title: Usefulness of biventricular pacing to improve cardiac symptoms, exercise capacity and sympathetic nerve activity in patients with moderate to severe chronic heart failure.
abstract: BACKGROUND
  Although cardiac resynchronization using biventricular pacing (BVP) results in significant clinical improvement in patients with chronic heart failure (CHF), there is no evidence of improvement in sympathetic nerve activity (SNA).
  
  
  RESULTS
  Eighteen patients with CHF (dilated cardiomyopathy/ischemic cardiomyopathy =14/4) and left ventricular (LV) ejection fraction <40%, QRS duration >160 ms and dyssynchronous LV wall motion were classified into 2 groups based on the findings of (99m)Tc-methoxyisobutyl isonitrile (MIBI) quantitative gated single-photon emission computed tomography (SPECT) (QGS). Resynchronization was considered to be present when the difference between the QGS frame number for end-systole for the LV septal and lateral walls (dyssynchrony index) disappeared. Group A achieved resynchronization after BVP, but not Group B. In group A, New York Heart Association functional class (p=0.0002), specific activity scale (p=0.0001), total defect score (p<0.05), and the heart/mediastinum ratio of delayed (123)I-metaiodobenzylguanidine imaging (p<0.05) were significantly improved after resynchronization. However, there was no significant change in group B.
  
  
  CONCLUSIONS
  Cardiac resynchronization after BVP can improve cardiac symptoms, exercise capacity, and SNA in patients with moderate to severe CHF.
authors.affiliation: Department of Medicine and Biological Science, Graduate School of Medicine, Gunma University, Maebashi, Japan. kyonpy@m2.dion.ne.jp
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Higuchi
authors.forename: Takuji
authors.initials: T
authors.lastname: Toyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.forename: Shigeto
authors.initials: S
authors.lastname: Naito
authors.forename: Sigeru
authors.initials: S
authors.lastname: Ohshima
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kurabayashi
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000628:therapy; D002908:Chronic Disease; D005069:Evaluation Studies as Topic; D017079:Exercise Tolerance; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012720:Severity of Illness Index; D013564:Sympathetic Nervous System; D015899:Tomography, Emission-Computed, Single-Photon