An apparatus for medical imaging, comprising: an X-ray unit having an image intensifier and an adjustable collimator, the X-ray unit operative for transmitting X-ray emissions via the collimator to an area of interest in a heart of a subject; an image processor, receiving X-ray image data from the X-ray unit, and operative for generating a first set of temporally separated images of the area of interest by processing the X-ray image data; a cardiac imaging system, operative for generating electroanatomic maps of the heart and positional information of a cardiac catheter introduced therein, the cardiac imaging system operative for generating a second set of temporally separated images from the area of interest, wherein the image processor and the cardiac imaging system are cooperative for performing the steps of: combining the first set and the second set to produce combined images of the area of interest; blocking the X-ray emissions from reaching the subject; updating the second set; combining the first set with the updated second set to produce updated combined images of the area of interest; displaying the updated combined images; when a predetermined condition is satisfied, iterating the steps of updating the second set, combining the first set with the updated second set and displaying the updated combined images; and when the predetermined condition is not satisfied discontinuing blocking the X-ray emissions from reaching the subject, and again performing the step of generating a first set to produce a new first set, and thereafter iterating the steps of blocking the X-ray emissions, updating, combining the first set with the updated second set using the new first set as the first set. an X-ray unit having an image intensifier and an adjustable collimator, the X-ray unit operative for transmitting X-ray emissions via the collimator to an area of interest in a heart of a subject; an image processor, receiving X-ray image data from the X-ray unit, and operative for generating a first set of temporally separated images of the area of interest by processing the X-ray image data; a cardiac imaging system, operative for generating electroanatomic maps of the heart and positional information of a cardiac catheter introduced therein, the cardiac imaging system operative for generating a second set of temporally separated images from the area of interest, wherein the image processor and the cardiac imaging system are cooperative for performing the steps of: combining the first set and the second set to produce combined images of the area of interest; blocking the X-ray emissions from reaching the subject; updating the second set; combining the first set with the updated second set to produce updated combined images of the area of interest; displaying the updated combined images; when a predetermined condition is satisfied, iterating the steps of updating the second set, combining the first set with the updated second set and displaying the updated combined images; and when the predetermined condition is not satisfied discontinuing blocking the X-ray emissions from reaching the subject, and again performing the step of generating a first set to produce a new first set, and thereafter iterating the steps of blocking the X-ray emissions, updating, combining the first set with the updated second set using the new first set as the first set. combining the first set and the second set to produce combined images of the area of interest; blocking the X-ray emissions from reaching the subject; updating the second set; combining the first set with the updated second set to produce updated combined images of the area of interest; displaying the updated combined images; when a predetermined condition is satisfied, iterating the steps of updating the second set, combining the first set with the updated second set and displaying the updated combined images; and when the predetermined condition is not satisfied discontinuing blocking the X-ray emissions from reaching the subject, and again performing the step of generating a first set to produce a new first set, and thereafter iterating the steps of blocking the X-ray emissions, updating, combining the first set with the updated second set using the new first set as the first set.