The pericardium is a thin membrane-shaped sac that surrounds the heart and separates it from the other anatomical structures around them. Acute pericarditis is the name given to the inflammation of the pericardium, which may be caused by several situations, including drugs, trauma, stroke, cancer, kidney failure and infections, especially viral origin.
The most common symptom of acute pericarditis is a severe chest pain, which often worsen during deep inspiration. Because it is an inflammation of the heart, the pain of pericarditis can be easily confused with the pain of a heart attack, especially if it is affecting a patient at high cardiovascular risk.
In this article we explain what is acute pericarditis, which are the causes, symptoms, complications and how is the treatment.
Various organs of our body are covered with thin membranes, being "bagged" and isolated from adjacent organs. For example, the brain is covered by meninges, lungs, pleura, and the intra-abdominal organs by the peritoneum. The heart, in turn, is "bagged" within the pericardium a fibrosserosa membrane, which serves to isolate the heart and reduce friction with the bodies around it.
The pericardium is composed of two thin layers, which are practically stuck to each other, separated by only a minimal amount of liquid, about 20 ml, which acts as a kind of lubricant.
During the frame pericarditis, inflammation can cause the volume of the pericardial fluid increases. Up to 90 to 120 ml of additional fluid can accumulate in the pericardium without causing significant problems to the heart of previously healthy individuals. However, the accumulation of larger volumes can compress the heart, which reduces its blood pumping capacity and causes a medical emergency call cardiac tamponade.
Viral infection is the most common cause of acute pericarditis, accounting for up to 10% of cases. This form of pericarditis is usually self-limited, with 1-3 weeks and usually arise in times viral epidemics, especially those caused by the flu (influenza virus), cold or by coxsackie virus.
In these cases, pericarditis is preceded by a respiratory virus frame or viral gastroenteritis. The patient improved viral infection, but days later begins to complain of severe chest pain.
The viral pericarditis can occur in children, adolescents, adults or elderly. Men are more affected than women.
In addition to viruses, other possible causes of pericarditis are:
Unknown cause (called idiopathic pericarditis) - In many cases, the cause of pericarditis arises for no apparent reason, and its cause ends up not being clarified, this is not a problem since many of these patients improved only with common anti-inflammatory drugs. It is believed that many of these are idiopathic pericarditis, in fact, the viral pericarditis identified.
Bacterial infection - usually comes after cases of pulmonary infection or infectious endocarditis. Tuberculosis is another possible cause. A bacterial infection of the pericardium may also occur as a complication of cardiac surgery. In addition to bacteria, fungi can also be the cause.
Radiation - Most of these cases are complications by the use of radiation to treat cancers in the chest, especially breast cancer, lung cancer or lymphoma.
Trauma - The trauma chest, whether by a car crash or a piercing injury, type knife or firearm projectile, can cause trauma to the heart that induce the occurrence of a pericarditis.
Myocardial infarction - a myocardial infarction (heart attack) causes injury to the heart muscle and in some cases, can cause pericarditis.
Drugs and toxins - It's unusual, but eventually some drugs can cause pericarditis, including: hydralazine, isoniazid, procainamide, phenytoin, phenylbutazone, thrombolytics, and other anticoagulants.
Renal failure - Chronic renal failure in advanced stages can cause the accumulation of toxins in the body, causing irritation of the pericardium.
Cancer - pericarditis can occur when a malignant tumor causes metastases to the heart. The most common cases occurring in breast cancer, lung or Hodgkin's lymphoma.
Autoimmune diseases - Several immunological diseases can cause pericarditis. Ente them, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, mixed connective tissue disease and vasculitis.
Inflammatory bowel disease - pericarditis can occur in patients with ulcerative colitis or Crohn's disease.
The main symptom of acute pericarditis is an intense chest pain that arises suddenly, affects the entire central region of the chest, worsens during deep inspiration, coughing or at bedtime, but presents some relief when the patient sits and bends the trunk forward. The pain is often described as a stab in the chest; some say they feel as if they had been stabbed in the heart.
In many patients, however, the pain of pericarditis can not be so typical and easy distinction. In some cases, the pain is not as acute, and complains of pressure or weight patient chest radiating to the shoulders, neck or back. In these situations, it may be difficult to distinguish between pericarditis and other causes of chest pain, such as myocardial infarction, pulmonary embolism or aortic aneurysms.
In children, pericarditis may present as abdominal pain instead of chest pain.
Low-grade fever, palpitations, fatigue, malaise and cough are common symptoms, but usually stay in the background given the intensity of chest pain.
Pericarditis in tuberculous in origin, the picture is not so acute, and the patient usually has fever, night sweats and weight loss.
In most cases, particularly those of viral origin, pericarditis is a self-limiting event that responds well to the administration of anti-inflammatory and healing up after 1 to 3 weeks. However, pericarditis can develop life-threatening complications.
The two main complications of pericarditis include: cardiac tamponade and constrictive pericarditis.
a) Cardiac tamponade
In some cases of pericarditis can be accumulation of fluid between the pericardium blades. In about 5% of cases, this accumulation is so great that excess fluid compresses the heart chambers, preventing the heart to fill and pump blood properly. Cardiac tamponade is a medical emergency, as the patient may go into shock by circulatory failure of the heart pump.
b) constrictive pericarditis
Although uncommon, pericarditis some people, particularly those with long inflammation and with frequent recurrences may develop a permanent scarring and thickening of the pericardium. In these patients, the pericardium loses its elasticity, it becomes hard and begins to compress the heart, hindering proper blood pumping. The constrictive pericarditis usually cause fatigue, shortness of breath and swelling in the legs and abdomen.
The diagnosis of pericarditis can be made clinically by clinical history and physical examination. Listen to the heart with a stethoscope, the doctor may notice that there is a sound of friction during the heartbeat, called pericardial friction. This signal occurs by friction between the two inflamed layers of the pericardium.
It is hard to think of pericarditis when a young patient without risk factors for cardiovascular disease reaches the emergency department with chest pain typical of pericarditis and pericardial friction presents the cardiac auscultation. But even in theoretically easy cases like the one above, we need to carry out further tests to confirm the diagnosis.
In general, the patient ends up being investigated for the leading causes of chest pain, which includes performing blood tests, chest X-ray, electrocardiogram and echocardiogram. From the results of these tests, most cases of pericarditis can be clarified.
Most patients with acute pericarditis caused by viruses or unknown cause, treatment can be done with rest and aspirin or some common anti-inflammatory. If the pain does not improve within a week, the framework needs to be reassessed.
Another drug that can be used are the colchicine, which, besides improving the symptoms of acute pericarditis, also reduces the risk of recurrence.
In patients who can or can not tolerate the use of drugs described above, the option is corticosteroids.
When the cause is identified pericarditis, as in the cases of tuberculosis or infection by bacteria, also part of treatment using antibiotics directed to such infections. If the patient has lupus or rheumatoid arthritis, the doctor needs to better control these diseases to achieve treat pericarditis.
