1) Cardiograph 2) Ekg 3) Tickertape 
instrument for recording unusual electrical fluctuations of the heart
device to record an electrocardiogram
An electrocardiograph, ECG, is a record of the electrical activity of the heart, obtained from electrodes connected to the chest. The tiny voltage at each electrode is amplified and connected to a pen producing a wavy line on continuously moving paper, or a similar line on a screen. Thus it shows as graphs the patterns produced at each heartbeat.
<apparatus> An instrument for recording the potential of the electrical currents that traverse the heart and initiate its contraction. ... (05 Mar 2000) ... 
(e-lek″tro-kahr´de-o-graf″) the apparatus used in electrocardiography.
Type: Term Pronunciation: ē-lek′trō-kar′dē-ō-graf Definitions: 1. An instrument for recording the potential of the electrical currents that traverse the heart.
electrocardiograph An instrument for recording the potential of the electrical currents that traverse the heart and initiate its contraction.
a galvanometric device that detects and records the minute differences in electric potential caused by heart action and occurring between different parts of the body: used in the diagnosis of heart disease. Also called
(EKG) An instrument that records the activity of the heart.