Migliavacca F, Dubini G, Pietrabissa R, de Leval M R
Dipartimento di Bioingegneria, Politecnico di Milano, Italy.
Med Eng Phys. 1997 Jun;19(4):394-403. doi: 10.1016/s1350-4533(96)00070-7.
The bidirectional cavopulmonary anastomosis is a surgical technique utilized to treat severe congenital malformations of the right part of the heart. It is obtained by anastomosing the superior vena cava to the superior aspect of the undivided right pulmonary artery. Transient simulations with a three-dimensional model of the bidirectional cavopulmonary anastomosis were carried out to evaluate the haemodynamics of different types of pulmonic stenosis (shape and severity of the obstruction). Models with a tunnel-like (supravalvar) or discrete (valvar) pulmonic stenosis with different values of reduction of cross-sectional area (60 and 75%) were investigated and compared to a model without stenosis. Calculations were based on a finite element method analysis. The results showed that a tighter stenosis can lead to a blood volume flow to the left lung reaching 70% of the total pulmonary flow. Moreover, the flow fields are highly influenced by the presence and shape of the pulmonic stenosis; the most intense jets in the left pulmonary artery occur for a discrete pulmonic stenosis of 75%. The flow in the right pulmonary artery is nearly steady because it is damped down by the steady caval flow.
双向腔肺吻合术是一种用于治疗右心严重先天性畸形的外科技术。它通过将上腔静脉与未分隔的右肺动脉的上缘进行吻合来实现。利用双向腔肺吻合术的三维模型进行了瞬态模拟，以评估不同类型肺动脉狭窄（梗阻的形状和严重程度）的血流动力学。研究了具有不同横截面积减小值（60%和75%）的隧道样（瓣上）或离散（瓣膜）肺动脉狭窄模型，并与无狭窄模型进行了比较。计算基于有限元方法分析。结果表明，更严重的狭窄可导致流向左肺的血容量流量达到总肺血流量的70%。此外，流场受肺动脉狭窄的存在和形状的高度影响；左肺动脉中最强烈的射流出现在75%的离散肺动脉狭窄时。右肺动脉中的血流几乎是稳定的，因为它被稳定的腔静脉血流所衰减。
