Pulmonary hypertension is a rare lung disorder characterized by increased pressure in the pulmonary artery. The pulmonary artery carries oxygen-poor bloodfrom the lower chamber on the right side of the heart (right ventricle) to the lungs where it picks up oxygen.
Pulmonary hypertension is present when the blood pressure in the circulationof the lungs is measured at greater than 25 mm of mercury (Hg) at rest or 30mm Hg during exercise. Pulmonary hypertension can be either primary or secondary:
- Primary Pulmonary hypertension. The cause of pulmonary hypertension is unknown. It is rare, affecting 2 people per million. The illness most often occurs in young adults, especially women.
- Secondary Pulmonary Hypertension. Secondary pulmonary hypertension is increased pressure of the blood vessels of the lungs as a result of other medical conditions.
Regardless of whether pulmonary hypertension is primary or secondary, the disorder results in thickening of the pulmonary arteries and narrowing of theseblood vessels. In response, the right side of the heart works harder to movethe blood through these arteries and it becomes enlarged. Eventually overworking the right side of the heart may lead to right-sided heart failure,resulting in death.
While the cause of primary pulmonary hypertension is uncertain, researchers think that in most people who develop the disease, the blood vessels are sensitive to certain factors that cause them to narrow. Diet suppressants, cocaine, and pregnancy are some of the factors that are thought to trigger constriction or narrowing of the pulmonary artery. In about 6-10% of cases, primary pulmonary hypertension is inherited.
Secondary pulmonary hypertension can be associated with breathing disorders such as emphysema and bronchitis, or diseases such as scleroderma, systemic lupus erythematosus (SLE) or congenital heart disease involving heart valves, and pulmonary thromboembolism.
Symptoms of pulmonary hypertension include shortness of breath with minimal exertion, general fatigue, dizziness, and fainting. Swelling of the ankles, bluish lips and skin, and chest pain are among other symptoms of the disease.
Pulmonary hypertension is rarely detected during routine physical examinations and, therefore, often progresses to later stages before being diagnosed. Inaddition to listening to heart sounds with a stethoscope, physicians also use electrocardiogram, pulmonary function tests, perfusion lung scan, and/or right-heart cardiac catheterization to diagnose pulmonary hypertension.
The aim of treatment for pulmonary hypertension is to treat the underlying cause, if it is known. For example, thromboendarterectomy is a surgical procedure performed to remove a blood clot on the lung that is causing the pulmonaryhypertension. Lung transplants are another surgical treatment.
Some patients are helped by taking medicines that make the work of the hearteasier. Anticoagulants, drugs that thin the blood, decrease the tendency of the blood to clot and allow blood to flow more freely. Diuretics decrease theamount of fluid in the body and reduce the amount of work the heart has to do. Calcium channel blockers relax the smooth muscle in the walls of the heartand blood vessels and improve the ability of the heart to pump blood.
One effective medical treatment that dilates blood vessels and seems to helpprevent blood clots from forming is epoprostenol (prostacyclin). Prostacyclinis given intravenously to improve survival, exercise duration, and well-being. It is sometimes used as a bridge to help people who are waiting for a lungtransplant. In other cases it is used for long-term treatment.
Some people require supplemental oxygen through nasal prongs or a mask if breathing becomes difficult.
Pulmonary hypertension is chronic and incurable with an unpredictable survival rate. Length of survival has been improving, with some patients able to live 15-20 years or longer with the disorder.
Since the cause of primary pulmonary hypertension is still unknown, there isno way to prevent or cure this disease. A change in lifestyle may assist patients with daily activities. For example, relaxation exercises help to reducestress. Good health habits such as a healthy diet, not smoking, and getting plenty of rest should be maintained.