Comprehensive Electrocardiographic Analysis of Lead Exposed Workers: An Arrhythmic Risk Assessment Study.
BACKGROUND
To evaluate electrocardiographic parameters which are related with atrial and ventricular arrhythmias measured from 12-lead surface electrocardiogram (ECG) in workers occupationally exposed to lead.


METHODS
Sixty lead-exposed workers and 60 healthy controls were enrolled. Twelve-lead surface ECG was recorded and measurements of P wave durations (Pmax, Pmin) and P wave dispersion (PWD), QT durations and dispersion (QTd), corrected QT (QTc), Tp-e interval, and Tp-e/QT ratio were analyzed.


RESULTS
The lead-exposed and control groups were similar with respect to baseline demographic, laboratory, and transthoracic echocardiographic indices. PWD (26.3 ± 9.7 vs 22.0 ± 9.0 ms, P = 0.014), Pmin (89.9 ± 13.8 vs 79.2 ± 10.1 ms, P < 0.001), and Pmax (116.2 ± 15.0 vs 101.2 ± 14.2 ms, P < 0.001), QT maximum (377.0 ± 27.6 vs 364.9 ± 28.5 ms, P = 0.02), QTd (38.4 ± 16.5 vs 30.5 ± 12.4 ms, P = 0.004), Tp-e interval (78.9 ± 16.5 vs 70.3 ± 14.5 ms, P = 0.003), and Tp-e/QT ratio (0.22 ± 0.04 vs 0.20 ± 0.04, P = 0.013) were significantly higher in lead-exposed workers. QT minimum and QTc values did not differ significantly. QT maximum, QTd, and Tp-e/QT ratio were correlated with urine lead level and Tp-e interval was correlated with both blood and urine lead levels.


CONCLUSIONS
Lead-exposed workers have a higher risk for atrial and ventricular arrhythmias even without overt cardiac diseases compared with healthy subjects. These workers should be followed closely for adverse cardiovascular outcomes especially arrhythmias.
Department of Cardiology, Ankara Occupational Diseases Hospital, Ankara, Turkey.
Ugur N
UN
Karakulak
Department of Clinical Toxicology, Ankara Occupational Diseases Hospital, Ankara, Turkey.
Omer H
OH
Yilmaz
Department of Clinical Toxicology, Ankara Occupational Diseases Hospital, Ankara, Turkey.
Engin
E
Tutkun
Department of Clinical Toxicology, Ankara Occupational Diseases Hospital, Ankara, Turkey.
Meside
M
Gunduzoz
Department of Cardiology, Ankara Occupational Diseases Hospital, Ankara, Turkey.
Emine
E
Ercan Onay
D000328:Adult; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000503:physiopathology*; D053840:Brugada Syndrome / Q000175:diagnosis / Q000503:physiopathology; D000075224:Cardiac Conduction System Disease; D003430:Cross-Sectional Studies; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D007855:Lead Poisoning / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D016273:Occupational Exposure; D018570:Risk Assessment
P wave dispersion; QT interval; Tp-e interval; Tp-e/QT ratio; lead exposure