Electrocardiogram abnormalities and heart rate variability in predicting mortality and cardiovascular events among hemodialyzed patients.
OBJECTIVE
The aim of the study was to evaluate the correlation between electrocardiographic parameters and heart rate variability with cardiovascular events and mortality among chronic hemodialysis patients.


METHODS
In this prospective study, we enrolled 116 asymptomatic patients in whom we performed ambulatory 24-h electrocardiographic Holter monitoring and before and after hemodialysis electrocardiographs. We measured the interval (PR, QRS, QTc, QTc dispersion) differences on the surface electrocardiographs and obtained frequency-domain measures from Holter monitoring (VLF, LF, HF and the LF/HF ratio).


RESULTS
During the follow-up period, 13 participants died (11.2 %) and 16 (13.8 %) patients experienced a cardiovascular event. The pre-post-dialysis difference in QTc interval was the best predictor for cardiovascular events (95 % CI 0.453-0.786), while pre-dialysis QRS interval was the predictor for all-cause mortality (95 % CI 1.134-3.136). Also, both outcomes were predicted by pre-post-dialysis difference in PR interval and VLF.


CONCLUSIONS
Interval changes during hemodialysis are predictive for cardiovascular events and mortality. Autonomic dysfunction and changes in PR should be monitored routinely, particularly in patients with suspected coronary artery disease.
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania. silvia.badarau@gmail.com.
Silvia
S
Badarau
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Dimitrie
D
Siriopol
Gr. T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115, Iasi, Romania. daniela.drugus@umfiasi.ro.
Daniela
D
Drugus
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Raluca
R
Dumea
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Simona
S
Hogas
Department of Cardiology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Mihaela
M
Blaj
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Luminita
L
Voroneanu
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Angelica
A
Gramaticu
Department of Cardiology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Antoniu
A
Petris
Department of Cardiology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Alexandru
A
Burlacu
Department of Nephrology, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
Adrian
A
Covic
D000368:Aged; D002423:Cause of Death; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000503:physiopathology* / Q000628:therapy; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis; D020521:Stroke / Q000453:epidemiology
Autonomic dysfunction; Electrocardiogram; Hemodialysis; Holter monitoring; Survival