1. A method of generating a medical image of a medical instrument inserted into a moving examination area of a patient, the method comprising: recording a three-dimensional image data set of the examination area before inserting the medical instrument into the examination area; assigning ECG data to the three-dimensional image data set such that the three-dimensional image data set is divided into a plurality of movement phases and corresponding time intervals; recording a current two-dimensional fluoroscopic image of the examination area; recording current ECG data of the patient data while recording the current two-dimensional fluoroscopic image; registering the three-dimensional image data set with the current two-dimensional fluoroscopic image using the current ECG data of the patient; and reconstructing a three-dimensional reconstruction image of the moving examination area using the three-dimensional image data set registered with the current two-dimensional fluoroscopic image such that the three-dimensional reconstruction image corresponds to and represents the movement phases of the examination area, the three-dimensional reconstruction image having a first coordinate system, wherein the current ECG data are continuously recorded while the medical instrument is inserted into the examination area, the three-dimensional reconstruction image of the moving examination area is displayed using the current ECG data as trigger signals, current position data of the medical instrument are continuously acquired while the medical instrument is inserted into the examination area using a navigation system, the current position data having a second coordinate system registered with the first coordinate system, and the medical instrument is displayed within the display of the three-dimensional reconstruction image using the current position data, the display of the medical instrument continuously representing a current position of the medical instrument relative to the moving examination area.