title: From a regional cohort of extremely low birth weight infants: cardiac function at the age of 7 years.
abstract: BACKGROUND
  The long-term impact of prematurity on cardiac structure and function has not yet been fully discovered.
  
  
  OBJECTIVE
  To assess long-term cardiac complications in the regional cohort of extremely low birth weight (ELBW) children born in 2002-2004.
  
  
  METHODS
  Eighty-one children born as ELBW infants (91% of the available cohort) with a median birth weight of 890 g (25-75th percentile: 760-950) were evaluated at the mean age of 6.7 years. The control group included 40 children born full-term, selected from one general practice in the district. Echocardiography and 24-hour ambulatory blood pressure measurements (ABPM) were performed. The primary outcome variable was the presence of cardiac complications such as left ventricular hypertrophy (LVH), diastolic dysfunction or systolic dysfunction.
  
  
  RESULTS
  LVH was diagnosed in 4/81 ELBW children and 2/40 control children (p = 1.0). Concentric remodeling was detected in 8 (10%) subjects from the ELBW group and in 2 (5%) from the control group (p = 0.49). There were no patients with diastolic or systolic dysfunction in either group. After having expressed the results of M-mode echocardiography as z-scores for body surface area (BSA), statistically significant differences were observed for right-ventricle dimension in diastole (-1.49 ± 1.25 vs. -0.31 ± 0.91; p < 0.001), LV inner dimension in diastole (-0.53 ± 1.26 vs. 0.13 ± 0.94; p = 0.01) and left atrium (-0.93 ± 1.07 vs. -0.15 ± 1.02; p < 0.01). Heart rate (HR) was significantly faster in ELBW children (92.9 ± 8.4 vs. 86.7 ± 7.4 bpm; p = 0.01 adjusted for BSA) and they also had significantly higher night-time blood pressure [mean (z-score): 1.15 vs. 0.2; p = 0.02] without nocturnal dipping (night-time dipping <10%: 13 (16.7%) vs. 2 (5.2%), p = 0.13).
  
  
  CONCLUSIONS
  No differences were found between the groups in the occurrence of cardiac complications. Ex-preterm ELBW children at age 6 may have a faster HR, smaller cardiac dimensions on echocardiography and higher nocturnal blood pressure. The clinical relevance of these findings is unknown.
authors.affiliation: Department of Pediatrics, Jagiellonian University Medical College, Cracow, Poland. kwintap@mp.pl
authors.forename: Przemko
authors.initials: P
authors.lastname: Kwinta
authors.forename: Mateusz
authors.initials: M
authors.lastname: Jagła
authors.forename: Andrzej
authors.initials: A
authors.lastname: Grudzień
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Klimek
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zasada
authors.forename: Jacek Jozef
authors.initials: JJ
authors.lastname: Pietrzyk
mesh_terms: D000367:Age Factors; D001724:Birth Weight; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018619:Echocardiography, Doppler, Pulsed; D006321:Heart / Q000254:growth & development* / Q000503:physiopathology; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D016015:Logistic Models; D015999:Multivariate Analysis; D011044:Poland; D011237:Predictive Value of Tests; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right; D020257:Ventricular Remodeling