There are disclosed embodiments for a medical system capable of providing an external trigger signal. The medical system comprises at least one of an ECG signal providing unit to provide an ECG signal indicative of an electrical change in a target object, a reference signal providing unit to provide at least one reference signal for triggering an operation of the medical system, and a medical image providing unit to provide a medical image of the target object. The medical system may further comprise a processor to form an external trigger signal using at least one of the ECG signal, reference signal and medical image. The medical system may further comprise a signal interface unit to transmit the external trigger signal to an external device coupled to the medical system.
