The Left Ventricle of the Heart
The left ventricle is one of the four hollow chambers of the heart. Being the largest chamber, it has an ovular shape and it occupies most of the left lateral and anterior planes of the heart. It also occupies most of the apex of the heart. The walls of the left ventricle are denser and stronger than that of the right ventricle. The thicker walls of the left ventricle support its tremendous workload of pumping blood at great pressure out of the heart.
As the left atrium contracts, the mitral valve opens, which releases stored oxygen rich blood into the left ventricle. The left ventricle fills with this blood then it contracts forcefully and the aortic valve opens. The left ventricle pushes the blood through the aortic valve to the aorta where it leaves the heart and is distributed throughout the body. For this reason the left ventricle is a major part of the systemic circulation process.
For the heart to perform properly, the functions of the left ventricle must also perform properly. It should relax quickly after each contraction so the oxygenated blood stored in the left atrium can fill it quickly. On the other hand, it should also contract quickly and with a lot of force to push this vital blood into the aorta. The force and pressure from the left ventricle has to be strong enough to overcome the aortic pressure so the blood will push forward. The pressure of the left ventricle also needs to be strong enough to stretch the aorta to accommodate sudden increases in blood volume. To maintain the needs of the body, the left ventricle needs to be able to quickly adapt its pumping capacity signaled by the nervous system. For example, the left ventricle should increase its pumping capacity signaled b...
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Works Cited
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4. Right Ventricular hypertrophy (RVH) – In a normal heart, the left ventricle has a rather thicker wall than the right due to the fact that it has to pump oxygenated blood to the body as opposed to the right ventricle which only needs to pump deoxygenated blood to the lungs. However, Tetralogy of Fallot causes an enlargement of the right ventricular muscle due to the pulmonary stenosis in the pulmonary
In this figure, SN = sinus node; AVN = AV node; RA = right atrium; LA
“Hypoplastic left heart syndrome accounts for 9% of all critically ill newborns with congenital cardiac disease, causing the largest number of cardiac deaths in the first year of life.(2) ” HLHS is a severe heart defect that is present at birth. HLHS combines different defects that result in an underdeveloped left side of the heart. This syndrome is one of the most challenging and difficult to manage of all of the congenital heart defects. Multiple portions on the left side of the heart are affected including the left ventricle, the mitral and aortic valve, and the ascending aorta. These structures are greatly reduced in size, or completely nonexistent causing the functionality of the left heart to be reduced, or non-functional all together.
The blood circulates through coronary arteries and then to smaller vessels into cardiac muscle (myocardium). The blood flow is influenced by aortic pressure, which increases in systole, and the pumping activity of the ventricles. When the ventricle contracts, in systole, the coronary vessels are compressed by the contracted myocardium and partly blocked by the open aortic valve therefore the blood flow through the myocardium stops.
of the heart: one chamber is on the top and one chamber is on the
The heart is an extraordinary structure that is the base of all human life. However, it similar to the uncomplicated functions of water pumps. As the heart beats, blood is distributed throughout the body using a network of blood vessels. The functions of the heart can be kept in regular and healthy conditions through exercise. Exercise has an effect on the blood that is circulating through the body. That circulating blood makes the heart desire more oxygen, causing the heart rate to increase rapidly to keep up with activity demand.
The cardiovascular system - The cardiovascular system is responsible for transporting nutrients and removing gaseous waste from the body. It consists of the heart, which powers the whole process, the veins, arteries, and capillaries, which deliver oxygen to tissue at the cellular level. The cardiovascular system carries blood that is low in oxygen away from the heart to the lungs via arteries, where oxygen levels are restored through the air once oxygenated, this blood is then carried throughout the body via arteries, keeping our organs and tissue alive. The cardiovascular system is the workhorse of the body, continuously moving to push blood to the cells. If this important system ceases its work, the body dies.
