title: Cardiac time intervals and the association with 2D-speckle-tracking, tissue Doppler and conventional echocardiography: the Thousand&1 Study.
abstract: Cardiac time intervals (CTI) are prognostic above and beyond conventional echocardiographic measures. The explanation may be that CTI contain information about both systolic and diastolic measures; this is, however, unknown. The relationship between the CTI and systolic and diastolic function assessed by conventional, tissue Doppler (TDI) and speckle-tracking echocardiography (STE) was investigated. CTI and echocardiographic measurements, including conventional, STE, and TDI echocardiography, were studied in 1088 type 1 diabetes patients without known heart disease randomly selected from the out-patient clinic at Steno Diabetes Center. The CTI were obtained by TDI M-mode through the mitral leaflet and included the isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), and the myocardial performance index (MPI = (IVRT + IVCT)/ejection time). Standardized beta-values were assessed. Both systolic and diastolic measures associated with CTI. Conventional measures: left ventricular ejection fraction (stand. beta): MPI -0.34, IVRT 0.24, and IVCT -0.21, all p < 0.001. For the TDI measures, the most significant association was found with e': MPI (stand. beta: -0.30, p < 0.001) and IVRT (-0.35, p < 0.001) but no association with IVCT -0.05, p = 0.1). Speckle-tracking derived measures were in general strongly associated with the cardiac time intervals. Thus, global longitudinal strain and MPI (-0.38, p < 0.001), IVRT (-0.23, p < 0.001), and IVCT (-0.10, p < 0.001); and global longitudinal strain rate e and MPI (-0.40, p < 0.001), IVRT (-0.42, p < 0.001), and IVCT (-0.04, p = 0.11). CTI, in particular MPI and IVRT, associate with both systolic and diastolic myocardial function assessed by conventional and newer echocardiographic measures. This may possibly help to explain the prognostic significance of CTI.
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdsvej 28, 2900, Hellerup, Denmark.
authors.forename: Tor
authors.initials: T
authors.lastname: Biering-Sørensen
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdsvej 28, 2900, Hellerup, Denmark.|Institute of Clinical Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark.
authors.forename: Jan Skov
authors.initials: JS
authors.lastname: Jensen
authors.affiliation: Steno Diabetes Center, Niels Steensens Vej 2, 2820, Gentofte, Denmark.
authors.forename: Henrik Ullits
authors.initials: HU
authors.lastname: Andersen
authors.affiliation: Steno Diabetes Center, Niels Steensens Vej 2, 2820, Gentofte, Denmark.|Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark.|Faculty of Health, University of Aarhus, Katrinebjergvej 89F, 8200, Aarhus N, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Rossing
authors.affiliation: Department of Internal Medicine, Holbaek Hospital, Smedelundsgade 60, 4300, Holbæk, Denmark. magnustjensen@gmail.com.|Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdsvej 28, 2900, Hellerup, Denmark. magnustjensen@gmail.com.|Steno Diabetes Center, Niels Steensens Vej 2, 2820, Gentofte, Denmark. magnustjensen@gmail.com.
authors.forename: Magnus Thorsten
authors.initials: MT
authors.lastname: Jensen
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003718:Denmark; D003971:Diastole; D018618:Echocardiography, Doppler, Color; D018619:Echocardiography, Doppler, Pulsed; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D013318:Stroke Volume; D013599:Systole; D013997:Time Factors; D016277:Ventricular Function, Left
keywords: Cardiac time intervals; Echocardiography; Speckle-tracking; Tissue Doppler imaging