The pericardium or pericardial sac is a double-layered membrane surrounding the heart. It is filled with a small amount of fluid, which allows the smooth pumping of the heart and decreases friction between the pericardial layers. Excessive build-up of fluid in the pericardial sac compresses and prevents the normal beating of the heart. It is therefore essential to remove the excess fluid from the pericardial sac.

Pericardiocentesis or pericardial tap is a procedure performed to remove the excess fluid from the pericardial sac with a needle and catheter (thin plastic tube).


Pericardiocentesis is indicated to relieve pressure in cardiac tamponade, a life-threatening condition in which the heart’s pumping ability weakens due to excessive fluid build-up. Other indications of pericardiocentesis include:

  • To test the cause of fluid build-up such as inflammation, infection, cancer or presence of blood
  • To relieve symptoms caused by fluid build-up such as shortness of breath


During the procedure, you will lie on an examination table. You will be under the effect of a mild sedative to help you relax and a local anaesthetic to numb the area around the chest. You will have an intravenous line in your arm to introduce fluids and medication. Your doctor inserts a needle and threads a catheter into the pericardial sac under the guidance of X-ray or echocardiography (use of sound waves to create images of the internal organs) to help position the catheter. The excess fluid is then drained. The catheter is either removed or retained for more drainage. A sample of the fluid is sent to the laboratory for examination.

Post-procedural Care

After the procedure, your blood pressure and pulse are monitored. The site of catheter insertion is examined for signs of infection. You should arrange for someone to drive you home after you are discharged.

Risks and Complications

Pericardiocentesis is generally a safe procedure, but as with any procedure, it involves certain risks and complications. These may include:

  • Collapsed lung
  • Heart attack
  • Irregular heart rhythm
  • Bleeding and infection
  • Punctured liver, stomach, lung or heart