Radiographic and electrocardiography-gated noncontrast cardiac CT assessment of lead perforation: modality comparison and interobserver agreement.

BACKGROUND: Pacemaker or implantable cardioverter-defibrillator lead extraction may be required because of infection, malfunction, or breakage. The preprocedural identification of lead tip position may help ensure safe performance of the procedure. OBJECTIVE: To analyze the ability of chest radiography and CT imaging to characterize lead tip position and identify perforation in a population of patients who underwent lead extraction. METHODS: Among patients who underwent lead extraction between November 2008 and April 2011, a nonrandom subset of 50 patients with 116 leads was selected for retrospective analysis. All patients had undergone chest radiography and thin-section electrocardiography-gated noncontrast cardiac CT. Two radiologists independently evaluated the imaging studies, using oblique multiplanar image reconstruction techniques for the CT examinations. Beam hardening artifacts were graded (0-3). Likelihood of perforation on each imaging study was graded on a 5-point scale. RESULTS: Among 116 leads, 17 were identified as perforated on CT, 12 leads were equivocal, and 87 were not perforated. Interobserver agreement for CT perforation vs nonperforation was good (κ = 0.71); weighted kappa for the entire 5-point scale was moderate (κ = 0.54). Beam hardening artifacts were common, with a mean value of 2.1. The 2 observers identified perforation on chest radiography with an average sensitivity of 15% compared with CT. The 2 observers did not agree on any cases of chest radiographic perforation (κ = -0.1). CONCLUSION: Electrocardiography-gated noncontrast cardiac CT imaging with oblique multiplanar analysis can identify potential lead perforation with a moderate-to-good level of interobserver agreement. Chest radiography demonstrates poor sensitivity and interobserver agreement compared with CT.