Fall 2010 - What Is an Echocardiogram?
Hello! Hello! Hello! Do you hear the echo? In the case of an echocardiogram, it’s different from your voice bouncing off the walls of the Grand Canyon, but sound waves do play an important role in this technology.
An echocardiogram or echo is a sonogram of the heart. Sound waves actually create a video image of the heart so we can see how well it is beating and if any abnormalities in the different structures of the heart are present.
Echocardiograms provide us with a host of information about a patient’s heart and vessels. Cardiologists use echocardiograms to diagnose, evaluate and monitor many conditions.
Some of these include:
- Heart damage related to heart attack
- Heart failure
- Valve disease/infection
- Transient ischemic attack
- Aortic stenosis
- Heart murmurs
- Atrial fibrillation
- Septal defect
How an Echo Works
A transthoracic echo is an easy, painless test that requires no fasting or other pre-testing preparation. In addition, the ultrasound does not involve radiation exposure. It is the same technology used in obstetrical practices and is very safe.
A sonographer specially trained in performing echocardiograms administers the test. While lying on your back, the sonographer will place electrodes on your chest. These provide specific information about the timing of different heart events, such as the filling and emptying of your heart’s chambers.
The sonographer will then spread a special gel on your chest. The transducer, a hand-held wand that sends and receives signals, is next. The transducer sends sound waves through the chest to the heart. The sound waves bounce (echo) off the heart. The transducer then picks up the echoing sound waves, sends them to a computer and creates images of your heart as it beats. The sonographer moves the transducer around your chest to capture different sides and structures of your heart. The images are then recorded for the cardiologist to view and interpret. All in all, the test takes about 45 minutes.
The transthoracic echo is the most common echo administered. Below are additional types of echocardiograms to help cardiologists diagnose, evaluate and treat other heart and vascular conditions.
Stress Echo — This echo helps the cardiologist evaluate your blood flow to the heart both at rest and under stress (i.e., during exercise). The sonographer will perform two sonograms — one while you are lying on the table at rest and one immediately after you exercise to view blood flow when the heart is beating faster and harder. If you cannot exercise, the sonographer can inject a medication called dobutamine, which makes the heart beat the same way it does during exercise.
Transesophageal Echo — Sometimes the lungs or ribs get in the way and the sonographer cannot get good images of the heart with a transthoracic echo. In this case, a cardiologist will often order a transesophageal echo (TEE). This test requires you to refrain from eating or drinking anything for six hours before it is performed. It is important that you tell the sonographer about any previous esophageal dilations or problems you have had with your esophagus, such as strictures, GERD, etc. You will also be given a sedative, so you will need a ride home after the test. During a TEE, the sonographer feeds a very thin tube with a transducer at its tip down your throat and esophagus to the area where the heart is located. Your throat will be numbed to keep you comfortable. Once there, ultrasound images can be taken. TEEs are often used to help the physician look for blood clots in a person who has atrial fibrillation and heart valve infections. It is also an important aid before and during a surgical heart valve repair procedure.
Doppler Echo — This test is often performed in conjunction with a transthoracic echo or a TEE to measure blood flow speed and pressure. The addition of Doppler technology does not require you to prepare any differently than you would for a TEE or a transthoracic echo.