title: Relationship between QT Interval Length and Arterial Stiffness in Systemic Lupus Erythematosus (SLE): A Cross-Sectional Case-Control Study.
abstract: OBJECTIVE
  The QT interval on the electrocardiogram has been shown to be longer in patients with systemic lupus erythematosus (SLE) compared to that of the general population. The clinical significance of this finding is unknown. The aim of this study was to assess the relationship between QT interval and subclinical atherosclerosis, measured by carotid-femoral pulse-wave velocity.
  
  
  METHODS
  93 patients with SLE and 109 healthy women with similar basal characteristics were studied. All patients underwent a 12- lead electrocardiogram, and corrected QT interval (QTc) was measured using the Bazett's formula. The presence of atherosclerosis was evaluated by carotid-femoral pulse-wave velocity.
  
  
  RESULTS
  Clinical basal characteristics were similar in both groups. QTc interval was 415 ± 21.4 milliseconds in all patients, and 407 ± 19.1 milliseconds in the control group (p = 0.007). There was a positive correlation between QTc interval and carotid-femoral pulse-wave velocity (r = 0.235; p = 0.02) in patients with SLE. This association was independent of hypertension and age in a multivariate analysis.
  
  
  CONCLUSIONS
  QTc interval measured by electrocardiogram is prolonged in SLE patients; it is related to subclinical atherosclerosis, measured by carotid-femoral pulse-wave velocity. This measure may help stratify risk in routine clinical practice and select the patients that might benefit from a more aggressive therapy in the prevention of cardiovascular events.
authors.affiliation: Cardiology Clinical Management Unit, Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Rivera-López
authors.affiliation: Cardiology Clinical Management Unit, Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Jiménez-Jáimez
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: José Mario
authors.initials: JM
authors.lastname: Sabio
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Zamora-Pasadas
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Vargas-Hitos
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Josefina
authors.initials: J
authors.lastname: Martínez-Bordonado
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Nuria
authors.initials: N
authors.lastname: Navarrete-Navarrete
authors.affiliation: Intensive Care Unit. Serrania Hospital, Ronda (Málaga). Spain.
authors.forename: Ricardo Rivera
authors.initials: RR
authors.lastname: Fernández
authors.affiliation: Andalusian School of Public Health, Granada, Spain.|CIBER de Epidemiología y Salud Publica (CIBERESP), Madrid, Spain.|Instituto de Investigación Biosanitaria de Granada (Granada. ibs), Granada, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Sanchez-Cantalejo
authors.affiliation: Systemic Autoinmune Diseases Unit. Department of Internal Medicine. Granada University Hospitals; Granada Institute of Biohealth Research.Granada. Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Jiménez-Alonso
mesh_terms: D000328:Adult; D059168:Carotid Intima-Media Thickness; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008133:Long QT Syndrome / Q000209:etiology*; D008180:Lupus Erythematosus, Systemic / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D063177:Pulse Wave Analysis; D012307:Risk Factors; D059289:Vascular Stiffness