Clinical and echocardiographic predictors of left atrial appendage dysfunction in patients with mitral stenosis in sinus rhythm.

BACKGROUND: Mitral stenosis (MS) causes left atrial (LA) appendage (LAA) dysfunction resulting in reduced LAA flow velocities. Low LAA peak emptying velocity (PEV), determined by transesophageal echocardiography, is a risk for thrombus formation and systemic embolism. OBJECTIVE: We sought to investigate various clinical and echocardiographic predictors of low LAA blood flow velocities. METHODS: A total of 44 patients with newly diagnosed MS were classified into two groups on the basis of the presence of high (PEV > or = 46 cm/s) or low (PEV < 46 cm/s) LAA flow profile on Doppler transesophageal echocardiography. LAA flow velocities were measured to be 27.38 +/- 8.17 cm/s in patients with LAA dysfunction and 70.75 +/- 16.71 cm/s in high-flow profile (P <.0001). Simultaneous 12-lead electrocardiogram was used to measure P waves. RESULTS: P maximum, P dispersion, and LA diameter were significantly higher in patients with low LAA PEV (n = 32) than in those with high LAA PEV (111.87 +/- 16.93 vs 96.66 +/- 14.97, P =.0084; 73.12 +/- 20.7 vs 49.16 +/- 9.96, P <.0001; 46.06 +/- 4.384 vs 38.08 +/- 7.42 mm, P =.004; respectively). Patients with MS and low LAA blood flow had smaller mitral valve area compared with those with high LAA blood flow velocity (1.48 +/- 0.431 vs 1.85 +/- 0.442 cm(2), P =.02). Male sex, spontaneous echocontrast, and thrombus were more frequent in patients with low LAA PEV [7 [21.87%] vs 5 [41.66%], P =.026; 21 [65.62%] vs 4 [33.3%], P =.088; 4 [12.5%] vs none; respectively]. Mild MS was more frequent in patients with high blood flow velocity [6 [27.2%] vs 14 [63.6%], P =.03]. CONCLUSION: At linear regression analysis, only P-wave dispersion and LA diameter predicted the LAA mechanical dysfunction reflected as low LAA PEVs.     

三维经食道超声心动图、二维经食道超声心动图、DSA测量左心耳开口与成功植入左心耳封堵器型号大小的相关性研究

目的:探讨三维经食道超声心动图成像（Three-dimensiona transesophageal echocardiography imaging,3D-TEE）、二维经食道超声心动图成像（2D-TEE）、DSA测量左心耳开口与成功植入左心耳封堵器型号大小的相关性。方法：回顾性纳入我院2019-01-03至2020-01-25非瓣膜性房颤择期行左心耳封堵术患者180例,术前分别采用2D-TEE和3D-TEE评估左心耳开口最大直径,术中进行左心耳造影测量左心耳开口最大直径。比较三种影像学方法测量的左心耳开口最大直径和最终植入的封堵器型号大小的相关性。结果：3D-TEE、2D-TEE、DSA测量左心耳开口与成功植入左心耳封堵器型号大小的相关性研究：共180例患者选入本研究,平均年龄68.25±9.15岁,男性112例（112/180,62.2%）,女性68例（68/180,37.8%）,CHA2DS2-VASc评分3.56±1.76,左房前后径46.00±6.31mm。180例患者均成功植入Watchman左心耳封堵器,最终植入的平均封堵器大小为28.1±3.2 mm。术前3D-TEE测量的左心耳开口最大直径为24.67±2.67mm,显著高于2D-TEE测量的左心耳开口最大直径（20.95±2.91mm）（P<0.001）和DSA测量的左心耳开口最大直径（23.91±2.79mm）（P <0.001）。3D-TEE测量的左心耳开口最大直径与最终植入封堵器大小呈正相关且具有极强相关性（r=0.862,P<0.001）,2D-TEE和DSA测量的左心耳开口最大直径与最终植入封堵器大小呈正相关（r=0.614,0.656,P<0.001）。结论3D-TEE通过三维容积成像测量的左心耳开口最大直径显著高于2D-TEE和DSA测量的最大径,且其与成功植入的封堵器大小的相关性最强。 关键词：三维经食道超声心动图成像　左心耳封堵术     

