Miniature external cardiac pacemaker pulse generator Type EV4542, by Devices Ltd., England, 1979

Developed in the 1960s, cardiac pacemakers give out regulated electrical impulses. These stimulate the contraction of the heart muscles to provide sufficient rate of heartbeat. This miniature external cardiac pacemaker created this electronic impulse within the heart. It is attached to a catheter. The catheter is inserted into the arm vein and led into the heart. The generator can be strapped to the patient’s wrist. It was adjustable for sensitivity and output. This type EV4542 pacemaker generator was made by Devices Limited in England. Pacemakers are now often implanted into the chests of patients rather than carried externally.