Analysis of hemodynamic response with 1/R control on biventricular bypass goat.

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Artificial Organs

Background:

• Controlling cardiac output (CO) in total artificial hearts (TAH) is crucial for mimicking natural cardiovascular function.
• Understanding hemodynamic responses of TAH is essential for effective integration with the central nervous system.

Purpose of the Study:

• To develop and evaluate a conductance and arterial pressure-based method (1/R control) for TAH CO regulation.
• To compare the hemodynamic response of 1/R control with the natural heart's function.

Main Methods:

• Implemented biventricular bypass in goats, connecting two pneumatic blood pumps to the natural heart.
• Achieved 100% right heart bypass and 60-90% left heart bypass via pulmonary artery clamping and aortic stenosis.
• Utilized 1/R control, substituting artificial heart output for CO, and monitored pulse rate (PR) and heart rate (HR).

Main Results:

• Demonstrated stable control of TAH cardiac output using the 1/R control method.
• Observed discrepancies in absolute pulse rate (PR) versus heart rate (HR) in the artificial heart.
• Confirmed that relative changes in PR closely mirrored HR changes, indicating duplication of natural cardiac responses.

Conclusions:

• The 1/R control method provides stable and effective regulation of total artificial heart cardiac output.
• This system successfully replicates the relative hemodynamic responses of a natural heart during daily activities.
• 1/R control offers a promising approach for central nervous system integration and control of artificial hearts.