Asymmetric redirection of flow through the heart

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Fluid Dynamics

Background:

• Cardiac development involves looping, creating complex flow paths in the mature heart.
• The topology and functional significance of these flow paths remain largely unexplored.

Purpose of the Study:

• To investigate the asymmetric redirection of blood flow in the adult human heart.
• To explore the functional significance of these flow dynamics.

Main Methods:

• Magnetic resonance velocity mapping was used to visualize blood flow.
• Flow fields were mapped and analyzed in relation to cardiac anatomy.

Main Results:

• Sinuous, chirally asymmetric paths of blood flow were observed throughout the heart.
• Asymmetric atrial filling redirects inflow towards atrioventricular valves.
• Ventricular flow redirection enhances ventriculo-atrial coupling and minimizes energy dissipation.

Conclusions:

• Cardiac looping establishes asymmetric flow patterns with potential fluidic and dynamic advantages.
• Chiral asymmetry may optimize blood flow efficiency and cardiac function, particularly during increased demand.
• These findings suggest a 'morphodynamic' mode of cardiac action during exercise.