A multiple modality imaging system 10 for cardiac imaging includes an x-ray scanner 24,30 which acquires contrast enhanced CT projection data of coronary arteries with a laterally offset flat panel detector and a SPECT imaging scanner 40a,40b, which shares the same examination region and gantry as the x-ray scanner, acquires nuclear projection data of the coronary arteries. A CT reconstruction processor 34 generates a 3D coronary artery image representation, at least one planar coronary artery angiogram, and a 3D attenuation correction map from the acquired CT projection data. A SPECT reconstruction processor 44 corrects the acquired nuclear projection data based on the generated attenuation correction map and generates a SPECT image representation of the coronary arteries from the corrected nuclear projection data. A fusion processor 54 combines the nuclear image representation, the 3D vessel image representation, and the at least one planar vessel angiogram into a composite image.
