Pulmonary Arterial Hypertension
Hypertension is the condition of having high blood pressure. Pulmonary hypertension is the term used to describe high blood pressure occurring in the arteries of the lungs. One type of pulmonary hypertension is known as pulmonary arterial hypertension (PAH).
The arteries of the lungs carry blood specifically from the heart to the lungs. It is at the site of the lungs where blood becomes oxygenated, which then can be transported to the rest of the body. In the case of PAH, the pulmonary arteries constrict in an abnormal fashion. As a result, the heart has to work faster which then causes the blood pressure within the lungs to increase.
While PAH is a form of pulmonary hypertension, there also exists various types of PAH. As is the case with other types of hypertension, PAH can be caused by various other medical conditions or by taking certain medications. The cause of PAH remains unknown.
PAH is a condition that progresses and worsens over time. It can become life threatening if the pressure rises too high within the pulmonary arteries leading to excess strain on your heart.
Symptoms
There are many symptoms associated with PAH that are similar to that of other cardiorespiratory illnesses, including chest pain, dizziness, fainting, fatigue especially with exercise, edema of the extremities, shortness of breath with activity, and general weakness.
These symptoms are similar to those noted with common diseases such as asthma, pneumonia, chronic obstructive pulmonary disease (COPD), left heart failure and coronary disease. It is no surprise that because all of these illnesses exhibit similar signs and symptoms that doctors might overlook the disorder until the symptoms have progressed to a worsened state.
Diagnosis
Unfortunately, there is no way to diagnose PAH directly. PAH is very rarely diagnosed in its early stages, as most exams appear normal. This is why it is difficult for doctors to diagnose PAH during this time. If your physician does believe you have or at high risk for PAH, they may order a number of tests that would rule out other diseases. These tests include a chest x-ray (of the heart and lungs), electrocardiogram, echocardiogram, pulmonary function tests, perfusion lung scan, an exercise test (typically a six-minute walk test).
Treatment
While there is no cure for PAH, there are various treatment methods. Some options might include medications, surgery and/or lifestyle changes. The main goal of any treatment method for PAH aims to reduce the symptoms experienced, improve the quality of life, and slow the progression of the disease.
Medications are used to reduce the work of the heart by allowing blood to flow more fluidly through the pulmonary arteries. Often, medications are combined to allow for the most beneficial outcome. Some possible medications a doctor might prescribe include endothelin receptor antagonists (ERAs), phosphodiesterase-5 inhibitors (PDEI), prostacyclins, anticoagulants, calcium channel blockers, diuretics, digoxin, and inhaled oxygen.
If your doctor believes that surgery is necessary, there are two surgical treatment options they are possibly considering. The first is a lung or heart0lung transplantation. If no other treatment method works for an individual transplantation may be necessary as a lifesaving procedure. The only drawback is that the supply of donor organs is often very limited. The second surgery is an atrial septostomy. This surgery involves the creation of a hole between the top chambers of the heart, allowing blood to be pumped to the rest of the body without going to the lungs first. While this does reduce the workload placed on the heart it also limits the amount of oxygen that the rest of the body can receive.
Finally, lifestyle changes may be necessary to help reduce symptoms and complications associated with PAH. One of the primary changes that need to be made is limiting activity to decrease likelihood of fatigues, dizziness, shortness of breath, and fainting. Some of these changes might include securing handicapped parking, modifying showers and/or baths, limiting the use of stairs, and altering the organization of the kitchen, laundry room, and other locations of the house for easier access to tools and other daily objects.
Causes
PAH may be caused by various alterations to the muscles of, size within, and debris found in the arteries of the lungs. If the muscles contract the blood is not easily passed through them. Another possibility might be that the walls of the arteries thicken from overgrowth of the lining of the vessels. Finally, blood clots may form in smaller arteries, which could block the flow of blood completely.
With either of these complications the blood flow is restricted which forces the heart to work more than normal to make up for the blockage. At first, the heart muscle will grow slightly, however, it will eventually weaken and may be unable to pump blood efficiently over time. It is when the heart is unable to pump enough blood that patients with PAH experience the symptoms of fatigue, shortness of breath, chest pain, dizziness, and fainting.
Risk Factors
PAH is a condition common in women more so than men. However, no significant difference in occurrence exists with ethnic and racial differences. During delivery and labor women with PAH may experience worse symptoms and this may lead to maternal death. There are certain risk factors that might increase the chance of developing PAH, including use of appetite suppressant drugs, chronic use of cocaine or amphetamines, HIV, liver or connective tissue disease.
Stages
As stated previously, PAH is a progressive disease. There are four states of PAH Class I-IV. Class IV is characterized by no limitation to physical activity. Class II is marked by limitation of some physical activity, however, there is no discomfort while at rest. During this phase light physical activity might cause dizziness or fainting. In Class III individuals experience discomfort only during physical activity, however, it is experienced in even less than ordinary physical activity. In the final Class IV, individuals are unable to perform any physical activity without experiencing discomfort and often present with signs of heart failure in the right ventricle. During this phase patients also have trouble breathing with a worsening of symptoms even while at rest
