Doctors are not always aware of the specific characteristics of Marfan syndrome that can affect the lungs. Sometimes they focus on the problems in the heart and eyes, not understanding that there can be significant problems in other body systems. Following are some of the key issues involving the lungs in people with Marfan syndrome.
Pectus (chest wall) Deformities
Pneumothorax
Emphysema
Asthma
Sleep Apnea
Q&A Pectus Deformities
Chest wall deformities can restrict lung function. Enlarged air spaces in the lungs and dysfunctional airways can cause respiratory problems. Restrictive lung disease occurs in more than 70 percent of people with Marfan syndrome. Often, this is due to severe pectus abnormalities and/or scoliosis. In either case, the result is that the chest cannot expand fully. The primary symptom is shortness of breath during exertion. While surgery can correct the pectus, there is no evidence that pulmonary function will improve. Scoliosis is typically corrected early, but it can be progressive and cause more problems with pulmonary restriction. Serial pulmonary function tests can determine the progress of the lung restriction. Lung dysfunction can be worse if another airway disease, such as asthma or emphysema, is present. Supplemental oxygen and pulmonary rehabilitation are recommended to improve the quality of life. Pneumothorax
One possible effect of fibrillin-1 deficiency is pneumothorax, in which the lung collapses or detaches from the chest wall. The symptoms of this are shortness of breath, dry cough or an acute onset of pleuritic chest pain (chest pain that gets worse when you take a deep breath). In people with Marfan syndrome pneumothorax can be recurrent, present in both lungs and is frequently associated with early onset emphysema. "Small" pneumothorax is treated in the hospital with supplemental oxygen. “Moderate to large” pneumothorax is treated by chest tube evacuation and possibly pleurodesis (mechanical or chemical pleural "scarring") if necessary. Pneumothorax is common in people with Marfan syndrome. Affected people who require treatment for it should tell the surgeons that they have Marfan syndrome and may need aortic surgery in the future. This will enable the surgeons to make the best treatment recommendation. Emphysema
Emphysema, which results from loss of alveolar walls and enlargement of the air spaces, causes airway obstruction and inflammation. Approximately 10-15 percent of people with Marfan syndrome have emphysema, but it is probably under-diagnosed. It is the structural predisposition of the lungs in people with Marfan syndrome that is probably to blame. Symptoms include shortness of breath during activity, frequent bronchitis (often as a result of common colds or viruses settling in the chest) and low blood oxygen. The diagnosis can be confirmed by a chest x-ray, CT scan, pulmonary function test or arterial blood test. The conventional treatment for emphysema is supplemental oxygen, bronchodilator (which opens up the bronchial tubes) and aggressive treatment of infections. Research is underway on other pharmaceutical agents that may be useful. Asthma
Asthma, which is very common in the general population, is also present in the Marfan community. People with Marfan syndrome who have asthma should see a respiratory specialist who can coordinate care with the other specialists because the conventional treatments for asthma (beta-agonists) have the opposite effect of beta-blockers (which are prescribed to many people with Marfan syndrome). Sleep Apnea
Some people with Marfan syndrome have sleep disordered breathing (sleep apnea), which can have a number of causes. One seems to be laxity of the connective tissues of the airways, which then further relax during sleep and cause partial obstruction to air flow. Often persons with sleep apnea are overweight, but thin persons with Marfan syndrome are also at risk. Any person who snores excessively, sleeps fitfully, seems to have pauses in breathing or gasps for air while sleeping, has a headache on awakening in the morning or regularly falls asleep during the day, should be evaluated by their doctor. Sleep disordered breathing might be the explanation. The potential for lungs problems should offer powerful incentive for people with Marfan syndrome to avoid or quit all forms of smoking. Q & A What are the pulmonary symptoms of Marfan syndrome that doctors unfamiliar with the disorder might miss?Shortness of breath is a common complaint in people with Marfan syndrome. It is important for the doctor to determine which of the following possibilities might explain the shortness of breath in each individual case. - A heart problem, such as a leaky valve
- A lung problem, such as asthma, bullous emphysema or restrictive lung disease
- Being in poor physical shape because of inactivity
Objective tests, such as echocardiograms, can document valve dysfunction, while pulmonary function tests and chest x-rays can reveal lung problems. If the root cause is still unclear, cardiopulmonary exercise testing can be helpful. It is also helpful for the patient to inform the doctor if there is any pattern to the times when coughing or shortness of breath occurs and what makes the symptoms better and worse. Objective information from tests is also needed because symptoms are not usually specific enough. In addition, doctors who are not familiar with Marfan syndrome may not realize that a young person who does not smoke can have emphysema or that a tall, thin person have sleep apnea. However, these diagnoses are quite common in people with Marfan syndrome. Is it possible to confuse lung symptoms of Marfan syndrome with asthma and incorrectly make an asthma diagnosis?
