A new method for classifying cardiac abnormalities is here proposed based on the electrocardiogram (ECG). The ECG may manifest abnormal heart patterns, which are generally known as arrhythmias. MIT-BIH arrhythmia database and AAMI standards are used for machine learning purposes considering the patient-oriented scheme. Heartbeat time intervals and morphological features processed by a 2-D time-frequency wavelet transform of ECG signals are combined into an image, which carries relevant information from each heartbeat. These dataset images are used as input to train and evaluate the classifier, which is essentially a 6 layers convolutional neural network (CNN), resulting in powerful artifact discrimination. The training set is artificially augmented to reduce the imbalance of the five heartbeat classes, achieving better results. A significant achieved overall accuracy of 95.3% of the proposed method, compared to some of the most relevant published methods, permits to expect effective results when applied to real patients Ver menos