Therapeutic Research

Abstract

Background：QT dispersion is considered as a predictor of prognosis in patients with heart failure. Renin−angiotensin system is one of worsening factors to heart failure. Hypothesis：We designed a prospective study to determine whether combination therapy of an ACE inhibitor and an angiotensin I I receptor blocker, valsartan, more improves QT dispersion in patients with chronic heart failure（CHF）. Method：A tissue−selective ACE inhibitor（quinapril or trandolapril）or valsartan was administered to 26 patients with CHF for 3 months in a single−blind manner, and then to the ACE inhibitor group（n＝14）valsartan was concomitantly administered and to the valsartan group（n＝12）an ACE inhibitor was concomitantly administered. We performed echocardiography, Holter ECG, and measurements of endocrine hormones for both groups and compared the results. Results：A tissue−selective ACE inhibitor and valsartan significantly reduced QT dispersion by 41％ and 58％, respectively. Additive administration of valsartan to an ACE inhibitor significantly improved QT dispersion by 28％, whereas additive effect of an ACE inhibitor to valsartan exhibited no further improvement. Similar results were observed in Lown’s classification. Conclusion：The results demonstrated that adding valsartan to an ACE inhibitor was beneficial to improving QT dispersion and ventricular arrhythmia, whereas adding an ACE inhibitor to valsartan did not show any additive clinical benefit.