Standard electrocardiography; Holter monitoring and exercise stress test. The normal electrocardiogram and modifications in the different cardiovascular diseases. Supraventricular and ventricular cardiac arrhythmias: pathophysiology, electrocardiographic pattern and clinical importance. Sinus node dysfunction and disease of heart conduction system: electrocardiographic pattern and clinical importance. Cardiac pacing: device classifications and their function; device implantation procedures; indications to implant; paced electrocardiogram. Gender differences will be underlined when approaching different types of arrhythmias