This is another interesting 3D printing story from the Cardiac field:
http://3dprint.com/1300/3d-printed-e...art-disorders/

Doctors have been able to 3D print a membrane which is embedded with sensors and can go around a human heart. It can than measure key data points of a heart, even telling when someone may be having a heart attack. The other great feature about this device is it's ability to send electrical shocks to the heart to help treat certain serious conditions.