This is a non-invasive, painless and risk-free heart scan using high frequency ultrasound waves reflecting off various structures of the heart to obtain real-time images (in one and two dimensions) of your beating heart. When combined with the Doppler technique, which records changes in frequency of sound waves, echocardiography can be used to measure blood flow through various chambers of the heart and heart valves and calculate pressure difference across valves. Doppler signals can be colour-coded to enhance visualisation of blood flow (termed Doppler colour-flow mapping) and is the best way to determine the degree of narrowing, calcification or leakage of a valve. 2D Echo/Doppler study is one of the most important non-invasive investigations used in the diagnosis of heart disease today.
Your heart specialist can obtain very valuable information from this test which include :

Assessment of the pumping function of the heart
Assessment of wall motion of the heart muscles in various chambers
Measurement of the dimensions of the heart chambers and the heart muscle thickness
Assessment of the structure and function of the heart valves
Looking for congenital abnormalities of the heart (e.g. hole in the heart, abnormal malposition of vessels and chambers of the heart)
Other structural and functional problems (e.g. clots in the heart chambers, fluid collection around the heart, heart tumour, etc)