When someone is diagnosed with pulmonary hypertension, one of the first questions they may ask is: Is this a lung problem or a heart problem?
The answer is that it can be related to either. Pulmonary hypertension affects the blood vessels that carry blood from the heart to the lungs. However, the underlying cause may be a heart condition, a lung disease, or a problem within the pulmonary blood vessels themselves.
Understanding the difference is important because treatment depends on what is causing the increased pressure.
What Happens in Pulmonary Hypertension?
Pulmonary hypertension means that the blood pressure in the arteries carrying blood from the heart to the lungs is higher than normal.
Normally, the right side of the heart pumps blood through these arteries into the lungs, where it receives oxygen. When pressure in these blood vessels increases, the right side of the heart has to work harder to pump blood.
Over time, this extra strain can weaken the right side of the heart and affect its ability to pump blood effectively.
Although the condition involves the blood vessels of the lungs, it does not necessarily mean that the lungs themselves are diseased.
When Is Pulmonary Hypertension Related to the Heart?
Heart disease is an important cause of pulmonary hypertension, particularly when the left side of the heart is affected.
The left side of the heart receives oxygen-rich blood from the lungs and pumps it to the rest of the body. If it cannot pump or relax properly, pressure can build up in the blood vessels returning blood from the lungs to the heart. This increased pressure can eventually affect the pulmonary arteries.
Some heart conditions associated with pulmonary hypertension include:
- Heart failure, particularly when the left side of the heart is affected
- Problems with the heart valves, especially the mitral valve
- Conditions that affect the heart muscle
- Certain congenital heart conditions
In these situations, pulmonary hypertension develops as a consequence of an underlying heart problem.
When Is Pulmonary Hypertension Related to the Lungs?
Certain lung diseases can also lead to pulmonary hypertension.
The lungs contain a network of blood vessels through which blood travels to receive oxygen. Chronic lung disease or persistently low oxygen levels can cause changes in these blood vessels, increasing resistance to blood flow.
Conditions that may contribute include:
- Chronic obstructive pulmonary disease (COPD)
- Pulmonary fibrosis and other interstitial lung diseases
- Emphysema
- Obstructive sleep apnoea, particularly when associated with significant oxygen deprivation
In these patients, pulmonary hypertension may develop as a complication of the underlying respiratory condition.
Can Pulmonary Hypertension Occur Without an Obvious Heart or Lung Disease?
Yes. Some forms of pulmonary hypertension develop because of changes in the pulmonary arteries themselves, rather than being directly caused by an underlying heart or lung disease.
Pulmonary arterial hypertension is one example. It may occur without an identifiable cause or in association with certain medical conditions.
Pulmonary hypertension can also develop due to chronic blood clots in the pulmonary arteries, which restrict blood flow through the lungs.
This is why identifying the underlying cause is essential before deciding on treatment.
How Do Doctors Find Out Whether the Cause Is the Heart or Lungs?
The symptoms of pulmonary hypertension can be similar regardless of the underlying cause. Breathlessness, fatigue, chest discomfort, dizziness and swelling of the legs may occur in patients with either heart-related or lung-related disease.
Doctors therefore use a combination of clinical assessment and investigations.
Depending on the patient’s symptoms and medical history, investigations may include:
Echocardiography: An ultrasound of the heart that assesses heart structure, function and the likelihood of pulmonary hypertension. It can also identify some underlying heart problems.
Lung function tests: These help identify respiratory conditions such as COPD or pulmonary fibrosis that may contribute to pulmonary hypertension.
Chest imaging: Chest X-rays and CT scans may help identify lung disease, enlargement of heart chambers or other abnormalities.
Oxygen assessment: Oxygen levels may be checked at rest, during activity or during sleep, depending on the clinical situation.
Other investigations: Blood tests, sleep studies or scans to assess blood flow through the pulmonary arteries may be required in selected patients.
Right heart catheterisation: This is the definitive test for confirming pulmonary hypertension. It directly measures pressure within the pulmonary circulation and helps distinguish between different causes.
An echocardiogram may suggest pulmonary hypertension, but it cannot confirm the diagnosis on its own.
Does Treatment Depend on Whether It Is Caused by the Heart or Lungs?
Yes. Treatment is guided by the underlying cause.
If pulmonary hypertension is related to left-sided heart disease, treatment focuses on managing the heart condition. If it develops due to chronic lung disease or low oxygen levels, treatment may involve managing the respiratory disease and addressing oxygen deficiency where appropriate.
Other forms of pulmonary hypertension may require specialised medication or procedures under the care of an experienced team.
It is important not to assume that all patients with pulmonary hypertension need the same medicines. Some treatments used for pulmonary arterial hypertension are not suitable for other forms of the condition and may be harmful if prescribed without establishing the correct diagnosis.
When Should You Seek Medical Assessment?
Persistent or unexplained breathlessness should not be ignored, especially if it is accompanied by unusual tiredness, chest discomfort, dizziness, fainting or swelling of the ankles and legs.
People with existing heart or lung conditions should also seek assessment if their breathing becomes progressively worse or their ability to perform everyday activities declines.
Early identification of pulmonary hypertension and its underlying cause can help guide appropriate treatment and follow-up.
Pulmonary Hypertension Assessment at The Chest Clinic
At The Chest Clinic – Dr. Javed Husain & Associates, based in Karachi, we evaluate patients experiencing persistent breathlessness and other symptoms that may be associated with lung disease or pulmonary hypertension.
Dr. Javed Husain, pulmonologist and critical care consultant, assesses respiratory conditions that may contribute to increased pressure in the pulmonary circulation. When findings suggest a cardiac cause or require specialised evaluation, coordination with the appropriate cardiac specialist is important.
For appointments and information call +923018479066, +923293364949, or email us at connect@thechestclinic.pk