Michalis L K, Thomas M R, Smyth D W, Why H J, Monaghan M J, Jewitt D E
Department of Cardiology, King's College Hospital, London, UK.
J Am Soc Echocardiogr. 1993 May-Jun;6(3 Pt 1):299-307. doi: 10.1016/s0894-7317(14)80067-9.
The incidence of spontaneous echo contrast in the left atrium, the factors with which it is associated, and its clinical significance were studied in 128 patients with native mitral valve disease or mitral valve replacement. All patients underwent both transesophageal and transthoracic echocardiography. Spontaneous echo contrast was visualized in 42 patients (33%) during transesophageal and in none during transthoracic echocardiography. Patients with spontaneous echo contrast had a significantly larger left atrial diameter (6.1 [1.1] cm vs 4.9 [0.9] cm, p < 0.001) and a greater incidence of both atrial fibrillation (54% vs 4%, p < 0.001) and left atrial thrombi (60% vs 28%, p < 0.01) compared with patients without spontaneous echo contrast. Multivariant analysis confirmed that these factors were independently associated with spontaneous echo contrast (left atrial size, p < 0.001; atrial fibrillation, p < 0.001; left atrial thrombus, p < 0.01). Patients with pure mitral regurgitation did not have any spontaneous echo contrast and anticoagulation did not influence its incidence. Spontaneous echo contrast was the only factor that was associated with a previous history of systemic embolization (history of systemic emboli in 28.6% of patients with spontaneous echo contrast vs 13.9% without spontaneous echo contrast, p < 0.05). In conclusion, spontaneous echo contrast is a common finding in the left atrium of patients with mitral valve disease or mitral valve replacement and represents a marker of increased thromboembolic risk in these patients.
对128例原发性二尖瓣疾病或二尖瓣置换术患者的左心房自发显影（SEC）发生率、相关因素及其临床意义进行了研究。所有患者均接受经食管和经胸超声心动图检查。42例患者（33%）经食管超声心动图检查时可见SEC，经胸超声心动图检查时均未发现。与无SEC的患者相比，有SEC的患者左心房直径显著更大（6.1[1.1]cm对4.9[0.9]cm，p<0.001），心房颤动（54%对4%，p<0.001）和左心房血栓形成（60%对28%，p<0.01）的发生率更高。多变量分析证实，这些因素与SEC独立相关（左心房大小，p<0.001；心房颤动，p<0.001；左心房血栓，p<0.01）。单纯二尖瓣反流患者无任何SEC，抗凝治疗不影响其发生率。SEC是与既往全身性栓塞病史相关的唯一因素（有SEC的患者中28.6%有全身性栓塞病史，无SEC的患者中为13.9%，p<0.05）。总之，SEC是二尖瓣疾病或二尖瓣置换术患者左心房常见的表现，是这些患者血栓栓塞风险增加的标志。
