title: Radiofrequency ablation of premature ventricular ectopy improves the efficacy of cardiac resynchronization therapy in nonresponders.
abstract: OBJECTIVE
  This study sought to examine whether suppressing premature ventricular contractions (PVC) using radiofrequency ablation improves effectiveness of the cardiac resynchronization therapy (CRT) in nonresponders.
  
  
  BACKGROUND
  CRT is an effective strategy for drug refractory congestive heart failure. However, one-third of patients with CRT do not respond clinically, and the causes for nonresponse are poorly understood. Whether frequent PVC contribute to CRT nonresponse remains unknown.
  
  
  METHODS
  In this multicenter study, CRT nonresponders with >10,000 PVC in 24 h who underwent PVC ablation were enrolled from a prospective database.
  
  
  RESULTS
  Sixty-five subjects (age 66.6 ± 12.4 years, 78% men, QRS duration of 155 ± 18 ms) had radiofrequency ablation of PVC from 76 foci. Acute and long-term success rates of ablation were 91% and 88% in 12 ± 4 months of follow-up. There was significant improvement in left ventricular (LV) ejection fraction (26.2 ± 5.5% to 32.7 ± 6.7 %, p < 0.001), LV end-systolic diameter (5.93 ± 0.55 cm to 5.62 ± 0.32 cm, p < 0.001), LV end-diastolic diameter (6.83 ± 0.83 cm to 6.51 ± 0.91 cm, p < 0.001), LV end-systolic volume (178 ± 72 to 145 ± 23 ml, p < 0.001), LV end-diastolic volume (242 ± 85 ml to 212 ± 63 ml, p < 0.001), and median New York Heart Association functional class (3.0 to 2.0, p < 0.001). Modeling of pre-ablation PVC burden revealed an improvement in ejection fraction when the pre-ablation PVC burden was >22% in 24 h.
  
  
  CONCLUSIONS
  Frequent PVC is an uncommon yet significant cause of CRT nonresponse. Radiofrequency ablation of PVC foci improves LV function and New York Heart Association class and promotes reverse remodeling in CRT nonresponders. PVC ablation may be used to enhance CRT efficacy in nonresponders with significant PVC burden.
authors.affiliation: Division of Cardiovascular Diseases, Cardiovascular Research Institute, University of Kansas Hospital and Medical Center, Kansas City, Kansas 66160-7200, USA. dlakkireddy@mac.md
authors.forename: Dhanunjaya
authors.initials: D
authors.lastname: Lakkireddy
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Biase
authors.forename: Kay
authors.initials: K
authors.lastname: Ryschon
authors.forename: Mazda
authors.initials: M
authors.lastname: Biria
authors.forename: Vijay
authors.initials: V
authors.lastname: Swarup
authors.forename: Yeruva Madhu
authors.initials: YM
authors.lastname: Reddy
authors.forename: Atul
authors.initials: A
authors.lastname: Verma
authors.forename: Sudharani
authors.initials: S
authors.lastname: Bommana
authors.forename: David
authors.initials: D
authors.lastname: Burkhardt
authors.forename: Raghuveer
authors.initials: R
authors.lastname: Dendi
authors.forename: Antonio
authors.initials: A
authors.lastname: Dello Russo
authors.forename: Michela
authors.initials: M
authors.lastname: Casella
authors.forename: Corrado
authors.initials: C
authors.lastname: Carbucicchio
authors.forename: Claudio
authors.initials: C
authors.lastname: Tondo
authors.forename: Buddhadeb
authors.initials: B
authors.lastname: Dawn
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy; D017115:Catheter Ablation; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018879:Ventricular Premature Complexes / Q000000981:diagnostic imaging / Q000601:surgery*