title: Automated Functional Imaging by 2D Speckle Tracking Echocardiography Reveals High Incidence of Abnormal Longitudinal Strain in a Cohort of Pediatric Oncology Patients.
abstract: BACKGROUND
  Automated functional imaging (AFI) was introduced to two-dimensional speckle-tracking echocardiography to facilitate strain assessment in the clinical settings. In patients treated with cardiotoxic anthracyclines, AFI may be helpful in the detection of early myocardial injury when left ventricular ejection fraction (LVEF) remains normal.
  
  
  METHODS
  We retrospectively assessed feasibility of AFI in 143 echocardiograms on 102 subjects aged 0.4-22 years (mean 12.3) obtained over a 12-month period. We computed a Z-score for apical four-chamber longitudinal strain using published normal data to assess for abnormal strain in patients with and without previous exposure to anthracyclines.
  
  
  RESULTS
  AFI was feasible in 95.1% of echocardiograms, with low inter- and intraobserver variability. There was a statistically significant association between abnormal longitudinal strain Z-score (SZ < -2.0) and depressed LVEF (<55%, P < 0.001). However, 46% of echocardiograms with normal LVEF had abnormal SZ; half of which had no prior anthracycline exposure. The correlation between SZ and LVEF was strongest in subjects exposed to anthracyclines (r(2) = 0.12, P < 0.01). Increasing age was associated with decreasing SZ. Total cumulative dose, after adjusting for age, was inversely associated with SZ (r(2) = 0.42, P < 0.001). Time from last dose of anthracycline had no significant association with SZ.
  
  
  CONCLUSIONS
  AFI is highly feasible in the clinical settings. The observed high prevalence of abnormal longitudinal strain in our cohort emphasizes the importance of obtaining baseline measurements prior to anthracycline treatment. The effects of anthracycline on longitudinal strain may be dose and age dependent, with younger children less likely to show abnormalities.
authors: Department of Pediatric Cardiology, Taussig Heart Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: Jade C
authors: JC
authors: Tran
authors: Departments of Oncology and Pediatrics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: Kathy
authors: K
authors: Ruble
authors: Departments of Oncology and Pediatrics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: David Mark
authors: DM
authors: Loeb
authors: Departments of Oncology and Pediatrics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: Allen R
authors: AR
authors: Chen
authors: Department of Pediatric Cardiology, Taussig Heart Center, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors: William Reid
authors: WR
authors: Thompson
mesh_terms: D000293:Adolescent; D018943:Anthracyclines / Q000009:adverse effects*; D000970:Antineoplastic Agents / Q000009:adverse effects*; D066126:Cardiotoxicity / Q000000981:diagnostic imaging* / Q000453:epidemiology; D002648:Child; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006321:Heart / Q000187:drug effects*; D006801:Humans; D015994:Incidence; D008297:Male; D015588:Observer Variation; D011859:Radiography; D012189:Retrospective Studies
chemical_list: D018943:Anthracyclines; D000970:Antineoplastic Agents
keywords: anthracyclines; automated functional imaging; chemotherapy; heart failure; speckle tracking echocardiography; strain