Abstract Body (Do not enter title and authors here): Introduction
Transvenous lead extraction (TLE) of old leads is associated with increased procedural complexity and risk due to the development of calcified vascular adhesions. This may necessitate additional tools to free the leads. Shockwave intravenous lithotripsy (IVL), which employs acoustic pressure waves to fracture calcified lesions, has emerged as an adjunctive tool in this setting. However, data on its feasibility in TLE remains limited.

Objective
To evaluate the feasibility of IVL as an adjunctive tool in complex TLE cases, focusing on the extraction tools utilized, fluoroscopy duration, success rates, and associated complications.

Methods
From a prospectively maintained registry, we analyzed all patients undergoing IVL-assisted TLE at our institution. These patients were matched to controls without IVL using propensity scores derived from baseline and procedural characteristics, including age, sex, infection indication, age of the oldest explanted lead, number of extracted leads, and number of extracted ICDs. A matching ratio of 1:3 was applied to increase statistical power while maintaining covariate balance.

Results
A total of 27 patients who underwent lithotripsy were successfully matched to 81 controls. The procedural characteristics are highlighted in Table 1. Mean number of extracted leads and mean age of the oldest extracted lead were comparable between the groups. Patients in the lithotripsy group had significantly higher utilization of laser sheaths alone or combined mechanical and laser sheaths. Median fluoroscopy time was significantly higher in the IVL group (50.2 vs.15.7 mins, p<0.001). Among 27 patients with IVL, complete shockwave applications were performed in 20 patients. In the remaining 7, applications were limited due to stenotic brachiocephalic or superior vena cava veins. Overall, the success and complication rates did not differ significantly between the groups (Fig.1, Table 2). Only one case of vascular laceration with perforation requiring intervention was recorded in the IVL group. The unexpectedly high complication and low success rates in the control group may in part be due to longer dwell times to match the IVL group.

Conclusion
We report the largest series on the use of shockwave IVL during complex TLE cases, with significantly higher fluoroscopy times indicating extended procedure durations. Despite favorable safety and efficacy outcomes, the complexity of lead removal remained evident, even with adjunctive IVL.