A method and system are disclosed for radiosurgical treatment of moving tissues of the heart, including acquiring at least one volume of the tissue and acquiring at least one ultrasound data set, image or volume of the tissue using an ultrasound transducer disposed at a position. A similarity measure is computed between the ultrasound image or volume and the acquired volume or a simulated ultrasound data set, image or volume. A robot is configured in response to the similarity measure and the position of the transducer, and a radiation beam is fired from the configured robot.