Pericardial Effusion

Synonyms and related keywords:

pericardial effusion, pericardial sac, dropsy of pericardium, pericarditis, pericardial tamponade, pericardiocentesis, pericardioscopy, malignant pericardial effusion, leukemia, lymphoma, idiopathic effusions, Beck triad of pericardial tamponade, hypotension, muffled heart sounds, jugular venous distension, pulsus paradoxus, pericardial friction rub, hepatojugular reflux, Ewart sign, hepatosplenomegaly, cyanosis, hydropericardium, congestive heart failure, valvular disease, mediastinal lymphoma, Hodgkin disease, metastatic breast cancer, bacterial pericardial effusion, viral pericardial effusion, tuberculous pericardial effusion, parasitic pericardial effusion, HIV-related pericardial effusion, fungal pericardial effusion, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, vasculitides, uremia, postpericardiotomy syndrome, chylopericardium, myxedema, radiation-induced pericardial effusion

INTRODUCTION

Background: Pericardial effusion defines the presence of an abnormal amount and/or character of fluid in the pericardial space. It can be caused by a variety of local and systemic disorders, or it may be idiopathic. Pericardial effusions can be acute or chronic, and the time course of development has a great impact on the patient's symptoms. Treatment varies, and is directed at both removal of the pericardial fluid and alleviation of the underlying cause, which usually is determined by a combination of fluid analysis and correlation with comorbid illnesses.

Pathophysiology: The pericardial space normally contains 15-50 mL of fluid, which serves as lubrication for the visceral and parietal layers of the pericardium. This fluid is thought to originate from the visceral pericardium and is essentially an ultrafiltrate of plasma. Total protein levels are generally low; however, the concentration of albumin is increased in pericardial fluids owing to its low molecular weight.

The cause of abnormal fluid production depends on the underlying etiology, but usually it is secondary to injury or insult to the pericardium (ie, pericarditis). Transudative fluids result from obstruction of fluid drainage, which occurs through lymphatic channels. Exudative fluids occur secondary to inflammatory, infectious, malignant, or autoimmune processes within the pericardium.

Clinical manifestations of pericardial effusion are highly dependent upon the rate of accumulation of fluid in the pericardial sac. Rapid accumulation of pericardial fluid may cause elevated intrapericardial pressures with as little as 80 mL of fluid, while slowly progressing effusions can grow to 2 liters without symptoms.

Frequency:

• In the US: Few large studies have characterized the epidemiology of pericardial effusion. Pericardial effusion has been found in 3.4% of subjects in general autopsy studies. Small pericardial effusions often are asymptomatic.

  A higher incidence of pericardial effusion is associated with certain diseases. Twenty-one percent of cancer patients have metastases to the pericardium. The most common are lung (37% of malignant effusions), breast (22%), and leukemia/lymphoma (17%). Patients with HIV, with or without AIDS, are found to have increased prevalence, with 41-87% having asymptomatic effusion and 13% having moderate-to-severe effusion.

Mortality/Morbidity: Dependent upon etiology and comorbid conditions

• Idiopathic effusions are well tolerated in most patients. As many as 50% of patients with large, chronic effusions were asymptomatic during long-term follow-up.

• Pericardial effusion is the primary or contributory cause of death in 86% of cancer patients with symptomatic effusions.

• Survival rate for patients with HIV and symptomatic pericardial effusion is 36% at 6 months, 19% at 1 year.

Race:

• No consistent difference among races is reported in the literature.

• AIDS patients with pericardial effusion are more likely to be white.

Sex:

• No sexual predilection exists.

Age:

• Observed in all age groups

• Mean occurrence in fourth or fifth decades; earlier in patients with HIV