title: Detection of high incidence of Riata lead breaches by systematic postero-anterior and lateral chest X-ray in a large cohort.
abstract: OBJECTIVE
  Insulation breaches with externalization of conductor cables have been described for St-Jude Medical Riata™ defibrillation leads. Published data on the incidence of Riata lead abnormalities are quite heterogeneous. The objective of this study was to estimate systematically the prevalence of lead abnormalities using a postero-anterior (PA) and lateral chest X-ray (CXR).
  
  
  RESULTS
  From 2002 to 2008, 552 Riata defibrillation leads were implanted at our centre. We evaluated patients for potential insulation breaches. A PA and lateral CXR was obtained. Chest X-rays were reviewed by two electrophysiologists using a zooming function with magnification up to factor 7.5 and were classified as normal or abnormal for the presence of conductor externalization. A total of 284 patients were included. Riata lead models were 1570, 1580, 1582, 1590, 1592, 7000, 7002, and 7022. The total frequency of radiological lead defects was 24.3%. Insulation breaches occurred at zones of major lead curvature. Mean maximal spacing between extruding lead components was 3.6 ± 1.9 mm (range 2.0-12.4). Abnormal CXRs were more frequent in 8F leads (31.4% vs. 6.3%; P < 0.001). Most defects occurred with lead models 1582 (41.2%) and 1580 (31.4%). Mean time since implantation was longer in abnormal leads (6.7 vs. 5.9 years; P < 0.001). Abnormal leads had higher pacing thresholds (1.1 ± 0.8 V vs. 0.9 ± 0.4 V; P = 0.02).
  
  
  CONCLUSIONS
  The incidence of insulation breach in Riata leads is much higher than quoted by the manufacturer or reported by most of the literature. A PA and lateral CXR with zooming appears adequate to identify lead breaches when reviewed by an electrophysiologist. Riata lead breaches without electrical abnormalities present a management dilemma and will require further studies.
authors.affiliation: Division of Electrophysiology,  Quebec Heart and Lung Institute, Affiliated to Laval University, 2725, Chemin Sainte-Foy, Quebec G1V 4G5,  Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Steinberg
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Sarrazin
authors.forename: François
authors.initials: F
authors.lastname: Philippon
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Bouchard
authors.forename: Gilles
authors.initials: G
authors.lastname: O'Hara
authors.forename: Franck
authors.initials: F
authors.lastname: Molin
authors.forename: Isabelle
authors.initials: I
authors.lastname: Nault
authors.forename: Louis
authors.initials: L
authors.lastname: Blier
authors.forename: Jean
authors.initials: J
authors.lastname: Champagne
mesh_terms: D015331:Cohort Studies; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011792:Quebec; D013902:Radiography, Thoracic