An electrocardiogram and echocardiogram (echo) are both noninvasive imaging tests that look at the functioning of your heart and can help identify heart disease.

An electrocardiogram (EKG or ECG) and echocardiogram serve different purposes.

An EKG captures the electrical activity of your heart using electrodes that are placed around your chest. It detects the heart rate and rhythm of your heart, but can also detect heart attacks

An echo is a type of ultrasound that uses sound waves to visualize your heart and chest cavity, allowing doctors to see how blood flows through the heart chambers and how effectively it is pumping.

A medical professional might order one or both types of tests for you depending on your symptoms.

Electrocardiogram purpose

An EKG is usually the first screening test for heart issues. Also known as a heart tracing, it provides data on your heart rhythm and your heart rate, which may indicate conditions like:

The data it provides can also give medical professionals clues about the potential causes of enlarged heart chambers and other abnormalities.

If a doctor suspects you may have had a heart attack, or if you experience chest pain, this may be your first test for the doctor to make a diagnosis

Echocardiogram purpose

An echo provides a moving picture of your heart and how it’s functioning. It can help doctors find and diagnose blood clots, heart valve disease, and other conditions. The medical professional can see and measure, in real time:

  • the size and thickness of your heart’s chambers
  • whether the valves are working properly
  • the flow of blood into, out of, and through your heart
  • the tissues that make up the sac around your heart, called the pericardium

An echo is commonly used to check recovery following a cardiac episode like a heart attack. Additionally, a doctor may order this test for you if you exhibit symptoms like shortness of breath, atypical blood pressure, irregular heartbeat, or heart murmurs.

Both an EKG and echo are considered noninvasive tests that take less than an hour.

Electrocardiogram procedure

  1. A technician or other medical professional will have you remove your clothes from the waist up and lie on a table.
  2. They will place sticky electrodes on your chest, and maybe your arms and legs.
  3. The electrodes record electrical activity and send the data to a computer that converts it to a graph for a heart specialist to interpret.
  4. Your technician will remove the electrodes.

You will be able to return to your daily activities immediately after.

Echocardiogram procedure

There are multiple types of echocardiogram, but the most common is a transthoracic echocardiogram, which is performed outside your body.

  1. A medical professional called a sonographer will have you remove your clothes from the waist up and lie on your back or on your left side. You can wear a hospital gown if you would like.
  2. In some cases, they may inject a saline solution or dye via your veins to make the heart look more pronounced.
  3. The sonographer will apply a gel to your chest.
  4. They will then move a small device called a transducer around the chest to get different images of your heart.
  5. They may ask you to change positions or take or hold a deep breath.
  6. After the test, they will wipe off the remnants of the gel.

You will be able to return to your everyday schedule immediately after.

EKG results can alert your medical professional to the presence of:

  • heart palpitations
  • arrhythmias (irregular heartbeat)
  • blocked or narrowed arteries

Following an echocardiogram, the sonographer will send the images with measurements to your doctor, who will review them and look for visual signs of any potential issues. These include:

  • the presence of masses like blood clots or tumors
  • cardiomyopathy, or damaged heart muscle tissue
  • pumping function of the heart
  • infective endocarditis, an infection in your heart’s chambers or valves
  • thick or thin ventricle walls
  • abnormal chamber size
  • poorly functioning valves
  • fluid around the heart

An EKG and an echo are complementary tests and what they reveal can help doctors make an accurate diagnosis. An echo is better for looking at structural problems with your heart and the way blood flows through it. An EKG is better for monitoring your heart’s electrical impulses.

An echocardiogram cannot directly show blockages in arteries. However, narrowing and clogged arteries can affect the heart’s pumping ability and wall motion, which may be noticeable to a medical professional.

An EKG can provide your doctor a partial answer to questions or concerns they may have. If it does not fully answer those questions, they may order an echocardiogram to provide more information.

An echocardiogram and electrocardiogram are two types of tests available to detect issues with your heart, alongside an MRI, CT scan and others. The data and information they provide medical professionals is different, and the two often complement each other. An EKG is less comprehensive than an echo, but it can still provide important information for follow-up.