title: Suboptimal medical therapy in patients with systolic heart failure is associated with less improvement by cardiac resynchronization therapy.
abstract: BACKGROUND
  Proven medical therapy is under-prescribed in heart failure (HF) for various reasons. Cardiac resynchronization therapy (CRT) is of proven value in selected patients with HF; however, the degree of benefit in those without the optimal therapy is not clear.
  
  
  METHODS
  This is a retrospective study comparing the effect of CRT in 30 patients without optimal combination therapy (group 1; 10 (33%) without ACEi or equivalent and 25 (83%) without beta-blockers) to an age, sex, ejection fraction (EF) and New York Heart Association (NYHA) class matched control but with the combination (group 2; n=30) at baseline. All patients were in NYHA class III or IV with EF < or = 35% and QRS interval > or = 120 ms. Echocardiographic examination and N-terminal pro-brain natriuretic peptide (NT pro-BNP) levels before and 3 months after CRT were compared between the two groups. The composite endpoints of HF hospitalization or death during follow-up were compared by Kaplan-Meier analysis.
  
  
  RESULTS
  There were significantly less improvement in EF (+4.0+/-2.5% vs +10.1+/-3.2%; p<0.05) and degree of reverse remodeling in group 1 after 3 months. Patients in group 1 had significantly higher level of NT pro-BNP levels at 3 months (2221+/-2001 pg/mL vs 1038+/-905 pg/mL; p<0.001) and higher rates of HF hospitalization or death (53.3% vs 23.3%; Log rank chi2 5.52; p=0.019).
  
  
  CONCLUSIONS
  Patients receiving CRT but without optimal medical therapy were associated with less echocardiographic and clinical improvement. Optimal medical therapy, if tolerated, before CRT is necessary.
authors.affiliation: Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China. jwhfung@cuhk.edu.hk
authors.forename: Jeffrey W H
authors.initials: JW
authors.lastname: Fung
authors.forename: Joseph Y S
authors.initials: JY
authors.lastname: Chan
authors.forename: Leo C C
authors.initials: LC
authors.lastname: Kum
authors.forename: Hamish C K
authors.initials: HC
authors.lastname: Chan
authors.forename: Gabriel W K
authors.initials: GW
authors.lastname: Yip
authors.forename: Q
authors.initials: Q
authors.lastname: Zhang
authors.forename: Cheuk M
authors.initials: CM
authors.lastname: Yu
mesh_terms: D000368:Aged; D003131:Combined Modality Therapy; D004554:Electric Countershock; D005260:Female; D006333:Heart Failure / Q000188:drug therapy / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013599:Systole