Electrophysiologic cardiac function before and after surgery in children with atrioventricular canal.
Thirty-two children with atrioventricular (AV) canal underwent electrophysiologic studies: 18 underwent preoperative studies at a median age of 3 years (range 6 months to 16 years); 14 underwent postoperative studies at a median age of 4 years (range 2 to 19); and 2 underwent both preoperative and postoperative matched studies. In the preoperative group the following abnormalities were observed: first-degree AV block in 5 patients (due to internodal conduction delay in 1, AV nodal conduction delay in 2 and normal intracardiac intervals in 2); internodal conduction delay but normal PR interval in 4; and disease of the sinus node in only 1. In the postoperative group the following abnormalities were observed: first-degree AV block in 9 (due to AV nodal conduction delay in 2, His-Purkinje system conduction delay in 1, upper normal intracardiac intervals in 3 and unidentified in 3); prolongation of the right ventricular apical activation time in 11 of 13 with right bundle branch block; abnormal sinus node function in 3; and abnormal AV nodal function in 4 (1 of whom had associated sinus node disease). Atrial and ventricular functions were normal in all preoperative and postoperative patients. Electrophysiologic dysfunction is rare in preoperative patients with AV canal; in postoperative patients electrophysiologic abnormalities occur in 38% and involve the sinus and AV nodes in 19 and 25%, respectively.
A
A
Fournier
M L
ML
Young
O L
OL
Garcia
D F
DF
Tamer
G S
GS
Wolff
D000293:Adolescent; D016275:Atrial Function; D001283:Atrioventricular Node / Q000503:physiopathology / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006325:Heart Atria / Q000601:surgery; D006330:Heart Defects, Congenital / Q000503:physiopathology* / Q000601:surgery; D006352:Heart Ventricles / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D007223:Infant; D008297:Male; D012849:Sinoatrial Node / Q000503:physiopathology