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What is Electrical alternans is seen in - and explain in detail?
Electrical alternans is an electrocardiac 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 effusion and is thought to be related to changes in the ventricular electrical axis due to fluid in the pericardium , as the hea essentially wobbles in the fluid filled pericardial sac . Ref Harrison 20,th edition pg 1543