[Late XXXX in the operated interatrial communication. Analysis of sinus node function and the conduction pathways by His bundle electrocardiography].

@entity1 @entity9765 @entity118 @entity943 @entity1168 @entity130
Four hundred @entity1 with @entity118 treated surgically were reviewed. Thirty five (8.7%) developed arrhytmias post-surgery which persisted for over a year. Sinus @entity1168 was found in 10 @entity1 , nodal rhythm in 21, and atrial fibrilation and flutter in 4 @entity1 . Thirty five per cent of the @entity1 with late @entity943 developed related symptomatology. In 14 @entity1 the function of the sinus node was studied with electrical stimulation of the atrium and with His registry. The interatrial conduction time, AV node and His Purkinje were analized employing various stimulation frequencies. All the cases studied had normal intra-atrial conduction; the response of the atrio-ventricular node to increasing frequencies was normal, an the intraventricular conduction remained constant. In 8 @entity1 (52%), alterations of the sinus node were found; these consisted of prolonged post-stimulation pauses, @entity9765 and suppression of sinus automatism employing vagal procedures or through electrical stimulation. A @entity1 with severe @entity1168 detected by dynamic electrocardiography had to be treated with a permanent pacemaker. We confirm that these arrhytmias are not produced by lesions of the internodal tracts, and that an alteration of the sinus node is frequent without a concomitant lesion of the intraventricular pathway. The lesion to the nutrient artery could be due to @entity130 and/or surgically induced. The response to anticholinergic drugs was good. Prolonged observation of these @entity1 could increase the morbility of these arrythmias and raise doubts of the surgical indications in cases with moderate hemodynamic repercussion.
