Risks and Benefits of Using a Commercially Available Ventricular Assist Device for Failing Fontan Cavopulmonary...

Area of Science:

• Cardiovascular Physiology
• Medical Device Engineering

Background:

• Fontan patients often experience circulatory failure due to the absence of a sub-pulmonary ventricle.
• Ventricular assist devices (VADs) are potential solutions but their use in the cavopulmonary pathway is not established.
• Two configurations, Full and Inferior Vena Cava (IVC) support, are considered for cavopulmonary assist.

Purpose of the Study:

• To evaluate the hemodynamic response of failing Fontan physiology to a VAD using numerical modeling.
• To compare the efficacy and safety of Full versus IVC support configurations for cavopulmonary assist.

Main Methods:

• A numerical model of failing Fontan physiology was employed.
• Simulations assessed the hemodynamic effects of a VAD under IVC and Full support scenarios.
• Key hemodynamic parameters including cardiac output and pressures were analyzed.

Main Results:

• Full support improved cardiac output and lowered IVC pressure (<15 mmHg) but risked pulmonary hypertension at higher pump speeds.
• IVC support did not improve hemodynamics and led to unsafe increases in superior vena cava pressure (>20 mmHg).

Conclusions:

• Cavopulmonary VADs, particularly with Full support, may offer benefits for Fontan patients but require careful management to mitigate risks like pulmonary hypertension.
• IVC support configuration is not hemodynamically beneficial and poses significant risks.
• Findings can inform surgical strategies for implementing cavopulmonary VAD support.