Cardiac tamponade is when fluid collects around the heart muscle, for instance, due to trauma. It puts strain on the heart and stops it working effectively. Symptoms include a drop in blood pressure and distended blood vessels. It needs urgent treatment.

In people with cardiac tamponade, also known as pericardial tamponade, fluid or blood builds up between the heart and the sac that surrounds the heart. This sac is called the pericardium.

The pericardium consists of two thin layers of tissue. This area usually contains a small amount of fluid to prevent friction between the layers.

However, an abnormally high level of fluid puts pressure on the heart and affects its ability to pump blood around the body properly. If the level of fluid builds up quickly, the condition can be life threatening.

Doctors consider cardiac tamponade to be a medical emergency.

In this article, we discuss the causes and symptoms of cardiac tamponade. We also describe the treatment options and the outlook for people with this condition.