Chimowitz M I, DeGeorgia M A, Poole R M, Hepner A, Armstrong W M
Department of Neurology, University of Michigan Medical Center, Ann Arbor 48109.
Stroke. 1993 Jul;24(7):1015-9. doi: 10.1161/01.str.24.7.1015.
Spontaneous echo contrast is a dynamic smokelike signal that is detected by transesophageal echocardiography in patients with stasis of blood in the left atrium. We designed this study to determine if spontaneous echo contrast is associated with an increased risk of previous stroke or peripheral embolism.
Forty-two patients with spontaneous echo contrast were identified (34 had atrial fibrillation or mitral stenosis; 8 had neither). Control subjects comprised 40 patients randomly selected from patients with atrial fibrillation or mitral stenosis who did not have spontaneous echo contrast at transesophageal echocardiography. The frequency of vascular risk factors, echocardiographic features, and stroke or peripheral embolism within 1 year of echocardiography were compared in the two groups.
The frequency of traditional risk factors for stroke were the same in both groups, yet 9 of 42 patients with spontaneous contrast had stroke or peripheral embolism compared with only 1 of 40 control subjects (P < .02; relative risk, 10.6; 95% confidence interval, 1.3 to 88.4). In patients with nonvalvular atrial fibrillation, 6 of 12 patients with spontaneous contrast had a stroke or peripheral embolism compared with 1 of 28 patients without spontaneous contrast (P < .001; relative risk, 27.0; 95% confidence interval, 2.7 to 267.8).
Spontaneous echo contrast is highly associated with previous stroke or peripheral embolism in patients with atrial fibrillation or mitral stenosis. Transesophageal echocardiography may enable stratification of cardioembolic risk in patients with nonvalvular atrial fibrillation.
自发显影是经食管超声心动图在左心房血液淤滞患者中检测到的一种动态烟雾状信号。我们开展这项研究以确定自发显影是否与既往中风或外周栓塞风险增加相关。
确定了42例有自发显影的患者（34例有房颤或二尖瓣狭窄；8例两者均无）。对照组包括40例从房颤或二尖瓣狭窄患者中随机选取的、经食管超声心动图检查无自发显影的患者。比较两组血管危险因素的频率、超声心动图特征以及超声心动图检查后1年内中风或外周栓塞的发生率。
两组中风的传统危险因素频率相同，但42例有自发显影的患者中有9例发生中风或外周栓塞，而40例对照组患者中仅有1例发生（P <.02；相对危险度，10.6；95%置信区间，1.3至88.4）。在非瓣膜性房颤患者中，12例有自发显影的患者中有6例发生中风或外周栓塞，而28例无自发显影的患者中有1例发生（P <.001；相对危险度，27.0；95%置信区间，2.7至267.8）。
自发显影与房颤或二尖瓣狭窄患者既往中风或外周栓塞高度相关。经食管超声心动图可能有助于对非瓣膜性房颤患者的心源性栓塞风险进行分层。
