A novel snare assistance safeguards against early embolization of devices and facilitates quick retrieval of malpositioned devices in atrial septal defects with deficient margins

摘要

Background: Embolization might complicate device closure of large atrial septal defects (ASDs) with deficient margins. When margins are deficient, a precariously placed device can appear to be held in good position by the rigid delivery cable. Once the cable is unscrewed, the device adopts the natural lie of the interatrial septum. This can occasionally expose the inadequately captured margins and lead to device embolization. Most embolizations occur immediately after release. Retrieval of the embolized device required prolonged fluoroscopy and sometimes open heart surgery. Objective: To evolve a new strategy of retrieval of a malpositioned device after unscrewing the cable before impending embolization. Materials and Methods: After deploying the device in place, a snare is passed through the delivery sheath around the cable to grip the screw on the right atrial disc of the device. With the snare holding the screw end, the device is released by unscrewing the cable. The device position is reconfirmed on echocardiography. The snare is subsequently removed if the device was stable. In case of device migration, the same snare is used to retrieve the device before it embolizes completely. Results: Snare assistance was used in 24 patients considered as high-risk for device embolization. Its usefulness was demonstrated in two patients with deficient posterior margin and small inferior margin where the device got malpositioned immediately after release. As the snare was still holding on to the screw end, the device could be retrieved into the sheath easily. Conclusion: This novel snare assisted device release strategy safeguards against device embolization in large ASDs with deficient rims and allows simplified retrieval.