The development of devices to monitor the electrical activity of the heart while the patient is carrying out their daily activities is a growing need worldwide. Reported in this paper is what has been done in the development of the hardware component within the project WHAM (Wireless Heart Arrhythmia Monitoring), led by the Group of Cardiovascular Dynamics of the Bolivarian Pontifical University. As a result of this work was a first working prototype with the ability to store cardiac events in a flash type SD and transmit them wirelessly to a server monitoring via a modem GSM-GPRS.