Association between ventricular repolarization variables and cardiac diastolic function: A cross-sectional study of a healthy Chinese population

BACKGROUND: Diastolic electromechanical couple, a well-described phenomenon in symptomatic heart failure, has not been well studied in healthy people. We hypothesized that ventricular repolarization variables, such as the QT interval, Tpeak-to-Tend (Tpe) interval and Tpe/QT ratio, are associated with cardiac diastolic function in the healthy Chinese population. AIM: To assess the relationship between ventricular repolarization variables and cardiac diastolic function in apparently healthy Chinese individuals. METHODS: This was a community-based cross-sectional study conducted in Shenyang, China. A total of 414 healthy subjects aged 35-91 years were enrolled. All subjects underwent standard 12-lead electrocardiography (ECG) and comprehensive echocardiography. ECG enabled the measurement of QT and Tpe intervals and Tpe/QT ratio. echocardiographic parameters, such as the ratio of mitral early diastolic inflow velocity (E) and late diastolic inflow velocity (A), E-wave deceleration time, left atrial volume (LAV) and LAV index, were measured to assess diastolic function. E/A < 0.75 was considered to indicate reduced diastolic function. ECG and echocardiography results were analyzed separately and in a blinded fashion. Correlation and regression analyses were applied to determine associations. CONCLUSION: Repolarization variables are associated with cardiac diastolic function even in healthy people. Moderate levels of the QTc interval exert a protective effect on diastolic dysfunction in men.