ANATOMY
CHEST AND CARDIOVASCULAR
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -The right atrium has a relatively thin muscular wall and easily expands with blood as it fills (i.e., it is highly compliant). Because of its high compliance, the RA pressure is normally very low (0-3 mmHg).
Detailed explanation-2: -Normally the pressure on the right side of the heart and in the pulmonary arteries is lower than the pressure on the left side of the heart and in the aorta. This is because: the right side of the heart pumps blue (deoxygenated – little or no oxygen) blood returning from the body back to the lungs.
Detailed explanation-3: -The normal right-atrial pressure is 2–6 mmHg and is characterized by a and v waves and x and y descents (Fig. 2.4). The a wave represents the pressure rise within the right atrium due to atrial contraction and follows the P wave on the ECG by about 80 msec.