The Relationship Between Pulmonary Hypertension and Sleep Apnea
Pulmonary hypertension is high blood pressure in the blood vessels of the lungs. Pulmonary hypertension is not a disease by itself, but rather, a result of an underlying condition such as sleep apnea, chronic hypoxemic lung disease, or left heart dysfunction. Pulmonary hypertension is treated by addressing the underlying disorder.
Pulmonary arterial hypertension is a less common form of pulmonary hypertension and is a disease of the pulmonary arteries themselves.
Pulmonary arterial hypertension can lead to right heart failure, and if left untreated, has a poor survival rate. In pulmonary arterial hypertension, the pulmonary arteries that carry blood from the heart to the lungs become too narrow. The exact cause is not entirely known. However, it is known that in people with pulmonary arterial hypertension, the pulmonary arteries constrict and the walls of the vessels begin to remodel. This remodeling makes the vessels thicker, restricting blood flow, and making it more difficult for the heart to pump blood through the pulmonary arteries into the lungs. This results in extra strain on the right side of the heart and over time causes the right side of the heart to become larger and the walls of the heart thicker leading to symptoms of Pulmonary arterial hypertension and ultimately right heart failure. Symptoms of pulmonary arterial hypertension are non-specific and include symptoms such as shortness of breath, fatigue, dizziness, chest pain, and swelling in the ankle and legs. Symptoms are vague and are often similar to other heart or lung conditions that are more common such as asthma and heart disease. This makes diagnosing pulmonary arterial hypertension difficult. Once pulmonary arterial hypertension is suspected, the diagnosis can only be confirmed with a procedure called right heart catheterization. This procedure allows your doctor to directly measure the blood pressure in the pulmonary artery as well as evaluate the severity of pulmonary arterial hypertension and to test the heart function.
Pulmonary hypertension is divided into five groups by the world health organization. Pulmonary arterial hypertension makes up the first group, referred to as WHO Group 1. This group includes idiopathic pulmonary arterial hypertension, inherited pulmonary arterial hypertension, pulmonary arterial hypertension that is associated with risk factors such as various drugs, and those associated with a known underlying disease, often referred to as associated pulmonary arterial hypertension. This includes such conditions as connective tissue diseases, HIV infection, congenital heart disease, chronic hemolytic anemia, schistosomiasis, and portopulmonary hypertension. A second classification system, called the WHO Functional classification, is used to describe disease severity in patients with this disease. This system is used by doctors to monitor disease progression and response to treatment. Prior to 1990, there were very few treatments available for pulmonary arterial hypertension (PAH). Since that time, a number of approved therapies have become available and newer treatments are currently in clinical development. Available treatments for PAH include oral medication, inhaled medication, infused medication, and a combination of these therapies. If an associated disease is involved in the cause of your PAH, it is important that the treatment of this disease is part of your overall PAH care which would possibly involve other specialists such as rheumatologist or gastroenterologist who would be treating the associated condition.
Three pathways have been identified as causing the changes in the pulmonary arteries that lead to PAH.
Treatment for PAH targets the three key pathways. The three major therapeutic classes of PAH treatment are prostacyclins, endothelin receptor antagonists, and phosphodiesterase type five inhibitors. Additional treatment includes diuretics, oxygen when needed, anticoagulants, and the use of calcium channel blockers. In rare cases for select patient with the most severe cases of PAH, lung or heart and lung transplantation is considered.
For PAH patients controlling your intake of salt and foods high in sodium is extremely important. Fluid retention is a common problem for people with PAH. Reducing the amount of salt and foods high in sodium is one way to decrease water buildup. Monitoring fluid intake is another way to avoid swelling and fluid retention. Restricting your fluid intake to 2 L per day is recommended.
Regarding exercise for PAH patients, light resistance training and light to moderate aerobic activities such as walking or swimming may be recommended. People with PAH should not exercise upper and lower limbs at the same time. Patients with severe limitation of activity and history of dizziness or fainting during exercise should not participate in any regular exercise program.
If you think you may have pulmonary arterial hypertension or have been diagnosed with pulmonary arterial hypertension, then referral to a pulmonary arterial hypertension specialist is recommended.
Written by Dr. Nisbet