3D Printing In Minimally Invasive Surgery For Special Types Of Congenital Ventricular Septal Defects

BackgroundThe 3D printing technology emerged in the 1980 s.And it presently has been gradually applied to the medical field with the development and progress of materials science,medical imaging,and tissue engineering.Minimally invasive cardiac surgery is an emerging treatment in cardiac surgery that can reduce patient injury.But it requires a high level of preoperative cardiac anatomical evaluation.The repair of common membranous ventricular septal defect is technically mature and easy,while special types of ventricular septal defects,including subarterial ventricular septal defect,intracristal ventricular septal defect,subseptal ventricular septal defect,muscular ventricular septal defect,and multiple ventricular septal defects are more challenging to perform via minimally invasive approach because of their complex anatomical location.The 3D printed heart models can copy the anatomic abnormalities of patients’ diseased hearts,and their combination with minimally invasive surgery is an innovation in correction of congenital heart diseases.ObjectiveTo explore the value of 3D printing in performing minimally invasive repair of special types of ventricular septal defects by creating simulated heart models of children with ventricular septal defect based on 3D printing technology,and provide new ideas for minimally invasive cardiac surgery.Methods30 children who underwent surgical treatment in Zhengzhou 7th People’s Hospital from September 2016 to September 2021 and were diagnosed with a special type of ventricular septal defect by ultrasound were selected.Before the operation,they agreed that doctors use 3D printing technology to print out 3D heart models and sign the informed consentand,then preoperative surgical plan design and surgical rehearsal were performed based on the models.The above 30 children were recorded as group A.The group has 19 males and 11 females,aged 52.0±13.4 months and weighing 17.2±4.6 kg.39 children who underwent surgical treatment in the same time and were diagnosed with a special type of ventricular septal defect by ultrasound were selected and recorded as group B,they refused to use 3D printing technology before surgery.The group B has 17 males and 22 females,aged 55.5 ± 15.2 months and weighed 18.4 ± 4.3 kg.In both groups,minimally invasive ventricular septal defect repair were performed under general anesthesia with hypothermic extracorporeal circulation through a right intercostal incision.Their gender,age,weight,operation time,extracorporeal circulation time,intraoperative bleeding,and postoperative ventilator use time were recorded.SPASS 25.0 software was applied,and a t-test was used for statistical methods to compare the differences between the sex,age,weight,operation time,extracorporeal circulation time,intraoperative bleeding,and postoperative ventilator use time of children in groups A and B.ResultsThere was no statistical difference between the two groups in terms of gender,age,weight,and type of actual intraoperative ventricular septal defect（P>0.05）.The accuracy rate of the location and number of ventricular septal defects measured by color Doppler ultrasound（83.3%）was significantly different（P=0.020<0.05）from that of the 3D model（100%）.The difference in operative time was statistically significant（P=0.004<0.05）in group A（132.8±19.9 min）compared to group B（150.8±29.6 min）.The difference in extracorporeal circulation time was statistically significant in group A（55.0±18.1 min）compared to group B（68.0±21.4 min）（P=0.009<0.05）.Intraoperative bleeding volume was statistically significant（P=0.009<0.05）in group A（79.7±24.3ml）compared to group B（105.9±54.1ml）.There was a statistically significant difference in postoperative ventilator use time in group A（222.3±62.1 min）compared to group B（265.1±91.2 min）（P=0.024<0.05）.There were no deaths or surgery-related complications in both groups at follow-up.Conclusions1.The accuracy of measuring the size,location and number of the ventricular septal defect measured by 3D heart models are better than that of general cardiac color Doppler ultrasound.2.3D printing technology combined with minimally invasive ventricular septal defect repair can shorten the operation time,cardiopulmonary bypass time,and postoperative ventilator wearing time and reduce intraoperative blood loss.3.The 3D printed heart model has great teaching significance and accelerates the growth of young doctors.