Assessing Pediatric Pulmonary Artery Pressure And Optimizing Shunt Surgery For Single Ventricle Patients Based On CTA Image

Pulmonary hypertension is a disease with high morbidity and high mortality in infants and young children.The current gold standard for the determination of pulmonary hypertension is the right heart catheterization measurement,but it is an expensive and invasive method that poses a higher risk to pediatric patients.Current clinical non-invasive method is based on Doppler ultrasound estimates of pulmonary artery pressure.Studies have shown that the specificity of estimating the pulmonary artery systolic pressure of patients using Doppler ultrasound is only 56%.Single ventricle is a complex congenital heart disease that results in less blood flow of the pulmonary circulation in children.The first step of the palliative surgery commonly used in clinical treatment of single ventricle is the systemic-to-pulmonary artery shunt surgery.However,due to the individual differences and the variety of bridging vascular protocols,surgical plan relies on the surgeon's experience.Hence,there is a lack of evaluation of the patient's postoperative effect.This article mainly contains three parts.In the first study,we completed diagnosis of pediatric pulmonary hypertension based on Computed Tomography Angiography(CTA).Here were 142 infant data collected from Guangdong General Hospital.The features of the diameter of the main pulmonary artery and the diameter of the ascending aorta were first extracted from CTA imaging,and corrected them.Then according to the relationship between the extracted features and the mean pulmonary arterial pressure,these features were screened and combined.Finally,random forest and support vector machine classifiers were trained according to these features,and the models of screening for severe pulmonary hypertension were obtained separately.The second study was to select the pulmonary hypertension with clear pulmonary and right ventricle images.The right ventricle volume,pulmonary artery volume,pulmonary artery trunk,left and right pulmonary artery crosssectional area,and blood vessel length were extracted from the data.The recursive feature elimination method was used to obtain the optimal combination of features.And multiple linear regression model and multilayer perceptron model were trained to estimate pulmonary artery pressure.The last part of work is the optimization of shunt surgery for single ventricle patients.Firstly,based on the systemic and pulmonary circulatory system unique to a single ventricle,a simplistic lumped parametric model that maximizes the focus on vascularity was constructed.When solving the lumped parametric model component parameters,the centerline was extracted from the CTA image to obtain the vascular resistance,compliance,and blood inertial inertia of the aorta and pulmonary artery.Then the systemic identification was used to solve the peripheral vascular parameters of the systemic circulation.The total lung resistance was used to solve the other parameters of the pulmonary circulation.In this article,using random forest classifier with optimal feature combination,the accuracy of screening for severe pulmonary hypertension was 0.87,the sensitivity was 0.89,the specificity was 0.87 and the AUC was 0.90.Using multiple linear regression with optimal feature combination,The model estimating the root mean square error of the mean pulmonary arterial pressure is approximately 13.26 mm Hg,the adjusted determination coefficient was approximately 0.0316.The error between approximately 57% of the estimated value and the mean pulmonary artery pressure measured by a right heart catheter is less than 10 mm Hg.Research indicated that using CTA imaging to non-invasively screen and diagnose pediatric pulmonary artery pressure in infants and young children is a feasible method.According to the single ventricular lumped parameter model obtained in the article,it was possible to calculate the postoperative index such as shunt rate according to different surgical plans.Therefore,it could provide reference for doctors to determine the most appropriate surgical operation before surgery.