The MB score: a new risk stratification index to predict the need for advanced tools in lead extraction procedures

Aims A validated risk stratification schema for transvenous lead extraction (TLE) could improve the management of these procedures. We aimed to derive and validate a scoring system to efficiently predict the need for advanced tools to achieve TLE success. Methods and results Between November 2013 and March 2018, 1960 leads were extracted in 973 consecutive TLE procedures in two national referral sites using a stepwise approach. A procedure was defined as advanced extraction if required the use of powered sheaths and/or snares. The study population was a posteriori 1:1 randomized in derivation and validation cohorts. In the derivation cohort, presence of more than two targeted leads (odds ratio [OR] 1.76, P = 0.049), 3-year-old (OR 3.04, P = 0.001), 5-year-old (OR 3.48, P < 0.001), 10-year-old (OR 3.58, P = 0.008) oldest lead, implantable cardioverter-defibrillator (OR 3.84, P < 0.001), and passive fixation lead (OR 1.91, P = 0.032) were selected by a stepwise procedure and constituted the MB score showing a C-statistics of 0.82. In the validation group, the MB score was significantly associated with the risk of advanced extraction (OR 2.40, 95% confidence interval 2.02-2.86, P < 0.001) and showed an increase in event rate with increasing score. A low value (threshold = 1) ensured 100% sensibility and 100% negative predictive value, while a high value (threshold = 5) allowed a specificity of 92.8% and a positive predictive value of 91.9%. Conclusion In this study, we developed and tested a simple point-based scoring system able to efficiently identify patients at low and high risk of needing advanced tools during TLE procedures.