Conditions Valve lesions

Aortic regurgitation

Diastolic leak from the aorta into the LV. The LV ejects a total that is much larger than the effective forward volume. Acute AR loads a non-adapted LV (high , early mitral closure); chronic AR remodels the LV into a large compliant chamber that keeps filling pressure low until it fails.

Experiment: Normal adult at rest · unchanged from its starting state

Key measurements

Aortic regurgitant fraction

— %

baseline not set

— mL

baseline not set

Forward aortic stroke volume

— mL

baseline not set

Aortic diastolic pressure

— mmHg

baseline not set

— mmHg

baseline not set

Inspect beats and technical detailsbeat selection, transient versus settled, timings

Position within the beat0.000 s

Early beats after a change are transient: the circulation is still re-balancing. A beat is called settled when three consecutive windows agree within the tolerance. Playback speed only moves the cursor over the finished simulation; it never changes the heart rate.

Compare scenariosbaseline, snapshots, axes, export

Baseline

No baseline is set.

Comparison snapshots

Keep up to three snapshots of states you want to compare with the baseline and the current state.

How comparisons are drawn

Side-by-side loops instead of an overlay Identical axes for every loop (turn off and each plot rescales to its own data)

Pressure–volume loop options

Show the ESPVR and EDPVR reference lines Shade stroke work Show the arterial elastance (Ea) line Show the right heart instead of the left

Export

Choose a version

Differences from normal: aortic regurgitant orifice 0 → 0.45 cm² with an unchanged (non-adapted) LV. Expected: large regurgitant fraction, sharply raised LVEDP, early mitral closure pressure crossover, diastolic aortic pressure falls; forward output is reduced because the chamber cannot yet dilate.

What to look for

Aortic diastolic pressure falls toward LV diastolic pressure; wide pulse pressure
No isovolumic relaxation: the LV fills from the aorta while the mitral valve is still closed
Ejected volume ≫ effective forward volume

Try it

Set values directly

Aortic regurgitant orificecm²

How this works

Regurgitant orifice area for the aortic valve. 0 = competent. Not a clinical severity grade.

Changes: valves.av.regurgitantArea

Compare scenariosloads two scenarios side by side

Acute vs chronic AR

Same orifice: the non-adapted LV runs up its EDPVR (high LVEDP, low forward output); the remodelled LV holds a huge volume at low pressure.

Common misconception. can be normal in severe AR because the ventricle ejects a large total ; forward output, not total SV, is what perfuses the body.

Apply it

In chronic AR, slowing the heart rate will:

Increase the regurgitant volume per beat (longer diastole)Reduce the regurgitant volume per beatNot affect regurgitation

← Aortic stenosis Mitral stenosis →

Sources & model detailsreview status, testing, limitations

Sources

Content review

Teaching text and answer keys: Proposed. None of the 2 source claims behind it has been expert reviewed. Where a question has more than one defensible answer, more than one is accepted.

Simulation testing

Finding Hemo closed-loop lumped-parameter model: Quantitatively tested. Software, conservation and qualitative pattern tests pass. Not expert reviewed; normal ranges and phenotype parameter sets are proposed teaching values.
Scenario “Normal adult at rest” is checked for: closed-system volume conservation (<0.1% over 100 beats); timestep sensitivity (<1% change in core stable measurements at dt/2); seeded repeatability; resting pressures, volumes and flows within stated textbook ranges; directional response to fluid bolus and afterload increase.

Passing these tests means the equations are solved correctly and behave as stated. It does not mean the teaching statements, parameter values or answer keys have been expert reviewed.

Limitations that matter here

Quantitative compartment model: regurgitant orifice; remodelling is a fixed parameter set, not a time course.
Reflexes are off: no autonomic compensation follows a change (the optional baroreflex is not enabled).
Constant intrathoracic pressure -3 mmHg (respiratory swing disabled).

Technical details

Model: fh-closed-loop 0.4.0
App / content version: 0.5.0 / 0.5.0
Scenario id: normal-adult
Solver: rk4, dt 0.2 ms
Condition id: aortic-regurgitation