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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Cannon ‘a’ wave in venous waveform is suggestive of
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The correct answer is  The venous waveform is divided into several distinct peaks. The 'a' wave reflects right atrial presystolic contraction and occurs just after the electrocardiographic P wave, preceding the first heart sound (S). A prominent 'a' wave is seen in patients with reduced right ventricular compliance; cannon 'a' wave occurs with atrioventricular (AV) dissociation