Abstract Body (Do not enter title and authors here): Background
A history of prior sternotomy has been debated as either a protective factor or a risk for worse outcomes in patients undergoing transvenous lead extraction (TLE). The safety and efficacy of extraction in this population remain incompletely explored.

Objective
To evaluate the impact of previous sternotomy on procedural outcomes, including complication and success rates, in patients undergoing TLE.

Methods
From a prospectively maintained registry, we included all patients undergoing TLE at our center between 1996 and 2022. Patients were categorized into 2 groups based on previous sternotomy history. Baseline characteristics, procedural outcomes, and safety profiles were compared between groups. Logistic regression was performed to identify independent predictors of major complications.

Results
Among 4,846 patients undergoing TLE, 1344 (27.7%) had a history of previous sternotomy. These patients were older (69.67±10.96 vs. 61.70 ±16.44 years, p<0.001), predominantly male (80.4% vs. 64.1%, p<0.001), and had a higher prevalence of comorbidities and an infectious indication for extraction (Table 1). Despite this, the sternotomy group had significantly lower major complication rate (1.6% vs. 2.8%, p=0.02), particularly cardiovascular lacerations (1.0% vs.1.9%, p=0.03). Among patients with major complications, rates of pericardial effusion requiring intervention were comparable (0.4% vs.1.2%, p=0.09), while the need for open heart surgery was significantly lower in the sternotomy group (0.7% vs.1.6%, p= 0.001). However, mortality during rescue cardiac surgical interventions was higher in the sternotomy group (33.3% vs.14.3%). Although not statistically significant (p=0.15), this underscores the importance of ensuring surgical backup and recognizing these patients as a high-risk group. Procedural and clinical success rates were significantly higher among the sternotomy group (Table 2). On multivariable logistic regression (Fig.1), lead age >10y and the presence of an ICD system were independent predictors of major complication. History of sternotomy was associated with lower odds of major complications (OR=0.62, 95%CI 0.38-1.01), although this did not reach statistical significance (p=0.05) .

Conclusion
Despite higher comorbidity burden, patients with prior sternotomy undergoing TLE showed a trend towards lower major complications and achieved higher success rates. This data highlights prior sternotomy's potential protective effect from major complications.