Calculation of Pulsatile Flow Characteristics in the Mechanical Circulation Assist Device for Fontan Circulation

摘要

We have been developing a pulmonary circulatory assist device using shape memory alloy fibres for Fontan circulation. It consisted of several shape memory alloy fibres, which covered the ePTFE conduit circumferentially. We designed the sequential motion control system for pulsatile flow generation for sophisticated pulmonary hemodynamics. In order to achieve physiological pulsatile flow assistance in pulmonary arterial system, we fabricated a peristaltic mechanical structure by sequential contraction of shape memory alloy fibres. Then, we achieved to generate pulsatile flow by a sequential contraction of the assist system, which could reproduce the wall contrition velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock circulatory system. In this study, we calculated the Womersley numbers by the results derived from the mock experiment. As a result, the pulmonary circulation assist device with the sequential contraction might generate effective pulsatility in pulmonary arterial flow.