Document resource
Background Implantable loop recorders (ILRs) are widely utilised for rhythm monitoring. However, there is limited evidence regarding imaging-guided techniques, especially among patients with breast implants. The significantly reduced subcutaneous space has been underestimated and often not recognised within this group presenting a high risk of device migration into the capsule. Herein, we report a series of four cases with cosmetic implants that underwent ILR insertion under ultrasound guidance.Methods We retrospectively reviewed four consecutive patients with bilateral breast implants who underwent ILR implantation between October 2024 and October 2025. Pre-procedural high-frequency ultrasound was performed using a linear-array transducer to delineate the implant capsule adjacent to potential sites of device insertion and to measure the subcutaneous tissue distance. Skin markings were applied to define a safe insertion tract ( figure 1) and ensure adequate distance between the device tip and implant capsule. ILRs were inserted under local anaesthesia by a cardiologist. The devices were introduced perpendicular to the left sternal border (instead of the conventional 45° or parasternal trajectory) along the marked skin track, crucially maintaining a safe margin above the implant capsule. Post-deployment ultrasound confirmed device position and separation from the implant (figure 2). Patients were followed up by the pacing clinic.Results All four patients underwent successful ILR implantation without intraoperative or acute postoperative complications. Pre-procedural ultrasound-assisted mapping enabled accurate placement of each device in the space between the sternum and the implants. No contact with the implant occurred during or after insertion. At ≥3 months follow-up, no device migration or implant rupture was observed. ILR sensing was satisfactory in all cases. One patient demonstrated sinus bradycardia with pauses up to 4.5 seconds, while the remaining devices recorded no significant arrhythmias during follow-up.Conclusion Ultrasound-guided ILR insertion technique should be considered mandatory to maintain procedural safety and accuracy in patients with breast implants undergoing implantable loop recorder implantation. By analysing a series of implant vectors, we identified the challenges in avoiding the implant capsule, which extends far more superiorly and medially than predicted. We have demonstrated a potential hazard due to the short distance between the device and the capsule in the conventional approaches. This represents unseen challenge, and information is sparse in the current literature. Further reports and larger series are needed to reinforce best techniques to guide optimal implant technique and a safer practice.Abstract 449 Figure 2A post insertion sonogram showing separation of the implanted device from the breast implantAbstract 449 Figure 1Skin Markings depicting implant capsule and two potential mapped ILR insertion tracks.