This paper describes an application to the study and evaluation of ECG signals acquired during cardiac rehabilitation of the patients who have suffered a heart attack. During this process, the patient performs exercise sessions according to a protocol in order to improve his cardiovascular response after suffering a heart attack or other ischemic event. These exercises should be done under medical supervision and it has developed a wireless monitoring system called Movicorde that is able to acquire a channel electrocardiogram (ECG) using a portable equipment and transmit the ECG signals to a monitoring station. An application was developed to allow the evaluation of the effect of exercise protocol for each patient from the ECG recording, in order to prevent further complications or alter the cardiac rehabilitation protocol.