经食管超声评估非瓣膜性心房颤动患者左心耳血流动力学改变对左心耳血栓形成的预测价值

目的应用经食管超声心动图(TEE)评价非瓣膜性心房颤动(以下简称房颤)患者左心耳血流动力学变化状况,探讨其预测左心耳血栓形成的价值。方法选取我院房颤组138例和对照组30例,均接受TEE检查。分别从0°、45°、90°、135°不同角度观察两组左心耳二维图像,获取左心耳血流频谱及组织速度成像图像;测量左心耳射血分数(LAAEF)、最大容积(LAAVmax)、血流峰值排空速度(LAA-EV)和峰值充盈速度(LAA-FV)、血流平均排空速度(LAAAEV)和平均充盈速度(LAA-AFV),以及左心耳各壁收缩期峰值速度(LAA-SV)和舒张期峰值速度(LAA-DV)。并对两组上述指标进行比较。结果房颤组与对照组比较,LAA-EV、LAA-AEV、LAA-FV、LAA-AFV及LAAEF均减低,LAAVmax增高,差异均有统计学意义(均P0.05)。房颤组138例患者中,左心耳存在血栓者15例,无血栓者123例,对照组、房颤组无血栓者及合并血栓者LAA-AEV、LAA-AFV、LAAEF及左心耳各壁LAA-SV和LAA-DV依次减低,差异均有统计学意义(均P0.05)。LAA-AFV判断发生左心耳血栓的截断值为27.5 cm/s,特异性及敏感性分别为73.3%、96.7%;LAA-AEV判断发生左心耳血栓的截断值为33.0 cm/s,特异性及敏感性分别为80.0%、86.7%。结论 TEE能有效评价左心耳血流动力学状态及其功能。房颤患者左心耳收缩、舒张功能减低,左心耳血栓形成时减低更甚。LAA-AFV和LAA-AEV可以预测非瓣膜性房颤患者左心耳血栓形成的风险。     

基于经食管三维超声的3D打印模型评价左心耳解剖

目的 探讨经食管三维超声心动图（3D-TEE）作为左心耳（LAA）三维（3D）打印数据源的可行性及超声3D打印模型的准确性,并评价3D打印模型对特殊解剖形态LAA封堵手术的指导价值。方法 回顾性分析18例因心房颤动接受LAA封堵术的患者资料,包括LAA的3D-TEE和CT容积图像数据。对3D-TEE数据进行后处理,并使用弹性材料制作LAA的3D打印模型。采用3D打印模型评价LAA解剖分型与分叶分型,测量LAA开口的最大径、最小径及深度,并与3D-TEE及CT容积图像结果进行对比。在封堵困难的特殊形态LAA模型上进行封堵器释放试验。结果 对18例患者均成功进行超声数据后处理并获取LAA 3D打印模型。应用3D打印模型与CT容积图像对LAA进行解剖分型及分叶分型的一致性均较高,Kappa值分别为0.92和0.83。且3D打印模型对LAA开口最大径、最小径及深度的测量值与3D-TEE测量值差异均无统计学意义（P均>0.05）。18例中2例为特殊形态LAA,均通过3D打印模型进行封堵伞释放模拟出术中封堵过程。结论 基于3D-TEE的LAA 3D打印技术具有较高的可行性及准确性,有助于指导特殊形态LAA的个性化封堵。     

Highly mobile pedunculated left atrial appendage thrombus falling into the mitral valve orifice

