title: Don't expect left ventricular reverse remodeling after cardiac resynchronization therapy in patients with systolic heart failure and atrioventricular block: A multicenter study.
abstract: BACKGROUND
  The BLOCK HF trial showed that heart failure patients with atrioventricular block (AVB) and left ventricular systolic dysfunction (LVSD) are considered good candidates for cardiac resynchronization therapy (CRT), even though they have a narrow QRS duration. We aimed to compare the clinical response to CRT between patients with AVB combined with LVSD and patients with pre-existing CRT indications.
  
  
  METHODS
  We compared the clinical data on CRT across the following 3 groups in 3 cardiovascular centers; heart failure patients with an LV ejection fraction (LVEF) of ≤35% who had a QRS duration of ≥120ms (standard indication, n=125), those needing an upgrade to CRT (upgrade, n=49), and patients with an LVEF of ≤50% who had advanced AVB (AVB with LVSD, n=27).
  
  
  RESULTS
  The prevalence of left bundle branch block differed significantly across the groups (87.2%, 98.0% and 40.7%; P<0.001). No inter-group difference was found in the percentage of patients in whom clinical composite score (CCS) assessed 6months after the CRT was improved (60.8%, 57.1% and 70.4%; P=0.67). Whereas, even among the patients with an improved CCS, a significantly smaller LV end-systolic volume reduction after the CRT was seen in the ABV with LVSD group (-35.3±34.7, -21.4±28.5 and -5.2±23.9%; P=0.001). The incidence of cardiovascular death or hospitalization from heart failure within 5years occurred with a similar frequency (44%, 55.1% and 44.4%; P=0.9).
  
  
  CONCLUSIONS
  As compared to patients with preexisting CRT indications, CRT may be similarly effective for patients with AVB and LVSD, however, LV reverse remodeling may be uncommon among them.
authors.affiliation: Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan. Electronic address: rjrgw059@ybb.ne.jp.
authors.forename: Akinori
authors.initials: A
authors.lastname: Sairaku
authors.affiliation: Department of Cardiology, Cardiovascular Center, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466-8650, Japan. Electronic address: ykyoshi@wb3.so-net.ne.jp.
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nakano
authors.affiliation: Department of Cardiology, Cardiovascular Center, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466-8650, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Hirayama
authors.affiliation: Department of Cardiology, Cardiovascular Center, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466-8650, Japan.
authors.forename: Mayuho
authors.initials: M
authors.lastname: Maeda
authors.affiliation: Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan; Department of Cardiology, Hiroshima City Hospital, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Hashimoto
authors.affiliation: Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Kihara
mesh_terms: D000368:Aged; D054537:Atrioventricular Block / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000379:methods; D004452:Echocardiography / Q000379:methods; D005260:Female; D054143:Heart Failure, Systolic / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000503:physiopathology / Q000517:prevention & control*; D016896:Treatment Outcome; D020257:Ventricular Remodeling / Q000502:physiology*
keywords: Atrioventricular block; Cardiac resynchronization therapy; Left ventricular systolic dysfunction; Reverse remodeling; Standard indication; Upgrade