases, so does the need for simulation and training. We developed a heart model for simulation and training of minimally invasive cardiac surgery, particularly minimally invasive mitral valve repair using our new three-dimensional printing system. Methods: Digital imaging and communication in medicine data from patient computed tomography, three-dimensional computer-aided design, and three-dimensional printing helped create replicas of the heart and thoracic cavity. A polyvinyl alcohol model material with a texture and physical properties similar to those of heart tissue was initially used in mitral valve replicas to simulate surgical procedures. To develop this material, we mechanically investigated the composition of each part of the porcine heart. Results: We investigated the elastic modulus and breaking strength of the porcine heart. Based on investigation results, the cardiac model was set at rupture strength 20 MPa, elastic modulus 0.17 MPa, and moisture content 85%. This provided a biotexture and feeling exactly like a patient heart. Computed tomography scans confirmed that the model shape was nearly the same as that of a human heart. We simulated minimally invasive mitral valve repair, including ring annuloplasty, chordal reconstruction, resection and suture, and edge-to-edge repair. Full surgery simulations using this model used minimally invasive cardiac surgery tools including a robot. Conclusions: This life-like model can be used as a standard simulator to train younger, less experienced surgeons to practice minimally invasive cardiac surgery procedures and may help develop new operative tools.