Abstract 13995: The Cardiac Time Intervals Measured by Tissue Doppler Imaging M-mode: The Association with Hypertension, Left Ventricular Geometry and the Usefulness in Predicting Hypertension Related Diseases
Purpose: To test the hypothesis that the cardiac time intervals reveals reduced myocardial function in persons with hypertension and are strong predictors of future hypertension related diseases in the general population.
Methods: In a large community based population study, cardiac function was evaluated in 1,915 participants by both conventional echocardiography and by tissue Doppler imaging (TDI). The cardiac time intervals, including the isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), and the ejection time (ET) were obtained by TDI M-mode through the mitral leaflet. IVCT/ET, IVRT/ET and the myocardial performance index (MPI=(IVRT+IVCT)/ET) were calculated.
Results: After multivariable adjustment for clinical variables and conventional echocardiography the IVRT, IVRT/ET and MPI, remained significantly impaired in persons with hypertension (n=826) compared to participants without (n=1082). Additionally, they displayed a significant dose-response relationship, between increasing severity of elevated blood pressure and increasing left ventricular mass index. Furthermore, during follow-up of median 10.7 years 435 had a cardiovascular event (CVD), defined as stroke, ischemic heart disease and/or peripheral artery disease. The IVRT/ET and MPI were powerful and independent predictors of future CVD (See Figure) especially in participants with known hypertension. They provide prognostic information over and above clinical variables from the Framingham Risk Score, the SCORE risk chart and the ESH/ESC risk chart.
Conclusion: The cardiac time intervals identify impaired cardiac function in individuals with hypertension, not only independent of conventional risk factors and echocardiographic parameters, but also in participants with a normal conventional echocardiographic examination. The IVRT/ET and MPI are independent predictors of future CVD especially in participants with known hypertension.
Author Disclosures: T. Biering-Sørensen: None. R. Mogelvang: None. P. Schnohr: None. J. Jensen: None.
- © 2014 by American Heart Association, Inc.