Factors in favour of SVT versus sinus tachycardia in pediatrics in clude the following EXCEPT

(D). In sinus tachycardia, the history and onset are consistent with a known cause of tachycardia, such as fever or dehydration and P waves are consistently present, are of normal morphology, and occur at a rate that varies somewhat. ln SVT, onset is often abrupt without prodrome and P waves are absent or polymorphic, and when present, their rate is often fairly steady at or above 220 beats/min. Poor perfusion can present in either causes as in dehydration with tachycardia and in late stage of SVT