The prognostic value of electrocardiographic estimation of left ventricular hypertrophy in dialysis patients

BACKGROUND: Left ventricular hypertrophy (LVH) is associated with poor cardiovascular outcome in CKD. Electrocardiogram (ECG) is low-cost but infrequently used to assess presence of LVH in dialysis patients. The aim of this study was to establish which ECG-determined LVH method is most sensitive in dialysis patients, and also most predictive of death.

METHODS: This was a longitudinal observational study in dialysis patients from a single center, undergoing interval ECGs. Fourteen methods of ECG LVH assessment were compared. Survival was also compared between four LVH evolutionary categories: persistent LVH; new LVH; LVH regression; and no LVH.

RESULTS: The study included 418 dialysis patients (46.3% women, mean age 51 years, mean follow up 67 months, 76 deaths, 37 cardiovascular deaths). LVH prevalence varied according to method (range 13.4-41.9%). No measurement predicted all-cause mortality. After Cox regression, there was an independent association between LVH and cardiovascular mortality using Novacode (HR = 3.04; 95% [CI] = 1.11-8.28, P < 0.05), but not with other methods. Patients with persistent ECG changes of LVH had increased risk of cardiovascular mortality compared to other LVH evolutionary categories (P < 0.044).

CONCLUSIONS: ECG scoring of LVH can be predictive of cardiovascular mortality. The Novacode method, based on repolarization abnormalities, is a better predictor than standard ECG techniques that are based on voltage criteria. Novacode LVH estimation at dialysis initiation may prove to be a noninvasive and cost-effective bedside tool for cardiovascular risk stratification in patients receiving dialysis.