We treated two patients with atrial fibrillation and stringlike left atrial appendage thrombus: a 66 year-old man who had apical hypertrophic cardiomyopathy and a 86 year-old woman with no underlying heart disease. In the patient with hypertrophic cardiomyopathy, transesophageal echocardiography showed a highly mobile stringlike echo protruding from the left atrial appendage and sometimes falling into the mitral orifice. Pathologic examination after excision proved the stringlike echo to be a pedunculated structure composed of red and white thrombi. Excision of thrombus was also planned for the woman, who had a history of recurrent cerebral embolism. Because her cerebral CT showed infarction with bleeding, however, surgery was postponed. The stringlike mobile thrombus was not detected by transesophageal echocardiography 1 month later, when a new embolic episode affected a foot. Clinical outcomes of these two patients differed remarkably. The critical findings by transesophageal echocardiography which facilitated differential diagnosis from cardiac tumors were: spontaneous contrast echo accompanying mural thrombuslike echo, and low flow velocity in the left atrial appendage. However, the differential diagnosis may be quite difficult in cases of tumors associated with atrial fibrillation.     

Are left atrial appendage flow velocities adequate surrogates of global left atrial function? A population-based transthoracic and transesophageal echocardiographic study.

BACKGROUND: Left atrial appendage (LAA) contraction velocities are used frequently as surrogates of global left atrial (LA) function, but the validity of this approach has not been confirmed. OBJECTIVE: The objective of our study was to assess the relationship between LAA flow velocities and multiple global LA variables. METHODS: The correlations between LAA contraction velocities and global LA variables (difference between maximal and minimal LA volumes, mitral inflow A velocity, atrial ejection force, mitral annulus late diastolic [a'] velocity, pulmonary vein atrial reversal velocity) were assessed in 349 subjects participating in the Stroke Prevention: Assessment of Risk in a Community study (age, 67 +/- 11 years; 53% men; all subjects in sinus rhythm), who were examined with transthoracic and transesophageal echocardiography. RESULTS: The correlations between LAA contraction velocities and multiple global LA variables were poor or nonsignificant. The best correlations, albeit weak, were between LAA velocities and mitral annulus a' velocities (r = 0.32 and r = 0.35 for correlations with septal and lateral annulus a' velocities, respectively, P <.001). Low LAA contraction velocities (lowest 10%, velocities <56 cm/s) were not sensitive in detecting low values (lowest 10%) of LA variables (sensitivity <0.2 for most LA variables). In a subgroup of subjects with lower left ventricular ejection fraction (< or =50%), the correlations between LAA velocities and LA variables were not apparently better than those in the total population. LAA velocities correlated negatively with LAA orifice diameter (r = -0.29, P =.002). The correlations between LAA velocities and global LA variables remained poor after correcting for LAA orifice size. CONCLUSION: LAA contraction velocities correlate poorly with multiple LA variables. Therefore, LAA flow velocities should not be used as surrogates of global LA function.     

A case of coronary artery fistula with mitral stenosis

Coronary artery fistulae, being a rare form of congenital anomalies of the coronary arteries, are usually discovered by chance during coronary arteriography. However, these fistulae can cause an important coronary morbidity and mortality leading to angina, syncope, congestive heart failure, myocardial infarction and sudden death. The coincidence of mitral stenosis and congenital artery fistula is rare in the literature. In our case report, a patient with a coronary artery fistula originating from the circumflex, draining to the main pulmonary artery, discovered at cardiac catheterization and coronary angiography done with a prediagnosis of mitral stenosis is presented in the light of the literature.     

Right and left atrial appendage function in patients with mitral stenosis and sinus rhythm

