Increased Repolarization Heterogeneity is Associated with Increased Mortality in Hemodialysis Patients

Arrhythmic death is the leading cause of mortality among End-Stage Renal Disease patients but determining which of these patients are at sufficient risk to warrant defibrillator therapy remains an open question. To test whether ECG parameters reflecting ventricular repolarization could help risk stratify these patients, we performed a prospective observational study involving 50 chronic hemodialysis patients. Entrance criteria included age over 40 and the presence of either diabetes or hypertension. Holter recordings were performed at the onset of a dialysis treatment and continued for 48 hrs (until the next session) and ECG parameters were derived from this data. During the 13 month follow up period, 8 patients died, 3 of cardiac causes. Despite the small numbers in this pilot study, significant increases in VPC frequency and T-wave complexity were observed between survivors and non-survivors during dialysis while significant increases in QTc interval and QRS-T angle were seen between these groups in the hours following treatment. If these results can be confirmed in larger trials, they may contribute importantly to risk stratification in these patients.