Transesophageal echo (TEE) is used when your doctor needs a more detailed view of your heart. For example, TEE may be used to look for blood clots in your heart. A doctor, not a sonographer, performs this type of echo.

The test uses the same technology as transthoracic echo, but the transducer is attached to the end of a flexible tube. The tube will be guided down your throat and into your esophagus (the passage leading from your mouth to your stomach). From this angle, your doctor can get a more detailed image of the heart and major blood vessels leading to and from the heart.

For TEE, you'll likely be given medicine to help you relax during the test. The medicine will be injected into one of your veins. Your blood pressure, the oxygen content of your blood, and other vital signs will be checked during the test. You'll be given oxygen through a tube in your nose. If you wear dentures or partials, you'll have to remove them.

The back of your mouth will be numbed with a gel or a spray so that you don't gag when the transducer is put down your throat. The tube with the transducer on the end will be gently placed in your throat and guided down until it's in place behind the heart.

The pictures of your heart are then recorded as your doctor moves the transducer around in your esophagus and stomach. You shouldn't feel any discomfort as this happens.

Although the imaging usually takes less than an hour, you may be watched for a few hours at the doctor's office or hospital after the test.