The electrocardiogram is the most frequently used test method when heart disease is suspected. Since it is inexpensive and has no physical burden, it has been widely used as a test for heart disease since ancient times. Specifically, it records the state of electrical activity of the heart in the form of a graph, which is useful for the diagnosis and treatment of heart disease. In various heart diseases, subtle changes in electricity occur in the heart. It is possible to capture the electrical changes before the onset of symptoms.
A typical electrocardiogram is a 12-lead electrocardiogram with 4 limb leads and 6 chest leads attached to the chest. Electrocardiography is roughly divided into 1) resting electrocardiogram, 2) 24-hour Holter electrocardiogram, and 3) exercise stress electrocardiogram.
CVIC Oimachi and CVIC Iidabashi can perform 1) resting electrocardiogram and 2) 24-hour Holter electrocardiogram.
1. Resting electrocardiogram
It is used for general examinations such as health examinations. It is possible to detect diseases such as arrhythmia and myocardial infarction. This is a very important test, but it should be noted that there are limits to the diseases that can be detected by a resting electrocardiogram. For example, an arrhythmia can only be detected when it is present. The resting electrocardiogram usually records only a few seconds, so it cannot be detected unless there is an arrhythmia in that short time. The same is true for angina, which cannot be detected without testing when there are symptoms.
Myocardial infarction is a disease that is one step ahead of angina and is often possible with a resting electrocardiogram. Sudden onset acute myocardial infarction and unstable angina, which is a severe angina that may lead to myocardial infarction, can often be diagnosed by resting electrocardiogram. Cardiac hypertrophy, especially left ventricular hypertrophy, can also be diagnosed with an electrocardiogram.
In other words, if there is an abnormality in the resting electrocardiogram, further examination is required, but just because there is no abnormality does not mean that there is no illness.
2. Holter ECG (24-hour ECG)
In order to investigate arrhythmia and chest pain in detail, I carry a small electrocardiograph called Holter ECG for 24 hours and use it to record the electrocardiogram. With advances in equipment, it is now as small as a credit card.
The number of heartbeats (heartbeat) is said to be about 100,000 times a day for the average adult. The Holter ECG records all 100,000 heartbeats and is used to consider the following:
1. Number of arrhythmias
You can know what percentage of the total. Although it depends on the type and symptoms of arrhythmia described later, it is generally considered to be acceptable if it is 10% or less.
2. Types of arrhythmia
It is possible to distinguish between supraventricular arrhythmias from the atrium, which is the upper room of the heart, and ventricular arrhythmias, which are from the ventricle, which is the lower room. In addition, it is possible to distinguish between tachyarrhythmia in which the pulse becomes faster and bradyarrhythmia in which the pulse becomes slower. Since the treatment policy differs depending on the type of arrhythmia, it is important to examine what kind of arrhythmia it is.
3. Risk of arrhythmia
It is possible to infer whether the arrhythmia is a life-threatening severe arrhythmia. Dangerous arrhythmias can lead to sudden cardiac death and require immediate treatment.
4. Matching arrhythmia and symptoms
Holter electrocardiography is often set to press a button when symptoms occur. By examining the electrocardiogram near the button press (symptoms) in detail, it is possible to examine what kind of arrhythmia is actually related to the symptoms.
5. Presence or absence of myocardial ischemia
It is possible to determine if myocardial ischemia is occurring during Holter ECG. Angina cannot be diagnosed accurately without an electrocardiogram when chest pain is present. In that respect, the Holter ECG is a useful test for detecting angina. In particular, it is very useful for diagnosing coronary spasm angina caused by coronary artery spasm (spasm), which is a typical example of resting angina.
In addition, asymptomatic myocardial ischemia (asymptomatic angina) may occur, especially in diabetes. Even in that case, 24-hour monitoring with Holter ECG can detect the condition of myocardial ischemia.