A variable heart rate multi-compartmental coupled model of the cardiovascular and respiratory systems

Figures

• 

  Figure 1.. Schematic of the full cardiovascular system model. The inductances are only present when modelling inertial flows. The diodes represent check valves. Nomenclature is defined in tables 1 and 2.

• 

  Figure 2.. Example pressure–volume diagram for ventricular and septal walls (Vlvf, Vrvf, Vspt) over the cardiac cycle. © 2007 Elsevier Science & Technology Journals, from [22]; permission for use conveyed through Copyright Clearance Center, Inc.

• 

  Figure 3.. Smith non-inertial and inertial CVS model outputs with parameters from tables 3 and 4, providing a like-for-like comparison on the effects of including inertia in the model.

• 

  Figure 4.. Diagram explaining how the left and right ventricles are split into three free wall volumes inside the pericardium. © 2005 Elsevier Science & Technology Journals, from [32]; permission for use conveyed through Copyright Clearance Center, Inc.

• 

  Figure 5.. Plots of Pmus and Valv from the Jallon heart-lung model, which show undesired non-stationary behaviour with Pmus steadily increasing and Valv decreasing. © 2009 The Royal Society (UK), from [18]; permission for use conveyed through Copyright Clearance Center, Inc. (with overlaid red lines to accentuate the drift).

• 

  Figure 6.. Selected outputs from the Jallon heart-lungs model, with parameters from tables 1, 2 and 5. The original behaviour (β = 0) is plotted in blue, with the stabilized model (β = 0.1) overlaid in red. Note the gradual drift in behaviour.

• 

  Figure 7.. Comparison of standard nonlinear and linearized models of ventricular interaction, as components of the Jallon heart-lungs model with parameters from tables 1, 2 and 5 with β = 0.

• 

  Figure 8.. Jallon heart-lungs model outputs with parameters from tables 1, 2 and 5 with β = 0.1. Note the stable behaviour over time.

• 

  Figure 9.. Smith inertial cardiovascular system model outputs with parameters from tables 3 and 4. Variable heart rate simulated with model from §2.4 and equation (3.1).