ANATOMY OF THE
CIRCULATORY SYSTEM The human heart is truly the ultimate pump. Its 4 chambers feed the entire circulatory system and the lungs. It beats 60-100 times a minute, 24/7/365. It is by far the hardest working muscle in your body. The heart is slightly larger than your fist and is located under the sternum in the center of the chest. In the average lifetime it will beat over 3 BILLION times!
Because it is the hardest working part of the circulatory system, the heart needs its own supply of blood. It accomplishes this with the coronary arteries. These supply lines of the heart encircle the entire muscle providing oxygen and blood to all 4 of its chambers. Along with the heart, the circulatory system includes: the arteries and arterioles, which take oxygenated blood away from the heart; the veins and venioles, which return deoxygenated blood to the heart; and the capillaries and capillary beds, which perform the actual oxygen exchange. The pulmonary arteries and veins transport blood from the heart to the lungs and back.
The job of the circulatory system is to deliver blood, which contains oxygen and nutrients, and to remove waste products from all parts of the body. The circulatory system has a built-in regulator, which varies its performance based on your body’s needs. It will provide more oxygenated blood during times of increased need by speeding up the heart and dilating blood vessels to allow more blood flow. It will slow down your heart rate during times of rest. All of this is under the control of the central nervous system in the brain.
CARDIOVASCULAR
DISEASE Cardiovascular disease is a broad and all- encompassing term. Despite what the name may suggest, it’s not just a particular condition, but rather a collection of diseases and conditions. Everything from heart attacks to varicose veins represent this type of disease. Technically, it can refer to any disorder in any of the various parts of your cardiovascular system.
Cardiovascular Disease (CVD) includes all conditions of the heart as well as the arteries and veins that supply oxygen to vital life-sustaining areas of the body.
These include the brain, the heart itself, and other vital organs. Without oxygen, the tissue or organ will die.
Heart disease and stroke are the most common cardiovascular diseases. They are the 1st and 3rd leading causes of death for men and women in the U.S. This adds up to almost 40% of all deaths. More than 610,000 Americans die of cardiovascular disease each year, equalling 1 in every 4 deaths! Cardiovascular diseases are the world’s largest killers, claiming 17.1 million lives each year.
These conditions are more common among people aged 65 and older; however, the deaths from heart disease among people aged 15–34 have increased. Of the nearly 1 million annual deaths in the United States, 160,000 are ages 35 to 64. Over 80% of deaths from cardiovascular disease globally take place in low and middle-income countries and occur almost equally in men and women.
Cardiovascular disease has two main components: • Diseases of the heart (cardio) • Diseases of the blood vessels (vascular)
Coronary artery disease is one of the most common forms of heart disease and the leading cause of heart attacks. In this condition, the arteries of the heart have become narrowed and obstructed, thereby restricting blood flow. This is a largely preventable type of vascular disease. Coronary artery disease can lead to other heart problems, such as chest pain (angina) and heart attack (myocardial infarction).
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