title: Electrocardiographic findings in chronic hemodialysis patients.
abstract: BACKGROUND
  Cardiovascular disease is the leading cause of mortality among patients on dialysis. When considering all causes of death, about 30% are classified as cardiac arrest, death of unknown cause or cardiac arrhythmia. The increasing time of ventricular depolarization and repolarization, measured non-invasively by measuring the QT interval on the electrocardiogram at rest, has emerged as a predictor of complex ventricular arrhythmias, a major cause of sudden cardiac death.
  
  
  OBJECTIVE
  To determine the electrocardiographic alterations present in hemodialysis (HD) patients, measuring the QT interval and its relationship with clinical and laboratory variables.
  
  
  METHODS
  Patients above 18 years on dialysis were approached to participate in the study and, after consent, were submitted to the examination of 12-lead electrocardiogram. Clinical data were reviewed to assess the presence of comorbidities, as well as anthropometric and blood pressure measures. Blood samples were collected to determinate hemoglobin and serum levels of calcium, phosphorus and potassium.
  
  
  RESULTS
  One hundred and seventy nine patients were included in the study. The majority of the patients were male (64.8%) and white (54.7%); the average age was 58.5 ± 14.7 years old. About 50% of all patients had, at least, one electrical conduction disturb. About 50% of all patients had QTc prolongation and experienced a significant increase in the frequency of Left Ventricular Hypertrophy (LVH), changes of the cardiac rhythm and bundle branch blocks, and a lower body mass index (BMI), when compared with normal QTc interval patients.
  
  
  CONCLUSIONS
  Patients with chronic kidney disease (CKD) on hemodialysis had high frequency of abnormal electrocardiographic findings, including a high prevalence of patients with prolonged QTc interval. This study also found a significant association between prolonged QTc interval and the presence of Diabetes and lower values of BMI.
authors.affiliation: Hospital de Caridade São Vicente de Paulo, Jundiaí, SP.
authors.forename: Luís Henrique
authors.initials: LH
authors.lastname: Bignotto
authors.forename: Marina Esteves
authors.initials: ME
authors.lastname: Kallás
authors.forename: Rafael Jorge Teixeira
authors.initials: RJ
authors.lastname: Djouki
authors.forename: Marcela Mayume
authors.initials: MM
authors.lastname: Sassaki
authors.forename: Guilherme Ota
authors.initials: GO
authors.lastname: Voss
authors.forename: Cristina Lopez
authors.initials: CL
authors.lastname: Soto
authors.forename: Fernando
authors.initials: F
authors.lastname: Frattini
authors.forename: Flávia Silva Reis
authors.initials: FS
authors.lastname: Medeiros
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology*; D003430:Cross-Sectional Studies; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis