AUTHOR=Skampardoni Sofia , Green Darren , Hnatkova Katerina , Malik Marek , Kalra Philip A. , Poulikakos Dimitrios 

TITLE=QRS-T Angle Predicts Cardiac Risk and Correlates With Global Longitudinal Strain in Prevalent Hemodialysis Patients

JOURNAL=Frontiers in Physiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2019.00145

DOI=10.3389/fphys.2019.00145

ISSN=1664-042X

ABSTRACT=<p><bold>Background:</bold> Cardiovascular disease is the commonest cause of death in hemodialysis (HD) patients but accurate risk prediction is lacking. The spatial QRS – T angle is a promising electrophysiological marker for sudden cardiac death risk stratification. The aim of this study was to assess the prognostic value of spatial QRS-T angle derived from standard 12 lead electrocardiograms (ECG) and its association with echocardiographic parameters in HD patients.</p><p><bold>Methods:</bold> This prospective study of 178 prevalent HD patients (aged 67 ± 14 years, 72% men) collected ECG and echocardiographic data on an annual basis. Baseline echocardiograms at study entry were used for cross-sectional comparisons with ECGs. Study endpoints were all-cause mortality, cardiovascular mortality, and major adverse cardiac events (MACE). The QRS – T angle was calculated from standard 10-s ECG as the total cosine R to T (TCRT) using singular value decomposition and expressed in degrees. TCRT above 100° was defined as abnormal.</p><p><bold>Results:</bold> During a follow-up period of 36 ± 19 months, 74 patients died, including 17 cardiac deaths, and 54 suffered from MACE. In multivariate Cox regression analysis, QRS-T angle by TCRT at baseline was associated with increased cardiovascular mortality both as a continuous value and dichotomized below or above 100° (HR 1.016, <italic>p</italic> = 0.029, CI: 1.002–1.030 and HR 3.506, CI: 1.118–10.995, <italic>p</italic> = 0.031 respectively) and with MACE dichotomized at 100° (HR 1.902, CI: 1.046–3.459; <italic>p</italic> = 0.035). In multivariate regression analysis including baseline parameters, echocardiographic global longitudinal strain (GLS) was significantly correlated with TCRT (<italic>F</italic> 9.648, <italic>r</italic><sup>2</sup> = 0.192, standardized β = 0.331, unstandardized β = 3.567, <italic>t</italic> = 4.4429, CI: 1.976–5.157, <italic>p</italic> &lt; 0.001).</p><p><bold>Conclusion:</bold> TCRT correlates with GLS and is independently associated with cardiac deaths and MACE in HD patients.</p>