Spontaneous Echo Contrast and Atrial Fibrillation
To the Editor:
The article by Silverman and Manning1 provides a lot of important data concerning the common problem of dealing with atrial fibrillation. Yet, there is 1 point that is not considered sufficiently. What is to be done with patients who show spontaneous echo contrast in the atria in spite of sufficient long-term (at least 1 month) anticoagulation? In our experience, these patients are not rare, and at present we are quite reluctant to perform any kind of cardioversion under these conditions. We would be very pleased if the authors could comment on this relevant clinical problem.
- Copyright © 1999 by American Heart Association
Silverman DI, Manning WJ. Role of echocardiography in patients undergoing elective cardioversion of atrial fibrillation. Circulation. 1998;98:479–486.
Dr Breuer raises an important clinical issue regarding the management of patients with left atrial spontaneous echocardiographic contrast (SEC). SEC is an echocardiographic “visual” phenomenon believed to be related to blood stasis and likely reflects alterations in blood components. The incidence of SEC is not diminished by aspirin, heparin, or warfarin.R1 R2 Among patients with atrial fibrillation, SEC may be seen in almost 60% of subjects and >80% of those with atrial fibrillation and left atrial appendage thrombi.R3 R4 In the majority of patients, the “intensity” of SEC is mild, whereas a small minority of patients will have “dense” or “severe” SEC. Dense SEC is most commonly seen among patients with atrial fibrillation and coexistent mitral stenosis or markedly depressed cardiac output. In the absence of atrial thrombus, we do not consider SEC (“mild” or “severe”) as a criterion to defer early cardioversion of atrial fibrillation. For those patients with “dense” SEC, however, it may sometimes be difficult to fully exclude a thrombus. We recommend conservative therapy with 4 weeks of warfarin before cardioversion if thrombus cannot be excluded on transesophageal echocardiography (TEE). In our experience, such patients represent a very small minority of subjects (<1%) of those referred for TEE-guided early cardioversion.