Results of exercise testing at a mean age of 10 years after neonatal arterial switch operation.
OBJECTIVE
This prospective follow-up study investigated long-term exercise capacity at a mean age of 10 y after neonatal arterial switch operation for transposition of the great arteries in a large group of homogeneous unselected children.


METHODS
56 asymptomatic children, aged 7.9-14.3 y (10.5 +/- 1.6, mean +/- SD), were examined with respect to exercise tolerance, electrocardiographic (ECG) response and activity of biochemical markers for myocardial injury. The protocol included standard electrocardiography, M-mode and two-dimensional echocardiography at rest, a Bruce walking treadmill test to voluntary exhaustion, and determination of cardiac troponin I and T, creatine kinase and myoglobin from venous blood samples at rest and 4 h after exercise. Heart rate, blood-pressure response to exercise stress and endurance time were compared with published results of age-matched normal children.


RESULTS
54 patients (96.4%) had normal exercise capacity; a reduction in 2 patients was not due to cardiac disease. Heart rate and systolic blood pressure rose significantly between rest and peak exercise and did not differ from normal controls, whereas diastolic blood pressure was lower. ECG remained normal at rest and on exercise in 54 children (96.4%). Serum values of cardiac troponin I and T, creatine kinase and myoglobin were normal at rest and after exercise in all patients.


CONCLUSIONS
The study demonstrates excellent long-term exercise capacity after neonatal arterial switch operation. Exercise testing is a useful and non-invasive screening method to detect patients with clinically relevant exercise-induced myocardial ischaemia and should be routinely performed in growing patients.
Hövels-Gürich
H H
HH
Department of Paediatric Cardiology, University Hospital, Aachen University of Technology, Aachen, Germany. hhoevels-guerich@ukaachen.de
Kunz
D
D
Seghaye
M- C
M
Miskova
M
M
Messmer
B J
BJ
von Bernuth
G
G
D000293:Adolescent; D006348:Cardiac Surgical Procedures; D002648:Child; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D013997:Time Factors; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*