Tissue Doppler imaging (TDI) is generally used for the assessment of ventricular function, and to a lesser extent, to evaluate the left atrial appendage (LAA). In the present study, we used TDI to analyze the contractile function of the right atrial appendage (RAA). The aim of this study was a comprehensive evaluation of RAA and LAA contractile function in patients with mitral stenosis and sinus rhythm. A total of 69 patients were assessed: group 1 (23 patients with severe MS, 38 ± 11 years, 20 women), group 2 (23 patients with mild MS, 39 ± 12 years, 19 women) and group 3 (23 healthy subjects, 42 ± 14 years, 16 women). Multiplane transesophageal echo was performed in all patients. The RAA was visualized at 130° and the LAA at 0°. TDI sample volume was placed in the tip of both atrial appendages, with an ultrasound beam angle < 10°. Flow velocities and myocardial velocities were measured. The presence of thrombus and/or spontaneous echo contrast (SEC) was assessed. TDI showed in normal subjects, myocardial contraction velocities in RAA similar to that of the LAA (21.8 ± 4.2  vs. 20.1 ± 4 cm/s, respectively, P = NS). In patients with MS, myocardial velocities in both atrial appendages were significantly lower than in normal subjects (RAA: 17.4 ± 5.1 vs. 21.8 ± 4.2 cm/s, respectively, P < 0.01, LAA: 9 ± 5.1 vs. 20.1 ± 4 cm/s, respectively, P < 0.001). Linear regression analysis showed a correlation between the impairment of systolic function of both appendages, pulmonary arterial pressure, valve area and transmitral gradient. Of the 46 patients with MS, patients with intense SEC had lower flow and myocardial velocities in the LAA than patients without SEC (16 ± 5 vs. 50 ± 3 cm/s, 6 ± 2 vs. 10.6 ± 5.6 cm/s, respectively, P < 0.001 and P < 0.001). In healthy subjects, myocardial contraction velocities in both appendages were similar. Patients with MS and sinus rhythm had contractile dysfunction of both appendages, shown by the decrease in myocardial velocities and related to the increase in atrial afterload. Both appendages exhibited a relation between contractile dysfunction and the presence of SEC, but dysfunction was less marked in the RAA, which might explain the lower prevalence of thrombi in the RAA. Tomás F. Cianciulli and María C. Saccheri are researchers of the Secretary of Health of the Government of the City of Buenos Aires.     

Spontaneous left atrial echocardiographic contrast in mitral stenosis: early disappearance after valve replacement.

We describe a patient with mitral stenosis and severely enlarged left atrium. Transthoracic echocardiography showed a false image of intraatrial thrombus, whereas transesophageal echocardiography showed massive spontaneous left atrial contrast. Intraoperative transesophageal echocardiography was performed. During cardioplegic arrest the contrast was enhanced, but it gradually and completely cleared 15 minutes after cardiopulmonary by-pass arrest. Transesophageal echocardiography is a useful technique for the study of intraatrial masses and may bring a new dimension to tissue characterization studies.     

Measurement of left atrial appendage size by transesophageal echocardiography

Transesophageal echocardiography (TEE) is the most common imaging method for evaluating left atrial morphology. Recent advances in 64-slice multidetector computed tomography (64-MDCT) allow accurate measurement of left atrial appendage (LAA) volume. The aim of this study was to evaluate the accuracy of LAA sizing by TEE in comparison with 64-MDCT in patients with atrial fibrillation. Electrocardiogram-gated 64-MDCT and TEE were performed within 2 days in 18 consecutive patients (63 ± 9 years old, 12 males, 5 paroxysmal atrial fibrillation) with nonvalvular atrial fibrillation. LAA area and LAA volume were measured at end-systole by TEE and 64-MDCT, respectively. The largest LAA area was measured on TEE image. Five patients were in sinus rhythm during examinations. In all patients, LAA was clearly visualized; the largest area of LAA was 9.3 ± 3.9 mm² and the LAA volume was 21.6 ± 7.5 ml. A significant correlation between LAA area and LAA volume was observed (p = 0.0003, r = 0.75). TEE allows a detailed evaluation of the LAA structure by two-dimensional imaging. LAA size could be evaluated by TEE despite its morphological complexity, i.e., sac-like or multilobed structure.     

