Impaired cardiac autonomic nervous activity predicts sudden cardiac death in patients with operated and unoperated congenital cardiac disease.
OBJECTIVE
Sudden cardiac death is a leading cause of mortality in patients with congenital cardiac disease after surgical correction and is potentially preventable. The identification of patients at risk is therefore of major interest. We sought to assess the prognostic value of impaired cardiac autonomic nervous activity in patients with congenital cardiac disease.


METHODS
Forty-three consecutive patients with congenital cardiac disease were included in this prospective study. Parameters of heart rate turbulence and heart rate variability were calculated from Holter electrocardiograms. In addition, serum brain natriuretic peptide levels were measured. A combined end point of sudden cardiac death or nearly missed sudden cardiac death was used.


RESULTS
During a mean follow up of 27 +/- 12.7 months, 5 patients died, and another 2 were successfully resuscitated. On univariate analysis, both brain natriuretic peptide levels and parameters of heart rate variability and heart rate turbulence were associated with impaired prognosis. On multivariate analysis, pathologic heart rate turbulence was found to be the strongest independent risk stratifier (hazard ratio, 61.5; P < .001).


CONCLUSIONS
Impaired cardiac autonomic nervous activity is associated with an increased risk of sudden cardiac death in congenital cardiac disease. Our results suggest that heart rate turbulence might be superior to established markers of cardiac autonomic dysfunction, such as heart rate variability. The combined use of heart rate turbulence, heart rate variability, and markers of neurohormonal activation, such as brain natriuretic peptide, might further improve the prognostic value.
Lammers
Astrid
A
Klinik für Kinderkardiologie und angeborene Herzfehler, Deutsches Herzzentrum München, Klinik an der Technischen Universität München, Germany.
Kaemmerer
Harald
H
Hollweck
Regina
R
Schneider
Raphael
R
Barthel
Petra
P
Braun
Siegmund
S
Wacker
Annette
A
Brodherr-Heberlein
Silke
S
Hauser
Michael
M
Eicken
Andreas
A
Schmidt
Georg
G
Hess
John
J
D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D005260:Female; D006321:Heart / Q000294:innervation* / Q000503:physiopathology*; D006331:Heart Diseases / Q000150:complications / Q000151:congenital* / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D008297:Male; D011379:Prognosis; D011446:Prospective Studies