Pulmonary Hypertension

Last updated: April 9, 2026, Pacific Time (PDT)
Disease framework for suspected PH: recognize RV pressure-overload syndromes, confirm with right heart catheterization, assign hemodynamic phenotype, then map the physiology to WHO group and treatment path.
All Clinical suspicion Diagnostics Confirmation / grouping Management Back to Main Page

Disease Pathway

clinical suspicion -> echo/probability -> RHC phenotype -> WHO group -> group-specific therapy
Clinical Suspicion

When should PH enter the problem representation?

  • Unexplained exertional dyspnea, syncope/presyncope, chest pressure, hypoxemia, edema/ascites, elevated JVP, loud P2, RV heave, or worsening exercise tolerance
  • Echo concern: elevated RVSP/PASP, high TR velocity, RV dilation/dysfunction, septal flattening, RA enlargement, or pericardial effusion
  • Risk contexts: connective-tissue disease, portal HTN, HIV, methamphetamine/toxin exposure, congenital shunt, chronic lung disease, OSA/hypoventilation, prior PE/CTEPH risk, HFrEF/HFpEF, valve disease
  • High-risk presentation: syncope, hypotension, rising lactate, hypoxemia, escalating O2, low cardiac index, renal/liver congestion, or severe RV failure
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Diagnostics

Order studies that identify PH, severity, and the WHO group

Core labs
  • BNP / NT-proBNP
  • CMP
  • CBC
  • TSH
  • HIV
  • ANA / connective-tissue disease labs when suspected
Imaging / diagnostics
  • ECG
  • CXR
  • Transthoracic echo
  • V/Q scan for CTEPH screen
  • CT chest / CT pulmonary angiography when indicated
  • PFTs with DLCO
  • Sleep evaluation when suspected
Confirmation
  • Right heart catheterization
  • RAP, PA pressures, mPAP, PAWP, CO / CI
  • Calculate PVR, TPG, DPG
  • Consider saturation run if shunt concern
Open RHC interpretation tool
Severity / follow-up anchors
  • 6-minute walk distance
  • WHO functional class
  • RV size/function
  • RA pressure and cardiac index
  • Natriuretic peptide trend
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Differential Diagnosis

PH is physiology; the disease is the driver

WHO group possibilities
  • Group 1: PAH
  • Group 2: left-heart disease / valve disease
  • Group 3: lung disease or hypoxia
  • Group 4: chronic thromboembolic disease
  • Group 5: multifactorial / unclear mechanisms
Common mimics / overlaps
  • Deconditioning, anemia, obesity, obstructive airway disease
  • HFpEF with exertional filling-pressure rise
  • ILD, emphysema, chronic aspiration, OSA/OHS
  • Acute PE, CTEPH, chronic thromboembolic disease without resting PH
  • High-output states / shunts
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Confirm / Classify

Start with RHC phenotype, then assign the clinical group

  • PH: mPAP > 20 mmHg on right heart catheterization.
  • Pre-capillary PH: mPAP > 20, PAWP 15 or less, PVR > 2 WU. Think group 1, 3, 4, or 5 after clinical grouping.
  • Isolated post-capillary PH: mPAP > 20, PAWP > 15, PVR 2 WU or less. Usually group 2 physiology.
  • Combined post-/pre-capillary PH: mPAP > 20, PAWP > 15, PVR > 2 WU. Left-heart disease with pulmonary vascular remodeling / disproportionate PVR component.
  • Group assignment: requires RHC plus echo, lung evaluation, V/Q imaging, left-heart/valve assessment, and targeted risk-factor testing.
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Management

Select the most likely PH pathway

Working PH group / scenario

Resident Pearls

Bedside Use

  • Do not diagnose PAH from echo alone. Echo estimates probability; RHC classifies hemodynamics.
  • Wedge quality matters. A wrong PAWP can turn group 2 physiology into “PAH” by accident.
  • Always screen for CTEPH when pre-capillary PH is plausible; V/Q is usually the screening test.
  • Avoid reflex fluid boluses in RV failure. Small, reassessed boluses may help selected underfilled patients, but congestion and RV dilation often worsen with volume.
  • PH-specific vasodilators are not generic “PH treatment”; group 2 and group 3 disease can be harmed by unselected vasodilator use.

Sources