Effects of Valsartan Therapy on QT Interval Dispersion in Congestive Heart Failure
Aim: The aim of the research was to investigate the effects of Valsartan therapy on QT interval dispersion (QTd) in patients with Chronic Heart Failure (CHF). Material and Method: A sample of ambulatory patients, aged 22-79 years in NYHA class II to IV, with ventricular ejection fraction < 45 %, were followed prospectively. The patients were evaluated for hypertension, diabetes mellitus, smoking, alcohol abuse, concomitant medications, and QTd. Valsartan therapy was initiated in a dose of 80 mg once a day. Six months later, the patient were re-evaluated. Twelve lead electrocardiogram was recorded prior to and after 6 months Valsartan therapy. Data were analyzed according to the distribution at a significance level of 5% by using Statistica 6.0 software. Results: Eighty ambulatory patients were included in the study and they were divided into: group I, aged ≤ 65 years (n= 44), and group II, aged > 65 years (n = 36). At 6 months, there were identified on both groups that QTd significantly decreased comparing with baseline values (85 ms vs 112 ms; Wilcoxon Z = 7.77, n = 80, p < 0.001). Conclusions: The results of the study showed that, in ambulatory patients with CHF, 6 months Valsartan therapy significantly decreases QTd. The decrease of the QTd was uniformly distributed between patients aged ≤ 65 years and those aged > 65 years. The reduction in QTd in patients with CHF using Valsartan could be responsible by the reduction in the risk of sudden cardiac death in the investigated group.