Troubleshooting in PM Leadless: How to manage an indissoluble knot

A 77‐year‐old patient, with permanent atrial fibrillation, underwent successful Micra transcatheter pacing system (MTPS) implantation. Once begun the pull‐back of the tether, an increasing resistance was felt by the operator until complete blockage. A challenging recapture of MTPS into the delivery system was performed. The retrieved MTPS showed an indissoluble knot close to the docking button that blocked the running of the tether, and a long clot inside the delivery system. The new design of internal handle components of MTPS recently updated seems to favor clot formation. We suggest a reconsideration of the standard recommendations about delivery system flushing and design of the inner flushing tube system.