title: Comparison of the prognostic value of cardiac iodine-123 metaiodobenzylguanidine imaging and heart rate variability in patients with chronic heart failure: a prospective study.
abstract: OBJECTIVE
  We sought to prospectively compare the prognostic value of cardiac iodine-123 (I-123) metaiodobenzylguanidine (MIBG) imaging with that of heart rate variability (HRV) in patients with mild-to-moderate chronic heart failure (HF).
  
  
  BACKGROUND
  Cardiac I-123 MIBG imaging, which reflects cardiac adrenergic nerve activity, provides prognostic information on chronic HF patients. Reduced HRV, indicating derangement in cardiac autonomic control, was also reported to be associated with a poor prognosis in chronic HF patients.
  
  
  METHODS
  At study entry, I-123 MIBG imaging and 24-h Holter monitoring were performed in 65 chronic HF outpatients with a radionuclide left ventricular ejection fraction <40%. The cardiac MIBG heart to mediastinum ratio (H/M) and washout rate (WR) were obtained from MIBG imaging. The time and frequency domain parameters of HRV were calculated from 24-h Holter recordings.
  
  
  RESULTS
  At a mean follow-up of 34 +/- 19 months, WR (p < 0.0001), H/M on the delayed image (p = 0.01), and normalized very-low-frequency power (n-VLFP) (p = 0.047) showed a significant association with the cardiac events (sudden death in 3 and hospitalization for worsening chronic HF in 10 patients) on univariate analysis. Multivariate analysis revealed that WR was the only independent predictor of cardiac events, although the predictive accuracy for the combination of abnormal WR and n-VLFP significantly increased, compared with that for abnormal WR (82% vs. 66%, p < 0.05).
  
  
  CONCLUSIONS
  Cardiac MIBG WR has a higher prognostic value than HRV parameters in patients with chronic HF. The combination of abnormal WR and n-VLFP would be useful to identify chronic HF patients at a higher risk of cardiac events.
authors.affiliation: Division of Cardiology, Osaka Prefectural General Hospital, Japan. tyamada@gh.pref.osaka.jp
authors.forename: Takahisa
authors.initials: T
authors.lastname: Yamada
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Shimonagata
authors.forename: Masatake
authors.initials: M
authors.lastname: Fukunami
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Kumagai
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Ogita
authors.forename: Akio
authors.initials: A
authors.lastname: Hirata
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Asai
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Makino
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Kioka
authors.forename: Hideo
authors.initials: H
authors.lastname: Kusuoka
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Hori
authors.forename: Noritake
authors.initials: N
authors.lastname: Hoki
mesh_terms: D019797:3-Iodobenzylguanidine; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine