<prompt> Earliest feature of pulmonary venous hypeension is -Upper lobar vessel dilatationKerley B LinesLeft atrial enlargementPleural effusion  <response>: Upper lobe venous diversion is the 1st radiological sign of pulmonary venous hypeension.Kerley B Lines , perihilar haze ,peribronchial cuffing,pumonary ossicles ,fine punctuate calcification and perihilar batwing pattern are the other features seen in PVH. 