[Disorders of the rhythm and conduction in patients operated on for a total correction of tetralogy of Fallot].

The purpose of this paper is to analyze the incidence of arrhythmias and conduction disturbances in 81 patients after total surgical repair of tetralogy of Fallot. The study was done at the National Institute of Cardiology "Ignacio Chávez" from 1974 to 1989. Sixty five patients (78.9%) developed a pattern of right bundle block and ten patients (12.3%) had additional left anterior hemiblock following surgery. Two patients had complete heart block so pacemaker was implanted. The incidence of serious ventricular arrhythmias was found in 11 patients often polymorphic ventricular premature complexes. One case sustained monomorphic ventricular tachycardia. Electrophysiological study demonstrated that it source was the scar of the right ventricle outflow tract. This tachycardia is now under control with specific antiarrhythmic therapy.