The difference between electrocardiogram, cardiac color Doppler ultrasound and coronary angiography

Time : 2023-05-30

A few days ago, a user in the heart health exchange group complained: "I felt uncomfortable before. I went to the hospital for an examination. After an electrocardiogram, the doctor said that I needed to have a cardiac color Doppler ultrasound, and then asked me to do a coronary angiography. Why? To do so much? What is the difference between the three?"


Have you also encountered the same problem?

Electrocardiogram,  cardiac color Doppler ultrasound, and coronary angiography are three common detection methods in clinical practice. What is the difference between them?

1. Electrocardiogram


There are three main types of ECG: conventional ECG, Holter ECG, and treadmill exercise ECG.

Among them, the routine electrocardiogram is the one that we will basically come into contact with in our daily physical examination, and it is the one we are most familiar with.

a. Routine electrocardiogram

Routine electrocardiogram examination is the simplest, most economical and safest non-invasive method for clinical diagnosis of cardiovascular system diseases.

Routine electrocardiogram examination is of decisive significance to common various arrhythmias, myocardial ischemia, including abnormal origin of excitation and various conduction disorders.

b. Dynamic electrocardiogram

General ambulatory electrocardiogram is an effective supplement as routine electrocardiogram.

Dynamic electrocardiogram plays an important role in the qualitative and quantitative diagnosis of arrhythmia and myocardial ischemia, the determination of the cause and nature of paroxysmal syncope, vertigo and palpitations, the evaluation of drug efficacy and the function evaluation of pacemaker.

The 24-hour ambulatory electrocardiogram can record all abnormal electric waves, detect various arrhythmias and myocardial ischemia with or without symptoms in various states within 24 hours, and provide accurate and reliable basis for the diagnosis of various heart diseases .

c. Tablet exercise electrocardiogram


Exercise treadmill electrocardiogram, also known as electrocardiogram stress test, is currently the most commonly used auxiliary method for diagnosing coronary heart disease. It is mainly used to consider patients with coronary heart disease, but the electrocardiogram does not have myocardial ischemia.

It is an examination method to determine whether there is coronary heart disease by inducing myocardial ischemia by increasing the heart load through exercise.

Treadmill exercise test is of great significance to the diagnosis of coronary heart disease, judgment of lesion degree and prognosis.

2. Cardiac ultrasound

Some heart diseases cause changes in the heart's electrical activity, but other heart diseases do not affect the heart's electrical activity, but only the structure of the heart itself.

In this case, the patient's disease condition cannot be accurately known through the electrocardiogram alone, and further examination is required in combination with color Doppler echocardiography.

Cardiac color Doppler ultrasound reflects changes in the structure of the heart. It can reflect whether the walls of the atrium and ventricle are defective or thickened, whether the atrium and ventricle are enlarged, and whether the valves of the heart are narrowed or incompetent. It can reflect whether the systolic and diastolic functions of the heart are normal, and whether the ejection fraction is normal.

For example, the heart is enlarged, the heart contraction is weak, and the valve of the heart is not closed tightly. The diagnosis and discovery of these diseases all rely more on echocardiography.

Cardiac color Doppler ultrasound is mainly used for the diagnosis of various congenital heart diseases, heart valve diseases, cardiomyopathy, pericardial diseases and the evaluation of heart function.

3. Coronary angiography

Coronary angiography is the use of a catheter along the artificial entrance of the radial artery (at the wrist) or the femoral artery (at the thigh) to the opening of the coronary arteries in the heart, and a contrast agent (visible on X-rays) is injected into the coronary arteries , so that the internal shape of the coronary artery and the blood flow velocity in the coronary artery can be displayed, so that it can be clearly seen whether the coronary artery has stenosis, plaque, stenosis location, degree, range, etc.

Coronary angiography is a commonly used and effective method for diagnosing coronary heart disease, and is considered the "gold standard" for diagnosing coronary heart disease.

However, because coronary angiography is an invasive examination, it will cause certain harm to the patient's body. At the same time, the fee for coronary angiography is relatively high.

Therefore, it is generally used for re-diagnosis and treatment after the first few inspections are completed and it is basically judged to be coronary heart disease.

At the same time, it is also used for review after stent surgery.

In summary, the three of them have different uses, and in some diseases, they can form an effective complementarity, irreplaceable, and can better determine the disease.