<prompt> Electric altemans is seen in:Cardiac tamponadeRestrictive cardiomyopathyConstructive pericarditisRight Ventricular MI RVMI  <response>: Answer is A Cardiac tamponade Electrical alternans refers to a beat-to-beat alteration in one or more components of the ECG signal. Total electrical alternans P-QRS-T with sinus tachycardia is a relatively specific sign for pericardial effusion, often with cardiac tamponade. Feature Cardiac Tamponade Constrictive Pericarditis Restrictive Cardiomyopathy RVMI Electrical Alternans May be present Absent Absent Absent 