A method is disclosed for CT scanning a heart with a dual-source CT device including detectors of different widths in a system axis direction and for reconstruction of tomographic image data. In at least one embodiment, at least two circular scans are performed at different z positions and the spacing in the z direction is chosen such that at least two first scan zones are produced which are scanned by way of a circular scan with two detectors and at least one second scan zone is produced which is scanned twice by one detector in two successive circular scans, wherein a dual-source reconstruction is performed in the first scan zones and a two-segment reconstruction is performed in the at least one second scan zone and finally a common tomographic image data set is produced. Further, at least one embodiment is directed to a dual-source CT device in which the detectors have different widths in the system axis direction.