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

Abstract

Background: 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. Methods: 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. Results: 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, p = 0.029, CI: 1.002–1.030 and HR 3.506, CI: 1.118–10.995, p = 0.031 respectively) and with MACE dichotomized at 100° (HR 1.902, CI: 1.046–3.459; p = 0.035). In multivariate regression analysis including baseline parameters, echocardiographic global longitudinal strain (GLS) was significantly correlated with TCRT ( F 9.648, r 2 = 0.192, standardized β = 0.331, unstandardized β = 3.567, t = 4.4429, CI: 1.976–5.157, p < 0.001). Conclusion: TCRT correlates with GLS and is independently associated with cardiac deaths and MACE in HD patients.

Heat Shock Protein 27 Levels Predict Myocardial Inhomogeneities in Hemodialysis Patients

“…Abnormalities in depolarization mirror structural abnormalities, while those in repolarization reflect changes in regional action potential duration and the direction of repolarization sequence associated with electrical instability and SCD. QRS-T angle is an established marker of global repolarization heterogeneity, possibly related to underlying structural and functional myocardial abnormalities [ 3 , 6 – 8 , 11 , 14 – 16 , 18 ]. In our study, abnormal QRS-T angle was found in 30% of HD patients.…”

Sudden Cardiac Death in Dialysis: Arrhythmic Mechanisms and the Value of Non-invasive Electrophysiology

“…A pubmed search using the terms HRV and dialysis returns 122 studies with the first one published already in 1986 (Forsstrom et al, 1986). Abnormal HRV indices have been associated with all cause (Hayano et al, 1999; Oikawa et al, 2009; Suzuki et al, 2012; Chen et al, 2016; Ng et al, 2017; Poulikakos et al, 2018) and cardiovascular mortality (Hayano et al, 1999; Fukuta et al, 2003; Oikawa et al, 2009; Chen et al, 2016) in east Asian HD patients and in one small study including predominantly Caucasian HD patients (Skampardoni et al, 2018a). Depressed HRV has also been associated with all cause (Pei et al, 2015; Chiang et al, 2016) and cardiovascular (Hayano et al, 1999) mortality in east Asian patients receiving peritoneal dialysis.…”

“…The QRS-T angle is calculated numerically, is reproducible (Poulikakos et al, 2013; Hnatkova et al, 2017) and thus suitable for risk stratification purposes. A larger QRS-T angle has been shown to predict SCD (de Bie et al, 2013b; Tereshchenko et al, 2016), cardiovascular mortality (Skampardoni et al, 2018a) and all cause mortality (Tereshchenko et al, 2016; de Bie et al, 2013b; Poulikakos et al, 2018) in different cohorts of predominantly African (Tereshchenko et al, 2016) and Caucasian (Sallam et al, 2015; Poulikakos et al, 2018; Skampardoni et al, 2018a) dialysis patients. However, one study in 325 Taiwanese HD patients (Lin et al, 2007) did not find a significant association between magnitude of QRS-T angle and outcomes.…”

“…An increased QRS-T angle has been associated with echocardiographic left ventricular hypertrophy (Tereshchenko et al, 2016), decreased global longitudinal strain (Skampardoni et al, 2018a), lower left ventricular ejection fraction, and with left ventricular systolic dyssynchrony (de Bie et al, 2013a) in different cohorts of HD patients. It has also been associated with increased coronary artery calcium burden, and elevated Troponin T levels in patients receiving peritoneal dialysis (Jaroszynski et al, 2009).…”

Correlation between Age and Electrical Axes of the Heart in Adult Nigerians

“…T wave axis has also been shown to be a strong predictor of cardiac morbidity, cardiac mortality and all-cause mortality [3] [4] [5] [6]. QRS-T angle, which is the angle between QRS axis and T wave axis, is a strong predictor of cardiac morbidity, cardiac mortality and all-cause mortality [4] [7] [8]. Since QRS-T angle is the difference between the QRS axis and T wave axis [9] QRS-T angle indirectly indicates the prognostic value of QRS axis.…”