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.