Giant Left Atrial Thrombus Without Mitral Valve Disease
C Özbek, U Yetkin, O Gökalp, A ?ahin, ? Yürekli, A Gürbüz
Keywords
atrial fibrillation, left atrial thrombus, surgical treatment
Citation
C Özbek, U Yetkin, O Gökalp, A ?ahin, ? Yürekli, A Gürbüz. Giant Left Atrial Thrombus Without Mitral Valve Disease. The Internet Journal of Thoracic and Cardiovascular Surgery. 2007 Volume 11 Number 2.
Abstract
Large left atrial mural thrombi in the absence of mitral valve stenosis has been reported rarely in the literature.It's usually observed with mitral valve disease. This mass has risks of sudden circulatory collapse and systemic embolization.
In this study we report a patient whith a very large and fresh thrombus in the left atrium without mitral valve stenosis and our successful surgical removal therapy.
Our case indicates that emergent surgical removal of the large left atrial mural thrombus should be done immediately after the diagnosis and we consider this approach for the best treatment at the time.
Introduction
The discovery of a large left atrial (LA) mass obliges the clinician to perform a differential diagnosis including tumour versus thrombus, but because of morphology and mobility of the mass, it is always difficult to differentiate one from the other(1). Most of LA thrombus were complicated with mitral stenosis, LA thrombus without mitral disease is rare(2). Regardless of mechanism, the diagnosis of a left atrial thrombus ball should be regarded as an urgent indication for preventive surgery(3).
Case Presentation
A 55-year-old man presented with complaint of mild dyspnea at rest.He experienced neither embolism nor syncope.At the time of hospitalization,he was in New York Heart Association functional class II-III and ECG showed atrial fibrillation rythym.Bidimensional transthoracic echocardiography revealed normal left ventricular dimension and function (ejection fraction was 60%) and left atrial dilatation. Transthoracic color-flow Doppler echocardiography revealed an echogenic large(giant) left atrial mass diagnosed as a fresh left atrial mural thrombus in the dilated left atrium with the diameters of 5.3x4.2cm(Figure 1). There was an attachment of the thrombus to the atrial wall.It was compact,homogeneous and stationary. Transesophageal echocardiography shoowed similar findings.
Figure 1
Furthermore, moderate mitral and tricuspid regurgitations were found. Computed tomography (CT) revealed left atrial mural thrombus in the dilated left atrium(Figure2).
Figure 2
Coronary angiography showed normal coronary arteries.
An urgent operation was performed. After cardiopulmonary bypass the aorta was cross-clamped. Our standard radiofrequency ablation technique was performed with Cardioblate BP (bipolar) Surgical Ablation Device (Medtronic 60821) .Cross clamp duration extended 5 minutes with this accompanying procedure.The left atrium was opened longitudinally. The mitral valve was morphologically normal in appearance with no detectable valve dysfunction. Under the extracorporeal circulation, the ball thrombus, 45 X 60 mm in size,was removed (Figure 3).
Figure 3
Its cut surfaces showed a laminated structure.On pathologic examination the mass was diagnosed as an organized thrombus. Postoperative rhythm was sinusal.He did not require inotropic support during weaning from cardiopulmonary bypass and early postoperative period. The postoperative course was uneventful. The functional capacity of our patient improved dramatically and he was in NYHA functional class I-II. He was followed at our outpatient clinic without additional problem.
Discussion
Left atrial ball-shaped masses may be thrombi, vegetations or tumor. Treatment may be different in each of these entities, and includes antibiotics, anticoagulants or surgery (4,5).
Left atrial ball thrombus in the absence of mitral valve disease has been reported even less frequently with most of the patients having been described as not being adequately anticoagulated for their atrial fibrillation(3,6).
Although it may not be possible to know the precise mechanism by which the thrombus ball was formed, it is reasonable to assume an origin from a smaller mural thrombus created secondary to chronic blood stagnation(3).It gradually enlarges and forms projecting mass that remains attached to the atrial wall by a pedicle(7).During thrombus development and subsequent morphologic changes,it is very likely that the patient may experience transient embolisms or strokes(7,8).
Transthoracic and transesophageal echocardiography are the procedures of choice for the diagnosis of cardiac mass involving left atrium (4,9).
When this is present, its importance can not be undermined as it has the potential to be fatal secondary to acute mitral valve orifice occlusion (3) Distal embolization subsequent to fragmentation is believed to be the cause of cerebrovascular accident or potential loss of a limb(3,10). Because of the high risk of sudden death with strangulated ball thrombus and systemic embolization, surgical removal of the ball thrombus should be done immediately after the diagnosis was established(11).
In conclusion;for the large left atrial mural thrombus, emergency surgery was considered the best treatment option at the time(3).Surgery produces a long term survival rate of more than 90%(12).
Correspondence to
Doç. Dr. Cengiz ÖZBEK ?air E?ref Bulvari,No:66/1,Idil Apt. 35220, Alsancak / IZMIR / TURKEY Tel: +90 532 2870780 e-mail: cengizozbek@superonline.com & ufuk_yetkin@yahoo.fr