First of all, there is a double-walled sac in which your heart is enclosed. This sac is called pericardium whereas the superficial part of it, which fits loose, is the fibrous pericardium. This part of your heart is extremely important for the well-being of this organ.
The fibrous pericardium anchors the heart to the structures which are surrounding the organ. It generally supports and protects the heart and helps to maintain an ideal level of the blood in this organ. In other words, the fibrous pericardium helps to avoid the condition in which the heart is overfilled with blood.
What else is located in your heart? There is the serous pericardium which is situated deep to the fibrous pericardium. It is a membrane in the form of a closed sac. The membrane is thin despite the fact that there are two layers of tissues one of which is called visceral and the other one is called parietal. The sac is placed around the heart.
One of the functions of the serous pericardium is the lubrication of the heart which creates an environment free of friction.
Another important part of the heart is its wall which consists of the three major layers. They are endocardium, myocardium and epicardium.
In fact, epicardium creates the layer of the serous pericardium which has been described above. Myocardium forms the bulk of the heart. The tissues which compose this layer of your heart are mainly cardiac muscles.
It is important to emphasise that the heart has special connective fibres which create the fibrous cardiac skeleton. This is an essential network of tissues which helps to maintain the form of the heart and prevent the valves from excessive stretching. The fibrous cardiac skeleton is not electrically excitable which means that it can limit the process of spreading of the electron potentials as well.
Endocardium is the third layer of the heart. This layer is composed of squamous epithelium which is a layer of endothelium. This layer is placed on the connective tissue layer.
The Vessels and Heart Chambers
You have already learnt about the division of the heart into two atria and two ventricles. It is important to emphasise that the heart is divided longitudinally by the interatrial septum and interventricular septum.
The atria of the heart are receiving chambers whereas the ventricles are the discharging chambers.
Speaking about the major veins which are connected with the heart, it is important to mention the superior vena cava, the inferior vena cava and the coronary sinus.
The superior vena cava is responsible for returning the blood which comes from the regions of the body situated superior to the diaphragm. The function of the inferior vena cava is returning the blood which has been received from the regions of the body located below the diaphragm. Additionally, the collection of the blood which is draining from the myocardium is the function of the coronary sinus.
There are also four pulmonary veins which are entering the left atrium. The function of these veins is the transport of the blood which comes from the lungs back to the heart.
The majority of the space in your heart is occupied by the ventricles. The main tissues which compose this part of your heart are muscles. It will be important to admit that the actual pumps of the heart are the ventricles.
You should know that the blood flows in your body in one direction. It starts to flow from the atria and goes to the ventricles. The one-way traffic is enforced with the help of valves which normally close and open according to the particular differences in the blood pressure.
Your body has atrioventricular, aortic and pulmonary valves.
Unfortunately, the complicity of such an organ as your heart means that various imbalances and disorders may take place there. It is extremely important to know what conditions can develop in the heart.
Coronary artery disease
It is common knowledge that a person should maintain an appropriate level of cholesterol in one’s blood. Coronary artery disease is just an example of a problem which can occur under the condition of not taking care of your blood vessels.
The arteries can become narrowed by the development of cholesterol plaques which will make it difficult for the blood to get into the heart. As a result, one can experience complete blockage of the heart or a heart attack which is actually a blood clot.
There are two major forms of angina such as stable angina pectoris and unstable angina pectoris. These two conditions are also usually caused by cholesterol.
Stable angina pectoris is the situation in which a person feels chest pain as well as discomfort because of the narrowed coronary arteries as the blockages make it impossible for the heart to get a sufficient amount of oxygen for the activity of the body. As the condition is stable, it means that a person do not experience any worsening of the symptoms and has a chance of getting better after having a rest.