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Electrical alternans i.e., beat to beat of variation of QRS amplitude has been classically described in pericardial tamponade. Rarely, alternative causes are found in patients with QRS alternans. We report a case of atypical electrical alternans in a middle-aged female in the absence of pericardial effusion. A careful analysis of QRS complexes in our case suggested a unique pattern of alternans varying with respiratory movements instead. On evaluation, we found large left sided pleural effusion as the key underlying mechanism of the atypical alternans.