[Prognostic value of duration and variability of QT and RR intervals in general population of Novosibirsk].

Increased duration and dispersion of QT interval and lowered variability of RR interval are considered to be probable precursors of dangerous ventricular arrhythmias and sudden death. Standard epidemiological methods were used for the study of a representative sample of nonorganized male population (age 25-64 years) in Novosibirsk in a framework of the MONICA project. Database of the total mortality register was used for verification of deaths. Resting ECGs were analyzed using the Minnesota code criteria blindly relative to other data of the study. Duration and dispersion of QT and QTc intervals as well as temporal parameters of RR variability were determined manually. Assessment of significance of these factors for prognosis was made with the use of methods of survival analysis. Among all characteristics of QTc interval maximal duration and dispersion of QTc were the strongest predictors of death from any cause and cardiovascular death being independent of age, mean blood pressure, ischemic heart disease, body mass index and smoking. Predictive power of these QTc interval parameters was similar in total male population and in subpopulation of patients with cardiovascular diseases. In men without cardiovascular diseases parameters of RR variability on ECG at rest were predictors of cardiovascular death independent of age, mean blood pressure, body mass index, total cholesterol and smoking.