Patent ID: 8358734

Claim:
An X-ray computed tomographic apparatus comprising: a gantry including an X-ray tube which generates X-rays and an X-ray detector which detects X-rays transmitted through a subject to be examined; a tomogram generating unit which generates tomogram data on the basis of an output from the X-ray detector; a cardiac index calculating unit which instantly calculates a plurality of cardiac indexes associated with a heartbeat state on the basis of an electrocardiogram associated with the subject; a cardiac index selection unit which selects at least one cardiac index among the plurality of calculated cardiac indexes in accordance with a user instruction; a display unit which is held on a housing of the gantry directly or through an arm and instantly displays the selected cardiac index and at the same time displays an instruction to the subject, and an operation window generating unit which generates an operation window for selection of the cardiac index and design of a display layout, wherein the operation window includes an electrocardiographic area in which the user can select the at least cardiac index for display and a second area for display of information corresponding to progress of examination as selected by the user, and the operation window generating unit is operable by the user to control the display layout of the electrocardiographic area and the second area.