All of us are born with “Pulmonary Hypertension”. The blood pressure in our lungs is the same as our blood pressure in the rest of the body when we are in our mother’s womb and when we are born. As the lungs open up and fill with air the pressure starts to drop from the first breath itself.
When the blood pressure increases here beyond a certain limit (see definition) the condition is called Pulmonary (means lung) hypertension (high blood pressure).
It takes about a week for the lung pressure to come down to half of what it was and a month for it to come down to normal pressures of 25/15 mmHg.
Sometimes this pressure fails to regress in the newborns and is referred to as PPHN (Primary Pulmonary hypertension of the newborn).
Sometimes it never regresses and continues to be high throughout life without any specific cause (called Primary Pulmonary Hypertension) in adulthood.
All of us know the word Hypertension: it means high blood pressure. This refers to the pressure in our whole body except in the lungs. To allow a gentle gas exchange of oxygen and carbon dioxide in the lungs, the lung pressure is approximately 25/15mmHg.
The main problem in Pulmonary Hypertension is that the gas exchange of oxygen does not happen. Carbon dioxide retention is not usually a problem in this condition.
Since the lungs get the blood supply from the heart, when the pressure increases, there is back pressure from the lungs onto the heart and therefore heart is the main organ secondarily affected.
The treatment of Pulmonary Hypertension has advanced a lot but has not reached a point where we can reverse the lung pressure.
Depending on the cause & the course of the disease the treatment may vary. Specific details must be understood from the doctors treating you.