Chronic pericarditis: causes, symptoms, treatment, prognosis

What is chronic pericarditis?

Chronic pericarditis Is an inflammation of the pericardium (the elastic, two-layered membrane that covers the heart) that begins gradually, it exists for a long time and leads to the accumulation of fluid in the pericardial cavity or thickening pericardium. Symptoms may include shortness of breath, coughing, and fatigue. Echocardiography and sometimes other tests are used to make a diagnosis. If the cause of pericarditis is known, treatment is prescribed, and salt restriction and diuretics are recommended to relieve symptoms. Sometimes surgery is required to remove the pericardium.

Pericarditis is considered chronic if it lasts more than 6 months. There are two main types of chronic pericarditis.

• chronic exudative pericarditis;
• chronic constrictive pericarditis.

At chronic exudative pericarditis fluid slowly accumulates in the pericardial space between the two layers of the pericardium.

Chronic constrictive pericarditis, which is extremely rare, as a rule, develops as a result of the formation of scar (fibrous) tissue throughout the pericardium. Fibrous tissue tends to harden and shrink over time, resulting in compression (compression) of the heart. Such compression prevents the normal filling of the heart with blood and leads to the development of heart failure. However, due to compression, the heart does not increase in size, as it does in most types of heart failure. Since blood pressure is now required to fill the compressed, fibrous pericardium of the heart with blood, the pressure in the veins that return blood to the heart increases. As a result of the increased venous pressure, fluid seeps through the walls of blood vessels and collects in other areas of the body, for example, under the skin. Sometimes constrictive pericarditis develops more rapidly (eg, within a few weeks after cardiac surgery) and is considered subacute.

Causes

As a rule, the cause of chronic exudative pericarditis remains unknown. However, it can be caused by cancer, tuberculosis or insufficient thyroid function (hypothyroidism), and in some cases it occurs in persons with chronic kidney disease.

As a rule, the cause of chronic constrictive pericarditis also remains unknown. The most common known causes are viral infections, radiation therapy breast cancer or lymphomas localized in the chest, as well as cardiac surgery. Chronic constrictive pericarditis can occur due to the same disorders that lead to the development of acute pericarditis, for example, rheumatoid arthritis, systemic lupus erythematosusprevious trauma or bacterial infection.

While TB was previously the most common cause of chronic pericarditis in the United States, TB currently accounts for only 2% of all cases. In Africa and India, tuberculosis continues to be the most common cause of all forms of pericarditis.

Signs and symptoms

These symptoms include:

• dyspnea;
• cough;
• fatigue.

Dyspnea and coughing is due to increased pressure in the veins of the lungs, resulting in fluid seeping into the pulmonary alveoli.

Fatigue develops due to the fact that the affected pericardium interferes with the normal functioning of the heart, so the heart loses its ability to pump enough blood to meet needs organism.

Other common symptoms include fluid accumulation in the abdomen (ascites) and legs (edema). Sometimes fluid builds up in the space between two sheets of the pleura, the membrane that covers the lungs (called pleural effusion). However, chronic pericarditis usually does not cause pain.

Sometimes the inflammation is asymptomatic.

Chronic pericardial effusion may cause little or no symptoms with gradual, slow accumulation of fluid. If fluid builds up slowly, the pericardium may expand gradually so that symptoms caused by strong pressure on the heart (cardiac tamponade) may be absent. However, with rapid fluid accumulation or the inability of the pericardium to stretch sufficiently, compression and cardiac tamponade can occur.

Diagnostics

Diagnostics include:

• echocardiography;
• catheterization or imaging studies of the heart using MRI or CT.

Symptoms are important clues in the diagnosis of chronic pericarditis, especially in the absence of other causes for decreased cardiac function, such as increased arterial pressure, coronary heart disease, cardiomyopathy or heart valve disease.

Echocardiography is often done to confirm the diagnosis. It can detect fluid in the pericardial cavity and the formation of fibrous tissue around the heart. She can also confirm the presence of cardiac tamponade.

In the course of X-ray examination, calcium deposits in the pericardium can be detected. These deposits develop in almost half of patients with chronic constrictive pericarditis.

The diagnosis can be confirmed in one of two ways.

• cardiac catheterization;
• diagnostic imaging.

Cardiac catheterization can be used to measure blood pressure in the chambers of the heart and large blood vessels. These measurements help doctors distinguish pericarditis from similar conditions.

Magnetic resonance imaging (MRI) or computed tomography (CT) can be used to determine the thickness of the pericardium. Normally, the thickness of the pericardium is less than 3 mm, but with chronic constrictive pericarditis, it usually increases to about 5 mm or more.

A biopsy may be done to determine the cause of chronic pericarditis, such as confirmation of a tuberculous lesion. A small sample of the pericardium is removed during a diagnostic surgical procedure and examined under a microscope. Alternatively, a sample can be taken using a pericardioscope (fiber optic tube, used to examine the pericardium and obtain tissue samples), which is inserted through an incision in the chest cage.

Laboratory tests of blood and pericardial fluid samples may be required to determine the cause of pericarditis.

Treatment

Therapy may include:

• treatment of the underlying disease;
• sometimes removal of pericardial fluid or pericardium;
• for chronic constrictive pericarditis, restricting salt and diuretics to relieve symptoms.

Treat known causes of chronic exudative pericarditis if possible. If heart function is not impaired, doctors use a wait and see approach.

If the disease is accompanied by symptoms, or if there is a suspicion of infection, perform balloon pericardiotomy, drainage with a needle (pericardial puncture) or surgical drainage.

- Chronic constrictive pericarditis.

For patients with chronic constrictive pericarditis, salt restriction in the diet and diuretics (drugs that stimulate the elimination of fluid) are recommended to relieve symptoms.

However, the only cure for chronic constrictive pericarditis is surgical removal of the pericardium. Surgical treatment helps about 85% of patients. However, since the risk of death after surgery is 5 to 15% (and higher in those with severe cardiac failure), most patients do not undergo surgery unless the disease significantly interferes with daily activities.

Doctors usually wait until symptoms become severe (but not so severe that the patient is at rest) before performing surgery. By limiting dietary salt and taking diuretics, the disease can be controlled for months or even years, and this may be the only treatment needed if constrictive pericarditis is subacute (for example, after surgery for heart).

Forecast

Long-term survival after pericardiectomy for constrictive pericarditis depends on the underlying etiology and overall clinical condition of the patient. Patients with idiopathic constrictive pericarditis survive relatively well.

The prognosis is closely related to the underlying cause, but long-term survival is more likely with surgery, and the best results are obtained if surgery is offered early.