Pulmonary Hypertension Flashcards
What is pulmonary hypertension?
Mean pulmonary arterial pressure >25mmHg (rest) or >30mmHg (exertion).
What are the causes of pulmonary arterial hypertension?
- INCREASED LA PRESSURE: Mitral stenosis, LVF, diastolic dysfunction
- INCREASED PULMONARY BLOOD FLOW: L>R shunts, high flow states, excess central volume
- INCREASED PULMONARY VASCULAR RESISTANCE:
i) vasoconstriction (low alv O2)
ii) obstruction: PE, primary pulmonary HTN
iii) obliteration: arteritis, emphysema, pulmonary fibrosis.
Treatment options in all patients with PAH?
- Oxygen therapy
- Exercise
- Consider anticoagulation
Advanced therapy in pulmonary hypertension
- Prostanoids
- Endothelin receptor antagonists
- PDE5 inhibitors
- Lung transplantation
What are the classifications of pulmonary artery hypertension?
- Pulmonary arterial HTN
- Pulmonary HTN due to left heart disease
- Pulmonary HTN due to lung disease and/or hypoxia
- Chronic thromboembolic pulmonary HTN
- Pulmonary HTN w/ unclear multifactorial mechanisms
What are the causes of Pulmonary HTN due to left heart disease?
- LA or LV disease/dysfunction
- L valvular heart disease (AS/MS)
What are the causes of pulmonary HTN due to lung disease and/or hypoxia?
- i)Parenchymal lung disease (COPD, fibrosis, CF)
- ii)Chronic alveolar hypoxia (chronic high altitude, alveolar hypoventilation disorders, sleep disordered breathing)
What are the mechanisms of pulmonary HTN?
- Hypoxic vasoconstriction
- Decreased area of pulmonary vascular bed
- Volume and pressure overload
How does chronic hypoxia precipitate PAH?
Chronic hypoxia–> pulmonary vasoconstriction. Acts of
pulmonary artery and SM, e.g.: down regulation of endothelial NO synthase and alteration of voltage gated K+ channels leading to vasoconstriction.
How does decreased area of pulmonary vascular bed precipitate PAH?
Leads to a rise in resting pulmonary arterial pressure.
Causes of decreased pulmonary vascular bed precipitating PAH?
causes: collagen vascular disease, HIV infection, drugs and toxins, thrombotic or embolic disease, inflammatory, pulmonary capillary hemangiomatosis, interstitial fibrosis, CF
What must be excluded in diagnosing idiopathic pulmonary artery HTN?
- left-sided cardiac valvular disease
- myocardial disease
- congenital heart disease
- any clinically significant parenchymal lung disease
- systemic connective-tissue disease
- chronic thromboembolic disease
Epidemiology idiopathic PAH?
- Generally young women (20-40y)
- Generally sporadic
Gene mutation link in familial PAH?
10% cases show familial predisposition: mutations in BMPR2.
Symptoms of PAH?
- Dyspnoea
- Fatigue
- Substernal CP (often pleuritic)
- Syncope
- Symptoms of underlying disease
