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arXiv · 2202.01104

Optimal fenestration of the Fontan circulation

Zan Ahmad·Lynn H. Jin·Daniel J. Penny·Craig G. Rusin·Charles S. Peskin·Charles Puelz
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Abstract

In this paper, we develop a pulsatile compartmental model of the Fontan circulation and use it to explore the effects of a fenestration added to this physiology. A fenestration is a shunt between the systemic and pulmonary veins that is added either at the time of Fontan conversion or at a later time for the treatment of complications. This shunt increases cardiac output and decreases systemic venous pressure. However, these hemodynamic benefits are achieved at the expense of a decrease in the arterial oxygen saturation. The model developed this paper incorporates fenestration size as a parameter and describes both blood flow and oxygen transport. It is calibrated to clinical data from Fontan patients, and we use it to study the impact of a fenestration on several hemodynamic variables. In certain scenarios corresponding to high-risk Fontan physiology, we demonstrate the existence of an optimal fenestration size that maximizes oxygen delivery to the systemic tissues.

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Zan Ahmad, Lynn H. Jin, Daniel J. Penny, Craig G. Rusin, Charles S. Peskin, Charles Puelz. 2022-02-02. Optimal fenestration of the Fontan circulation. https://arxiv.org/abs/2202.01104

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