title: Evidence for cardiovascular autonomic dysfunction in neonates with coarctation of the aorta.
abstract: BACKGROUND
  Coarctation of the aorta (CoA) is associated with hypertension and abnormalities of blood pressure control, which persist after late repair. Assumptions that neonatal repair would prevent development of blood pressure abnormalities have not been supported by recent data. We hypothesized that early pathological adjustment of autonomic cardiovascular function may already be established in the neonate with coarctation.
  
  
  RESULTS
  We studied 8 otherwise well neonates with simple CoA and compared measures of spontaneous baroreflex sensitivity, heart rate variability, and blood pressure variability with 13 healthy newborn babies. Spontaneous baroreflex sensitivity was calculated with sequence methodology from an ECG, and noninvasive blood pressure was recorded with a Portapres. Heart rate variability was determined with time- and frequency-domain measures. Blood pressure variability was measured in the frequency domain. In comparison with normal controls, neonates with CoA had raised blood pressure (78.9+/-3.8 versus 67.1+/-2.1 mm Hg), depressed baroreflex sensitivity (8.7+/-1.5 versus 13.8+/-1.1 ms/mm Hg), reduced heart rate variability (total power 16.5+/-3.1 versus 31.5+/-2.2 ms2), and an increase in the high-frequency component of blood pressure variability (3.1+/-0.3 versus 2.2+/-0. 2 mm Hg2). This is not the pattern expected if neonates with CoA simply had subclinical cardiac failure.
  
  
  CONCLUSIONS
  These data suggest that infants with CoA already show signs of pathological adjustment of autonomic cardiovascular homeostasis. Further longitudinal studies are required to determine whether these alterations play a role in the increased risk of late hypertension in these patients.
authors.affiliation: Department of Clinical Sciences at South Bristol, School of Medical Sciences, Bristol Heart Institute, University of Bristol, Bristol, United Kingdom.
authors.forename: Jaimie W
authors.initials: JW
authors.lastname: Polson
authors.forename: Naomi
authors.initials: N
authors.lastname: McCallion
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Waki
authors.forename: Gareth
authors.initials: G
authors.lastname: Thorne
authors.forename: Mark A
authors.initials: MA
authors.lastname: Tooley
authors.forename: Julian F R
authors.initials: JF
authors.lastname: Paton
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Wolf
mesh_terms: D001017:Aortic Coarctation / Q000150:complications / Q000503:physiopathology*; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000209:etiology* / Q000503:physiopathology; D017704:Baroreflex / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000379:methods; D015924:Blood Pressure Monitors; D002408:Catheters, Indwelling; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000209:etiology* / Q000503:physiopathology; D007231:Infant, Newborn; D008297:Male; D011311:Pressoreceptors / Q000502:physiology; D012021:Reflex, Abnormal; D015203:Reproducibility of Results