Defined as a mean pulmonary artery pressure (mPAP) >20 mmHg on right heart catheterization Common TTE findings include:
- Elevated right ventricular systolic pressure (RVSP)
- Right heart dilation or dysfunction
- TR jet velocity >2.8 m/s
- Signs of right heart strain
PH Classification
| Group | Etiology | Examples | Workup | Treatment |
|---|---|---|---|---|
| 1 | PAH | Idiopathic, CTD, HIV, drugs | ANA, HIV, LFTs, RHC (pre-capillary), V/Q scan | ERA, PDE5i, prostacyclins, diuretics, O₂, CCB (if vasoreactive) |
| 2 | Left Heart Disease | HFrEF, HFpEF, valvular disease | TTE, BNP, RHC (post-capillary, wedge >15) | Optimize HF (ACEi/ARB, BB, diuretics), valve repair/replacement |
| 3 | Lung Disease/Hypoxia | COPD, ILD, OSA, altitude | PFTs, Oximetry, ABG, HRCT | Oxygen if hypoxic, treat lung disease; PAH meds usually not indicated |
| 4 | CTEPH | Prior PE, thrombophilia | V/Q scan (sensitive), CT PA, RHC | Anticoagulation, PTE surgery, riociguat or BPA if inoperable |
| 5 | Multifactorial | Sarcoid, sickle cell, CKD | Tailored labs, imaging, biopsies | Treat underlying disease; PAH therapies case-by-case |
TTE Severity Estimation
- Estimated RAP: 3-15mmHg based on IVC diameter and collapsibility: If <2.1cm and >50% collapse = 3mmHg, If >2.1cm or <50% collapse = 8mmHg, if >2.1cm and <50% collapse = 15mmHg
- TR peak velocity: ≥2.8 m/s → Suggests elevated pulmonary pressures
- Estimated RVSP: RVSP ≈ 4 × (TR peak velocity)² + RAP
- PH severity: Mild (35–44 mmHg), moderate (45–59 mmHg), or severe (≥60 mmHg)
RVSP Calculator
If RVSP elevated or etiology unclear, confirm PH with right heart cath
| Severity | mPAP (mmHg) |
|---|---|
| Normal | < 20 |
| Borderline | 20–24 |
| Mild PH | 25–34 |
| Moderate PH | 35–44 |
| Severe PH | ≥ 45 |
- PCWP (wedge pressure)
- ≤15 mmHg = pre-capillary (Groups 1, 3, 4)
- 15 mmHg = post-capillary (Group 2)
- PVR
- ≥3 Wood units + high PAWP = combined pre- and post-capillary (Group 2/5 overlap)
Right Heart Cath PH Calculator
Initial Workup
- Labs: CBC, BMP, LFTs, TSH, HIV, ANA, BNP, troponin
- V/Q scan: rule out CTEPH (Group 4)
- PFTs, Oximetry, HRCT: if ILD or OSA suspected
- Diuresis: ***
- Oxygen goal: >92%
Group 1 (Pulmonary Arterial Hypertension – PAH)
Etiologies: idiopathic, connective tissue disease, HIV, drugs
Treatment:
- PDE-5 inhibitors: sildenafil 20 mg TID, tadalafil 40 mg daily
- Endothelin receptor antagonists: ambrisentan, macitentan
- sGC stimulator: riociguat 1–2.5 mg TID (avoid with PDE5i)
- Prostacyclins: epoprostenol (IV), treprostinil
- Consider vasoreactivity testing → CCBs if positive
- Refer to PH specialty center for advanced therapies