Effect of direct current shocks on left atrial mechanical function in @entity1 with structural XXXX .

@entity1 @entity64 @entity177 @entity737 @entity955 @entity299 @entity715 @entity67
OBJECTIVES: This study examined the effect of endocardial and transthoracic direct current (DC) shocks on left atrial and left @entity177 in @entity1 with structural @entity299 . BACKGROUND: DC cardioversion of @entity955 ( @entity955 ) to sinus rhythm is associated with transient left @entity955 and the development of spontaneous echo contrast (SEC). This phenomenon has been termed atrial "stunning" and may be associated with @entity715 formation and @entity64 . To what extent the shock itself contributes to atrial stunning is unclear. METHODS: Thirteen @entity1 in sinus rhythm undergoing implantation of a @entity67 ( @entity737 ) were prospectively evaluated. All @entity1 had significant structural @entity299 . To evaluate the effects of DC shocks on left atrial and left @entity177 , biphasic R wave synchronized endocardial shocks of 1, 10 and 20 J were delivered between the right ventricular electrode and the left pectoral generator of the @entity737 in sinus rhythm. R wave synchronized transthoracic shocks of 360 J were also delivered between anteriorly and posteriorly positioned chest electrodes. Transesophageal echocardiography was performed to evaluate left atrial appendage velocities, mitral inflow velocities and the presence of SEC before and immediately after each DC shock. RESULTS: There were no significant changes in left atrial or left @entity177 after endocardial or transthoracic DC shocks. Left atrial SEC did not develop after endocardial or transthoracic DC shocks. CONCLUSIONS: Endocardial and transthoracic DC shocks are not directly responsible for left atrial and left atrial appendage stunning and do not contribute to the stunning that is observed after the cardioversion of @entity955 to sinus rhythm.
