Heart’s anatomy and function

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The human heart is a sophisticated organ in our human body. In a single day, the heart pumps about 100,000 times, which can be around three billion times in one’s lifetime. This diligent muscular organ performs the vital role of blood circulation in our body.
Though the tasks of the heart are immense, the size of a human heart can be compared to a closed fist. The primary role of the heart is to gather de-oxygenated blood from the entire body, and then the blood gets oxygenated in the lungs. The oxygenated blood is subsequently transported to the rest of the body.


The heart is located between the right and left lungs and the middle of the chest, and this space is known as the mediastinum. 


These chambers are enclosed by pericardium. It is a double-layered tissue membrane or the double-walled sac that surrounds the heart and contains the roots of the major blood vessels that draw out from the heart.
The pericardium has two layers, namely the visceral layer (it covers the outside of the heart) and the parietal layer (It forms a sac over the external region of the heart which contains the fluid in the pericardial cavity), and they both include serous pericardium.

Heart Walls

The heart walls have three layers, they are:
The epicardium is the outlying layer of the heart, and it is formed by a thin layer membrane that protects the outer part of the heart.
The myocardium is the muscular median layer of the heart that contributes to the thickness and is responsible for pumping activity.
The endocardium is the inner layer of the heart that lines the chambers and valves.

Internal Structure of the Heart

Heart Chambers

The heart contains four chambers. Septa divides the heart into two, right and left. The upper cavity part on both sides is called the atrium, and the lower one is called the ventricle. The partition between the chambers prevents the mixing of oxygen-rich blood and carbon-dioxide-rich blood. 
Atria are thin and possess less muscular walls. They are smaller in size compared to ventricles. They receive blood from the circulatory system. 
Ventricles are thick-walled chambers responsible for pumping blood out into circulation.
The right ventricle and right atrium are relatively smaller than the left counterparts. The presence of myocardium decides the thickness of the heart chamber walls. The walls comprise fewer muscles than the left half, and the size variation is based on their functions. 

Heart Valves

Tricuspid Valve

It has three leaflets and separates the right atrium from the right ventricle. It allows blood flow from the right atrium to the right ventricle. The tricuspid valve stops the backflow of blood from the right ventricle to the right atrium.

Pulmonary Valve

It also has three leaflets, like a tricuspid valve, and divides the right ventricle from the pulmonary artery. The blood is facilitated in its transfer from the right ventricle to the lungs through the pulmonary artery, enabling the acquisition of oxygen. The function of the pulmonary valve is to impede the retrograde flow of blood from the pulmonary artery back into the right ventricle.

Mitral Valve

It has two leaflets and separates the left atrium from the bottom left ventricle. It allows blood flow from the left atrium to the left ventricle. The mitral valve stops the backward blood flow from the left ventricle to the left atrium.

Aortic Valve

It has three leaflets and separates the bottom left chamber (left ventricle) from the aorta. It allows blood to go to the heart from the left ventricle via the aorta. An aortic valve prevents the backward blood flow from the aorta to the left ventricle.

Blood Vessels

Blood vessels fetch blood to the lungs, where oxygen enters the bloodstream and the body.
Arteries transfer oxygen-rich blood from the heart to body tissues. Pulmonary arteries are an exemption because they have poor oxygen in the lungs.
Veins transfer oxygen-poor blood back to the heart. Capillaries are tiny blood vessels where the body interchanges oxygen-rich and oxygen-poor blood.

Coronary Artery

The heart manages its blood demand through its vascular system, known as coronary circulation. The leading blood supplier to the body is the aorta, which is divided into two coronary blood vessels. These coronary arteries can be further divided into smaller arteries, supplying oxygen-rich blood to the heart muscle. 
The right coronary artery gives blood mainly to the right side of the heart, namely the right atrium, right ventricle, bottom portion of the left ventricle and back of the septum. 
The right half of the heart is smaller than the left because it pumps blood only to the lungs. The left coronary artery bifurcates into the left anterior descending artery and the circumflex artery, resulting in oxygenated blood to the left ventricle of the heart.
The left anterior descending artery gives blood to the front of the septum and the front and bottom of the left ventricle. The left half of the heart is big and more muscular since it drives blood to all body parts.

Electrical conduction system

The heart’s pumping action is managed by an electrical conduction system that reconciles the contraction of the various chambers of the heart and controls the pace and rhythm of your heartbeat.
The Sinoatrial (SA) node oversees sending the signals that, in turn, make your heartbeat. The Atrioventricular (AV) node carries electrical signals from the heart’s upper chambers to its lower ones.

Heart Beats

A complete contraction and relaxation of the heart is called a heartbeat. Usually, the heartbeat beats around 70 to 72 times a minute while resting. 
A stethoscope is an instrument that measures our heartbeat. The heart beats faster during and after exercise because the body requires additional energy.

Heart Disease

Heart disease or cardiovascular disease includes many types of heart problems. Some are congenital, and others are acquired during a lifetime. The most common heart disease has:
Angina is chest pain resulting from a lack of blood flow. Heart attacks happen when part of the heart muscle dies from loss of blood flow.
Heart failure occurs when your heart can’t pump blood to meet the body’s needs. Arrhythmia is a problem with the heart rate or rhythm of the heartbeat.

The primary symptom of a heart attack in women is similar to that in men, typically manifesting as chest pain, pressure, or discomfort lasting more than a few minutes or occurring intermittently.

Normal Heart Rate for Women

The normal heart rate for women usually falls within the range of 60-100 beats per minute. Various factors such as age, level of physical activity, and overall health can influence the heart rate. It is also normal for a woman’s heart rate to rise during pregnancy.

How to reduce the chances of getting heart disease

Importance of cardiac health insurance

Considering the seriousness and prevalence of heart-related diseases, cardiac health insurance has become mandatory nowadays.

The Star Cardiac Care Insurance Policy is a comprehensive heart insurance plan that offers preventive care coverage such as cholesterol screenings, annual checkups, and blood pressure monitoring. It helps in the early detection of cardiac problems and the implementation of preventive measures.


The heart is the most complex working muscle in the entire body. A healthy heart is essential to live healthily and happily. It does the enormous task of supplying your body with the right amount of blood. 


1. What are the three main functions of the heart?

The three primary functions of the heart are pumping blood throughout your body, maintaining blood pressure and controlling your heart rate.

2. What is the structure of the heart?

Your heart is a four-chambered muscular organ shaped roughly like a man’s closed fist. 

3. What is a heart?

The heart is an important muscle that drives blood to the rest of the body. The blood pumped by the heart provides the body with the oxygen and nutrients it needs to function.


The Information including but not limited to text, graphics, images and other material contained on this blog are intended for education and awareness only. No material on this blog is intended to be a substitute for professional medical help including diagnosis or treatment. It is always advisable to consult medical professional before relying on the content. Neither the Author nor Star Health and Allied Insurance Co. Ltd accepts any responsibility for any potential risk to any visitor/reader.

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