(Ebook) Electrocardiographic assessment of repolarization heterogeneity by Bart Hooft van Huysduynen ISBN 9789090206165, 9090206167

(Ebook) Electrocardiographic assessment of repolarization heterogeneity by Bart Hooft van Huysduynen ISBN 9789090206165, 9090206167

the electrocardiographic assessment of repolarization heterogeneity. The term repolarization heterogeneity refers to differences in repolarization instants in the heart. Normally, repolarization in the human heart is a relatively smooth, continuous process, during which adjacent areas repolarize almost simultaneously. Several drugs or cardiac diseases may disturb the repolarization and thus increase the repolarization heterogeneity, which predisposes to arrhythmias. A non-invasive index able to assess this repolarization heterogeneity would have great clinical value. The standard 12-lead electrocardiogram (ECG) is attractive for this purpose as it is widely used and reflects repolarization heterogeneity: the morphology and duration of the T wave in the ECG depend on differences in the repolarization instants of the ventricular myocardial cells. The exact pattern of the normal repolarization in the human heart is still not precisely known. Several mapping and vectorcardiographic studies suggest that transmural (perpendicular to the myocardial wall) and paramural (along the ventricular walls) repolarization differences determine the normal morphology of the T-wave. Different electrocardiographic measures of T-wave morphology reflect different characteristics of cardiac repolarization, which defines their suitability to assess repolarization heterogeneity, as extensively discussed in this chapter