pulmonary hypertension Flashcards
3 mechianisms causing PH
- Increased Left Atrium Pressure
- Increased Pulmonary blood flow
- Increased PVR
pathophysiology
• Vasoconstriction
• Vascular remodelling
• In situ thrombosis
Endothelial dysfunction
( decreased NO, decreased prostacyclin,
increased ET-1)
pulmonary vascular resistance
Pah definition
• mPAPr >25 mmHg (rest)
or
• mPAPr >30mmHg (exercise)
plus
- PCWPr <15mmHg
- PVR >240 dynes/sec/cm5
PAH classification
- Pulmonary arterial hypertension (PAH)
1.1. Idiopathic (IPAH)
1.2. Familial (FPAH)
1.3. Associated with (APAH):
1.3.1. Collagen vascular disease
1.3.2. Congenital systemic-to-pulmonary shunts
1.3.3. Portal hypertension
1.3.4. HIV infection
1.3.5. Drugs and toxins (anorexigens)
1.3.6. Other (thyroid disorders, glycogen storage disease, Gaucher
disease, HHT, hemoglobinopathies, myeloproliferative disorders,
splenectomy)
1.4. Associated with significant venous or capillary involvement - PH with left heart disease
- PH associated with lung diseases and/or hypoxemia
- PH due to chronic thrombotic or other embolic disease (CTEPH)
- Miscellaneous
Sarcoidosis, histiocytosis X, lymphangiomatosis, compression of pulmonary
vessels (adenopathy, tumor, fibrosing mediastinitis
symptoms
- Non-specific (frequent delay in diagnosis)
- Breathlessness
- Chestpain
- Syncope
- Fatigue
- Weakness
- Abdominal distension
clinical signs
- RV Heave
- Loud P2
- Murmurs: TR, PR
- RV IIIrd heart sound
- Raised JVP - RV failure
- Hepatomegaly - RV failure
- Oedema, ascites - RV failure
functional classification of PAH modified after th NYHA
Class I: Without resulting limitation of physical activity. Ordinary physical
activity does not cause undue dyspnoea or fatigue, chest pain or near
syncope.
Class II: Slight limitation of physical activity. Comfortable at rest. Ordinary
physical activity causes undue dyspnoea or fatigue, chest pain or near
syncope.
Class III: Marked limitation of physical activity. Comfortable at rest. Less than
ordinary activity causes undue dyspnoea or fatigue, chest pain or near
syncope.
Class IV: Inability to carry out any physical activity without symptoms.
Manifest signs of right heart failure. Dyspnoea and/or fatigue may be present
at rest. Discomfort is increased by any physical activity.
pah investigations
• Spirometry (breathless patient)
• ECG & CXR
– (abnormal in 80-90% of patients with
established PH).
– ECG alone 55% sensitivity, 70% specificity.
• Doppler Echo
– Most useful non-invasive investigation
echocardiography
Estimates PASP
- <37.2 mmHg in 95% normals
- >40 mmHg in 6% >50 yrs old
- >40 mmHg in 5% BMI >30
Excludes significant left heart
disease
bernouilli equation
RVsPr – RAPr = 4VTR
2
sPAPr = 4VTR
2 + RAPr
TR jet velocity:
2.8 – 3.4 m/s = mild PH
confirmation of diagnosis
• Right Heart Catheterisation
– Confirmation of PAH
– Severity assessment
– Shunt estimation (ASD, VSD, PDA)
– Evaluation of left heart disease
– Vasoreactivity testing
(inhaled NO, adenosine)
cteph?
other investigations
• Respiratory
– 6 minute walk test
– ABG on room air
– Lung Function tests
• inc FEV1, FVC, TLC, FRC, TLCO, KCO
• Blood tests
– FBC, U&Es
– Thrombophilia screen in CTEPH
– Thyroid function
– Autoimmune screen
• inc anti-centromere Abs, scl-70,phospholipid Abs, anti-RNP Abs
– Hepatitis serology
– HIV
– Serum ACE
• Urine
- b-HCG in women
classfication of PH
