Abstract: An automatic cardiac compression system that is portable, simple to install on a patient and provides effective cardiac compression on a wide range of patient sizes. The inventive device includes a housing including a removable board with straps, an arcuate arm pivotally attached to the housing, a reciprocating transmission attached to the arcuate arm by an adjustable connector, a variable speed motor mechanically connected to the reciprocating transmission, and a battery electrically connected to the variable speed motor. The user positions the patient upon the removable board with the sternum positioned directly below the distal end of the arcuate arm. The user then manipulates a control switch which operates the variable speed motor. The motor manipulates the arcuate arm so that the arcuate arm repeatedly engages the patient's chest to provide cardiac compression.