Medical & Biological Engineering & Computing

, Volume 52, Issue 4, pp 375–391 | Cite as

Evaluation of ventricular repolarization dispersion during acute myocardial ischemia: spatial and temporal ECG indices

  • Pedro David Arini
  • Fabricio Hugo Baglivo
  • Juan Pablo Martínez
  • Pablo Laguna
Original Article

Abstract

In this work, we studied the evolution of different electrocardiogram (ECG) indices of ventricular repolarization dispersion (VRD) during acute transmural myocardial ischemia in 95 patients undergoing percutaneous coronary intervention (PCI). We studied both temporal indices of VRD (T-VRD), based on the time intervals of the ECG wave, and spatial indices of VRD (S-VRD), based on the eigenvalues of the spatial correlation matrix of the ECG. The T-wave peak-to-end interval ITPE index showed statistically significant differences during left anterior descending artery and right coronary artery (RCA) occlusion for almost the complete time course of the PCI procedure with respect to the control recording. Regarding S-VRD indices, we observed statistically significant increases in the ratio of second to the first eigenvalue IT21, the ratio of the third to the first eigenvalue IT31 and the T-wave residuum ITWR during RCA occlusions. We also found a statistically significant increase in the IT31 during left circumflex artery occlusions. To evaluate the evolution of VRD indices during acute ischemia, we calculated the relative change parameter RI for each index I. Maximal relative changes (RI) during acute ischemia were found for the S-VRD indices IT21, the first eigenvalue Iλ1 and the second eigenvalue Iλ2, with changes 64, 57 and 52 times their baseline range of variation during the control recording, respectively. Also, we found that relative changes with respect to the baseline were higher in patients with T-wave alternans (TWA) than in those without TWA. In conclusion, results suggest that ITPE as well as IT21, IT31 and ITWR are very responsive to dispersion changes induced by ischemia, but with a behavior which very much depends on the occluded artery.

Keywords

Ischemia Repolarization dispersion PCA 

Abbreviations

2D

Two dimensional

3D

Three dimensional

AMI

Acute myocardial infarction

APD

Action potential duration

CAD

Coronary artery disease

CGM

Cardiogoniometry

ECG

Electrocardiogram

LAD

Left anterior descending artery

LCx

Left circumflex artery

LM

Left main artery

MAP

Monophasic action potential

MI

Myocardial infarction

PCA

Principal component analysis

PCI

Percutaneous coronary intervention

RCA

Right coronary artery

SCD

Sudden cardiac death

SEM

Standard error mean

SPECT

Single-photon emission computed tomography

STAFF-III

Database of the ECG signals

STEMI

ST-segment elevation myocardial infarction

SVD

Singular value decomposition

S-VRD

Spatial indices of ventricular repolarization dispersion

TP

Total population

T-VRD

Temporal indices of ventricular repolarization dispersion

TWA

T-wave alternans

VCG

Vectorcardiogram

VRD

Ventricular repolarization dispersion

σI

Standard deviation of I index at control recording

I

Index

Iλ1

First eigenvalue

Iλ2

Second eigenvalue

Iλ3

Third eigenvalue

IT21

Ratio of the second to the first eigenvalues

IT31

Ratio of the third to the first eigenvalues

IMTW

Multilead T-wave width

ITE

Total energy of the T-wave

ITPE

T-wave peak-to-end in the lead with maximal level of ST-segment

ITW

T-wave width in the lead with maximal level of ST-segment

ITWR

T-wave residuum

RI

Relative variation of the index I

\(\hbox{ST}_{\rm J+60}\)

ST level measured at J-point plus 60 ms

TEND

T-wave end

TON

T-wave onset

TPEAK

T-wave peak

Notes

Acknowledgments

This work was supported by the Ministerio de Ciencia e Innovación, Spain, under Projects TEC2010-21703-C03-02, by the Diputación General de Aragón, Spain, through Grupos Consolidados GTC and Fondo Social Europeo ref: T30, by Instituto de Salud Carlos III, Spain, through CIBER CB06/01/0062. This work was also funded by the Consejo Nacional de Investigaciones Científicas y Técnicas (PIP-538) and Agencia Nacional de Promoción Científica y Tecnológica (PICT 2008 nro. 2108), Argentina.

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Copyright information

© International Federation for Medical and Biological Engineering 2014

Authors and Affiliations

  • Pedro David Arini
    • 1
    • 2
  • Fabricio Hugo Baglivo
    • 3
  • Juan Pablo Martínez
    • 4
    • 5
  • Pablo Laguna
    • 4
    • 5
  1. 1.Argentine Institute of Mathematics‘Alberto P. Calderón’ (CONICET)Buenos AiresArgentina
  2. 2.Biomedical Engineering Institute, School of EngineeringUniversity of Buenos Aires (UBA)Buenos AiresArgentina
  3. 3.Electronic Engineering Department, School of EngineeringUniversity of Buenos Aires (UBA)Buenos AiresArgentina
  4. 4.Communications Technology Group (GTC), Aragón Institute of Engineering Research (I3A), IIS AragónUniversity of ZaragozaZaragozaSpain
  5. 5.Biomedical Research Networking Center in BioengineeringBiomaterials and Nanomedicine (CIBER-BBN)ZaragozaSpain

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