Percutaneous pulmonary valve implantation based on rapid prototyping of right ventricular outflow tract and pulmonary trunk from MR data

Purpose: To determine if magnetic resonance (MR) imaging data can be used to create rigid models that are accurate representations of the right ventricular outflow tract (RVOT) and pulmonary trunk anatomy and if such models can be used to refine the selection of patients for percutaneous pulmonary valve implantation (PPVI). Materials and Methods: Institutional review board approval and informed patient consent were obtained. Twelve patients’ MR data were analyzed and elaborated for input into a rapid prototyping (RP) system. RP models were successfully built and presented to two experienced cardiologists, who were retrospectively asked if they would have attempted PPVI. Their responses were compared with the documented decisions and outcomes of PPVI. Results: For four subjects, both cardiologists correctly determined, on the basis of MR image or three-dimensional (3D) RP model findings, that PPVI should not have been attempted. Two patients in whom PPVI was attempted were considered to be unsuitable for the procedure after balloon sizing, and in another two patients, implantation was unsuccessful because of device instability. For the four patients in whom PPVI was suitable and the four in whom it was unsuitable, observers 1 and 2 correctly determined suitability for PPVI in four and two patients, respectively, by using the MR images alone. Both observers correctly determined the suitability of five patients by using the 3D models alone. Conclusion: Using 3D RP models resulted in more accurate selection of patients for PPVI than did using MR images.