An echocardiogram is a basic diagnostic method used in cardiology to observe the heart in motion (beating) in real time. The Doppler and colour Doppler ultrasound methods are applied to these images to analyse the blood flow through the heart. This study provides information on the structures of the heart and the way they work. It can determine the size (diameter, areas and volumes) and calculate weight in grams as well as the force of contraction and the volume each heartbeat pumps. Finally it measures the speed and the pressure of blood flowing through each of the valves.