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Left Atrial Appendage Occlusion

Tests before the procedure

You will need some tests before you can have an LAAO.

Transesophageal Echo

A transesophageal echo (TEE) is a type of ultrasound test that uses sound waves to look at the parts of the heart. TEE helps give clear images of the atrium that can’t be seen with regular ultrasound.

TEE is done by passing a tube (called an ultrasound probe) down your food pipe (esophagus). The procedure is done through the esophagus since it lies right behind the heart and makes it easier to see the left atrium.

You will have a TEE about 4 weeks before having an LAAO and again 6 weeks after.


An echocardiogram is another type of ultrasound that uses sound waves to look at the size of the heart and see how well the valves and the heart muscle are working. You will have an echocardiogram after the LAAO procedure, before you go home.

Source: Northside Heart Echocardiogram

Electrocardiogram (ECG)

An electrocardiogram is a test that checks for problems with the electrical activity of the heart.

Blood Tests

Blood tests check how well your kidneys are working and how many blood cells you have (called blood count).

Computerized Tomography (CT) Scan

A CT scan uses x-rays to take detailed images of the inside of the body. A CT scan helps to measure the size of the left atrial appendage. Sometimes a dye (called contrast) is injected into your body before the scan to look for a blood clot in your heart. A CT scan is done 3 to 4 weeks before LAAO.

Current as of: January 25, 2022

Author: Cardiovascular Health and Stroke SCN, Alberta Health Services