title: Standard chest radiograph predicts left ventricular lead location in chronic resynchronization therapy patients more accurately than intraoperative fluoroscopy.
abstract: BACKGROUND
  Targeting the proper left ventricular lead site is important in cardiac resynchronization therapy (CRT) procedures, as suboptimal lead locations may result in a lack of clinical response. Left ventricular lead locations are typically confirmed using fluoroscopy (fluoro) with AP, RAO, and LAO orientations. However, standard fluoro may inadequately delineate true left ventricular lead locations, due to insufficient angulation or extreme cardiac rotation. Posteroanterior and lateral chest radiograph (CXRPAL), performed routinely to verify lead stability and freedom from complication, may better confirm left ventricular lead location due to utilization of a straight lateral view.
  
  
  OBJECTIVE
  Compared to fluoro, lead localization using CXRPAL will be more predictive of true left ventricular lead location in CRT patients.
  
  
  METHODS
  Of 252 medically optimized CHF patients who underwent CRT implantation by multiple operators from October 2001 to August 2011, 46 (mean age, 58.9 ± 13.2 years; 10 female; 19 ICM; 19 LBBB; mean ejection fraction, 26.6 ± 8.9 %; mean QRS width, 144.4 ms) had CT scanning performed as part of routine medical care and comprise this study. Operative reports of left ventricular lead location by fluoro were reviewed. Left ventricular lead location was identified on CXRPAL by three independent observers blinded to operative results. Left ventricular lead locations according to fluoro and CXRPAL were correlated with CT scan at a mean follow-up of 57.6 ± 28.8 months (Tables 1 and 2).
  
  
  RESULTS
  Compared to standard fluoro, CXRPAL agreed better with CT scan (κ = 0.413 fluoro vs. κ = 0.864 CXRPAL on the vertical axis, and κ = 0.086 fluoro vs. κ = 0.864 CXRPAL on the horizontal axis) for identification of left ventricular lead location.
  
  
  CONCLUSIONS
  In this small study of 46 CRT patients, interpretation of left ventricular lead location using CXRPAL correlated better with true lead location identified on CT scan, compared to standard fluoroscopy. Use of a steep lateral view during CRT implantation may be necessary to accurately identify left ventricular lead locations.
authors: Cardiac Electrophysiology Program, Division of Cardiology, Department of Medicine, University of California, San Diego, CA, USA.
authors: Lu
authors: L
authors: Chen
authors: Jay E
authors: JE
authors: Tiongson
authors: Sebastian
authors: S
authors: Obrzut
authors: Martin B
authors: MB
authors: McDaniel
authors: Hsin-Yi
authors: HY
authors: Chang
authors: Jigar
authors: J
authors: Patel
authors: Paul J
authors: PJ
authors: Friedman
authors: Gregory K
authors: GK
authors: Feld
authors: Ulrika M
authors: UM
authors: Birgersdotter-Green
mesh_terms: D058406:Cardiac Resynchronization Therapy; D016009:Chi-Square Distribution; D004567:Electrodes, Implanted; D005260:Female; D005471:Fluoroscopy; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D013902:Radiography, Thoracic / Q000592:standards*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed