Prospects of mathematical modelling for optimization of intersystem bypass grafting in congenital heart diseases among children

Abstract

Objective. To study the facilities of mathematical modelling of the system aorta-shunt-pulmonary artery for assessing the efficiency of shunt functioning.
 Materials and methods. The risk factors for the development of complications in 35 newborns and infants of the first year of life were analyzed while carrying out the procedure of the modified Blalock-Taussig shunt (MBTShunt). The study lasted from 2016 to 2021. The age median at the time of operation was 10 (Q1Q3: 3,530) days (from 1 to 180), the body mass median 3,0 (Q1Q3: 2,83,54) kg. The shunt size median was 3,5 mm (Q1Q3: 3,53,5), and the median of shunt size per 1 kg of body mass 1,11 (Q1Q3: 1,01,21) mm/kg.
 The shunt size was increased for 4 out of 35 (11.4%) patients. As a result of cooperation with Perm Polytechnic University, in the frameworks of the program of hydrodynamic modelling evaluation, the data from 4 patients were processed mathematically to assess blood flowing through the MBTShunt.
 Results. Three (9 %) out of thirty five patients died in 3 (Q1Q3: 2,511,0) (minmax 219) days because of cardiorespiratory decompensation. The only prognostically unfavorable risk factor for death was a large value of shunt size to body mass ratio (p=0.023). It was stated according to mathematical modelling data that the blood flow through the pulmonary arteries in all the analyzed types of shunts was not symmetric. An increase in the diameter of a shunt permits to improve a symmetry of blood flow through the left and right branches of the pulmonary artery.
 Conclusions. The procedure of MBTShunt remains the procedure of high risk that is associated with a significant sickness rate and death rate in the early postoperative period. Mathematical modelling of the system aorta-shunt-pulmonary artery prior to the operation makes it possible to choose an optimal diameter of shunt and place of its implantation and will become one of the stages to personified surgery of congenital heart diseases in the future.