PMID- 19626384
OWN - NLM
STAT- MEDLINE
DCOM- 20100202
LR  - 20240130
IS  - 1532-6551 (Electronic)
IS  - 1071-3581 (Linking)
VI  - 16
IP  - 6
DP  - 2009 Nov-Dec
TI  - Optimization and validation of radionuclide angiography phase analysis parameters 
      for quantification of mechanical dyssynchrony.
PG  - 895-903
LID - 10.1007/s12350-009-9119-4 [doi]
AB  - INTRODUCTION: Cardiac resynchronization therapy (CRT) has the potential to 
      improve the outcome of patients suffering from mechanical dyssynchrony and heart 
      failure. It has been suggested that accurate quantification of baseline extent of 
      mechanical dyssynchrony may lead to pre-selection of patients likely to respond 
      to CRT. The standard deviation from a phase histogram (phaseSD), synchrony (S) 
      and entropy (E) are parameters obtained from phase analysis of planar 
      radionuclide angiography (RNA) that may provide an accurate means of assessing 
      mechanical dyssynchrony. In this paper, the ability of phaseSD, S, and E to 
      detect mechanical dyssynchrony was investigated and optimal values for image 
      smoothing, histogram noise thresholding, and bin size were defined. Finally, the 
      intra- and inter-observer reproducibility of the methodology was assessed. 
      METHODS: PhaseSD, S, and E were calculated for 37 normal subjects (LVEF > 50%, 
      end-diastolic volume < 120 mL, end-systolic volume < 60 mL, QRS < 120 ms, and 
      normal wall motion) and 53 patients with mechanical dyssynchrony (LVEF < 30%, QRS 
      > 120 ms, and typical LBBB). Receiver-operator characteristics (ROC) curves were 
      created and the area under the curve (AUC), for each parameter, was determined 
      using three different imaging filters (no filter and an order 5 Hann filter with 
      cut-off of 5/50 and 10/50). The AUC was also determined using histogram threshold 
      values varying between 0% and 50% (of the max amplitude value). Finally, AUC for 
      E was determined for bins sizes varying between 1 degrees and 20 degrees . Inter- 
      and intra-observer variability was calculated at optimal imaging values. RESULTS: 
      No smoothing was found to maximize the AUC. The AUC was independent of histogram 
      threshold value. However, a value of 20% provided optimal visualization of the 
      phase image. The AUC was also independent of bin size. At the optimal imaging 
      values, the sensitivity and specificity for all parameters for detection of 
      mechanical dyssynchrony was measured to be 89-100%. Inter- and intra-observer 
      correlation coefficients >0.99 were found for phaseSD, S and E. CONCLUSIONS: 
      Optimized planar RNA phase analysis parameters, phaseSD, S, and E, were able to 
      detect mechanical dyssynchrony with low inter- and intra-observer variability. 
      Studies assessing the ability of these parameters to predict CRT outcome are 
      required.
FAU - Wassenaar, Richard
AU  - Wassenaar R
AD  - Division of Nuclear Medicine, The Ottawa Hospital, Ottawa, ON, K1Y 4E9, Canada. 
      rwassenaar@ottawahospital.on.ca
FAU - O'Connor, David
AU  - O'Connor D
FAU - Dej, Barbora
AU  - Dej B
FAU - Ruddy, Terrence David
AU  - Ruddy TD
FAU - Birnie, David
AU  - Birnie D
LA  - eng
PT  - Evaluation Study
PT  - Journal Article
PT  - Validation Study
DEP - 20090722
PL  - United States
TA  - J Nucl Cardiol
JT  - Journal of nuclear cardiology : official publication of the American Society of 
      Nuclear Cardiology
JID - 9423534
SB  - IM
CIN - J Nucl Cardiol. 2009 Nov-Dec;16(6):846-8. PMID: 19798545
MH  - Aged
MH  - *Algorithms
MH  - Female
MH  - Humans
MH  - Image Enhancement/*methods
MH  - Image Interpretation, Computer-Assisted/*methods
MH  - Male
MH  - Middle Aged
MH  - Myocardial Perfusion Imaging/*methods
MH  - Reproducibility of Results
MH  - Sensitivity and Specificity
MH  - Tomography, Emission-Computed, Single-Photon/*methods
MH  - Ventricular Dysfunction, Left/*diagnostic imaging
EDAT- 2009/07/25 09:00
MHDA- 2010/02/03 06:00
CRDT- 2009/07/24 09:00
PHST- 2009/02/05 00:00 [received]
PHST- 2009/06/30 00:00 [accepted]
PHST- 2009/06/18 00:00 [revised]
PHST- 2009/07/24 09:00 [entrez]
PHST- 2009/07/25 09:00 [pubmed]
PHST- 2010/02/03 06:00 [medline]
AID - S1071-3581(23)03518-3 [pii]
AID - 10.1007/s12350-009-9119-4 [doi]
PST - ppublish
SO  - J Nucl Cardiol. 2009 Nov-Dec;16(6):895-903. doi: 10.1007/s12350-009-9119-4. Epub 
      2009 Jul 22.