Pulmonary Hypertension (PHT)

PHT can be caused by:

1. HYPOXIA due to a pulmonary disease
   
   • hypoxia causes changes in the endothelial cells of the pulmonary arteries (PA) causing an increase in vascular resistance
   • COPD is the MCC of hypoxic vasoconstriction of the PA
2. VOLUME OVERLOAD due to a decompensated cardiac disorder
   
   • an increase in LA volume (MI, valvular heart disease, CHF) causes an increase in PA pressure
3. IDIOPATHIC dysfunction of the endothelium cells = primary pulmonary HT
   • increase in thickness of the vascular wall (apoptosis dysfunction)
   • decrease in production of prostacyclin and NO 
    

Pulmonary HT can cause RV hypertrophy and because the RV has less compensatory capability, RVF can develop rapidly (cor pulmonale). So you can expect symptoms such as:

• dyspnoea on exertion
• distended neck veins
• chest pain
• increase intensity of P2 and paradoxical splitting of S2
• holosystolic tricuspid insufficiency murmur (due to dilation of the AV ostium) that increases with inspiration (remember the mnemonic: rIght = increase at Inspiration).
• hepatomegaly 
• peripheral edema