Heart Operation and Maintenance Manual

The heart is one of the most important organs in the human body. It is the driving force of the circulatory system. Its main function is to provide power for blood flow and "pump" blood to various parts of the body (Figure 1).

Figure 1 The heart “pumps blood” throughout the body

The embryo begins to form a primitive heart in the second week. The primitive heart tube is the prototype of the heart. By the eighth week of the embryo, the framework of the heart and blood vessels has been formed. The heart beats from the beginning of life and keeps working as life continues until the end of life. The end of a life is often expressed by "the heart stops beating". It can be seen how important the heart, a "part", is to the whole body, a "machine" (Figure 2)!

Figure 2 The human body is a “machine” that cannot do without the heart, an important “part”

The following is a brief introduction to the basic structure, function and maintenance methods of this important "part" of the heart.

1. Heart Floor Plan

The heart is a two-story building, a duplex villa (Figure 3). The one on the left is called the Left Heart, and the one on the right is called the Right Heart.

Figure 3 The heart (left) and its “floor plan” (right)

It has 4 rooms: the upstairs room is called "room", which is divided into the left atrium and right atrium; the downstairs room is called "chamber", which is divided into the left ventricle and right ventricle (Figure 4).

It has 4 valves: aortic valve, pulmonary valve, mitral valve, and tricuspid valve.

It has walls: the atrial walls and the ventricular walls, both of which are made of myocardium.

It has plumbing: the blood vessels of the heart.

It has circuits: the heart's electrical conduction system.

Figure 4: Diagram of the structure of the heart

2. The Door of the Heart

The technical term is valve. Some have two doors that open opposite each other, while others have three doors that open opposite each other (Figure 5). They can only move in one direction, that is, they act as one-way valves.

Figure 5 Heart valve

These doors are not ordinary. If the door is not opened wide, the space for entry and exit will become smaller, which is called "valvular stenosis" (Figure 6). At this time, the blood flow is blocked.

Figure 6 Valvular stenosis

It may be that the hinges between the door frame and the door are not flexible, and the door is stuck halfway open.

It may be that the two doors were hitting or blocking each other, so the space for the doors to open was smaller.

If the door is not closed tightly and leaks air, it is called incomplete closure (Figure 7). At this time, blood will flow back.

Figure 7 Valvular regurgitation

Maybe the door was too small when I bought it at the beginning, so the size doesn’t match.

Maybe the door is of poor quality and broke, so the one-way opening and closing door became a two-way opening and closing door.

Maybe the door has aged due to being used for a long time.

If this door falls, it is called valve prolapse. At this time, it will also cause valvular insufficiency and regurgitation (Figure 8).

Figure 8 Valvular prolapse

Maintenance instructions:

Heart valve disease can generally be examined through physical examination with a stethoscope, color Doppler echocardiography, chest X-ray, chest CT, cardiac interventional examination, electrocardiogram, etc.

Repair Instructions:

Method 1: For mild symptoms, drug treatment is suitable.

Method 2: Severe insufficiency, reflux or prolapse requires surgical operation, generally using molding and replacement, which is a major repair!

Method three: There are differences between domestic and imported valves, and between biological valves and mechanical valves. Please be sure to go to a regular 4S shop for maintenance!

3. The Walls of the Heart

The technical term is myocardium. If there is a hole in this wall - air or rain leaking - it is called atrial septal defect or ventricular septal defect (Figure 9).

Figure 9 Atrial septal and ventricular septal defects

If the walls are too thick, the room becomes smaller, and this is called hypertrophy (Figure 10).

Figure 10 Myocardial hypertrophy

It could be that the walls were thick when the house was built, which is natural, and this is called "hypertrophic cardiomyopathy." It could also be that it was "trained" by high blood pressure.

If the wall is evenly thick, the room will be small, the blood inside will be less, and the blood pumped out will not be enough. Or, if the wall is not thick enough, it will block the door! The blood cannot be pumped out! You will go black (black eyes), faint, or even die suddenly!

If the walls are too thin, the room may be larger, but it will be very fragile and have no strength to contract. This is called dilated cardiomyopathy (Figure 11).

Figure 11 Dilated cardiomyopathy

Maintenance instructions:

Echocardiography, chest x-ray, cardiac MRI, electrocardiography, cardiac catheterization, and endomyocardial biopsy.

Repair Instructions:

Method 1: Mild symptoms are generally treated with medication.

