Heart Health

Heart 101: How Does Your Heart Work?

Heart is a vital organ of a human body. It is a hollow, cone-shaped muscle located between the lungs and behind the breastbone. Two-thirds of the heart is located to the left of the mid-line of the body and 1/3 is to the right. It continuously pumps oxygen and nutrient-rich blood throughout human body to sustain life. This fist-sized powerhouse beats (expands and contracts) 100,000 times per day, pumping five or six quarts of blood each minute, or about 2,000 gallons per day. The average weight of a human female heart is 9 ounces and a male heart is 10.5 ounces. The heart comprises less than 0.5 percent of the total body weight.

Blood is essential for the heart to perform its functions. The circulatory system of heart is responsible to pump blood through a system of blood vessels. The vessels are elastic, muscular tubes that carry blood to every part of the body.

The heart has three layers. The smooth, inside lining of the heart is called the endocardium. The middle layer of heart muscle is called the myocardium. It is surrounded by a fluid filled sac call the pericardium.  The right and left sides of the heart work together. The pattern described below is repeated over and over, causing blood to flow continuously to the heart, lungs, and body.

Right Side of the Heart:

Blood enters the heart through two large veins, emptying oxygen-poor blood from the body into the right atrium of the heart. As the atrium contracts, blood flows from human’s right atrium into right ventricle through the open tricuspid valve. When the ventricle is full, the tricuspid valve shuts. This prevents blood from flowing backward into the atria while the ventricle contracts. As the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.

Left Side of the Heart:

The pulmonary vein empties oxygen-rich blood from the lungs into the left atrium of the heart. As the atrium contracts, blood flows from your left atrium into your left ventricle through the open mitral valve. When the ventricle is full, the mitral valve shuts. This prevents blood from flowing backward into the atrium while the ventricle contracts. As the ventricle contracts, blood leaves the heart through the aortic valve, into the aorta and to the body.

You can read more about your heart at oladoc.com. You can also book an appointment with a top Cardiologist in Multan, Karachi and Islamabad through oladoc.com. Or call our helpline at 042-3890-0939 for assistance to find the RIGHT Doctor for your heart needs.

Disclaimer: The contents of this article are intended to raise awareness about common health issues and should not be viewed as sound medical advice for your specific condition. You should always consult with a licensed medical practitioner prior to following any suggestions outlined in this article or adopting any treatment protocol based on the contents of this article.

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