QT Dispersion & Left Ventricular Hypertrophy in Essential Hypertensive Patients
Abstract
Background: Left ventricular hypertrophy (LVH) is an important indicator of target organ damage in chronic arterial hypertension. An increased risk for life-threatening arrhythmias and sudden death have been observed in hypertensive patients, associated with either left ventricular hypertrophy (LVH) or prolonged QT interval. Present study was conducted to compare QT dispersion in hypertensive patients with LVH & without LVH.
Methods: Forty male subjects affected by essential hypertension with & without LVH, underwent 12 lead ECG recording for QT dispersion and 2D echocardiography performed to measure interventricular septal thickness, posterior wall thickness and left ventricular internal diameter & compared with normal age & sex matched control.
Results: There was statistically significant increase in QT dispersion (p<0.05) in hypertensive subjects with LVH as compared to non-LVH group. Multivariate analysis demonstrated significant relationship between QT dispersion and systolic, diastolic & mean blood pressure, Left ventricular mass & Left ventricular mass index.
Conclusion: Sympatho-vagal imbalance in hypertensive patients with LVH could contribute to abnormal ventricular repolarization process leading to prolongation of QT dispersion. Manual measurement of QT dispersion might be a simple, non-invasive screening procedure to identify the hypertensive at greatest risk of sudden cardiac death.
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References
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