An interventional medical system (10) comprises an instrument (100) provided with a plug head (120) and a delivery cable (200) provided with a cable head (211), and further comprises a locking sleeve (300) movably sleeved onto the delivery cable (200). The cable head (211) comprises at least one resilient locking piece (123) extending approximately away from a central axis of the cable head (211). When under a radial restraint applied by the locking sleeve (300), the plug head (120) abuts the locking piece (123) such that the plug head (120) is connected to the cable head (211), and when the locking sleeve (300) has moved relative to the delivery cable (200) such that the locking piece (123) is no longer radially restrained, the locking piece (123) elastically moves away from the plug head (120) such that the instrument (100) is separated from the delivery cable (200).
