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Pulmonary Hypertension – Kaele Leonard |
Background
- Symptoms: dyspnea, exertional chest pain, fatigue, edema (legs, abdomen), exertional lightheadedness or syncope, palpitation
- Exam: JVD, increased P2, split S2, RV heave, TR murmur, hepatomegaly, ascites, edema
- Signs of RV failure: low cardiac output (hypotension, renal failure, hepatic congestion), arrhythmias, refractory hypoxemia (R→L shunt), effusions (pericardial > pleural)
- WHO Groups and Causes:
- Pulmonary arterial hypertension (PAH): obliteration of blood vessels in the lung
- Idiopathic, heritable
- Drugs/toxins (methamphetamine)
- Associated with CTD, HIV, portal HTN, congenital heart disease, schistosomiasis
- Pulmonary veno-occlusive disease (PVOD), pulmonary capillary hemangiomatosis
- Left heart disease: back pressure and passive congestion
- HFrEF, HFpEF, valvular disease, LA stiffness
- Chronic lung disease: chronic hypoxemia àchronic pulmonary vasoconstriction
- COPD, ILD, OSA, chronic high-altitude, developmental lung disorders
- Pulmonary artery obstruction and thrombi: obstruction due to chronic clot material
- Chronic thromboembolic pulmonary hypertension (CTEPH)
- Unclear or multifactorial mechanisms
- Hematologic disorders, chronic hemolytic anemia, sarcoidosis, pulmonary Langerhans cell histiocytosis, fibrosing mediastinitis, metabolic disorders
Evaluation
- Consult pulmonary hypertension with any questions or assistance with workup. Below are studies to consider ordering to determine etiology/group of pulmonary hypertension
- Labs: BNP, rheumatologic studies (ANA, RF), HIV
- CXR: increased right heart border, increased PA
- EKG: RVH, RAD
- TTE w/ bubble: RVSP >35-40, RV dilation and dysfunction, RA dilation, septal flattening, pericardial effusion, evaluate for L heart disease and shunt
- PFTs: decreased DLCO in PH, evaluate for parenchymal lung disease
- VQ scan or CTA chest: evaluate for CTEPH
- Pulmonary angiogram (evaluate for surgical candidacy for pulmonary endarterectomy)
- + CT chest: evaluate for parenchymal lung disease
- + ABG: evaluate for hypoxemia or hypercarbia
- + Sleep study: evaluate for OSA
Right heart catheterization (RHC): diagnose PH and determine pre- vs post-capillary
- See RHC section for hemodynamic assessment
- Nitric oxide challenge assess for drug response
- Fluid challenge → assess left heart compliance
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Definitions |
Characteristics |
Causes |
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Pre-capillary PH |
mPAP > 20 mmHg PAWP ≤ 15 mmHg PVR ≥ 3 WU |
Groups 1, 3, 4, 5 |
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Post-capillary PH |
mPAP > 20 mmHg PAWP > 15 mmHg PVR < 3 WU |
Group 2 |
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Combined pre- and post- capillary PH |
mPAP > 20 mmHg PAWP > 15 mmHg PVR ≥ 3 WU |
Group 2, 5 |
Management
- General: treat underlying cause; Diuretics for right heart failure; Oxygen goal SpO2 > 90%
- PAH medicines: Consult pulmonary hypertension for consideration to start or change thes
- Oral treatments may be used as monotherapy or in combination
- Calcium-channel blockers → patients with + vasoreactive challenge
- NO-cGMP enhancers: PDE5-inhibitors sildenafil or tadalafil, riociguat
- Endothelin receptor antagonists (ERAs): bosentan, macitentan, ambrisenta
- Prostacyclins:
- Epoprostenol: IV (Veletri) or inhaled (Flolan), half-life 4 minutes
- Treprostinil: IV/subcutaneous/inhaled/PO, half-life 4 hours
- Iloprost: inhaled, half-life minutes
- Selexipag (Uptravi): PO, half-life hours
- Side effects: headache, jaw pain, flushing, diarrhea, arthralgias
- Oral treatments may be used as monotherapy or in combination
- Treatment based on NYHA functional classification:
- Class I: no treatment or monotherapy
- Class II: monotherapy or combination oral therapy
- Class III: combination oral therapy or prostacyclin
- Class IV: prostacyclin +/- oral therapy
- Lung transplant for patients who are candidates and failing maximal medical therapy
- V-A ECMO can be used as bridge to medical therapy or lung transplant
- Palliative measures
- Atrial septostomy – serves as “pop-off” valve and allows for decompression of failing RV; used as definitive palliative procedure or bridge to lung transplant