Pulmonary hypertension, PH

Pulmonary hypertension (PH) means abnormally increased blood pressure in the pulmonary arteries - the vessels which carry blood from the right side of the heart to the lungs.

It is a serious and in some cases a life-threatening medical condition that damages the right sided heart chambers and ultimately leads to heart failure and inadequate pumping of blood from the heart to the rest of the body. People with pulmonary hypertension may have symptoms of breathlessness, tiredness, dizziness and palpitations.

Mechanism of pulmonary hypertension

The oxygen poor blood is pumped by the right side of the heart towards lungs where blood is enriched by oxygen. Oxygen saturated blood is then pumped by the left side of the heart to the whole body where oxygen is used in muscles and organs.

Under normal circumstances, the demand for oxygen increases during physical exertion, therefore heart rate goes up and pulmonary arteries widen up to allow better blood supply to lungs. In pulmonary hypertension the pulmonary arteries become hard and stiff, unable to allow increased blood flow to lungs. Additionally, pulmonary arteries may be partially or completely blocked by blood clots. As a consequence, the right sided heart chambers have to work harder to push blood through the narrowed pulmonary arteries which may lead gradually to enlargement and weakening of the heart (heart failure) and heart rhythm problems (arrhythmias).

Prevalence of pulmonary hypertension

Pulmonary hypertension is a heterogenous group of different heart and lung conditions. Pulmonary hypertension is commonly diagnosed in the patients with:

  • Chronic obstructive pulmonary disease (COPD)
  • Heart failure due to heart attack (myocardial infarction) or dilated cardiomyopathy (disease of the heart muscle without involvement of coronary arteries)
  • Valve disease, most commonly mitral stenosis, mitral regurgitation and tricuspid regurgitation
  • Pulmonary arterial hypertension (PAH), previously called primary pulmonary hypertension (no other underlying condition, more frequent in women, affects about 2200 people in England and Wales)


The prognosis of pulmonary hypertension depends on the severity of the underlying condition and available treatment options for the primary problem.

In case of pulmonary arterial hypertension, there are many new medicines that improve prognosis and symptoms but it remains a serious condition that usually deteriorates with the passage of time. Sometimes, the diagnosis may get delayed because of nonspecific symptoms on presentation. Progressive breathlessness and tiredness affects day to day life of patients and the treatment should therefore be started as early as possible to control the symptoms and avoid complications.