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What treatment is available for primary pulmonary hypertension ?

What treatment is available for primary pulmonary hypertension ?

• Diuretics are useful in reducing excessive preload in patients with right heart failure, particularly when hepatic congestion and ascites are present.

• Oral anticoagulants: warfarin is the anticoagulant of choice, in doses adjusted to achieve an INR of
approximately 2.0. Anticoagulants nearly double the 3-year survival rate (Circulation 1984; 70: 580-7).

* Calcium channel blockers: nifedipine, diltiazem. Patients who respond to calcium channel blockers
have a 5-year survival rate of 95% (N Engl J Med 1992; 327: 76-81).

• Intravenous epoprostenol (formerly prostacyclin or prostaglandin I2), which is a potent short-acting
vasodilator and inhibitor of platelet aggregation that is produced by the vascular endothelium (N Engl
J Med 1996; 334: 296-301; N Engl J Med 1998; 338: 273-7).

• Atrial septostomy: the creation of a right-to-left shunt by blade-balloon atrial septostomy has been
reported to improve forward output and alleviate…

What is the prognosis in pulmonary hypertension ?

What is the prognosis in pulmonary hypertension ? 

The prognosis is poor: median survival is approximately 3 years from the time of diagnosis, with about one third of patients surviving for 5 years. 

Death usually occurs suddenly, presumably from arrhythmias or right ventricular infarction.

What are the theories for the cause of primary pulmonary hypertension ?

What are the theories for the cause of primary pulmonary hypertension ? 

• Excess endothelial production of the vasoconstrictor thromboxane relative to dilator prostaglandins such as prostacyclin.

• Excess endothelin-I levels relative to nitric oxide. Inhaled nitric oxide and endothelin-1 antagonists reduce pulmonary hypertension.

• Excessive thrombosis in situ due to increased platelet activation, plasminogen activator inhibitor levels and decreased thrombomodulin.

• Increased serotonin levels.

• Inhibition or downregulation of potassium (Kv) channels in pulmonary artery smooth muscle cells and platelets.

• Activation of elastase and matrix metalloprotease enhances production of mitogens.

• Monoclonal proliferation of endothelial cells.

What are the pathological features of primary pulmonary hypertension ?

What are the pathological features of primary pulmonary hypertension ? 

They are those of plexogenic pulmonary arteriopathy (which also occurs in post-tricuspid left-to-right atrial shunts such as VSD or PDA, and collagen vascular diseases), characterized by medial hypertrophy and concentric intimal fibrosis of the pulmonary arteries with complex plexiform lesions.

Others have no plexiform lesions or concentric intimal fibrosis, but rather have recanalized thrombotic small pulmonary arteries which are said to be the result of small thrombi or recurrent emboli.

The least common histological pattern is veno-occlusive disease.

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