When you think of blood flow and circulation, the first organ that comes to mind is the heart. But together with your heart, the lungs work to deliver oxygen-rich blood throughout the body. When an obstruction or restriction impedes your body’s ability to carry out this natural process, it forces other areas to go into overdrive in order to compensate.
What is Pulmonary Hypertension?
Pulmonary hypertension (PH) is a type of high blood pressure that affects the right side of the heart as well as the arteries in the lungs. Though it is considered a rare lung disorder, it is the cause for an estimated 200,000 hospitalizations each year in the United States. PH is more common in young adults, and twice as common in women than men, however, the disorder occurs among individuals for all ages, races and ethnic backgrounds.
The World Health Organization (WHO) classifies pulmonary hypertension into five subgroups based on their different causes.
Pulmonary Arterial Hypertension (WHO Group 1)
This refers to pulmonary hypertension caused by narrowing, thickening or stiffness of the arteries in the lungs which forces the right side of the heart to work harder. Within this group there are two types: (1) Idiopathic PAH which has no apparent cause, and (2) Heritable PAH which is linked to hereditary genes passed down from family members.
Pulmonary Hypertension Due to Left Heart Disease (WHO Group 2)
This is the most common form of pulmonary hypertension. Compared to WHO Group 1, the arteries and lungs in this group are not as thick or stiff. But there are problems with how the heart contracts and relaxes, or with the valves on the left side of the heart, leaving the left heart unable to keep up with the returning blood from the lungs.
Pulmonary Hypertension Due to Lung Disease (WHO Group 3)
This group refers to pulmonary hypertension caused by chronic lung disease and/or hypoxia (low oxygen in your organs and tissue); obstructive lung disease such as COPD or emphysema; restrictive lung disease like interstitial lung disease or pulmonary fibrosis; sleep apnea; and living an in area of high altitude for an extended period of time. When the arteries in the lungs tighten, blood flow is restricted to the areas that are receiving the most air and oxygen. The result is high blood pressure throughout the lungs.
Pulmonary Hypertension Due to Chronic Blood Clots in the Lungs (WHO Group 4)
This group is also referred to as chronic thromboembolic pulmonary hypertension (CTEPH), which can occur when the body is unable to dissolve a blood clot in the lungs. This may also lead to scar tissue in the blood vessels, which can limit or block blood flow. Like WHO Group 1, this makes the right side of the heart work harder. Unique to this group, it has the potential to be cured if the blood clots can be successfully removed through pulmonary thromboendarterectomy (PTE) surgery.
Pulmonary Hypertension Due to Unknown Causes (WHO Group 5)
When pulmonary hypertension is present secondary to another disease or condition in ways that are not yet well understood, it is classified as WHO Group 5. Some of these associated conditions include sarcoidosis, sickle cell anemia, chronic hemolytic anemia, splenectomy (spleen removal) and certain metabolic disorders.
What are the symptoms?
The symptoms of pulmonary hypertension often don’t show up until the condition has progressed. The first symptoms to typically appear include:
- Shortness of breath with normal daily activities
- Dizziness and/or fainting spells
- Swelling in the ankles, abdomen or legs
- Bluish lips and skin
- Chest pain
As the condition advances, additional symptoms may be triggered by even minimal activity. These include:
- Irregular heartbeat
- Racing pulse
- Passing out or dizziness
- Progressive shortness of breath
- Difficulty breathing at rest
Keep in mind that not all symptoms will be present for every individual and that their severity may range.
How is it diagnosed?
Because there are so many conditions that may cause pulmonary hypertension, your physician will need to review your symptoms and complete a medical history and physical exam to rule out other diseases or conditions.
During the physical exam, your doctor will listen for abnormal heart sounds, examine the jugular vein in the neck for enlargement, examine your abdomen, legs and ankles for fluid retention and examine your fingernails for bluish tint.
Based on your symptoms additional diagnostics and laboratory tests may be requested to achieve an accurate diagnosis, such as:
- Blood tests
- Doppler echocardiogram
- Chest X-ray
- Pulmonary function tests
- Polysomnogram or overnight oximetry (for sleep apnea)
- Right heart catheterization
- Ventilation perfusion scan
- Pulmonary angiogram
- Chest CT scan
What are the treatment options?
Regardless of which subgroup or type, pulmonary hypertension can lead to right heart failure and death if left untreated.
For those with pulmonary arterial hypertension (WHO Group 1) may benefit from PH-targeted therapies to help relieve symptoms and slow progression. Patients diagnosed with PH due to left heart disease (WHO Group 2) or lung disease (WHO Group 3) may find symptom relief with their underlying condition is treated. And those with chronic blood clots in the lungs (WHO Group 4) can benefit from a surgery to remove the clots. If they are unable to have the surgery or PH remains after the surgery, a PH-targeted therapy may be recommended.
When to See a Physician
If you are experiencing any of the above symptoms of pulmonary hypertension, it is important to consult a physician immediately. I am a pulmonary specialist experienced in treating a variety of lung diseases and breathing-related issues. If you have shortness of breath or any of the other symptoms above, request an appointment today.