Je. Burnes et al., Noninvasive ECG imaging of electrophysiologically abnormal substrates in infarcted hearts - A model study, CIRCULATION, 101(5), 2000, pp. 533-540
Citations number
16
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Background-Myocardial infarction and subsequent remodeling create substrate
s with altered electrophysiological (EP) properties that are highly arrhyth
mogenic. Existing ECG methods cannot always detect the existence of such su
bstrates nor provide any detailed information about their EP characteristic
s. A noninvasive method with such capabilities is greatly needed for identi
fying patients at risk of arrhythmias and for guidance and evaluation of th
erapy. Recently, we developed a noninvasive ECG imaging modality that can r
econstruct epicardial EP information from body surface potentials. We exten
ded its application to hearts with structural disease and examined its abil
ity to detect and characterize abnormal EP substrates.
Methods and Results-Epicardial potentials were recorded with a 490-electrod
e sock from an open-chest dog. Recordings were obtained from a normal heart
and from the same heart 2 hours after left anterior descending coronary ar
tery occlusion and ethanol injection to create an infarct. Body surface pot
entials were generated from these epicardial potentials in a human torso mo
del. Realistic geometry errors and measurement noise were added to the tors
o data, which were then used to noninvasively reconstruct epicardial potent
ials and electrograms (EGMs), with excellent accuracy. EP characteristics a
ssociated with the infarct substrate were reconstructed, including (1) a ne
gative region over the infarct, (2) EGMs with large predominant negative de
flections (eg, Q-wave EGMs), (3) Q-wave EGMs with superimposed RS deflectio
ns reflecting local activation of surviving myocardium within the infarct b
order zone, (4) reduced magnitudes of EGM negative derivatives, and (5) neg
ative QRS integrals of EGMs over the infarct.
Conclusions-ECG imaging can noninvasively detect and map abnormal EP substr
ates associated with infarction and structural heart disease.