Rhythm and conduction disturbances in patients with Ebstein's anomaly

Objective: The aim of the study was to evaluate arrhythmias in Ebstein's anomaly before and after surgery. Methods: Data on 32 patients with Ebstein's anomaly were analyzed retrospectively. We evaluated the surface 12-lead ECG and Holter's monitoring data. Results: The age of the patients varied from 1 to 47 years (mean, 16.5). Before surgery, commonly the sinus rhythm was observed in 96% and sinus tachycardia in 6% of patients. WPW syndrome was diagnosed in 12.5% of cases. Before surgery, commonly intraventri-cular conduction disorders were observed: incomplete right bundle block for 34% and complete right bundle block for 9% of patients. An atrioventricular block of various degrees was found for 15% and atrial fibrillation for 9% of patients. After surgery, premature ventricular beats were observed in 69% and premature supraventricular beats in 46% of patients. In 30% of patients, atrioventricular block of various degrees was observed. Sick sinus syndrome was diagnosed in 23% of patients. After surgery, "incision" paroxysmal tachycardia was diagnosed in 9% of patients. Conclusions: The rhythm and conductive disorders are common for patients with Ebstein's anomaly before and after surgery. Before surgery, more often intraventricular conduction disorders, supraventricular rhythm disorders and WPW syndrome determined paroxysmal tachycardia were observed, ventricular paroxysmal tachycardia being rare. After surgical correction, ventricular arrhythmias (premature ventricular beats, even ventricular paroxysmal tachycardia) are more common, though supraventricular rhythm and conductive disorders - "incision" paroxysmal tachycardia, atrial fibrillation and flutter, sinus node dysfunction and atrioventricular block - could persist. Due to the mentioned rhythm disorders, patients with Ebstein's anomaly should be lifelong constantly observed by the cardiologists