Conventional echocardiography has long been the standard noninvasive imaging to assess the function of the heart. However, with the advancements in medical science, many more advanced forms of echocardiography have emerged. Among these, strain and stress echocardiography stand out for their enhanced ability to detect heart conditions at an earlier stage.
Keep reading to know more about strain and stress echocardiography, how they work, their unique benefits, and when each is recommended, which helps to keep you informed!
Understanding Echocardiography
Echocardiography is a test that uses sound waves to take live images of the heart, called an echocardiogram. It helps to monitor the functioning of the heart and its valves.
An electrocardiogram helps to detect information about
- The size and shape of the heart
- Blood flow through the heart chambers and valves
- Pumping function (ejection fraction)
- Pressure within the heart
- Presence of fluid around the heart
- Blood clots in the heart
- Aortic abnormalities
It is also used to detect congenital heart defects, valve disease, pericardial conditions, and heart failure.
Understanding Strain Echocardiography
An echocardiography with strain, also known as myocardial deformation imaging, is a newer and advanced technique that allows the healthcare provider to diagnose heart conditions earlier and make a more accurate prognosis.
The term strain in echocardiography represents the degree of deformation of the heart muscle (myocardium) during contraction and relaxation.
By measuring how much the heart muscle shortens or stretches with each heartbeat, it may reveal subtle changes in cardiac function that may not be visible with conventional echocardiography.
How does it work?
Strain echocardiography uses the speckle tracking method for its measurement. The different steps include:
- Preparation: A cardiac sonographer will advise the patient to lie on an examination table in the left side-lying position and apply gel to the chest area.
- Image acquisition: A cardiac sonographer will place a handheld device called a transducer over the chest area and move it.
- Speckle tracking: The ultrasound machine will identify natural acoustic markers in the myocardium. As the heart moves, the software tracks how these speckles deform, stretch, and move over time. The software calculates Global Longitudinal Strain to assess overall heart muscle function.
Why Is It Performed?
A strain echocardiogram is particularly used to identify early myocardial damage before symptoms develop. It is performed to
- Monitoring cardiotoxicity in patients undergoing chemotherapy
- Assessing radiation-induced heart damage
- Evaluate and monitor the people who have early stages of cardiomyopathy, heart failure, or pericardial disease.
- Evaluate the diabetic or hypertensive heart disease before conventional changes are seen
- Evaluate pericardial disease and constrictive cardiomyopathy
When Is It Recommended?
Strain ECHO is recommended for
- Cancer patients receiving cardiotoxic medications
- Patients with normal EF but suspected cardiac dysfunction
- Individuals with chronic hypertension or diabetes
- Athletes or individuals with unexplained fatigue or exertional symptoms
- Routine follow-up for known or suspected cardiomyopathies
Benefits
The different benefits of a strain echocardiogram include
- Detects subclinical heart damage earlier than standard echocardiography
- Identifies subtle myocardial dysfunction
- Helpful in high-risk but asymptomatic patients
- Useful for long-term monitoring of heart muscle function
Understanding Stress Echocardiogram
A stress echocardiogram is used to evaluate the heart’s function and structure under physical stress. It combines traditional echocardiography with combined exercise, typically performed on a treadmill or stationary bike. It is conducted before and after physical activity to assess how the heart responds to exertion.
It may reveal problems, including reduced blood flow, blocked arteries, or hidden heart conditions that may not appear when the heart is at rest.
How does it work?
The test normally takes between 45 to 60 minutes and is performed by a cardiac sonographer under the supervision of a physician.
- Preparation: A technician attaches electrodes to the chest, which is connected to an electrocardiograph monitor that tracks your heart rate.
- Imaging at rest: The sonographer performs an initial echocardiogram. An ultrasound wand is held in different positions on the chest to collect images.
- Exercise phase: The patient will be asked to exercise on a treadmill or stationary bicycle, starting slowly and gradually increasing intensity. Continue exercising until the patient reaches the target heart rate, depending on age and fitness levels.
- Post-exercise imaging: The sonographer then performs the repeat echocardiogram to evaluate how the heart functions under stress.
Why Is It Performed?
Doctors use an exercise stress echocardiogram to
- Diagnose coronary artery disease. Abnormal test results indicate that the heart is not pumping blood effectively, as there is a blockage in the blood vessels.
- Evaluate exercise-induced arrhythmias
- Detect ischemia or silent myocardial dysfunction
- Assess heart valve disease under stress
- Determine the need for angioplasty or bypass surgery
- Evaluate fitness for major surgery
When is it recommended?
Stress ECHO is usually performed when you have symptoms of heart disease, including
- chest pain or pressure, or discomfort
- dizziness
- rapid or irregular heartbeat
- shortness of breath
It is also recommended for individuals who are athletes, are about to have surgery, and are exposed to different conditions, including driving or working at high altitudes.
Benefits
The different benefits of stress ECHO include
- Assesses cardiac performance under stress
- Identifies blockages or narrowed arteries
- Especially in healthy or mildly symptomatic individuals
- Helps in tracking the improvement of heart function in patients recovering from stress cardiomyopathy
Strain Echocardiography Vs Stress Echocardiography: Key Differences
| Strain echocardiography | Stress echocardiography | |
| Primary use | Detect subclinical myocardial dysfunction | Evaluate for coronary artery disease and how the heart responds to physical stress or exertion |
| Method | Performed at rest using advanced ultrasound software (speckle-tracking) | Involves exercise or medication to stress the heart |
| Suitability | Suitable for high-risk but asymptomatic patients | Symptomatic patients with chest pain, shortness of breath, or suspected heart disease |
| Uses | Early detection of cardiomyopathies, chemotherapy-related heart damage, and hypertensive heart disease | Diagnosis of coronary artery disease, exercise-induced symptoms, ischemia |
| Time required | 30-45 minutes | 45-60 minutes, as it includes exercise time |
Table: Comparison of Strain and Stress Echocardiography
Conclusion
Strain ECHO is ideal for early detection of subclinical heart muscle abnormalities, especially in high-risk patients with no clear symptoms. However, stress ECHO is best suited for evaluating how well the heart handles physical stress, helping diagnose heart conditions like coronary artery disease.
If you are showing symptoms of heart disease, consult our experienced cardiologists at SGVP Holistic Hospital for an accurate diagnosis and personalized care for your heart care.
FAQs
Stress or strain echocardiography is not a replacement for regular echocardiography. They are advanced tools that are used when more detailed or specific information is needed. Strain ECHO is used for detailed heart muscle analysis, while stress ECHO is used for functional testing under exertion.
Stress ECHO is generally safe. Some people may rarely experience dizziness, shortness of breath, or an abnormal heart rhythm during the test. It is always done under medical supervision to ensure safety.
No, strain echocardiography is non-invasive and painless. It uses advanced ultrasound techniques and does not involve any exercise or medication. It is safe for most individuals, including those who may not tolerate physical stress.
An echocardiogram is used to help diagnose and detect damage from a heart attack, heart failure, congenital heart disease, problems with the heart valves, cardiomyopathy, and endocarditis.
