What is an electrocardiogram (ECG)?
An electrocardiogram is a noninvasive test that measures the electrical activity of the heart. An ECG takes approximately five minutes and is painless. Many other heart conditions can be diagnosed with an ECG, for example
- abnormal heart rhythms,
- evidence of prior heart attack,
- evidence of an evolving heart attack,
- unstable angina,
- congenital heart abnormalities,
- evidence of abnormal blood electrolytes,
- evidence of inflammation of the heart (myocarditis, pericarditis).
What is a treadmill test (TMT)?
Symptoms of heart disease tend to show up when the person is exercising because that’s when the heart needs a higher level of oxygen delivery. However, for a person with heart disease, the coronary arteries can’t deliver the amount of oxygenated blood needed because of the coronary artery blockage. That’s why stress tests require the patient to perform a strenuous activity under a doctor’s supervision, such as walking or running on a treadmill. An ECG is taken of the person before, during, and after the stress tests. TMT have a 60%-70% accuracy rate for detecting blockages in the coronary arteries. If a patient is unable to walk on a treadmill, a stress test can be used with medication that mimics the physiology of exercise without the patient needing to walk, and the heart can be imaged with nuclear techniques, also called a myocardial perfusion scan or stress thallium test.
What is echocardiography?
Your doctor may want to use echocardiography to detect heart disease. Echocardiography uses sound waves to generate images of the heart. The test serves as a tool to see how well the heart muscle is functioning. A normal heart pushes at least 50%-60% of the blood in the ventricle out to the body when it beats. Echocardiography can show if the heart muscle is weaker than this, which could indicate heart disease. Echocardiography is also useful in detecting various structural abnormalities in the heart.
Why use computerised tomography ( Cardiac CT)?
Computerized tomography tests, also known as CT scans, take detailed images of blood vessels to show whether they have narrowed. In general, this test is used to exclude any blockages in your heart arteries and also to show that heart disease is not present, but still coronary angiography is the gold standard in detecting blockages in coronary arteries.
What is coronary angiography?
During coronary angiography, doctors guide a catheter into the coronary arteries. Next, a small amount of radiographic contrast (a solution containing iodine, which is easily visualized with X-ray images) is injected into each coronary artery. X-ray images are then taken, which are called the angiogram. Angiographic images accurately reveal the extent and severity of all coronary arterial blockages.