1. Examination apparatus for examination of an object of interest, the examination apparatus comprising: an acquisition unit ( 101 ) adapted for acquiring a series of projection images of the object of interest on the basis of a delayed acquisition trajectory; a determination unit ( 112 ) adapted for determining a first subtracted image and a second subtracted image on the basis of the series of projection images; wherein the determination unit ( 112 ) is further adapted for determining a cardiac phase for data reconstruction on the basis of the first subtracted image and the second subtracted image.