Pulmonary Hypertension
By Bobby Gill
Pulmonary hypertension(PULL-mun-ary HI-per-TEN-shun), or PH, is a rare lung disorder noted by increased pressure in the pulmonary arteries. This pressure generally results from a constriction, or stiffening, of the pulmonary arteries that supply blood to the lungs. PH begins when the very small arteries (pulmonary arteries and capillaries) in your lungs become narrowed, blocked or destroyed. This is a serious illness that becomes progressively worse and is sometimes fatal. PH has occurred in some people who took the diet drugs dexfenfluramine and phentermine. There may not be any symptoms in the early stages of PH. The scientific measure of PH is when the in the circulation of the lungs is measured at greater than 25 mm of mercury (Hg) at rest or 30 mm Hg during exercise. The presence of PH may complicate heart diseases and chronic lung diseases. PH occurs in individuals of all ages, races, and ethnic backgrounds. It is much more common in young adults and occurs approximately twice as much in women as it does in men. Pulmonary venous hypertension (PVH) is caused by diseases of the left side of the heart, such as mitral valve disease or a poorly performing left ventricle. This can cause increased pulmonary artery pressures, but rarely leads to severe PAH.
5 Categories of Pulmonary Hypertension
The World Health Organization (WHO) has categorized pulmonary hypertension can be divided into five categories :
* Pulmonary arterial hypertension (PAH)
The pulmonary artery is the large vessel that carries blood from the heart into the lungs so it can pick up oxygen. Most cases of PH affect this artery and the hundreds of tiny blood vessels that branch off from it. This category includes two types of PH :
* Pulmonary hypertension associated with disorders of the respiratory system
• Emphysema
• Interstitial lung disease
• Sleep apnea
• Chronic exposure to high altitude
* Pulmonary hypertension due to chronic thrombotic or embolic disease
• Blood clots in pulmonary arteries
• Pulmonary embolism (caused by clot, tumor, or foreign matter in the lungs)
• Sickle cell disease
* Pulmonary hypertension due to disorders directly affecting the pulmonary blood vessels
• Inflammatory diseases such as schistosomiasis or sarcoidosis
• Pulmonary capillary disease
PH can also occur as a result of other medical conditions :
- chronic liver disease and liver cirrhosis
- rheumatic disorders such as scleroderma or systemic lupus erythematosus (lupus)
- lung conditions including tumors, emphysema, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis
- Pulmonary hypertension is inherited in a small number of cases
Heart Facts
Heart failure is the most common cause of death in people who have PH. Heart diseases including aortic valve disease, left heart failure, mitral valve disease, and congenital heart disease can also cause pulmonary hypertension. Heart failure is rarely reported on death certificates as the underlying cause because specific instructions on the death certificate state that "cardiac failure" should not be listed as the underlying cause of death. Heart attacks can be undiagnosed due to the most severe symptoms of heart attack having varying degrees of severity. The increased workload of the heart causes thickening and enlargement of the right ventricle, making the heart less able to pump blood through the lungs, causing right heart failure. As the blood flowing through the lungs decreases, the left side of the heart receives less blood. Therefore it becomes harder and harder for the left side of the heart to pump to supply sufficient oxygen to the rest of the body, especially during physical activity. Instead,
the left heart fails to pumps blood efficiently, leading to pooling of blood in the lungs. It relieves pressure on the right side of the heart, but at the cost of lower oxygen levels in blood (hypoxia).
Treatment
Heart-lung transplantation or lung transplantation alone is an option for severely affected patients who are not doing well despite aggressive medical therapy. Heart catheterization, involving long, thin tubes called catheters inserted into the heart and lung vessels may be performed to measure pressures and the flow of blood. The type of treatment is determined by whether the PH is arterial, venous, hypoxic, thromboembolic, or miscellaneous. Standard treatments for hypoxic and miscellaneous varieties of PH have not been established. Treatment varies per individual based on the different underlying causes but generally includes taking medications; making lifestyle and dietary changes; having surgery, if necessary; and seeing your doctor regularly. Treatment choices depend on the severity of pulmonary hypertension, the likelihood of progression, and individual's drug tolerance. Treatment involves diuretics, blood thinners, calcium channel blockers, and using supplemental oxygen to increase blood oxygen levels and lung transplant.
Symptoms
Symptoms may also include :
- shortness of breath with mild exertion - shortness of breath upon exertion is the most common symptom of pulmonary hypertension, and virtually everyone who has the condition develops it.
- fatigue
- chest pain or pressure
- dizzy spells and fainting
- fast heartbeat
- ankle or leg swelling (edema) bloating
The symptoms of pulmonary hypertension may resemble other medical conditions or heart problems. Symptoms of pulmonary hypertension do not usually occur until the condition has progressed and are often the first clue to PH. They range in severity and a given patient may not have all of the symptoms.
Causes
There are many causes of pulmonary hypertension, including :
- HIV infection
- drugs and toxins
- lung disorders
- low blood oxygen levels (hypoxia)
While the cause of primary pulmonary hypertension is uncertain, the general thought is that in most people who develop PH, their blood vessels are sensitive to certain factors that cause them to narrow. Other causes can include :
- losing lung tissue from surgery
- injury
- heart failure
- diseases, such as scleroderma
- obesity, which impairs the ability to breathe
- nerve disorders that involve the muscles used to breathe
- chronic liver diseases
- diet drugs, such as dexfenfluramine-phentermine (fen-phen)
Conclusion
Pulmonary hypertension is a serious type of high involving the arteries connecting the right-side of the heart to your lungs. PH is a disease that causes the arteries of the lungs to constrict leading to right heart failure. Pulmonary hypertension is defined as a mean pulmonary arterial pressure = 25 mm Hg at rest or = 35 mm Hg during exercise. The WHO has classified PH into 5 categories. Pulmonary Hypertension is a serious, rare lung and heart disorder with less than 100,000 patients in the United States. Pulmonary hypertension can irrevocably damage the lungs and cause failure of the right ventricle. PH is frequently misdiagnosed and has often progressed to late stage by the time it is accurately diagnosed. Historically PH has been chronic and incurable with a poor survival rate. The good news is that new treatments are now available which have significantly improved the prognosis. Recent statistics indicate that the length of survival is continuing to improve. Some patients are now able to manage their pulmonary hypertension for 15 to 20 years or longer.
|
