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What is A wave in JVP is absent in: and explain in detail?
Ans. (a) Atrial fibrillationRef: Harrison 19th ed. /1443-1444* A wave in JVP is due to atrial contraction. In atrial fibrillation, since the atria are twitching, the power of atria is reduced to a level that a wave would be absent.* Heart block will have large a waves.* Tricuspid Regurgitation has absent x and large v waves.* Constrictive Pericarditis has a large y descent.