Avoiding the left internal mammary artery during anterior pericardiocentesis.

In patients with pericardial effusions who require anterior pericardiocentesis, it is important to avoid trauma to the left internal mammary artery. Such trauma could result in severe bleeding or tamponade. This article describes how the left internal mammary artery may be identified by duplex ultrasound, and therefore avoided. It is also important to ensure that the needle stick is just lateral to the artery, to avoid hitting the left lung.