Document Detail


Body surface projection of action potential duration alternans: a combined clinical-modeling study with implications for improving T-wave alternans detection.
MedLine Citation:
PMID:  19632636     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: Action potential duration alternans (APDA) can vary regionally in magnitude and phase. The influence of APDA heterogeneity on T-wave alternans (TWA) has not been defined. OBJECTIVE: Our objectives were: (1) to determine how APDA affects the magnitude and spatial distribution of TWA, and (2) to optimize electrocardiographic (ECG) lead configuration accordingly to improve TWA detection. METHODS: Global, regional, and discordant APDA were simulated in a 257-node heart model. Using a forward solution, body surface potentials were derived at 300 points on the thorax and TWA was computed at each point. In 22 patients with cardiomyopathy (left ventricular ejection fraction 28% +/- 6%), TWA was measured from a 114-electrode body surface map using the spectral method during atrial pacing at 110 beats/min. RESULTS: An increase in global APDA from 4 to 12 ms resulted in an increase in maximum TWA from 10 to 30 microV. TWA magnitude varied with the size and location of the alternating myocardium, but was largest with discordant APDA compared with regional or global APDA. Irrespective of the location or phase of APDA, TWA was largest over the precordium and correlated with T-wave amplitude in the simulation (R(2) = 0.56 +/- 0.24, P <.01) and clinical study (R(2) = 0.45 +/- 0.23, P <.02). A novel lead configuration (12 precordial leads + limb leads) significantly improved maximum TWA detection compared with the conventional 12-lead ECG+ Frank lead configuration. CONCLUSION: TWA magnitude is dependent on the interaction of concordant and discordant alternating sources within the heart. Maximum TWA consistently localizes to the precordium and a novel lead configuration using 12 precordial leads improves TWA quantification.
Authors:
Raja J Selvaraj; Adrian M Suszko; Anandaraja Subramanian; Dhinesh Sivananthan; Ann Hill; Kumaraswamy Nanthakumar; Vijay S Chauhan
Related Documents :
21599156 - Percolation-induced conductor-insulator transition in a system of metal spheres in a di...
22462836 - A second-order perturbation theory route to vibrational averages and transition propert...
14582606 - Impulsive-motion model for computing the closing motion of mechanical heart-valve leafl...
21981496 - New limit on time-reversal violation in beta decay.
3349066 - Effect of differences in optical properties of intermediate oxygenated species of hemog...
11088176 - Computer simulation evidence of the transient planar state during the homeotropic to fo...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; Validation Studies     Date:  2009-04-05
Journal Detail:
Title:  Heart rhythm : the official journal of the Heart Rhythm Society     Volume:  6     ISSN:  1556-3871     ISO Abbreviation:  Heart Rhythm     Publication Date:  2009 Aug 
Date Detail:
Created Date:  2009-07-27     Completed Date:  2009-11-06     Revised Date:  2009-12-07    
Medline Journal Info:
Nlm Unique ID:  101200317     Medline TA:  Heart Rhythm     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1211-9     Citation Subset:  IM    
Affiliation:
Division of Cardiology, University Health Network, Toronto, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Action Potentials*
Body Surface Potential Mapping*
Cardiomyopathies / diagnosis,  physiopathology*
Electrocardiography
Endocardium
Heart Conduction System / physiopathology*
Humans
Models, Biological
Pericardium
Statistics as Topic
Stroke Volume*
Time Factors
Ventricular Function, Left*
Comments/Corrections
Comment In:
Heart Rhythm. 2009 Dec;6(12):e1; author reply e1-2   [PMID:  19959112 ]
Heart Rhythm. 2009 Aug;6(8):1220-1   [PMID:  19632637 ]

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


Previous Document:  Predictive value of electrocardiographic QT interval and T-wave morphology parameters for all-cause ...
Next Document:  Paroxysmal atrioventricular block.