经食管超声心动图在左心耳封堵术中的应用进展

心房颤动（房颤）是临床最常见心率失常之一,欧美研究资料显示房颤的患病率为0.4%~1.0%[1-2],我国房颤总患病率约为0.77%,标准化率约为0.61%,年龄分组显示患病率随年龄增加而显著增高,且男性房颤患病率高于女性[3-4]。房颤的严重并发症之一为血栓,目前预防房颤血栓需终身服用抗凝药物,但部分患者出血风险高,药物依从性差,因而其应用受到一定程度限制[5]。非瓣膜疾病房颤患者脑卒中>90%心源性栓子来源于左心耳（left atrail appendage,LAA）[6],左心耳封堵为此类患者提供了一种新的选择。本文主要介绍经食管超声心动图（transesophageal echocardiography,TEE）在LAA封堵术前、术中的应用进展。     

Time interval determination from left atrial appendage ejection flow in patients with mitral stenosis

The feasibility of determining the time interval from left atrial appendage (LAA) flow was examined using transesophageal Doppler echocardiography. Time intervals were compared between LAA flow and mitral flow patterns during late diastole in 8 patients with mitral stenosis and in 12 controls. The start of ejection flow from the LAA was later than the initiation of mitral flow, but the termination was same in both flows, indicating the contribution of LAA ejection to the latter half of the left atrial booster pump function. The pre-ejection time and the time interval from P-wave to end-ejection correlated significantly with left atrial dimensions (r = 0.55, and r = 0.70, respectively). The pre-ejection time, duration of the ejection flow from the LAA, and duration of mitral flow in the atrial contraction phase were significantly longer in patients with mitral stenosis (126 ± 14 msec, 131 ± 36 msec, and 167 ± 28 msec, respectively) than in the controls (109 ± 13 msec, 108 ± 15 msec, and 141 ± 17 msec, respectively). These results indicate that electrical conduction time from the right atrium to LAA can be estimated from the LAA ejection flow, and the time is related to the left atrial size. In patients with mitral stenosis, LAA contraction may contribute to left ventricular filling in the latter half of the atrial contraction phase. © 1997 John Wiley & Sons, Inc. J Clin Ultrasound 25 : 97–102, 1997.     

经食管超声心动图在左心耳封堵术中的应用价值研究

目的探讨经食管超声心动图（TEE）在经皮左心耳封堵术前筛选、术中监测及术后随访中的应用价值。 方法选取2016年1月至2016年12月武汉亚洲心脏病医院共54例心房颤动患者应用Watchman封堵器行经皮左心耳封堵术,依据封堵术后是否出现残余分流分为残余分流组与无残余分流组。术前所有患者均行经胸超声心动图（TTE）和TEE检查,排除瓣膜器质性病变及左心耳血栓者。术前TEE测量入选患者的左心耳最大开口径及最大深度;术中TEE引导房间隔穿刺、联合X线血管造影选择封堵器型号,引导封堵传输系统的定位及指导封堵器释放,并评估术中安全性;术后即刻及45 d进行随访超声检查。残余分流组与无残余分流组的最大压缩比及最小压缩比均值比较采用t检验;TEE所测左心耳最大开口径与术中X线造影及最终所选封堵器大小的相关性分析采用Pearson法。 结果54例行左心耳封堵术的患者,均封堵成功,压缩比均在8%~20%之间,残余分流组与无残余分流组组间最大压缩比及最小压缩比均值比较［（17.70±2.28）% vs（17.10±2.42）%,（12.40±2.82）% vs（12.60±2.68）%］,差异均无统计学意义（P均>0.05）;87%（47/54）的患者左心耳开口径与深度最大值在TEE 135°上获得;TEE 135°上所测LAA开口径与TEE 4个角度上所测最大开口径,TEE测量LAA最大开口径与造影测量LAA开口径,TEE 135°所测LAA开口径与所选封堵器型号,相关性均较好（r=0.919、0.622、0.602,P均<0.001）,相关方程分别为：Y=1.01X＋1.11、Y=0.68X＋6.56、Y=0.80X＋1.24;所有随访患者均未出现脑血管或其他血管栓塞事件,术中出现少量心包腔积液3例,术后7 d复查均未见心包腔积液,2例术后45 d复查封堵器表面出现血栓。 结论TEE在左心耳封堵术前对患者的筛选、术中引导房间隔穿刺、封堵器型号的选择、指导释放过程及即刻评估封堵效果、术后随访中有重要的应用价值,TEE 135°扫查较其他角度检测出残余分流更敏感。     

