Study of left atrial appendage flow spectra in precardioversion and postcardioversion by TEE in nonrheumatic atrial fibrillation

Objective To evaluate the flow spectra and the hemodynamic characteristics of left atrial appendage(LAA) of patients with nonrheumatic atrial fibrillation(NRAF) in precardioversion and postcardioversion.Methods LAA flow spectra examinations were preformed by TEE in 60 patients with NRAF before cardioversion and after cardioversion.Results Three different flow spectra were observed.①Irregular but well defined LAA emptying and filling Doppler signals were recorded within each cardiac cycle; ②Very low flow signals were recorded and sometimes,no signals at all could be detected; ③Prolonged low velocity wave was recorded.In the process of changing from the first pattern to the third pattern,left atrial and left atrial appendage were enlarged,left atrial function and left atrial appendage function were decreased,spontaneous echocardiographic contrast(SEC) and thromboembolism event were increased.LAA flow spectra converted to a organized contraction and diastole patterns after successful cardioversion,left atrial appendage peak emptying velocity(LAA PEV) [(23±10)cm/s] was lower than that before cardioversion [(30±12)cm/s](P 0.001 ).SEC could be generated in 8 patients,intensified in 11 patients.Conclusions LAA flow spectra can reflect left atrial function, LAA function and left ventricular diastolic function.LAA flow spectrum after successful cardioversion converted to a sinus rhythm pattern,LAA function developed stunning