The effect of chordae tendineae on systolic flow

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Computational Fluid Dynamics

Background:

• Simulating ventricular blood flow using Computational Fluid Dynamics (CFD) often neglects sub-valvular structures.
• The impact of the chordae tendineae on intraventricular flow dynamics and pressure dynamics remains incompletely understood.

Purpose of the Study:

• To analyze the influence of the chordae tendineae on fluid flow and pressure drop within the left ventricle during systole.
• To evaluate the validity of commonly used CFD simulation practices that omit these sub-valvular components.

Main Methods:

• Utilized a dynamic 3D computational model of the left ventricle and aorta, derived from real-time three-dimensional echocardiography (RT3DE).
• Incorporated the chordae tendineae as a sub-grid model using the Actuator Line Method, represented by drag coefficients.
• Simulated systolic blood flow dynamics in a model based on a healthy 30-year-old female volunteer.

Main Results:

• The inclusion of chordae tendineae had a minor effect on the overall pressure drop and work efficiency of the left ventricle during systole.
• CFD simulations demonstrated that neglecting chordae tendineae is generally acceptable for predicting bulk systolic ventricular flow and pressure drop.
• Localized flow disturbances, such as vortices behind chordae, were observed but deemed minor for overall hemodynamics.

Conclusions:

• The study supports the current practice of omitting chordae tendineae in CFD simulations of normal systolic ventricular blood flow.
• While bulk flow effects are minor, potential local flow alterations warrant consideration for specific research applications.
• Further evaluation is recommended for cases where localized flow phenomena might be critical.