Abstract

AIM: Increased QT dispersion is associated with sudden cardiac deathin congestive heart failure, hypertrophic cardiomyopathy, and following acute myocardial infarction. Patients with hypertension, in particular those with left ventricular hypertrophy, are also at greater risk of sudden cardiac death. We examined the incidence of QT dispersion in essential hypertensive group and its correlation with left venticular hypertrophy. METHODS: In this study, 48 hypertensive patients were evaluated, 24 of them had left ventricular hypertrophy and the remainder did not. As a control group 30 normal patients were examined. All the 78 subjects had a routine surface 12-lead electrocardiogram, QT dispersion measured from that, and two-dimensional echocardiography performed to determine left ventricular hypertrophy in the statistical evaluation of the study, subjects were grouped as hypertensives and normotensives, Hypertensives were classified two subgroups whether they had left ventricular hypertrophy or not. RESULTS: In our study, hypertensive patients had significantly increased QT dispersion values compared to normotensive control group (p<0.01), Hypertensive patients, those with left ventricular hypertrophy had significantıy higher values than those without hypertrophy (p<0.05) and vecy high values compared to normotensive group (p<0.01). On the other hand, hypertensive patients who did not have left ventricular hypertrophy, also had higher values than normotensives. In the hypertensive patient group significant corelation was found between QT dispersion and left ventricle mass index (p>0.01). Similar findings were obtained when QT dispersion value was also corrected for heart rate (QTc dispersion). CONCLUSION: In this study, increased QT dispersion is found in those essential hypertensives compared to normotensives. Hypertensive patients that have left ventricle hypertrophy are more susceptible to increased QT dispersion. Patients with elevated blood pressure without left ventricle hypertrophy are also prone to increased QT dispersion. Since this relationship persist even in the absence of left ventricular hypertrophy, measurement of QT dispersion, might be a simple, noninsavive screening prmedure of indentify those hypertensives at greatest risk of sudden death.