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Module 06 · Education only

Provocation & PH

Resting numbers classify pulmonary hypertension; provocation (a vasodilator, exercise, or a fluid bolus) asks whether the pressures are fixed, hidden, or reversible. Four stations, each with the thresholds and the sources behind them. These are teaching tools: no single value here decides therapy or eligibility.

Enter a resting mean PA pressure, the mean wedge (PAWP), and output; read the resistance and gradients; then compare how three generations of definitions label the same numbers.

Resting numbers

Cardiac-cycle mean wedge, not end-diastolic

Only needed for DPG

Classification and PVR use the mean PAWP (averaged over the cardiac cycle, including v waves). The end-diastolic wedge used as an LVEDP surrogate is a different number and is not interchangeable.

Derived

PVR

4.35WU

TPG

20mmHg

DPG

6mmHg

PVR = (mPAP − mean PAWP) / CO
(32 − 12) / 4.6 = 4.35 WU
TPG = mPAP − mean PAWP
32 − 12 = 20 mmHg
DPG = PADP − mean PAWP
18 − 12 = 6 mmHg

Three definitions, one set of numbers

All three definitions agree on this case.

ESC/ERS 2022

mPAP >20 · PAWP 15 · PVR >2 WU

Pre-capillary PH

mPAP >20, PAWP ≤15, PVR >2 WU.

WSPH 2018

mPAP >20 · PAWP 15 · PVR ≥3 WU

Pre-capillary PH

mPAP >20, PAWP ≤15, PVR ≥3 WU.

ESC/ERS 2015

mPAP ≥25 · PAWP 15 · DPG 7 / PVR 3

Pre-capillary PH

mPAP ≥25, PAWP ≤15. PVR ≥3 WU was part of the PAH (group 1) definition, not the pre-capillary definition.

Mean PAWP × PVR plane

Regions follow the 2022 definition; both resistance thresholds are drawn.

Pre-capillaryPAWP ≤15, PVR >2Combined pre- & post-PAWP >15, PVR >2Isolated post-capillaryPAWP >15, PVR ≤2Unclassified / high-flowPAWP ≤15, PVR ≤2gray zone2 WU (ESC/ERS 2022)3 WU (WSPH 2018)PAWP 1505101520253002468Mean PAWP (mmHg)PVR (Wood units)Mean PAWP 12 mmHg, PVR 4.35 WU12, 4.3

Engine findings (pulmonary domain)

The same rule table the calculator uses, filtered to the pulmonary circulation.

  • highPulmonary hypertension by the resting mPAP definitionESC/ERS 2022

    By the 2022 ESC/ERS definition, PH is a resting mean PA pressure above 20 mmHg. The mean wedge pressure and PVR then classify it as pre-capillary, post-capillary, or combined.

  • alertPre-capillary pulmonary hypertensionESC/ERS 2022

    The hemodynamic definition: mPAP above 20, mean PAWP 15 or less, PVR above 2 WU. This describes the pressures and resistance; it does not by itself identify the cause (groups 1, 3, 4, 5 are distinguished clinically).

Education only. These readouts describe a teaching case; they are not advice about any real patient.

What the numbers mean
  • The 2022 ESC/ERS guideline defines PH as a resting mPAP >20 mmHg, pre-capillary PH as mean PAWP ≤15 with PVR >2 WU, isolated post-capillary PH as PAWP >15 with PVR ≤2, and combined pre- and post-capillary PH as PAWP >15 with PVR >2ESC/ERS 2022.
  • The 6th World Symposium (2018) lowered mPAP to >20 but kept PVR ≥3 WU for the pre-capillary component; the 2022 guideline then lowered PVR to >2. Values between 2 and 3 WU are the gray zone where the two labels divergeWSPH 2018ESC/ERS 2022.
  • Before 2018 the threshold was mPAP ≥25 and 21–24 was called borderline; the change was driven by the upper limit of normal (about 20, from a mean of 14 ± 3 in healthy subjects) and by the prognostic weight of mildly raised pressuresKovacs 2009.
  • The 2015 guideline split post-capillary PH with the diastolic pulmonary gradient (DPG ≥7) and/or PVR >3 WU; DPG is noisy, so PVR is now preferredVachiéry 2013.
  • mPAP >20 with PAWP ≤15 and PVR ≤2 is "unclassified": the pressure rise comes from flow (shunt, anemia, cirrhosis, thyrotoxicosis) rather than from resistance or left-sided pressure.
  • A mean PAWP between 15 and 18 mmHg can be "post-capillary" by the PH criteria and still sit below the 18 mmHg "wet" line of the Forrester teaching grid used in the calculator's phenotype. The two frameworks answer different questions (PH classification versus a bedside filling-pressure grid).
  • A low output inflates PVR arithmetically. Check that the CO is credible (thermodilution vs Fick, assumed VO₂) before calling a pre-capillary component.