This is often a problem because people who are first diagnosed with Marfan syndrome are frequently children or young adults, an age group in which asthma is a common cause of shortness of breath. In order to make a diagnosis of asthma, a physician may: - Detect wheezing during an episode of shortness of breath that cannot be explained by a cardiac problem or an abnormal chest x-ray.
- Establish a pattern of symptoms that occur following exposure to common asthma triggers, such as smoke or perfume, or following upper respiratory infections.
- Demonstrate an impairment in airflow at baseline or during provocative testing in pulmonary function laboratory (your doctor should know about this testing).
Making the correct diagnosis of asthma or another lung problem is important because the beta blocker medication often prescribed to minimize aortic enlargement in people with Marfan syndrome may complicate asthma treatment or make the asthma worse. If the asthma diagnosis is questionable, other explanations for the shortness of breath should be explored. What are the pulmonary function tests needed to evaluate lung function tests needed to evaluate lung function in people with Marfan syndrome?
In order to rule out asthma, emphysema and restrictive lung disease, people should typically have tests including: routine spirometry with and without medications that open the airways (called bronchodilators), lung volume measurements and a diffusing capacity study. If asthma is a strong possibility, provocative testing should be performed. If there is any evidence of restrictive lung disease, a test of respiratory muscle function should be performed (called maximal inspiratory and expiratory flows). When sleep apnea is a concern, measurement of upper airway resistance during sleep is a required part of any study for a person with Marfan syndrome. (Your doctor can help explain these tests.) What is pulmonary rehabilitation? When might it be helpful?
Pulmonary rehabilitation is a multidisciplinary care program for people with chronic breathing problems. The rehabilitation is individualized to optimize physical and social performance. The goals are typically to reduce symptoms of shortness of breath and increase the ability of the lungs to function properly. Lung tests that measure lung functioning may not change despite an improvement in quality of life.
A typical program usually lasts for 8-12 weeks and should include: exercise training, limb training, inspiratory muscle training, education, nutrition and psychosocial intervention. Throughout the program, there should be assessments of functional capacity and respiratory impairment.
Pulmonary rehabilitation is appropriate for anyone with breathlessness that impacts on quality of life. What is the appropriate management of restrictive lung disease? Is it different for people with Marfan syndrome?
Restrictive lung disease is an inability of the lung to expand adequately in order to take in a full breath. This can be caused by either structural abnormalities of the thoracic cage, such as pectus abnormalities or scoliosis, weak respiratory muscles or lung scarring. For people with Marfan syndrome, the most common causes are chest wall structure or function. Lung scarring is unusual in people with Marfan syndrome. Therefore, the first task for the physician is to determine whether it is a skeletal, muscle or lung problem. This can be accomplished with appropriate pulmonary function testing and a chest CT. Unfortunately, sometimes the degree of restriction does not correlate with the extent of breathlessness or functional impairment. Additionally, apart from early correction of scoliosis, which does improve respiratory function, other surgical measures to normalize the dimensions of the thoracic cage do not always help. Thus, choices about interventions should be individualized to address cosmetic and functional concerns. Is there a recommendation regarding chemical versus mechanical scarring for the treatment of collapsed lungs (spontaneous pneumothorax)?
Physicians who care for people with Marfan syndrome should assume that all patients will eventually require aortic replacement. Therefore, any thoracic procedure should respect the anatomic mandates of future aortic surgery. If supplemental oxygen or chest tube insertion does not successfully treat the pneumothorax, doctors may recommend pleurodesis, which involves "scarring" the lung surface to attach the lung to the chest wall. The best pleurodesis method for individuals with Marfan syndrome is mechanical rather than chemical pleurodesis, as the former makes cardiac surgery easier.
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