Electrophysiologic-histologic correlation of the cardiac specialized conduction system in two cases of single ventricle and levotransposition of the great arteries

Electrophysiologic residua and sequelae of surgery for congenital heart defects

Postoperative arrhythmias may occur in any patient who undergoes intracardiac surgery for a congenital heart defect. The correction of certain intracardiac heart defects predisposes to a large incidence of cardiac arrhythmias. Ventricular arrhythmias and conduction disturbances are seen after correction of tetralogy of Fallot, ventricular septal defect and atrioventricular canal defect. Supraventricular arrhythmias and sinus nodal dysfunction may be seen after surgery for transposition of the great arteries or atrial septal defect. The identification, evaluation and treatment of these patients are discussed.

Demonstration of abnormal proximal conduction system by His bundle electrocardiography in a patient with a single ventricle

His bundle electrocardiography in a patient with a single ventricle and 2:1 block showed the block to be proximal to the His bundle. The sinus node recovery time was normal. In addition, there was suggested evidence of a functionally and/or structurally abnormal accessory pathway. The role of His bundle electrocardiography in a patient with a single ventricle in defining the function of various portions of the conduction system was thus demonstrated.

[The clinical relevance of intraoperative electrophysiologic mapping (author's transl)]

Electrophysiological intraoperative mapping is described as a technique for identification of the specialized AV conduction system during open heart surgery; furthermore it is suitable for delineating the morphological origin of ventricular tachycardias which requre surgical therapy. The mapping technique is described with respect to its methodical aspects and illustrated by means of congenital and acquired heart disease.