Method 2: Severe hypertrophy requires surgical operation to remove the hypertrophic part, which is a major repair!

Method 3: The heart is scrapped and a new one is transplanted.

4. Water pipes of the heart

The heart's water pipes, that is, the coronary arteries on the surface of the heart, are used to transport blood to the heart itself and nourish the myocardium (Figure 12).

Figure 12 Coronary arteries

Water pipes will inevitably age and lose their elasticity after being used for a long time, which is called arteriosclerosis. If you always pour "garbage" (such as low-density lipoprotein cholesterol, etc.) into them, it may cause the water pipes to narrow and become blocked, which is called atherosclerotic plaques. When the water pipes are narrow, the water flow is not smooth. When the water pipes are blocked, the water flow is directly cut off. Without the nutrition of blood, the myocardium will be ischemic or even necrotic (Figure 13).

Figure 13 Myocardial infarction

Maintenance instructions:

Electrocardiogram (including dynamic electrocardiogram), cardiac ultrasound, myocardial stress test, blood test, coronary CT angiography, coronary artery angiography, radionuclide myocardial perfusion imaging, etc.

Repair Instructions:

Method 1: Conservative and simple method, medication or thrombolytic therapy (Figure 14). Just like car maintenance, medication can adjust blood pressure, blood lipids, and blood sugar, giving the engine a chance to clean.

Method 2: Heart stent. Stents are placed to open the coronary arteries on the surface of the heart. Especially for acute myocardial infarction, rapid and effective stent implantation can effectively prolong the patient's life.

Method 3: Coronary artery bypass grafting. As the name suggests, vascular bypass grafting is to avoid the blocked area, take a blood vessel from other parts, cross the blocked blood vessel, and establish a new channel to ensure the normal flow of blood needed by the heart.

Figure 14 Coronary artery stenosis inspection method

This is a major repair, and it is recommended that you go to a large, regular 4S shop for the repair.

5. The circuitry of the heart

The professional term is the cardiac electrical conduction system. The sinoatrial node is the generator (also known as the body's own pacemaker). The electricity passes through the sinoatrial bundle to the "relay station" atrioventricular node (if the generator stops working, it can generate electricity temporarily), and then continues to pass through the His bundle to the left and right bundle branches (Figure 15).

Figure 15 Cardiac conduction system

Under the guidance of this circuit, the heart contracts and relaxes. If there is a problem with the circuit, the light may not light up, or it may flicker randomly.

If there is a problem with the pacing and conduction of the heart, abnormal heart rhythm, frequency or activation sequence may occur, and bradycardia, sinus arrest, tachycardia, arrhythmia, etc. may occur (Figure 16).

Figure 16 Irregular heartbeat

Maintenance instructions:

Static ECG, dynamic ECG, stress ECG, intraesophageal ECG, intracardiac ECG, wearable dynamic ECG monitoring, bedside ECG monitoring, etc.

Repair Instructions:

Method 1: Install a pacemaker (Figure 17). Pacemakers are divided into single-chamber, dual-chamber and triple-chamber.

Method 2: Radiofrequency ablation. Mainly applicable to arrhythmia diseases such as supraventricular tachycardia and ventricular tachycardia. Be sure to go to a large regular 4S store for maintenance.

Figure 17 Pacemaker

6. Heart contractility

The heart is like a pump that pumps blood throughout the body. The power of the pump is called contractility (Figure 18). If there is a problem with the pump, the contractility is too weak, and the blood pumped to the body will not be enough, which may cause diseases such as insufficient blood supply to various organs.

Figure 18 The heart beats vigorously

7. Postscript

The heart is a high-end suite, and the most important thing is the water pipe! If there is a problem with the water pipe, the wall will rot, the door will break, and the electricity will be messy! So pay attention to protecting the water pipe!

The heart is the most sophisticated instrument in the body. Daily maintenance is essential. Once it is out of repair, it will consume fuel for life; if it is not properly maintained, it will kill you! For example, myocardial damage caused by coronary heart disease cannot be regenerated. Once ischemia leads to necrosis, it can cause myocardial infarction at the mildest and heart rupture at the worst, leading to sudden death! Unfortunately, there are more and more patients with coronary heart disease now, which is directly related to "eating more and moving less"!

After reading this instruction manual on the use and maintenance of the heart, I hope that students will “take action instead of just thinking” and start being a “loving” person right away.

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