O104 Influence of the Long Interdialytic Break on the Incidence of Serious Arrhythmias and Sudden Cardiac Death in Patients with Chronic Kidney Disease (CKD) undergoing Haemodialysis

Abstract

Introduction: Chronic kidney disease (CKD) patients on haemodialysis (HD) have a high risk of sudden cardiac death (SCD). Traditional SCD risk factors donot adequately explain this but a unique risk factor may be a longer interval between HD sessions (interdialytic period, IDP). Inherent in conventional HD (thrice-weekly) are two 48-hour (short) breaks and one 72-hour (long) break between the start of HD sessions. Changes in electrolyte balance, ventricular repolarization (VR) and autonomic tone (AT) may be more profound after the longer IDP. Objectives:We used an implantable loop recorder (ILR) to define the incidence and timing of significant arrhythmias in a HD population, comparing the impact of the long vs short IDP (event time distribution-ETD). We used Ambulatory 24-hour Holter monitoring to evaluate markers of arrhythmic risk according to ETD. Methods: 50 CKD patients undergoing thrice-weekly conventional HD were recruited & underwent ILR insertion with regular fortnightly device follow-up. Pts with left ventricular ejection fraction 16 beats <30sec) in 7 (14%). The combined primary end point occurred in 14 pts (28%) with 385/615 (63%) events occurring during the long IDP (p<0.001). No episodes of long QT related polymorphic VT were observed.