How the Cardiovascular System Works (and Fails)
Medically reviewed by Jeffrey S. Lander, MDMedically reviewed by Jeffrey S. Lander, MDThe cardiovascular system, also known as the circulatory system, includes the heart and blood vessels. It plays an important role in transporting blood to organs and tissues throughout the body.
Illustration by Zoe Hansen for Verywell Health
Labeled Parts of the Cardiovascular SystemThe diagram is labeled with the main parts of the cardiovascular system: the heart, arteries, capillaries, and veins.Heart: A Muscular PumpThe heart is a fist-sized organ in the chest that is responsible for pumping blood. It has four chambers: two upper chambers (atria) and two lower chambers (ventricles). These chambers are separated by valves to keep blood flowing in the proper direction.The right atrium and right ventricle receive oxygen-deprived blood from the body and pump it to the lungs to get oxygen. This blood travels to the left heart, where it's then pumped to the rest of the body to deliver oxygen to tissues.Arteries: Tubes to Delivery Blood Away From the HeartArteries are blood vessels that act as tubes to carry blood away from the heart. There are two main types of arteries: systemic arteries and pulmonary arteries.Systemic arteries take oxygen-rich blood from the heart to the body. These include the aorta and it's branches.Pulmonary arteries take oxygen-deprived blood from the right heart to the lungs to get more oxygen.The major arteries branch into smaller arteries, called arterioles. These connect to capillaries, where the direct exchange of nutrients and oxygen to the tissues occurs.Arteries have three layers, including a muscular layer that allows them to change their diameter (constrict or dilate) to control the flow of blood.Capillaries: Small Blood Vessels for Nutrient and Gas ExchangeCapillaries are microscopic blood vessels that receive oxygen-rich blood from arterioles. Capillaries allow gas (oxygen and carbon dioxide) and nutrients to flow between the blood to the body's tissues. Capillaries connect to veins which bring blood back to the heart.Veins: Tubes to Deliver Blood Back to the HeartVeins are blood vessels that carry blood back to the heart. In the lungs, they carry newly oxygenated blood back to the heart so it can be pumped to the body. In the rest of the body, they take the now oxygen-depleted blood from capillaries back to the heart so it can be pumped to the lungs.Veins have thinner walls than arteries. They also have valves that prevent blood from flowing backward.How the Heart Moves Blood Through BodyThe heart is a muscular organ responsible for the flow of blood in the body. The heart has a right and a left side, each with an upper chamber (atrium) and lower chamber (ventricle). The right atrium receives oxygen-deprived blood from the body. The blood travels across the tricuspid valve into the right ventricle, which pumps the blood across the pulmonic valve to the pulmonary arteries. The pulmonary arteries carry the blood to the lungs, where it receives oxygen.The now oxygen-rich blood travels to the pulmonary veins to the left atrium. From the left atrium, blood travels across the mitral valve into the heart's main muscular chamber, the left ventricle. The left ventricle pumps blood across the aortic valve into the aorta, the body's main artery.The aorta branches into many arteries that carry blood all over the body. These arteries further branch into arterioles, which bring blood to capillaries. In the capillaries, gas exchange occurs. This means oxygen travels to the tissues and carbon dioxide waste travels to the blood. From here, the blood is carried by veins back to the right side of the heart.This process is continuously occurring. The heart pumps typically 60–100 times per minute at rest to keep the blood flowing.What Affects Cardiovascular System Function?There are many things that can go wrong with the cardiovascular system. Cardiovascular disease, which includes heart attack and stroke, is the number one cause of death worldwide.Associated Conditions and DysfunctionSeveral conditions affect the function of the cardiovascular system. These can be broken down into problems with the heart or the blood vessels. Some of these conditions, like high blood pressure (hypertension) and early atherosclerosis, may not have any symptoms at all.Blood vessel problems can occur in arteries or veins. In arteries, plaque buildup, blood clots, tears, or ruptures can occur. Problems with arteries include:Atherosclerosis is the buildup of fatty cholesterol plaques in the blood