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Value of the frontal planar QRS-T angle on cardiac dysfunction in patients with old myocardial infarction
Yan-Hong Li1, Xue-Jun Ren, Zhi-Hong Han
1Department of Cardiology, Institute of Heart Lung and Blood Vessel Disease, Beijing Anzhen Hospital Affiliated to Capital Medical University Beijing 100029, China.
Objectives:
To explore a method of surface electrocardiogram for assessing cardiac dysfunction in patients with old myocardial infarction.
Methods:
1000 patients with old myocardial infarction in Anzhen hospital were analyzed retrospectively. The planar QRS-T angle was calculated automatically according to QRS-wave and T-wave vectors by the electrocardiogram machine.
Results:
Among these 1000 patients, 822 (82.2%) were male and 178 (17.8%) were female, the mean age was 59.3±10.5 years (34~89 years). The average planar QRS-T angle was 88.5±50.6°. The planar QRS-T angle and LVEF was negative correlation (r=-0.406, p<0.01), the lower the LVEF, the better the relationship with planar QRS-T angle. QRS-T angle>90° had optimal sensitivity and specificity (76%, 74%) in diagnosis of cardiac dysfunction.
Conclusion:
The planar QRS-T angle and LVEF of patients with old myocardial infarction is negative correlation, the larger the planar QRS-T angle, the lower the LVEF. The planar QRS-T angle may be an easier and more feasible index for assessing cardiac dysfunction in patients with old myocardial infarction.
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