NEW CORRELATION BETWEEN ANGLES OF WIDE QRS COMPLEX IN ELECTROCARDIOGRAM AND ECHOCARDIOGRAPHIC INDICES

Background: heart failure (hf) due to left ventricular (lv) systolic dysfunction has less ersurvival than diastolic hf .we examined the correlation of two new angles(ß and α ) of qrscomplex in the electrocardiogram (ecg) with indices including left ventricular ejection fraction(lvef),left ventricular end systolic dimension (lvesd) and left ventricular end diastolic dimension(lvedd) for predicting lvef.methods: in this cross.sectional study,159 subjects with clinical signs of lv systolic dysfunctionwho presented to the al-zahra hospital in isfahan, iran , underwent echocardiography.first ,on the ecg ,two new angles defined and then these two angles compared manually andwith computerized analysis by two different observers blinded to the another data. after confirmationof excellent correlation between these two forms, then two angles measured manually with protractor in 159 patients (wide qrs complex in 59 and normal in 100 patients). then, correlationbetween these angles and echocardiographic indices were assessed.results: statistical analysis revealed that in normal qrs complex, there was no correlationbetween any of two angles and echocardiographic indices. in contrast, in wide qrs complex,ƒàangle and ß/α ratio was correlated with any three echocardiographic indices (negative correlationwith lvef and positive correlation with lvesd and lvedd) i.e. with decrease in lvefand increase in lvesd and lvedd, ß angle is widened and ß/αratio increases.a lvef of 30% corresponded to ß ratio of 2 in wide qrs complex patients on the regressionline. linear regression analysis generated the regression line equation for predicting the lvef.the equation is lvef = 60.6 . (14.5 *ß/α ratio).