经胸实时三维超声和经食管超声心动图对左心耳血栓诊断的对比研究

目的　探讨实时三维经胸超声心动图(Live3DTTE)技术对于左心耳血栓(LAAT)的诊断价值。方法　选择26例左心耳血栓患者,平均年龄( 61±7 )岁,均于经食管超声心动图(TEE)检查前接受Live3DTTE检查。采取双盲原则进行结果判断。以TEE诊断结果作为标准,评价Live3DTTE对于LAAT的诊断价值。结果　Live3DTTE的诊断敏感性为73%,特异性为60%,准确性为65%,阳性预测值为57%,阴性预测值为75%。观察者间判断一致性良好(Kappa=0. 468,P<0. 05)。观察者自身判断结果高度一致(Kappa=0. 769,P<0. 0001)。结论　Live3DTTE是无创、痛苦小且重复性较好的LAAT诊断手段,在与TEE的初步比较中显示了其较高的敏感性和阴性预测值。     

左心耳三维超声心动图研究进展

左心耳特殊的解剖结构、功能特点使其成为目前研究的热点.本文针对实时三维超声心动图在左心耳实时三维成像可行性的研究、形态的观察、开口面积及深度的测量、体积及功能的研究、血栓的诊断以及左心耳闭塞术中的应用进行综述.     

Stenotic mitral valve prosthesis with left atrial thrombus.

We report the CMR findings of a patient with stenotic biological mitral valve prosthesis that was complicated by thrombus formation in the left atrium. The case illustrates the ability of CMR to assess biological prosthetic valves and to provide a comprehensive diagnostic approach in this clinical scenario.     

Correlation between quantitative left atrial spontaneous echocardiographic contrast and intact fibrinogen levels in mitral stenosis.

An association between left atrial spontaneous echocardiographic contrast (LASEC) and thromboembolic events has been recognized. However, the appearance of LASEC and the assessment of its intensity are gain dependent. To evaluate the relation between LASEC intensity and coagulation activity, 11 patients with mitral stenosis underwent transesophageal echocardiography with quantitative integrated backscatter assessment of LASEC. Right and left atrial blood samples were evaluated for concentrations of coagulation markers, including intact fibrinogen, fibrinopeptide A, D-dimer, prothrombin fragment 1+2, and thrombin-antithrombin III complex. The patients were found to have significantly higher mean left atrial concentrations compared with right atrial concentrations of thrombin-antithrombin III (28.46 +/- 21.05 versus 3.21 +/- 7.16 ng/mL, respectively; P =.001) and fibrinopeptide A (32.78 +/- 17.54 versus 7.42 +/- 8.27 nmol/L, respectively; P <.001). Intact fibrinogen levels were similar in both atria, and a strong, direct correlation existed between left and right atrial intact fibrinogen levels (r = 0.78, P =.005). Quantitative integrated backscatter of LASEC correlated directly with left atrial fibrinogen level (r = 0.78, P =.013) but not with markers of thrombin generation (thrombin-antithrombin III) or activity (fibrinopeptide A). Our results confirm that patients with mitral stenosis have evidence of a regional hypercoagulable state in the left atrium. However, the intensity of LASEC assessed by quantitative integrated backscatter correlates with both right and left atrial intact fibrinogen level, a systemic marker of coagulation.     

Embolization of a left atrial ball thrombus during transesophageal echocardiography.

We report a case of systemic embolization of a left atrial ball thrombus during transesophageal echocardiography (TEE). A 49-year-old man with rheumatic mitral stenosis and atrial fibrillation underwent TEE to evaluate a transient cerebral ischemic attack. TEE demonstrated a free-floating left atrial thrombus. Disappearance of the thrombus during the study occurred after tachycardia and was associated with acute hemiplegic stroke and an absent radial pulse. The possible mechanism of embolization and the implications for the selection and management of patients undergoing TEE are discussed.