Volume Assessment of Borderline Double Outlet Right Ventricle with 3D Technology

Masakazu Nakao ¹, Guangyu Zhu ², Munirah Binte Ismail ³, Joon-Hock Yeo ³

¹ Cardiac Surgery, Al Jalila Childrens Specialty Hospital , Dubai, United Arab Emirates; ² School of Energy and Power Engineering, Xi’an Jiaotong University , Xian, China; ³ School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore , Singapore;

Date, time and location: 2018.05.26 17:00, Exhibition area, 1st Floor. Zone – A

Abstract

Background:

Decision for biventricular repair for one dominant ventricle with a contralateral borderline-sized ventricle is a clinical dilemma. With significantly overriding aorta, the

effective ventricular size after septation might lead to the different outcome. We have applied a volume calculation by stereolithography (STL) file to help with the

decision.

Methods:

Only one patient was selected due to limited funding. The baby (weight 2864g) with atrial septal defect, atrioventricular discordance, ventricular septal defect, double outlet right ventricle (DORV), transposition of great arteries, severe subvalvar and valvarpulmonary stenosis, and hypoplastic left pulmonary artery was chosen for the assessment. Computed tomography angiogram was segmented and processed, and STL file was created using Mimics (Materialise, Leuven, Belgium). STL file was then exported to Geomagic Studio (Geomagic Inc., NC) for calculation of right and left ventricle before and after septation. Three patterns of intracardiac baffle were tested and the one with smallest profile was used. 

Results:

The volume of right ventricle (RV) and left ventricle (LV) separated by imaginary straight line between ventricles were 2.328ml and 2.597ml respectively. RV/LV ratio was 0.896. Thereafter, the border was designed to simulate intracardiac baffle to create LV-VSD-aorta passage and the one with lowest profile and natural curve was chosen for the comparison. It showed 1.723ml and 3.202ml for RV and LV respectively. RV/LV ratio was 0.538. She electively underwent patch arterioplasty of main pulmonary artery and left pulmonary artery, right modified Blalock-Taussig shunt with 3.5mm expanded polytetrafluoroethylene graft from right bracheocephalic artery to right pulmonary artery.

Conclusion:

The assessment of borderline ventricular volume using modification by STL file is a useful tool to obtain objective comparison of two ventricles. The assessment of DORV with 3D model has gained its popularity. The volume calculation using the software adds an objective value on clinical decisions.