In the present invention, a method and associated system is provided that produces a new sequence of combined X-ray/fluoro images obtained in synchrony with intravascular dataset/images. This synchronization is based on the time tags recorded at the acquisition of one dataset of the X-ray/fluoroscopic images and the intravascular images/datasets and the cardiac cycle correspondence between the combined X-ray/fluoro datasets/images. The combined X-ray/fluoro and intravascular sensor images provided in the method for each position of intravascular measurement/slice along the blood vessel allows the physician the ability to determine the planned position of the treatment, e.g., a stent, in the X-ray/fluoro images based on the intravascular images, and allows an accurate assessment of the target/lesion location in the X-ray/fluoro images during treatment.