Rv enlarged on echo,i have 1 papvr but,mayo is telling,me it's not,hemodynamically significant? what else could be causing this? isn't it obvious?

No it isn't.: First, these are Numerical data that I can't see, but Mayo can. Suppose the RV enlargement is 1% above normal; suppose the PAPVR flow rate is one teaspoon a month. Then, if the numbers are teeny-weeny, not significant. Then, there's the question of factors like smoking/lung disease that could overwhelm all other factors. (AVB, rv enlarge often related, btw).