Document Detail


Is septal glucose metabolism altered in patients with left bundle branch block and ischemic cardiomyopathy?
MedLine Citation:
PMID:  17079808     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Left bundle branch block (LBBB) is common in patients with heart failure (HF) and contributes to left ventricular (LV) dysfunction. The abnormal septal motion may alter septal metabolic demand but this has not been well characterized in patients with ischemic cardiomyopathy (ICM) and LV dysfunction. The aim of this study was to determine the effect of LBBB on septal metabolism in patients with ICM, LV dysfunction, and LBBB. METHODS: Fifty-three patients with LV dysfunction and ICM were identified: 34 with LBBB, 19 with normal QRS (</=100, control patients). PET using (18)F-FDG and (82)Rb was used to measure myocardial glucose metabolism and perfusion, respectively. Perfusion-metabolism differences were determined. Scar scores (matched decreases in (18)F-FDG and (82)Rb), mismatch scores (hibernating myocardium with decreased (82)Rb relative to (18)F-FDG), and reverse-mismatch (R-MM) scores (reduced (18)F-FDG relative to (82)Rb) were assessed in the septum and lateral wall. RESULTS: (18)F-FDG uptake in the septum was reduced in patients with LBBB (64.0% +/- 15.4%) compared with control patients (74.9% +/- 14.3%; P < 0.05). Mean septal R-MM was greater in patients with LBBB (19.1% +/- 15.3%) versus control patients (4.7% +/- 10.6%; P < 0.05). However, 32% (11/34) of patients with LBBB did not demonstrate septal R-MM, 91% (10/11) of whom demonstrated lateral wall perfusion defects. Of the 68% (23/34) of patients with LBBB and septal R-MM, 52% (12/23) demonstrated lateral wall perfusion defects (P < 0.05). There was a significant difference in the percentage of the lateral wall with scar between those with septal R-MM (9.3% +/- 10.5%) and those without (19.9% +/- 14.3%; P < 0.05). CONCLUSION: Previously, LBBB was believed to be characterized by reduced glucose metabolism relative to perfusion in the septum; however, this is not always the case in ICM. LBBB is not associated with septal R-MM in >30% of this patient population. Absence of this finding was often associated with lateral wall perfusion defects, suggesting an alteration in the metabolic demand on the septum. This may have implications for HF therapies such as resynchronization and requires further study.
Authors:
Kerry Thompson; George Saab; David Birnie; Benjamin J W Chow; Heikki Ukkonen; Karthik Ananthasubramaniam; Robert A Dekemp; Linda Garrard; Terrence D Ruddy; Jean N Dasilva; Rob S B Beanlands
Related Documents :
1499178 - Histologic evidence of myocardial damage in apparently healthy subjects with ventricula...
18769308 - Early detection of right ventricular functional abnormalities in patients with complex ...
17116268 - Echocardiographic analysis of the subtypes of right ventricular restrictive physiology ...
3258468 - A comparative study of thallium-201 single-photon emission computed tomography and elec...
17611248 - Pneumonitis associated with sirolimus: clinical characteristics, risk factors and outco...
7884838 - Cue-elicited cocaine craving and autogenic relaxation. association with treatment outcome.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of nuclear medicine : official publication, Society of Nuclear Medicine     Volume:  47     ISSN:  0161-5505     ISO Abbreviation:  J. Nucl. Med.     Publication Date:  2006 Nov 
Date Detail:
Created Date:  2006-11-02     Completed Date:  2006-12-26     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0217410     Medline TA:  J Nucl Med     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1763-8     Citation Subset:  IM    
Affiliation:
Division of Cardiology, National Cardiac PET Centre, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Bundle-Branch Block
Cardiomyopathies / pathology*
Electrocardiography / methods
Female
Glucose / metabolism*
Heart Septum / metabolism*
Humans
Image Processing, Computer-Assisted
Male
Middle Aged
Myocardial Ischemia / pathology
Myocardium / pathology
Perfusion
Positron-Emission Tomography / methods*
Chemical
Reg. No./Substance:
50-99-7/Glucose

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The prevalence of myocardial ischemia after concurrent chemoradiation therapy as detected by gated m...
Next Document:  PET measurement of cardiac and nigrostriatal denervation in Parkinsonian syndromes.