title: Evaluation of the North Star Ambulatory Assessment scale and cardiac abnormalities in ambulant boys with Duchenne muscular dystrophy.
abstract: OBJECTIVE
  We evaluated ambulatory patients with Duchenne muscular dystrophy from the cardiovascular standpoint and studied the correlation between the results of electrocardiographic (ECG) findings, left ventricular ejection fraction (LVEF), troponin T and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels and patients' North Star Ambulatory Assessment scores.
  
  
  METHODS
  Fifty patients of ages 6-12 (8.9 ± 2.8) were enrolled in this cross-sectional study. Cardiac evaluation included electrocardiography, echocardiography and cardiac enzyme tests.
  
  
  RESULTS
  North Star scores ranged from 6/34 to 34/34. Twenty-eight patients (56%) had ECG changes. The most frequently seen ECG abnormalities were short PR interval (14%, n= 7), right ventricular hypertrophy (16%, n= 8), prolonged QTc interval (10%, n= 5), prominent Q wave (10%, n= 5) and T wave inversion (44%, n= 22). In 10 patients (20%), LVEF was below 55%, troponin T and NT-proBNP levels were significantly elevated (P= 0.003 and P < 0.001, respectively). When North Star scores were compared to patients' age, enzyme levels, ECG and echocardiographic results, we discovered negative correlation with age (P < 0.001) and troponin T levels (P= 0.02) and positive correlation with LVEF (P= 0.02).
  
  
  CONCLUSIONS
  Patients with North Star scores of ≤16 are more at risk of developing cardiomyopathies. Troponin T is a cardiac index that can be used for evaluating myopathic patients and it seems to be correlated with the proBNP levels and LVEF values.
authors.affiliation: Department of Pediatric Cardiology, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey. yakupergul77@hotmail.com
authors.forename: Yakup
authors.initials: Y
authors.lastname: Ergul
authors.forename: Baris
authors.initials: B
authors.lastname: Ekici
authors.forename: Kemal
authors.initials: K
authors.lastname: Nisli
authors.forename: Burak
authors.initials: B
authors.lastname: Tatli
authors.forename: Fatih
authors.initials: F
authors.lastname: Binboga
authors.forename: Gonul
authors.initials: G
authors.lastname: Acar
authors.forename: Meral
authors.initials: M
authors.lastname: Ozmen
authors.forename: Rukiye Eker
authors.initials: RE
authors.lastname: Omeroglu
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology*; D002648:Child; D003430:Cross-Sectional Studies; D004452:Echocardiography; D004562:Electrocardiography; D006801:Humans; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000150:complications* / Q000503:physiopathology; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D012720:Severity of Illness Index; D013318:Stroke Volume; D020107:Troponin T / Q000097:blood
chemical_list: D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain