Sudden Cardiac Death (SCD) is the leading cause of cardiovascular death in dialysis patients. This review discusses potential underlying arrhythmic mechanisms of SCD in the dialysis population. It examines recent evidence from studies using implantable loop recorders and from electrophysiological studies in experimental animal models of chronic kidney disease. The review summarizes advances in the field of non-invasive electrophysiology for risk prediction in dialysis patients focusing on the predictive value of the QRS-T angle and of the assessments of autonomic imbalance by means of heart rate variability analysis. Future research directions in non-invasive electrophysiology are identified to advance the understanding of the arrhythmic mechanisms. A suggestion is made of incorporation of non-invasive electrophysiology procedures into clinical practice. Key Concepts : – Large prospective studies in dialysis patients with continuous ECG monitoring are required to clarify the underlying arrhythmic mechanisms of SCD in dialysis patients. – Obstructive sleep apnoea may be associated with brady-arrhythmias in dialysis patients. Studies are needed to elucidate the burden and impact of sleeping disorders on arrhythmic complications in dialysis patients. – The QRS-T angle has the potential to be used as a descriptor of uremic cardiomyopathy. – The QRS-T angle can be calculated from routine collected surface ECGs. Multicenter collaboration is required to establish best methodological approach and normal values. – Heart Rate Variability provides indirect assessment of cardiac modulation that may be relevant for cardiac risk prediction in dialysis patients. Short-term recordings with autonomic provocations are likely to overcome the limitations of out of hospital 24-h recordings and should be prospectively assessed.

Cardiovascular mortality is very high in chronic and end-stage kidney disease (ESKD). However, risk stratification data are lacking. Sudden cardiac deaths are among the most common cardiovascular causes of death in these populations. As a result, many studies have assessed the prognostic potential of various electrocardiographic parameters in the renal population. Recent data from studies of implantable loop recordings in haemodialysis patients from five different countries have shed light on a pre-eminent bradyarrhythmic risk of mortality. Importantly, heart block addressed by permanent pacing system was detected in a proportion of patients during the prolonged recording periods. Standard electrocardiogram is inexpensive, non-invasive and easily accessible. Hence, risk prediction models using this simple investigation tool could easily translate into clinical practice. We believe that electrocardiographic assessment is currently under-valued in renal populations. For this review, we identified studies from the preceding 10 years that assessed the use of conventional and novel electrocardiographic biomarkers as risk predictors in chronic and ESKD. The review indicates that conventional electrocardiographic markers are not reliable for risk stratification in the renal populations. Novel parameters have shown promising results in smaller studies, but further validation in larger populations is required.

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.