GUSTOIMAGES / SCIENCE PHOTO LIBRARY GUSTOIMAGES / SCIENCE PHOTO LIBRARY
Heart pacemaker. Coloured frontal X-ray of the chest of a male patient with a heart pacemaker (upper right). The heart is the red mass at centre right, in between the lungs (white). The pacemaker is a device that has leads (blue and red) to supply regular electrical impulses to the heart, so that it beats normally. Pacemakers are surgically fitted in patients with a malfunctioning sinoatrial node, the part of the heart that initiates the heartbeat, or in patients with a heart block, which impairs the nerve impulses generated by the node. Pacemakers can either provide a regular impulse or discharge only when a heartbeat is missed.
Model release not required. Property release not required.