The heart and lungs are frequently affected in people with systemic lupus erythematosus (SLE). Complications in these organs can cause a variety of problems, ranging from mild to serious or even life-threatening. These complications are known as cardiopulmonary (cardio = heart; pulmonary = lung).
It is very important to know the differences between cardiopulmonary complications and non-lupus related problems. The medical examination and laboratory and other tests will help to determine the cause of the problem so appropriate therapy can be used.
Types of Heart or Lung Involvement in Lupus
When investigating a person with cardiopulmonary symptoms, a number of possible causes must be considered. Some problems that can occur in SLE are:
- Pericarditis: inflammation of the lining of the heart
- Myocarditis: inflammation of the tissue of the heart
- Coronary vasculitis: inflammation of blood vessels in the heart
- Pleuritis: inflammation of the sac around the lung
- Pneumonitis: inflammation of the lung
- Pulmonary emboli: blood clots in the lung
Other possible cardiopulmonary problems
Heart and lung problems that are not necessarily lupus-related include:
- Infectious pneumonia: inflammation of the lung due to an infection
- Esophageal spasm: spasm of the section of the digestive tract leading from the mouth to the stomach
- Reflux esophagitis: inflammation of the esophagus due to backflow of contents of the stomach into the esophagus
- Costochondritis: inflammation of the cartilage of the ribs, usually around the breast bone
Cardiac (Heart) Involvement
Lupus can involve all parts of the heart:
- Pericardium: sac surrounding the heart
- Myocardium: muscle layer of the heart
- Endocardium: lining of the inside of the heart
- Coronary arteries that take blood to the heart
Pericarditis, or inflammation of the sac around the heart, is the most common heart involvement in people with lupus. This condition occurs when antigen-antibody complexes-also known as immune complexes-are made during active lupus and cause inflammation within the pericardium.
Symptoms of pericarditis
- Sharp chest pain that can change with changes in the body’s position and frequently may be relieved by leaning forward slightly; this chest pain may feel like a heart attack
- Occasionally, shortness of breath
- In some cases of pericarditis, individuals may not experience physical symptoms.
Pericarditis can occur in conditions other than lupus, therefore the cause must be determined before treatment begins. To help diagnose pericarditis, these tests may be ordered:
- blood tests
- chest x-rays
- electrocardiogram (EKG)
- echocardiogram (ultrasound of the heart) can tell if there is fluid around the heart
- Lupus pericarditis can be treated with anti-inflammatory drugs.
- If anti-inflammatory drug therapy is unsuccessful, a brief course of corticosteroid treatment is usually needed.
- If pericarditis is due to infection or kidney failure, the treatment is different than if it is due to lupus.
When lupus causes inflammation of the tissue of the heart, myocarditis occurs. However, serious heart muscle disease is not common in SLE.
Symptoms of myocarditis
- unexplained rapid heart beat
- irregular heart beat
- abnormal electrocardiogram
- heart failure.
Myocarditis is often seen with inflammation of other muscles in the body, and this condition can lead to tissue damage that replaces heart tissue with scar tissue.
Treatment usually includes corticosteroids such as prednisone. Immunosuppressive drugs such as Cytoxan (cyclophosphamide) and Imuran (azathioprine) may be added if the inflammation is not completely controlled with corticosteroids.
When lupus causes inflammation of the lining of the inside of the heart, endocarditis occurs.
Symptoms of endocarditis
- Although the heart valves can be damaged, this condition rarely affects the pumping efficiency of the heart.
- The surface of the valves can thicken or develop wart-like growths called Libman-Sacks lesions.
- Although these growths may cause heart murmurs, it is uncommon for them to seriously affect the function of the valves.
- However, if bacteria lodge in the growths, infection can occur. This condition is called bacterial endocarditis and can cause scarring of the affected tissue.
- Although also uncommon, bacterial endocarditis is potentially very serious and requires hospitalization.
- The inflammation and scarring of valves rarely leads to a deformity requiring valve replacement.
Coronary artery disease
The coronary arteries deliver blood and oxygen to the heart muscle and are vital to the heart’s pumping function. In people with lupus, these arteries can become prematurely narrowed, causing coronary artery disease.
Studies suggest that people with lupus are more likely to develop premature atherosclerosis if they are on corticosteroids (prednisone) or have kidney involvement.
This blockage can be due to:
- inflammation of the artery wall (arteritis)
- cholesterol deposits inside the wall (atherosclerosis)
- arterial spasm
- blood clot (thrombus)
Symptoms of coronary artery disease
- Narrowing or blockage of an artery can lead to chest pain and a heart attack.
- Atherosclerosis is the most common cause of coronary artery disease in lupus.
In addition, heart damage can develop from inflammation in active lupus or from medications.
Diagnosing coronary artery disease
Early and accurate diagnosis, combined with aggressive therapy to reduce organ damage, is crucial in order to minimize permanent heart damage. Typical tests include:
- chest x-ray
- blood tests to evaluate lupus activity.
Treating coronary artery disease
Treatment of cardiac problems must be individualized for each person and for each problem. However, prevention is the primary treatment of coronary artery disease.
These are three important factors in preventing heart attacks in people with lupus:
- Controlling cardiac risk factors
- Controlling lupus disease activity
- Carefully monitoring corticosteroid use.
Pulmonary (Lung) Involvement
The wide range of pulmonary manifestations (symptoms) associated with lupus needs prompt evaluation and close monitoring.
