Hypertension

1. PULMONARY HYPERTENSION

2. 27 July 2023 2
Introduction
• Generally pulmonary vascular d’ses are:
– Pulmonary oedema
– Pulmonary congestion
– Pulmonary embolism
– Pulmonary infarction
• Specific forms
– Adult respiratory distress syndrome (ARDS)
– Pulmonary hypertension

3. Pulmonary Hypertension and Vascular `
Sclerosis
Classification
Primary or Idiopathic
Secondary

4. Pulmonary circulation
→ low resistance
pulmonary B.P. is 1/8th of systemic
circulation
Pulmonary hypertension → if pulmonary
pressure > ¼ of systemic levels

5. Causes:-
- Chronic Obstructive or Interstitial lung
diseases.
- Emphysema → hypoxia and
destruction of lung parenchyma.
- Chronic Bronchitis
- ,Bronchiectasis
- PTB
- Pneumoconiosis

6. - Antecedent congenital or acquired heart
disease
eg. Mitral stenosis,VSD,ASD
- Reccurent thromboemboli
- Idiopathic

7. Pathogenesis
Secondary forms of pulmonary
hypertension.
Endothelial cells play an important role
Increased shear and mechanical injury
associated with
- Left to right shunts → ASD,VSD
- Biochemical injury produced by fibrin
in thromboembolism.

8. In Primary Pulmonary Hypertension;
Endothelial cell injury is idiopathic
May be associated with
- autoimmune disorders (collagen
diseases)

9. - Toxic substances
- Genetic determinants (family history)
- Decreased prostacylin
- Decreased NO
- Increased endothelin
All these promote pulmonary vasoconstriction

10. - Decreased prostacyclin
- Decreased NO
→ Elaboration promotes platelet
adhesion and activation

11. Endothelial activation
→ endothelial cells thrombogenic
→ promotes the persistence of fibrin
Cytokines
GF → these induce the migration and
replication of vascular smooth muscle cells →
elaboration of extracellular matrix

12. Some patients have vasospastic
component
- Widespread and sustained hypoxic -
vasoconstriction and alveolar
hyperventilation → Pulmonary
hypertension eg high altitude

13. Pathologic obesity (Pickwickian disease)
Upper air way disease eg. Tonsillar
hypertrophy
Neuromascular disease eg. Osteomyelitis
Severe kyphosis

14. Pathologic changes
• May lead to cor-pulmonale
• Pathological changes are seen in Right heart
and pulmonary arterial tree in the lungs
• Right- ventricular hypertrophy
• Right- atrial dilatation

15. Vascular changes
• 1) Arterioles and small pulmonary arteries
Medial hypertrophy
Thickening and redublication of elastic
laminae
Plexiform pulmonary arteriopathy

16. 2) Medium sized pulmonary arteries
concentric intimal thickening
Medial hypertrophy
Adventitial fibrosis
Thickening and redublication of elastic
laminae
3) Large pulmonary arteries
Atheromatous deposits

17. Plants/medicines
- Crotalaria spectabilis (Bush Tea)
- Appetite depressant → aminorex
- Adulterated olive oil

18. - Antiobesity drugs
- Fenfluramine
- Phentermine
These substances may act through
endothelial dysfunction by enhancing
vasoconstriction.