P1481strain Repolarisation on Ecg, Not Left Ventricular Mass, Associates With Cardiovascular Outcomes in a Prospective Cohort of Haemodialysis Patients

Abstract

Background and Aims Cardiovascular disease is common in chronic and end stage kidney disease. Left ventricular hypertrophy (LVH) has been identified as contributor to cardiovascular risk in this population. The aim of the study was to assess whether the combined use of electrocardiography and echocardiography in assessing LVH in a haemodialysis population can provide improved risk stratification. Method Prospective study of 192 prevalent maintenance haemodialysis ( HD) patients 12 lead ECGs were performed on a mid week non –dialysis day. Electrocardiographic strain was defined as a down slopping convex ST segment with inverted T waves in leads V5 and / or V6. Transthoracic echocardiographic was performed immediately after ECG .LV mass was indexed to body surface area (LVMIBSA). LVH was determined if LVMI >116g/m2 for male patients, and >100g/m2 for female patients. The primary study endpoint was major cardiac events (MACE). A secondary endpoint was all cause mortality. Results 192 patients included in the final analysis, 137 (71.4%) male.. The mean ejection fraction (EF) was 60.6± 11.1 % and the mean LVMI (BSA) was 115.0± 36.8 g/m2. During a mean follow up period of 2.4 ± 1.0 years, 50 patients reached a MACE end point and 62 patients died. On univariate Cox regression analysis, the factors associated with MACE were the presence of ECG strain (HR 2.961, CI: 1.254 – 6.990, p= 0.013)) URR (HR 0.968, CI: 0.942 – 0.994, p=0.015) and history of CAD (HR: 2.397 CI: 1.363 -4.2515, p= 0.002). In multivariate Cox regression analysis adjusting for baseline cardiovascular phenotype and dialysis parameters ECG strain remained significantly associated with MACE. Conclusion The presence of electrocardiographic strain increases the risk for MACE independently of LVH in haemodialysis patients. ECG strain has potential to be a simple bedside prognostic biomarker and even therapeutic target in haemodialysis patients.