vessels.High blood pressure is elevated pressures exerted on blood vessel walls. This increases the risk of heart attack and strokeDissection is a tear in the lining of an artery. This can occur in various arteries in the body. Major complications can arise from dissection in the aorta (aortic dissection) or coronary arteries (coronary artery dissection).Thrombosis is the formation of a clot in a blood vessel. This blocks blood flow, leading to poor oxygen supply to organs. It can cause heart attack and stroke.Embolism is a blood clot that travels from elsewhere in the body and gets lodged in a blood vessel, blocking off blood flow. This leads to damage of organs that rely on that particular blood vessel. A pulmonary embolism is an example of an embolism that travels to the arteries in the lungs.Aneurysm is an enlargement or bulge in part of an artery. This can occur in various parts of the body, and can cause serious complications if it bursts or ruptures.Vasculitis is inflammation of blood vessels.Congenital malformations of blood vessels are defects in blood vessels present at birth that cause difficulties with blood flow.Problems with veins include:Venous insufficiency is a condition in which veins can't get blood back to the heart as well as they should.Blood clots are masses of blood, such as in deep vein thrombosis, that can travel to the lungs to become a pulmonary embolism.Phlebitis is inflammation of a superficial vein, which often leads to blood clot formation (thrombophlebitis).Heart problems can involve the heart muscle, valves, coronary arteries, or electrical system. Common heart problems include:Myocarditis, or inflammation of the heart muscleArrhythmias (abnormal heart rhythms), such as atrial fibrillation or heart blockCongenital heart problems, like malformations of heart walls detected at or before birthCoronary artery disease, a common cause of heart attackHeart failure (cardiomyopathy), when the heart can't pump sufficient blood and oxygen to support organsMyocarditis, or inflammation of the heart muscleValvular heart disease, such as narrowing (stenosis) or leakiness (regurgitation) of the heart's valves
Cardiovascular EmergenciesSome forms of cardiovascular disease are life-threatening emergencies that require immediate treatment, like a heart attack, aortic dissection, and stroke. If you develop symptoms of these conditions, it's important to call 911 to be transported to the nearest emergency facility for medical care. Symptoms of cardiovascular emergencies include:Chest pressure or discomfort that may radiate to the neck, jaw, upper arm or backShortness of breathTearing chest or back painWeakness on one side of the face or body, confusion difficulty speakingSudden collapse or loss of consciousness
How to Support Your Cardiovascular SystemThe cardiovascular system is essential to health, so it's important to take care of it. There are several ways to keep your heart and blood vessels healthy. These include:Eat a heart-healthy diet with lots of vegetables, fruit, and fiber. Choose whole grains. Avoid sugary drinks and ultra-processed foods that are high in salt and saturated fats.Get regular physical exercise. Aim for at least 150 minutes of moderate-intensity exercise (like a brisk walk) over the course of a week, or 75 minutes of more vigorous exercise per week.Quit smoking and avoid secondhand smoke.Get quality sleep, aiming for seven to nine hours per night.See your healthcare provider to check your blood pressure, cholesterol, weight, and blood sugar and discuss ways to keep those values within healthy ranges.SummaryThe cardiovascular system includes the heart, arteries, capillaries, and veins. It plays a vital role in supplying blood with oxygen and nutrients throughout the body. Problems with the cardiovascular system are common, but many are preventable. Lifestyle management can help keep your cardiovascular system in good shape. This includes a heart-healthy diet, regular physical exercise, avoiding smoking, getting good sleep, and controlling risk factors. Read the original article on Verywell Health.
Welcome to Billionaire Club Co LLC, your gateway to a brand-new social media experience! Sign up today and dive into over 10,000 fresh daily articles and videos curated just for your enjoyment. Enjoy the ad free experience, unlimited content interactions, and get that coveted blue check verification—all for just $1 a month!
Account Frozen
Your account is frozen. You can still view content but cannot interact with it.
Please go to your settings to update your account status.
Open Profile Settings