Diagnostic tools can include:
- chest x-ray
- ventilation-perfusion scan of the lung
- gallium scan
- high-resolution CT scan
- bronchoalveolar lavage
- pulmonary function tests.
While lupus can affect the lungs in many ways, pleuritis (pleurisy) is the most common pulmonary manifestation.
The pleura is a membrane that covers the outside of the lung and the inside of the chest cavity. It produces a small amount of fluid to lubricate the space between the lung and the chest wall. As lupus activity generates immune complexes, they initiate an inflammatory response at this membrane, a condition called pleuritis.
Symptoms of pleuritis
- severe, often sharp, stabbing pain that may be pinpointed to a specific area or areas of the chest.
- sometimes the pain is made worse by taking a deep breath, coughing, sneezing, or laughing.
Sometimes an excessive amount of fluid builds up in the pleural space between the lung and the chest wall. This is called a pleural effusion and occurs less often then pleuritis.
Diagnosing pleural effusion
If the effusion is large enough, it can be seen on a chest x-ray. Since infection or conditions other than lupus can cause pleural effusions, the physician may need to take a sample of the fluid and perform tests to help determine its cause.
Treating pleural effusion
Pleural effusions will usually respond to these medications:
- non-steroidal anti-inflammatory drugs (NSAIDs)
Pleural effusions also may clear by themselves with time.
Pneumonitis is inflammation within the lung tissue. Infection is the most common cause of pneumonitis in people with lupus. Bacteria, virus, or fungi are organisms that can cause infection in the lung. Sometimes pneumonitis may occur without infection and is then called non-infectious pneumonitis.
Symptoms of pneumonitis
- chest pain
- shortness of breath
Since both forms of pneumonitis have the same symptoms, the patient is assumed to have an infection until proven otherwise. The diagnosis of pneumonitis requires:
- blood tests
- sputum (mucus coughed up from the lungs) tests
To determine if infection is the cause of the pneumonitis the physician may also need to perform:
- a bronchoscopy (a visual inspection of the inside of the lungs)
- a lung biopsy (examination of a tissue sample).
Treatment initially includes a course of antibiotics. If laboratory and other diagnostic tests show no proof of infection, then the diagnosis is likely lupus pneumonitis.
This non-infectious pneumonitis is treated with high doses of corticosteroids. Immunosuppressive drugs such as Imuran (azathioprine) may be added if the inflammation is not controlled with corticosteroids.
Chronic diffuse interstitial lung disease
Chronic diffuse (widespread) interstitial lung disease is relatively uncommon in people with SLE. Chronic interstitial lung disease scars the lung. This scarred tissue acts as a barrier to the oxygen that normally moves easily from the lung into the blood.
Besides lupus, there are other reasons for this condition. Correct identification of the cause is necessary in order to chose the proper treatment.
Symptoms of chronic diffuse interstitial lung disease
- gradual onset of a chronic, dry cough
- pleuritic-like chest pains
- difficulty breathing during physical activity.
Diagnosing chronic diffuse interstitial lung disease
To determine the cause, special procedures are required, such as:
- bronchoalveolar lavage
- lung biopsy.
Treating chronic diffuse interstitial lung disease
Chronic lupus interstitial lung disease is primarily treated with corticosteroids, with varying results. In general, the lung function can be stabilized with treatment.
The progression of chronic interstitial lung disease can be measured with several tests that assess disease activity and the person’s response to therapy. These include:
- the pulmonary function test to assess the ability of the lungs to receive, hold, and use air
- the oxygen saturation test to measure how readily oxygen moves through the lung and into the blood stream; oxygen saturation is usually reduced in chronic interstitial lung disease
- high-resolution CT scans to look at the lung and chest structures. Pulmonary hypertensionOccasionally, people with lupus develop pulmonary hypertension or high blood pressure in the blood vessels within the lung. If severe, this can be life-threatening, and there tends to be little chance for improvement.Treating pulmonary hypertension
There is no uniformly successful medical treatment for pulmonary hypertension. Heart-lung transplants may be an option for some people with pulmonary hypertension caused by SLE.
Pulmonary emboli are blood clots that block the pulmonary arteries.
Symptoms of pulmonary emboli
- At first, the clots cause pleuritic (lung) pain and shortness of breath.
- These clots can lead to abnormal oxygen exchange in the lung and even death.
Diagnosing pulmonary emboli
- ventilation-perfusion (breathing and blood flow) scans of the lung
- angiography (dye injected into an artery)
- an evaluation for thrombophlebitis (inflammation of a vein due to a blood clot)
Risk factors in lupus for pulmonary emboli
- antiphospholipid antibodies
- decreased blood levels of protein S
- possible vascular damage
- prolonged bed rest.
Pulmonary hemorrhage, or bleeding into the lung, is a rare but potentially fatal complication of SLE.
Symptoms of pulmonary hemorrhage
- shortness of breath
- a cough
- blood-tinged sputum.
Diagnosing pulmonary hemorrhage
These symptoms are usually seen in the setting of multi-organ system involvement from SLE and a rapidly falling red blood count.
Treating pulmonary hemorrhage
Treatment usually includes high-dose corticosteroids with immunosuppressive agents. Aggressive supportive care is also crucial to maximize chance for recovery.
The broad array of cardiopulmonary problems associated with SLE requires a close working relationship between patient and physician. Preventive measures to reduce the number of flares and rapid evaluation of new or changing symptoms is crucial to minimize long-term problems. Treatment is always individualized to the type of heart and/or lung involvement. Ongoing medical supervision is essential to optimize therapy and prevent long-term side effects.