Clinical value of patient-specific three-dimensional printing of congenital heart disease: Quantitative and qualitative assessments

Abstract

Objective: Current diagnostic assessment tools remain suboptimal in demonstrating complex morphology of congenital heart disease (CHD). This limitation has posed several challenges in preoperative planning, communication in medical practice, and medical education. This study aims to investigate the dimensional accuracy and the clinical value of 3D printed model of CHD in the above three areas.

Methods: Using cardiac computed tomography angiography (CCTA) data, a patient-specific 3D model of a 20-month-old boy with double outlet right ventricle was printed in Tango Plus material. Pearson correlation coefficient was used to evaluate correlation of the quantitative measurements taken at analogous anatomical locations between the CCTA images pre- and post-3D printing. Qualitative analysis was conducted by distributing surveys to six health professionals (two radiologists, two cardiologists and two cardiac surgeons) and three medical academics to assess the clinical value of the 3D printed model in these three areas.

Results: Excellent correlation (r = 0.99) was noted in the measurements between CCTA and 3D printed model, with a mean difference of 0.23 mm. Four out of six health professionals found the model to be useful in facilitating preoperative planning, while all of them thought that the model would be invaluable in enhancing patient-doctor communication. All three medical academics found the model to be helpful in teaching, and thought that the students will be able to learn the pathology quicker with better understanding.

Conclusion: The complex cardiac anatomy can be accurately replicated in flexible material using 3D printing technology. 3D printed heart models could serve as an excellent tool in facilitating preoperative planning, communication in medical practice, and medical education, although further studies with inclusion of more clinical cases are needed.

Fig 1. Image segmentation using MIMICS Innovation Suite software.

Contrast-enhanced blood and cardiac chambers were highlighted and segmented from the surrounding soft tissue and bony structures.

Fig 2. An example showing how measurements were taken at the aortic arch (top row) and ventricular septal defect (bottom row) using ruler function in Horos.

The left column images refer to contrast-enhanced CT images of the 3D printed model, while the right column images indicate original CCTA images.

Fig 3. Cardiac computed tomography (CT) angiography showing double outlet right ventricle and ventricular septal defect (VSD).

A: 2D axial CT image showing the four-chamber view with sub-aortic VSD (black arrow). B: 2D coronal CT image showing left atrium (LA), right atrium (RA) and left ventricle (LV). C: 2D coronal CT image showing that aorta (AO) and pulmonary artery (black arrows) all arise from right ventricle (RV). IVC-inferior vena cava, white arrow in A refers to ascending aorta.

Fig 4

Labeled screen-display of the virtual model (left) and photograph of the 3D printed heart model (right). Reprinted with permission under the open access from Lau and Sun [31].

Fig 5. Demonstration of the flexibility of the 3D printed heart model in Tango Plus material.

Reprinted with permission under the open access from Lau and Sun [31].

Fig 6. Scatter plot of measurements of 3D printed model against measurements of cardiac computed tomography angiography (CCTA).

Each data point is assigned with a number to represent different anatomical locations. 3D: three-dimensional.

Fig 7. Chart representation of the responses obtained from cardiologists, cardiac surgeons and radiologists.

3D: three-dimensional; DICOM: Digital Imaging and Communications in Medicine.