What Causes Pulmonary Hypertension?

While hypertension, or high blood pressure, is a very common condition, pulmonary arterial hypertension (PAH), also known simply as pulmonary hypertension, is quite rare. The condition results in the blood vessels in a patient’s lungs narrowing, leading to progressive damage that slows the blood flow to the lungs, causing blood pressure in the lung arteries to rise. As a result, the heart must work progressively harder to pump blood to the area, eventually causing this vital muscle to weaken and fail.

The Importance of an Early Diagnosis

PAH is a deadly disease, but patients can learn how to manage it effectively if their doctors catch it early. The symptoms of PAH develop slowly and worsen as the disease progresses. People at a high risk of developing PAH should keep an eye out for the following symptoms and schedule an appointment for a cardiology consult as soon as they begin.

Given that most of these symptoms can also indicate other conditions, such as asthma and heart disease, it should come as no surprise that PAH is difficult to diagnose. It’s common for patients to see multiple specialists before all other potential health concerns can be ruled out.

Physiological Changes That Accompany Disease Progression

Researchers have yet to determine exactly what causes PAH, but they do know a lot about how it progresses. The condition is diagnosed when a patient’s average blood pressure leaving the arteries is measured at 25 mmHg or higher. 

Initially, PAH presents as a constriction of the blood vessels in the lungs and a thickening of the blood vessel walls. As the lumen gets smaller, the patient’s pulmonary blood pressure goes up, causing problems with the right ventricle of the heart, which cannot pump blood effectively against such high pressures.

As a patient’s PAH progresses, he or she will become fatigued and start experiencing increasing shortness of breath. Many people also begin to notice heart palpitations and chest pressure during this stage. Though there’s no cure for PAH, the median survival rate for patients who are diagnosed early has risen in recent years from 2.5 years to 10 years, with some patients living as long as two decades with the disease.

Types of PAH

There are four recognized forms of PAH:

  1. Idiopathic
  2. Heritable
  3. Drug-induced
  4. Associative

The majority of PAH cases are idiopathic, meaning they have no identifiable cause. The fact that women are twice as likely to develop idiopathic PAH as men has led some researchers to believe that estrogen and other hormonal changes may play a contributing role, while others think it may be linked to autoimmune problems, which are also more common in women.

Risk Factors for Developing PAH

While doctors have yet to determine the exact causes of PAH, they have figured out some of the factors that place some patients at greater risk of developing this serious disease. Research shows that around six percent of cases are inherited and are currently theorizing that these cases are caused by mutations in the patients’ protein receptors that affect tissue growth. 

Though people with a family history of PAH are at an elevated risk, most experts still believe there must be a major precipitating factor that sets off the chain of events leading to disease progression. The precipitating factor could be drug-induced, as with the use of fen-phen in the 1960s and ’70s. It could also be related to another pre-existing condition like HIV, scleroderma, or congenital heart failure.

Despite the lack of knowledge regarding a definitive underlying cause for PAH, researchers have also identified several other lifestyle factors that could contribute to increasing a patient’s risk. In addition to those already mentioned above, they include:

South Carolina residents who believe they may be at a high risk of developing PAH or other cardiac diseases should schedule appointments with their doctors to discuss options and get a referral to a specialist. All forms of elevated pulmonary blood pressure, even those that are not fatal, can cause complications like blood clots, heart arrhythmias, hemoptysis, right-sided heart enlargement, and pregnancy complications.

How PAH Is Diagnosed

Diagnosing PAH can be a challenge because of the confusion surrounding its origins, so it requires the help of a cardiologist. This expert will perform a physical exam, take a full medical history, and analyze the patient’s current symptoms to rule out other diseases. If there is no clear cause of the patient’s symptoms, he or she may also order additional tests. They may include:

Blood Tests

Blood tests won’t show biomarkers for PAH, but they can help doctors rule out other potential problems. They can also help doctors determine the oxygen level in a patient’s arterial blood.

Doppler Echocardiograms

This test uses sound waves to measure blood flow through the heart valves and evaluate the function of the patient’s right ventricle. A doctor can use the information gained during a doppler echo to calculate the patient’s systolic pulmonary artery pressure.

Chest X-rays

Chest x-rays can show if the patient has an enlarged right ventricle. They can also show enlargement of pulmonary arteries.

Scans for Blood Clots

Chest CT scans, pulmonary angiograms, and ventilation-perfusion scans all look for evidence of blood clots in or around the lungs. These blood clots could contribute to PAH.

Right Heart Catheterization

Heart catheterization measures blood pressure in the pulmonary arteries and the rate at which a patient’s heart can pump blood. It can also identify leaks between the two sides of the heart.

Get Treatment Now

South Carolina residents who believe they may be suffering from PAH or a related heart condition should reach out to a specialist right away. Carolina Cardiology Associates provide a wide range of services, including PAH diagnosis and treatment. They have three offices throughout the state, so the best way to get in touch is to submit an inquiry through the organization’s contact page.

The experienced physicians at Carolina Cardiology Associates are committed to the health of every patient who walks through our doors. We understand the challenges of cardiovascular disease and will work with you to provide treatment, education, and a plan for the future to help you live your healthiest life.