The ventricles send blood to the heart and are larger and stronger. Heart valves are another important aspect of the heart and body. We have atrioventricular and semilunar valves which help block regurgitation of blood. The heart has two states, it has a systole state where the heart is contracting to push blood out and diastole where the heart relaxes so the heart can fill back up with blood.
The Tell-Tale Heart: An Analysis In Edgar Allan Poe’s short-story, “The Tell-Tale Heart,” the storyteller tries to convince the reader that he is not mad. At the very beginning of the story, he asks, "...why will you say I am mad? " When the storyteller tells his story, it's obvious why. He attempts to tell his story in a calm manner, but occasionally jumps into a frenzied rant.
Elaborate: The cardiac cycle of the heart is divided into diastole and systole stages. Diastole refers to the period of relaxation experienced by the atria and ventricles. Systole is the contraction of the atria and ventricles. The pattern of blood flow starts in the left atrium to right atrium then into the left ventricle and right ventricle. During its course, blood flows through the mitral and tricuspid valves. Simultaneously, the right atrium is granted blood from the veins through the superior and inferior vena cava. The job of the superior vena cava is to transport de-oxygenated blood to
The heart serves as a powerful function in the human body through two main jobs. It pumps oxygen-rich blood throughout the body and “blood vessels called coronary arteries that carry oxygenated blood straight into the heart muscle” (Katzenstein and Pinã, 2). There are four chambers and valves inside the heart that “help regulate the flow of blood as it travels through the heart’s chambers and out to the lungs and body” (Katzenstein Pinã, 2). Within the heart there is the upper chamber known as the atrium (atria) and the lower chamber known as the ventricles. “The atrium receive blood from the lu...
Just as breast cancer is killing our African American women, heart disease is also one of the major diseases killing our women. Heart disease is one of the nation’s leading causes of death in both woman and men. About 600,000 people die of heart disease in the United States (Americas heart disease burden, 2013). Some facts about heart disease are every year about 935,000 Americans have a heart attack. Of these, 610,000 are a first heart attack victim. 325,000 happen in people who have already had a heart attack. Also coronary heart disease alone costs the United States $108.9 billion each year. This total includes the cost of health care services, medications, and loss of productivity. Deaths of heart disease in the United States back in 2008 killed about 24.5% of African Americans.
The heart is two sided and has four chambers and is mostly made up of muscle. The heart’s muscles are different from other muscles in the body because the heart’s muscles cannot become tired, so the muscle is always expanding and contacting. The heart usually beats between 60 and 100 beats per minute. In the right side of the heart, there is low pressure and its job is to send red blood cells. Blood enters the right heart through a chamber which is called right atrium. The right atrium is another word for entry room. Since the atrium is located above the right ventricle, a mixture of gravity and a squeeze pushes tricuspid valve into the right ventricle. The tricuspid is made up of three things that allow blood to travel from top to bottom in the heart but closes to prevent the blood from backing up in the right atrium.
the aortic valve, between the left ventricle and the aorta. heart_chambers.jpg Each valve has a set of "flaps" (also called leaflets or cusps). The mitral valve normally has two flaps; the others have three flaps. Dark bluish blood, low in oxygen, flows back to the heart after circulating through the body. It returns to the heart through veins and enters the right atrium.
The heart is a pump with four chambers made of their own special muscle called cardiac muscle. Its interwoven muscle fibers enable the heart to contract or squeeze together automatically (Colombo 7). It’s about the same size of a fist and weighs some where around two hundred fifty to three hundred fifty grams (Marieb 432). The size of the heart depends on a person’s height and size. The heart wall is enclosed in three layers: superficial epicardium, middle epicardium, and deep epicardium. It is then enclosed in a double-walled sac called the Pericardium. The terms Systole and Diastole refer respectively and literally to the contraction and relaxation periods of heart activity (Marieb 432). While the doctor is taking a patient’s blood pressure, he listens for the contractions and relaxations of the heart. He also listens for them to make sure that they are going in a single rhythm, to make sure that there are no arrhythmias or complications. The heart muscle does not depend on the nervous system. If the nervous s...