An echocardiogram uses sound waves to produce a video image of the heart. The ultrasound waves bounce off of your heart and produce moving images that can be viewed on a video screen as the heart is contracting and relaxing. Many times it is used just to confirm that there is no heart defect or abnormality. The echocardiogram study consists of several parts, which may include:
M-mode Echocardiogram: These are tracings that delineate the motion of the heart. Measurements of the heart walls and chambers can be obtained from these motion tracings.
Two-Dimensional Echocardiogram: Real-time images of the heart are recorded on a VCR tape or compact disc (CD). This records real-time images of the moving heart as it is contracting and relaxing. It is very helpful in determining if there is any heart enlargement. It also checks to see if the contractility of the heart is normal or decreased. In addition, it may detect structural abnormalities of the heart valves. The study may also demonstrate a hole in the upper or lower middle wall of the heart as well as any narrowing of the arteries or the blood vessels that connect to the heart. The recorded images may also help the cardiologist determine if there is transposition of the great arteries or complex heart defects. It also helps to check for mitral valve prolapse.
Doppler Echocardiogram: This is the part of the echocardiogram that makes a whooshing noise as the blood flows through the heart valves, arteries, and heart chambers. This part of the ultrasound test determines the velocity of blood flow as it travels through the different parts of the heart. This could be a very useful test to determine any acceleration of blood flow as may be seen with an obstructed valve or narrowing in one of the arteries. It may also give an estimation of the pressures in the lungs and heart chambers. The Doppler study is useful in calculating pressure gradients across an obstruction or a hole in the heart.
Color-Flow Echocardiogram: This is the part of the Doppler echocardiogram where we can determine the direction of blood flow according to the color on the screen. Blood going away from the transducer looks blue, while blood coming towards the echocardiogram transducer looks red. In addition, there may be a mosaic of colors if there is turbulent flow as may be seen across a narrow blood vessel or heart valve. This is also helpful in detecting a leaky valve or a hole in the heart. This is a very sensitive instrument that may pick up a very mild degree of leakage in normal heart valves. This is what we call physiologic regurgitation (leakage). Virtually all normal human beings have physiologic regurgitation in one or more heart valves. This common finding is benign and does not need follow up. It does not imply that any abnormality is present.