Analysis of T-wave morphology from the 12-lead electrocardiogram for prediction of long-term prognosis in patients initiating haemodialysis.
BACKGROUND
Cardiovascular disease remains the most common cause of death in end-stage renal disease (ESRD). Recently, novel descriptors of T-wave morphology have been suggested as measures of repolarization heterogeneity and adverse prognosis in non-uraemic populations. However, whether these T-wave descriptors provide prognostic information in uraemic populations has not been examined. The present study aimed to determine the prognostic value of novel T-wave morphology variables in predicting total, cardiovascular and arrhythmia-related mortality in ESRD patients initiating haemodialysis.


METHODS
The study was a retrospective cohort of adult ESRD patients starting haemodialysis between 1998 and 2005; follow-up was until September 2006. A total of 325 patients were studied. Novel ECG variables characterizing repolarization and the T-wave loop were analysed.


RESULTS
Of 325 patients with technically analysable data, 154 (47.4%) died after a mean follow-up of 25.5+/-21.7 months. Direct comparison between cardiovascular death and non-cardiovascular death patients showed that the relative T-wave residuum (TWR) predicted cardiovascular mortality (0.20+/-0.21% vs 0.24+/-0.17%, P=0.005). In Cox modeling, relative TWR was an independent predictor of cardiovascular [relative risk (RR)=1.86; P=0.013] and arrhythmia-related mortality (RR=2.102; P=0.012).


CONCLUSIONS
The heterogeneity of myocardial repolarization, measured by the relative T-wave residuum in the ECG, appears to be an independent predictor of cardiovascular and arrhythmia-related mortality in patients initiating haemodialysis.
Lin
Chien-Yu
CY
Department of Internal Medicine of Nephrology, En Chu Kong Hospital, and Department of Internal Medicine of Cardiology, National Taiwan University Hospital, No.17 Syujhou Road, Taipei 10055, Taiwan.
Lin
Lian-Yu
LY
Chen
Pau-Chung
PC
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003710:Demography; D004562:Electrocardiography / Q000379:methods*; D006801:Humans; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000401:mortality; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D006435:Renal Dialysis; D013997:Time Factors