What kind of examination should be done on the chest

Everyone should have a physical examination at least once a year, so that we can detect diseases in our bodies, prevent them before they happen or treat them in time. A full body examination requires many types of examinations. Some examinations are unnecessary, while some are necessary. So how do we distinguish which ones should be done and which ones should not be done? Today, let’s take a look with the editor to see what examinations should be done on the chest.

You should make an appointment with the cardiothoracic surgery department, and the examinations you need to do include a chest X-ray and an electrocardiogram.

Electrocardiogram (ECG or EKG) is a technology that uses an electrocardiograph to record the changes in electrical activity produced by the heart during each cardiac cycle from the body surface.

Electrocardiogram is one of the most commonly used examinations in clinical practice and is widely used. Applications include:

1. Record the electrical activity of a normal human heart.

2. Help diagnose arrhythmias.

3. Help diagnose myocardial ischemia, myocardial infarction and location.

4. Diagnose cardiac enlargement and hypertrophy.

5. Determine the effects of medication or electrolyte status on the heart.

6. Determine the status of artificial heart pacing.

The principle of electrocardiogram generation

The myocardial cell membrane is a semipermeable membrane. In the resting state, a certain number of positively charged cations are arranged outside the membrane, and the same number of negatively charged anions are arranged inside the membrane. The potential outside the membrane is higher than that inside the membrane, which is called the polarized state.

In the resting state, since the myocardial cells in various parts of the heart are in a polarized state and there is no potential difference, the potential curve recorded by the current recorder is straight, which is the isopotential line of the surface electrocardiogram. When myocardial cells are stimulated to a certain intensity, the permeability of the cell membrane changes, and a large amount of cations rush into the membrane in a short period of time, causing the potential inside the membrane to change from negative to positive. This process is called depolarization.

For the whole heart, the potential changes of myocardial cells during the sequential depolarization from the endocardium to the epicardium are recorded by the current recorder as depolarization waves, that is, the P wave of the atrium and the QRS wave of the ventricle on the surface electrocardiogram. After the cell depolarization is completed, the cell membrane discharges a large number of cations, causing the membrane potential to change from positive to negative and return to its original polarization state. This process occurs from the epicardium to the endocardium and is called repolarization.

Similarly, the potential changes during the repolarization process of myocardial cells are recorded by an electric current recorder and are called repolarization waves. Because the repolarization process is relatively slow, the repolarization wave is lower than the depolarization wave. The atrial repolarization wave is low and buried in the ventricular depolarization wave, making it difficult to identify on the surface electrocardiogram. The ventricular repolarization wave appears as a T wave on the surface electrocardiogram. After all the myocardial cells are repolarized, they return to a polarized state again. There is no potential difference between the myocardial cells in different parts, and the surface electrocardiogram records the isoelectric lines.