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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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A 62 years old man with carcinoma of lung presented to emergency depament with respiratory distress. His EKG showed electrical alternans. The most likely diagnosis is
assistant
The correct answer is  Electrical alternans is an electrocardiographic phenomenon of alternation of QRS complex amplitude or axis between beats and a possible wandering base-line. It is seen in cardiac tamponade and severe pericardial effusionMassive pericardial effusion produces a triad of:Low QRS voltageTachycardiaElectrical alternansRef: Harrison's 18/e p1972