Pulmonary HTN Flashcards
What is the definition of of Pulmonary HTN? (4 points)
Mean Pulmonary Artery Pressure (PAP) > 25mmHg (at rest) or >30mmHg (during exercise)
Pre-capillary PHTN: PCWP <15mmHg
Post-capillary PHTN: PCWP >15mmHg (i.e. due to LVF)
How would you classify pulmonary HTN? (5)
Group 1: Pulmonary arterial hypertension (PAH): idiopathic (IPAH) or associated with other conditions (CTD, HIV, Congenital Heart disease), Drug induced, Heritable (e.g. BMPR2)
Group 2: Left heart disease
Group 3: Lung disease / Hypoxia or both
Group 4: Chronic thromboembolic
Group 5: Unclear or multifactorial mechanisms
Pulmonary HTN - history?
P: date of Dx, NYHA class at baseline. Was it diagnosed on RHC?
R: FH (BMPR2 mutation), drugs, diseases causing pHTN
I: 6MWT, PFT, TTE, RHC - had investigations to rule out other underlying conditions?
C: Symptoms of RVF, NYHA
M: LTOT (what type? home (static) or portable concentrator, or cylinders), pulmonary rehab, anticoagulation (warfarin for many with Idiopathic PTHN due to risk of in-situ thrombosis in pulmonary arteries) or targeted treatment (e.g. bosentan, sildenafil, PG analogue…etc), has lung transplantation been discussed?
P: coping with disease? How is patient paying for O2 (is it subsidized - otherwise very expensive)
What is your approach to investigating new, suspected pulmonary HTN based on your clinical examination?
T: ECG (RV strain, hypertrophy, p-pulmonale), CXR, TTE (mPAP 30-40 intermediate probability, >40 likely), RHC always needed to confirm Dx, assess severity, test for vasoreactivity, and assess PCWP + PVR (wood units)
E: investigate for underlying aetiology (ANA, ENA, RhF, Anti-scl70, anti-centromere), type 2 (BNP, left & right catheter), type 3 (spirometry, PFT, HRCT, Sleep study), type 4 (VQ/CTPA), type 5 (HIV serology)
S & C: ABG, 6MWT (NYHA), PFT (DLCO - of <50%, moderate disease), ECG (RV strain/hypertrophy)
What are the pharmacologic options for idiopathic PHTN or CTD related pHTN (i.e. type 1 - PAH) - (6)
Patients with confirmed PAH should be referred to a specialised PH center
Anticoagulation with Warfarin (doubles 3y survival)
High-dose CCB (titrated to diltiazem 480-720mg/d or nifedipine 60-120mg/d) if vasoreactive
ER-antagonist (Bosentan, Ambrisentan) - monitor LFTs
PDE5 inhibitors (Sildenafil, Tadalafil) - improves exercise/functional capacity in RCTs
Prostanoids (Nebulised Iloprost) - antiproliferative, vasodilator. But requires 7/day, so compliance maybe an issue.
sGC stimulator (Riociguat)
What is your approach to managing this patient with pulmonary HTN?
Goal: slow progression, minimise symptoms, prevent complications - TO OPTIMISE MANAGEMENT OF UNDERLYING CONDITIONS.
Confirm Dx: ask previous RHC (PA pressure, PCWP, PVR), TTE (mPAP)
A: review investigation for aetiology (autoimmune profile, HIV, TTE/LHC, HRCT/CTPA), treat underlying aetiology, identify & treat depression
T: Non-pharm
- Educate on prognosis, progression, importance of adherence.
- Life-style changes: smoking cessation, ETOH, diet (e.g. low salt), exercise
- Infection prevention: hygiene, vaccine
- Disease-specific Mx: e.g. fluid restriction for HF
- Pulmonary rehabilitation
- Pulmonary hypertension support groups
- LTOT
T: Pharm
- Disease-specific, warfarin (I & IV), diuretics (decreases preload so improves RVF)
- Surgery
- Consider lung transplant - OS 50% at 5y, indicated in severe PAH or inoperable CTEPH (if medical Mx fails)
- Pulmonary endarterectomy if CTEPH
Ensure follow-up and monitor progress & complications
- Review symptoms, 6MWT, ABG, CXR, TTE. Screen & treat depression…etc.
What are the steps of pharmacological therapy for PAH (type 1)?
Based on WHO functional class (same as NYHA).
In Australia, combination therapy can usually be given only in specialised unit or in trial setting.
Class 1: single agent (PDE-5I, ERA, or sGC agonist) - 2C
Class 2-3: Dual combination oral therapy (typically ERA + PDE-5i) - 2B
Class 4: Parenteral prostanoid-containing combination: IV Epo-prostenol or Inhaled Iloprost if declines IV therapy
FU after 6 weeks to 3 months to monitor for response
When should patients referred for lung transplant in patient with PAH? (4)
WHO functional class 3-4 (despite max med therapy - 2-3 agents)
Rapidly progressive disease (6MWT)
Use of parenteral prostanoid therapy (especially if fails)
PVOD (pulmonary veno-occlusive disease)
What is the prognosis of idiopathic pulmonary HTN? (median survival)
Median survival 2-3 years
Side FX of Bosentan / ERAs?
Derranged LFTs
Teratogen
Male infertility
Sildenafil caution?
Do not use with nitrate as the risk of severe hypotension is high
