Sample 1: Heart and Lung Diagram - Accessible Image Sample Book
A thorough understanding of the interaction between the heart and lungs . PVR is hyperbolic in relation to lung volume, with the nadir near the. Keeping your heart fit and strong can slow down the ageing of your brain,” to clarify the association between cardiac index and brain volume is required. by the US National Heart Lung Blood Institute as part of the larger. This image of the heart and lungs is taken from a middle school health textbook. or diagrams where the physical relationships between elements of the image.
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The Circulatory System
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The content needs to be extracted from the image and included in the description. The mitral valve separates the left atrium from the left ventricle. Two valves also separate the ventricles from the large blood vessels that carry blood leaving the heart: The pulmonic valve is between the right ventricle and the pulmonary artery, which carries blood to the lungs.
The aortic valve is between the left ventricle and the aorta, which carries blood to the body. What Are the Parts of the Circulatory System? Two pathways come from the heart: The pulmonary circulation is a short loop from the heart to the lungs and back again.
The systemic circulation carries blood from the heart to all the other parts of the body and back again. The pulmonary artery is a big artery that comes from the heart. It splits into two main branches, and brings blood from the heart to the lungs. At the lungs, the blood picks up oxygen and drops off carbon dioxide. The blood then returns to the heart through the pulmonary veins. Next, blood that returns to the heart has picked up lots of oxygen from the lungs. So it can now go out to the body.
The aorta is a big artery that leaves the heart carrying this oxygenated blood. Branches off of the aorta send blood to the muscles of the heart itself, as well as all other parts of the body. Like a tree, the branches gets smaller and smaller as they get farther from the aorta.
At each body part, a network of tiny blood vessels called capillaries connects the very small artery branches to very small veins. The capillaries have very thin walls, and through them, nutrients and oxygen are delivered to the cells. Waste products are brought into the capillaries.
Capillaries then lead into small veins. Small veins lead to larger and larger veins as the blood approaches the heart. Valves in the veins keep blood flowing in the correct direction. Two large veins that lead into the heart are the superior vena cava and inferior vena cava.
They were interested in participants that may have subclinical heart problems i. Once they had excluded participants with cardiovascular disease from their analyses, the relationship between cardiac index and brain volume remained, although there was no association between cardiac index and heart ventricle size. The researchers suggested that a higher cardiac index reflected a better functioning heart. They compared participants whose cardiac indices were in the top third to participants who were in the middle third and the bottom third.
They found that participants in the middle third and the bottom third had smaller brain volume than the people in the top third. Participants with low cardiac indices less than 2. They found that association between cardiac index and brain volume was stronger in those under the age of 60 compared to older adults, and was also stronger in men than in women.
How did the researchers interpret the results?
Sample 1: Heart and Lung Diagram
The researchers say that, even in the absence of cardiovascular disease, cardiac index is related to brain volume. They suggest that reduced body blood flow may contribute to subclinical brain injury by the disruption to brain blood flow mechanisms.
Conclusion This relatively large cross-sectional study found an association between a low cardiac index and smaller brain volume.
However, a low cardiac index, and the associated reduction in brain volume, did not seem to have a strong effect on brain function. Also, as a cross-sectional analysis thatonly examines factors at a single point in time, it cannot demonstrate causation between cardiac function and the physiological signs of brain ageing assessed here.
There are some further limitations of this research that need to be considered, some of which the researchers have highlighted: