ATRIAL BAFFLE PROCEDURES FOR COMPLETE TRANSPOSITION OF THE GREAT-ARTERIES - NATURAL COURSE OF SINUS NODE DYSFUNCTION AND RISK-FACTORS FOR DYSRHYTHMIAS AND SUDDEN-DEATH

359 patients after the Mustard (275) or Senning (84) operations for tr ansposition of the great arteries were followed-up for a mean of 103.7 (range 0.4 to 204) months. 259 patients had postoperative 24-h Holter recordings. In 129 Mustard children serial (mean 4.4) postoperative H olter recordings were available for evaluation. Criteria based on Holt er and scalar electrocardiograms at normal sinus node functions were u sed for rhythm analysis. Postoperative dysrhythmias appeared in 70% of the patients: sinus node dysfunction in 62.8%, second or third degree atrioventricular block in 3.2%, sustained atrial tachycardia or atria l flutter in 4.5%, and significant ventricular arrhythmia (Lown 2-5) i n 21.4%. The prevalence of sinus node dysfunction increased slightly f rom 50.8% during the first 2 postoperative years to 64.4% in patients more than 10 years postoperatively. Fifteen patients (4.2%) died sudde nly during follow-up. By multivariate analysis severe tricuspid regurg itation and/or right ventricular dysfunction and uncontrolled supraven tricular tachydysrhythmias were identified as the two significant risk factors for sudden death.