Cardiac tamponade is an uncommon condition characterized by the accumulation of fluid in the pericardium (the sac surrounding the heart). This fluid can put so much pressure on the heart that it is unable to pump enough blood to meet the body’s demands. Fluid accumulation in the pericardial sac is known as pericardial effusion. Cardiac tamponade results when fluid collects rapidly or in large amounts, which interferes with the heart's ability to pump and fill with blood. 

Cardiac tamponade can be caused by trauma (such as a car accident), a coronary event (such as a heart attack) or cancer. Among the most common causes of tamponade are inflammation of the pericardium (pericarditis) and toxic accumulation in the blood, which is usually a result of kidney disease. However, other conditions may cause it as well.

Treatment for cardiac tamponade involves removing the fluid from the pericardium, which may be done with a needle and catheter combination (pericardiocentesis), balloon-tipped catheter or surgery. People at high risk for developing cardiac tamponade are urged to take anti-inflammatory medications and to learn the symptoms of cardiac tamponade in order to get immediate medical treatment at the first sign of danger.