Signal averaged electrocardiography in infants and children with congenital heart disease.
Forty-four patients with congenital cardiac disease underwent surface averaged electrocardiography using a high resolution purpose built module. Twelve patients had complete transposition of the great vessels, 14 had tetralogy of Fallot, 5 had ventricular septal defects, 6 atrial septal defects, 3 atrioventricular septal defects and 4 patients had miscellaneous non-structural abnormalities. All patients with structural disorders underwent corrective or palliative surgery. The aim of the study was to examine the feasibility of the method and its usefulness in detecting His potentials and delayed potentials in the ST segment. A His potential was recorded in 30 patients (68%) with an amplitude ranging from 1.25 to 8.25 microV. Delayed potentials were recorded in only 1 patient with frequent ventricular premature beats. This technique may be useful in assessing intraventricular conduction times in patients with bundle branch block and/or axis deviation especially those who are at risk from intermittent complete AV block after surgical intervention. Detection of delayed potentials may allow better assessment of post-operative risk of ventricular arrhythmias in patients who have undergone ventricular surgery.
D002036:Bundle of His / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D006329:Heart Conduction System / Q000503:physiopathology*; D006330:Heart Defects, Congenital / Q000503:physiopathology*; D006339:Heart Rate; D006344:Heart Septal Defects, Atrial / Q000503:physiopathology; D006345:Heart Septal Defects, Ventricular / Q000503:physiopathology; D006801:Humans; D007223:Infant; D013771:Tetralogy of Fallot / Q000503:physiopathology; D014188:Transposition of Great Vessels / Q000503:physiopathology