ECG, Echo, or TMT?

When you visit a cardiologist with symptoms such as chest discomfort, breathlessness, palpitations, dizziness, or unexplained fatigue, you may be advised to undergo one or more heart tests. Among the most commonly used cardiac investigations are ECG, Echo, and TMT.

Although these tests are often discussed together, each one provides different information about the heart. An ECG records the heart's electrical activity, an Echo uses ultrasound to examine the heart's structure and function, and a TMT evaluates how the heart responds to physical exercise.

Understanding the difference between ECG, Echo, or TMT can help you understand why your doctor recommends a particular test. However, the right test depends on your symptoms, medical history, risk factors, and clinical examination.

What Is an ECG?

An electrocardiogram, commonly called an ECG or EKG, is a quick and painless test that records the electrical activity of the heart. Small electrodes are placed on the chest and sometimes the arms and legs to capture the heart's electrical signals.

An ECG can provide information about:

• Heart rate
• Heart rhythm
• Electrical conduction
• Certain abnormal heart rhythms
• Changes that may suggest a heart attack
• Some signs of heart muscle abnormalities

Because an ECG is quick and non-invasive, it is frequently used as an initial cardiac investigation.

When Is an ECG Recommended?

A doctor may recommend an ECG when you have:

• Chest pain or discomfort
• Palpitations
• Dizziness
• Fainting
• Shortness of breath
• Unexplained fatigue
• Suspected arrhythmia
• Possible heart attack
• Certain cardiovascular risk factors

An ECG may also be included as part of a health screening or pre-operative evaluation when clinically appropriate.

What Is an Echo?

An echocardiogram, commonly called an Echo, is an ultrasound examination of the heart. It uses sound waves to create images that help doctors assess the heart's structure and function.

Unlike an ECG, which primarily evaluates electrical activity, an Echo allows the doctor to examine how the heart looks and moves.

An Echo can assess:

• Heart chambers
• Heart muscle movement
• Pumping function
• Heart valves
• Blood flow
• Thickness of heart walls
• Certain structural abnormalities

It can be particularly useful when a doctor suspects heart failure, valve disease, structural heart problems, or other conditions affecting how the heart functions.

When Is an Echo Recommended?

Your doctor may recommend an Echo if you have:

• Shortness of breath
• A heart murmur
• Suspected valve disease
• Heart failure symptoms
• Abnormal ECG findings
• Swelling of the legs
• Known heart disease
• Certain congenital heart conditions

The exact type of echocardiogram depends on the clinical question. A standard transthoracic Echo is performed externally through the chest and is commonly used to evaluate heart structure and function.

What Is a TMT?

A TMT, or Treadmill Test, is an exercise stress test used to evaluate how the heart responds when the body is physically active.