Conditions Pulmonary hypertension

Pulmonary hypertension and the right heart

Raised PA pressure can arise from pulmonary vascular disease (pre-capillary), from left heart disease (post-capillary) or both. The RV response depends on time: an acute load overwhelms a thin RV; chronic load produces hypertrophy and higher pressures at a preserved output.

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

Key measurements

Mean PA pressure

— mmHg

baseline not set

— mmHg

baseline not set

— WU

baseline not set

RV end-diastolic volume

— mL

baseline not set

— L/min

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: pulmonary arteriolar resistance 0.07 → 0.5 mmHg·s/mL; PA compliance 4.0 → 1.5; RV Ees 0.55 → 1.6 and k 0.013 → 0.02 (hypertrophied, stiffer RV); RA stiffness raised. Expected: mPAP > 40 with a normal wedge (pre-capillary pattern), preserved output at rest, raised RAP; contrast with the unadapted acute PE phenotype.

What to look for

Pre-capillary: mPAP > 20, ≤ 15, > 2 WU
Post-capillary: raised with a passive PA rise, ≤ 2 WU
Acute PE: up, output down, PA pressure limited by the unadapted RV

Try it

SVR change%

Mechanism and assumptions

Raises systemic arteriolar resistance, increasing arterial pressure and end-systolic volume; stroke volume falls on the first beat.

Pure arteriolar resistance change; no venous or inotropic effect.
Not a named drug.

Or set a value directly

Pulmonary arteriolar resistancemmHg·s/mL

How this works

Resistance between pulmonary arteries and veins (the model PVR).

Changes: vessels.pa.r

Pulmonary arterial compliancemL/mmHg

How this works

Compliance of the pulmonary arterial compartment; lower compliance raises PA pulse pressure.

Changes: vessels.pa.c

Compare scenariosloads two scenarios side by side

Acute PE vs chronic PH

Same direction of load; the adapted RV generates higher pressure and keeps output.

Pre- vs post-capillary

Similar mPAP can come with a normal or a high wedge; the classification uses PAWP and PVR.

Common misconception. A hemodynamic classification (pre-/post-capillary) does not establish the aetiology of PH or justify a pulmonary vasodilator.

Apply it

mPAP 38, PAWP 22, CO 4 L/min. Classification?

Isolated post-capillary PH (PVR = 4 WU? no: (38−22)/4 = 4 WU → combined)Combined post- and pre-capillary PH: PAWP > 15 and PVR = 4 WU > 2Pre-capillary PH

← Tamponade, constriction and restriction Dilated and hypertrophic failure phenotypes →

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; classification thresholds are versioned content data; no PH aetiology is inferred.
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: pulmonary-hypertension