title: Cardiac strain findings in children with latent rheumatic heart disease detected by echocardiographic screening.
abstract: BACKGROUND
  Identification of patients with latent rheumatic heart disease by echocardiography presents a unique opportunity to prevent disease progression. Myocardial strain is a more sensitive indicator of cardiac performance than traditional measures of systolic function.
  
  
  OBJECTIVE
  The objective of this study was to test the hypothesis that abnormalities in myocardial strain may be present in children with latent rheumatic heart disease.
  
  
  METHODS
  Standard echocardiography images with electrocardiogram gating were obtained from Ugandan children found to have latent rheumatic heart disease as well as control subjects. Traditional echocardiography measures of systolic function were obtained, and offline global longitudinal strain analysis was performed. Comparison between groups was performed using strain as a continuous (Mann-Whitney U-test) and categorical (cut-off 5th percentile for age) variable.
  
  
  RESULTS
  Our study included 14 subjects with definite rheumatic heart disease, 13 with borderline rheumatic heart disease, and 112 control subjects. None of the subjects had abnormal left ventricular size or ejection fraction. Global longitudinal strain was lower than the 5th percentile in 44% of the subjects with any rheumatic heart disease (p=0.002 versus controls) and 57% of the subjects with definite rheumatic heart disease (p=0.03). The mean absolute strain values were significantly lower when comparing subjects with any rheumatic heart disease with controls (20.4±3.95 versus 22.4±4.35, p=0.025) and subjects with definite rheumatic heart disease with controls (19.9±4.25 versus 22.4±4.35, p=0.033).
  
  
  CONCLUSIONS
  Global longitudinal strain is decreased in subjects with rheumatic heart disease in the absence of abnormal systolic function. Larger studies with longer-term follow-up are required to determine whether there is a role for strain to help better understand the pathophysiology of latent rheumatic heart disease.
authors.affiliation: 1Division of Cardiology,Children's National Health System,Washington,District of Columbia,United States of America.
authors.forename: Andrea
authors.initials: A
authors.lastname: Beaton
authors.affiliation: 1Division of Cardiology,Children's National Health System,Washington,District of Columbia,United States of America.
authors.forename: Hedda
authors.initials: H
authors.lastname: Richards
authors.affiliation: 1Division of Cardiology,Children's National Health System,Washington,District of Columbia,United States of America.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ploutz
authors.affiliation: 2Division of Pediatric Cardiology,Johns Hopkins University,Baltimore,Maryland,United States of America.
authors.forename: Lasya
authors.initials: L
authors.lastname: Gaur
authors.affiliation: 3Department of Pediatrics,Gulu University,Gulu,Uganda.
authors.forename: Twalib
authors.initials: T
authors.lastname: Aliku
authors.affiliation: 4Uganda Heart Institute,Mulago Hospital,Kampala,Uganda.
authors.forename: Peter
authors.initials: P
authors.lastname: Lwabi
authors.affiliation: 5Division of Cardiology,University of Michigan,Mott Children's Hospital,Ann Arbor,Michigan,United States of America.
authors.forename: Greg
authors.initials: G
authors.lastname: Ensing
authors.affiliation: 1Division of Cardiology,Children's National Health System,Washington,District of Columbia,United States of America.
authors.forename: Craig
authors.initials: C
authors.lastname: Sable
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D018450:Disease Progression; D004452:Echocardiography / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012214:Rheumatic Heart Disease / Q000175:diagnosis*; D013599:Systole; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Rheumatic heart disease; echocardiographic screening; myocardial strain