Modelling the heart with the atrioventricular plane as a piston unit

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Computational Biology

Background:

• Medical imaging confirms the heart pumps via minor volume changes and longitudinal movements in the atrioventricular (AV) region.
• Atrioventricular (AV) plane displacement is a reliable index for heart failure diagnosis but is often excluded from cardiovascular models.

Purpose of the Study:

• To develop a lumped-parameter cardiac model that incorporates atrioventricular (AV) plane displacement as a piston unit.
• To investigate the role of AV piston movement in cardiac pumping and its interaction with systolic and diastolic functions.

Main Methods:

• A lumped-parameter cardiac model was created, representing the heart as a displacement pump with an AV piston.
• The AV piston unit was designed with distinct upper and lower areas to mimic atrial and ventricular cross-sections.
• The model's output was validated against normal physiological parameters and movements.

Main Results:

• The model successfully reproduced normal physiological pressures (left ventricular, atrial, arterial) and AV piston movement velocities.
• Simulated systolic ventricular contraction influenced diastolic filling, demonstrating the coupling of cardiac systolic and diastolic functions.
• The model's agreement with normal physiology underscores the importance of myocardial longitudinal movements and atrioventricular interactions.

Conclusions:

• The developed cardiac model effectively simulates cardiac pumping, emphasizing the role of atrioventricular plane displacement.
• Myocardial longitudinal movements and atrioventricular interactions are crucial for effective cardiac function.
• This model provides a valuable tool for understanding cardiovascular dynamics and potentially diagnosing heart failure.