title: Changes in electrical dyssynchrony by body surface mapping predict left ventricular remodeling in patients with cardiac resynchronization therapy.
abstract: Electrical activation is important in cardiac resynchronization therapy (CRT) response. Standard electrocardiographic analysis may not accurately reflect the heterogeneity of electrical activation.
  
  
  
  We compared changes in left ventricular size and function after CRT to native electrical dyssynchrony and its change during pacing.
  
  
  
  Body surface isochronal maps using 53 anterior and posterior electrodes as well as 12-lead electrocardiograms were acquired after CRT in 66 consecutive patients. Electrical dyssynchrony was quantified using standard deviation of activation times (SDAT). Ejection fraction (EF) and left ventricular end-systolic volume (LVESV) were measured before CRT and at 6 months. Multiple regression evaluated predictors of response.
  
  
  
  ∆LVESV correlated with ∆SDAT (P = .007), but not with ∆QRS duration (P = .092). Patients with SDAT ≥35 ms had greater increase in EF (13 ± 8 units vs 4 ± 9 units; P < .001) and LVESV (-34% ± 28% vs -13% ± 29%; P = .005). Patients with ≥10% improvement in SDAT had greater ∆EF (11 ± 9 units vs 4 ± 9 units; P = .010) and ∆LVESV (-33% ± 26% vs -6% ± 34%; P = .001). SDAT ≥35 ms predicted ∆EF, while ∆SDAT, sex, and left bundle branch block predicted ∆LVESV. In 34 patients without class I indication for CRT, SDAT ≥35 ms (P = .015) and ∆SDAT ≥10% (P = .032) were the only predictors of ∆EF.
  
  
  
  Body surface mapping of SDAT and its changes predicted CRT response better than did QRS duration. Body surface mapping may potentially improve selection or optimization of CRT patients.
authors.affiliation: United Heart & Vascular Clinic, St. Paul, Minnesota.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Gage
authors.affiliation: University of Minnesota, Minneapolis, Minnesota.
authors.forename: Antonia E
authors.initials: AE
authors.lastname: Curtin
authors.affiliation: United Heart & Vascular Clinic, St. Paul, Minnesota.
authors.forename: Kevin V
authors.initials: KV
authors.lastname: Burns
authors.affiliation: Medtronic plc, Mounds View, Minnesota.
authors.forename: Subham
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Medtronic plc, Mounds View, Minnesota.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Gillberg
authors.affiliation: United Heart & Vascular Clinic, St. Paul, Minnesota; University of Minnesota, Minneapolis, Minnesota,. Electronic address: alan.bank@allina.com.
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Bank
mesh_terms: D000368:Aged; D018780:Body Surface Potential Mapping; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000379:methods; D058409:Cardiac Resynchronization Therapy Devices; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D018579:Patient Selection; D058996:Quality Improvement; D013318:Stroke Volume; D020257:Ventricular Remodeling
keywords: Body surface mapping; Cardiac resynchronization therapy; Electrocardiography; Heart failure; Response