Abstract 18673: Fluoroscopy and High Voltage Testing - A Paradigm Shift in evaluation of Insulation Failure of Riata Lead

Abstract

Introduction: Current HRS guidelines for management of Riata lead recall are limited to close follow up. We have observed and reported high voltage testing (HVT) failure of Riata leads despite normal high resolution fluoroscopy (HRF) appearance and low voltage evaluation. We sought to assess the role of HRF and HVT to identify lead insulation defect. Methods: Patients with Riata leads were evaluated clinically and informed about the lead insulation issues. In addition to device interrogation, HRF examination and HVT testing were performed. Results: Out of 331 patients with Riata leads, 180 patients were seen in office. A total of 90 were screened with HRF and HVT. Separation of conductors was seen in 51% (46/90) and 9 % (8 patients) failed HVT (failed to induce/sense/shock VF). Out of 8 patients who failed HVT, 5 had normal HRF examinations. Retrospectively, additional 17 patients underwent lead extraction due to lead malfunction consistent with insulation failure. Lead extraction due to insulation defects were done in 36 /331 total pts and 19/90 screened patients (8 failed HVT, 8 patients for secondary prevention and externalized cables, 3 with externalized cables and on patient request). With 543 years of combined follow up(average 6 +1.3 years), prevalence of HRF detected insulation defect is 51% (46/90), 8.5%/year and malfunction consistent with insulation failure is 7.5% (25/331), 1.25%/year. Clinical examination, device interrogation, HRF and HVT has provided additional information and resulted in lead extractions in 19 patients (5 with normal and 14 with abnormal fluoroscopic appearance) despite of having normal low voltage parameters. Conclusions: Close follow up as suggested by HRS guidelines failed to identify high voltage integrity in 9% of patients. Additionally, 21% screened patients underwent lead extraction. These findings suggests the need of a larger prospective study incorporating the HRF and HVT to evaluate the integrity of Riata leads.