Significance of QTc Prolongation on Ventricular Arrhythmias in Patients with Left Ventricular Hypertrophy Secondary to Essential Hypertension

The present study was designed to detect the arrhythrnogenic effect of left ventricular hypertrophy (L VH), QTc duration, and the relationship between the QT duration and ventricular arrhythmias in patients w ith L VH secondary to essential hypertension (EH). We studied 68 hypertensive patients with L VH (28 men and 10 women, mean age 52±5 years) and without LVH (23 men and 7 women, mean age 51±6 years). Thirty healthy normotensive subjects (22 men and 8 women, mean age 49±6 years) were selected to serve as the control group. We investigated the frequency of ventricular arrhythmias by means of 24-hours ambulatory electrocardiographic monitoring; and grade 3 and 4 arrhythmias according to modified Lown and Wolf classification were accepted as complex arrhythmias. The QT interval was measured from the beginning of the QRS complex to the end of the T wave in lead II. Using Bazett formula, QT interval was corrected (QTc) for heart rate. Complex ventricular arrhythmias were observed more in hypertensive patients with LVH than in hypertensive patients without L VH and in normotensive subjects (p<0.05). Also, a positive correlation was found between QTc duration and left ventricle mass (r=0.58, p