title: Significant QT interval prolongation and long QT in young adult ex-preterm newborns with extremely low birth weight.
abstract: BACKGROUND
  The survival rate for extremely low birth weight (ELBW) infants born preterm is on an increasing upward trend, despite the possibility of neuro-cerebral consequences in later life. To date, scarce information is available on the effect of extreme prematurity on cardiovascular system.
  
  
  OBJECTIVE
  To verify the presence of standard echocardiographic and ECG alterations in ex-ELBW young healthy adults.
  
  
  METHODS
  A color Doppler echocardiogram and an ECG were performed on 24 ex-ELBW (4 males and 20 females; mean: 23.2 ± 3.3 years), compared with 24 healthy subjects born at term (C). ECG parameters examined: PR, QT, QT(c), and QT dispersion (QT(d)). Gestational age, birth weight, and duration of stay in neonatal intensive care unit were obtained from clinical records.
  
  
  RESULTS
  Transthoracic echocardiography did not reveal differences between ex-ELBW and C, while a significant difference was displayed by ex-ELBW with regard to PR (141.5 ± 13.4 ms vs. 164.2 ± 24.0 ms, p < 0.0003), QT(c) (417.0 ± 23.6 ms vs. 369.9 ± 19.5 ms, p =0.00001), and QT(d) (30.4 ± 14.1 ms vs. 24.6 ± 8.2 ms, p < 0.00001). In two patients (8.3%), QT(c) exceeded the upper limit of normal range. A statistically significant inverse correlation was observed between QT(c) and gestational age (r = -0.67, p < 0.0003).
  
  
  CONCLUSIONS
  QT(c) and QT(d) in ex-ELBW were found to be at the upper limit of normal range and correlated with gestational age and birth weight; in two cases, QT(c) exceeded the upper limit. This study, irrespective of the pathophysiological mechanism involved, underlines a potential risk for ex-ELBW of developing ventricular arrhythmias when using drugs capable of prolonging QT interval.
  
  
  CONCLUSIONS
  QT(c) and QT(d) in young adults previously born preterm with an ELBW (401-1000 g) were generally found to be at the upper limit of normal range and correlated with gestational age and birth weight. This finding underlines a potential risk for ex-ELBW of developing ventricular arrhythmias when using drugs capable of prolonging QT interval.
authors.affiliation: Department of Cardiovascular and Neurological Sciences, University of Cagliari, Cagliari, Italy. piercard@inwind.it
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Bassareo
authors.forename: Vassilios
authors.initials: V
authors.lastname: Fanos
authors.forename: Melania
authors.initials: M
authors.lastname: Puddu
authors.forename: Christian
authors.initials: C
authors.lastname: Cadeddu
authors.forename: Marta
authors.initials: M
authors.lastname: Balzarini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mercuro
mesh_terms: D000328:Adult; D032721:Adult Children; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D015331:Cohort Studies; D004562:Electrocardiography / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D052577:Infant, Extremely Low Birth Weight / Q000502:physiology; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D015996:Survival Rate; D013997:Time Factors; D055815:Young Adult