title: Interventricular lead separation is critical for NT-proBNP reduction after cardiac resynchronization therapy.
abstract: OBJECTIVE
  Effective cardiac resynchronization therapy may depend upon the distance between left ventricular (LV) and right ventricular (RV) pacing leads. We assessed the influence of lead separation upon circulating NT-proBNP.
  
  
  METHODS
  In total, 132 patients underwent assessment, including NT-proBNP assay, before and after cardiac resynchronization therapy. 3D lead separation was calculated from postero-anterior and lateral chest radiography.
  
  
  RESULTS
  Lead separation correlated with NT-proBNP reduction (r = 0.25; p = 0.004). Circulating NT-proBNP only fell in those with lead separation in the upper two quartiles. Deteriorating NT-proBNP occurred in 44 patients. Lead separation was less in these patients compared with those with an improvement (corrected 3D lead separation: 148.0 ± 5.38 and 170.5 ± 4.21 mm, respectively; p = 0.0018).
  
  
  CONCLUSIONS
  Left ventricular-right ventricular lead separation correlates with postcardiac resynchronization therapy improvements in circulating NT-proBNP, a powerful marker of heart failure status and prognosis. Attention should be paid to achieving maximal lead separation at implantation.
authors.affiliation: Scottish Advanced Heart Failure Service, Golden Jubilee National Hospital, Agamemnon Street, Clydebank, Glasgow, G81 4DY, UK.
authors.forename: Ninian N
authors.initials: NN
authors.lastname: Lang
authors.forename: Athar A
authors.initials: AA
authors.lastname: Badar
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Pettit
authors.forename: Sheena
authors.initials: S
authors.lastname: Templeton
authors.forename: Derek T
authors.initials: DT
authors.lastname: Connelly
authors.forename: Roy S
authors.initials: RS
authors.lastname: Gardner
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy; D058409:Cardiac Resynchronization Therapy Devices; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D012189:Retrospective Studies
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: NT-proBNP; cardiac resynchronization therapy; heart failure; lead separation