经食管右心声学造影在评估先兆性偏头痛患者右向左分流中的应用价值

目的 探讨经食管右心声学造影（cTEE）在检测先兆性偏头痛（MA）患者右向左分流（RLS）及鉴别其来源中的应用价值。方法 前瞻性选取我院神经内科107例MA患者（MA组）,另选45例健康志愿者（对照组）,应用cTEE观察静息状态和Valsalva动作时有无RLS及其来源,并进行半定量分级,比较两组RLS检出率及分流量。结果 MA组RLS检出率高于对照组（69.2%vs. 17.8%）,差异有统计学意义（P<0.01）,其中单纯卵圆孔未闭所致右向左分流（PFO-RLS）、单纯肺内右向左分流（P-RLS）及两者同时存在的检出率分别为10.3%、11.2%、39.3%,均高于对照组（4.4%、8.9%、4.4%）,差异均有统计学意义（均P<0.05）。两组Ⅱ级+Ⅲ级RLS检出率比较差异有统计学意义（P<0.05）。结论 cTEE在检测MA患者RLS及鉴别其来源中均有一定的应用价值。     

Detection and evaluation of intrapulmonary vascular shunt with "contrast Doppler" transesophageal echocardiography

Contrast echocardiography is useful for detecting intrapulmonary right-to-left shunt lesions. In a patient with suspected pulmonary arteriovenous fistula, contrast transesophageal echocardiography was used to demonstrate the presence of a right-to-left shunt. By use of a combination of two-dimensional echocardiography, contrast injection, and pulsed Doppler echocardiography, each pulmonary vein was successfully interrogated for evidence of contrast shunting. This case demonstrates that contrast transesophageal echocardiography is useful for the detection of intrapulmonary fistulas and that it has the potential for localization of the shunt lesion.     

Intrapulmonary arteriovenous shunt: diagnosis by saline contrast bubbles in the pulmonary veins.

A 54-year-old man with end-stage cirrhosis of the liver presented for evaluation of dyspnea. Intrapulmonary arteriovenous shunting was suspected. Transthoracic echocardiography with agitated saline contrast injection from the right antecubital vein was performed. Late arrival of saline contrast bubbles in the left atrium by pulmonary veins leading to complete left heart opacification confirmed the diagnosis of significant intrapulmonary shunting. This case and images illustrate the use of agitated saline contrast in combination with transthoracic echocardiography for the diagnosis of intrapulmonary arteriovenous fistula.     

Early appearance of echo-contrast simulating an intracardiac shunt in a patient with liver cirrhosis and intrapulmonary shunting.

Time of appearance of agitated saline contrast in the left atrium is one of the distinguishing features between intracardiac and intrapulmonary shunt. We report a patient with hepatic cirrhosis who had intrapulmonary shunting and had appearance of peripheral venous saline contrast injection in the left heart chambers within 3 cardiac cycles after its appearance in the right heart chambers despite absence of an intracardiac shunt. Thus, time of appearance of saline contrast in the left heart chambers should not be the sole criterion to distinguish intracardiac from intrapulmonary shunt.     

Recurrent transient ischemic attacks in a patient with intrapulmonary arteriovenous shunting detected after closure of a patent foramen ovale.

Paradoxical embolism through right-to-left shunts is widely accepted as a potential cause of cerebral ischemia. Contrast echocardiography is an excellent tool for detection of these shunts. The timing of the appearance of bubbles in the left atrium (ie, early vs late) allows differentiation of foramen ovale patency from intrapulmonary shunting as a result of arteriovenous malformations. We report a patient with recurrent neurologic deficit after surgical closure of a patent foramen ovale. Transesophageal echocardiography demonstrated residual right-to-left shunting from previously unrecognized pulmonary arteriovenous malformations associated with hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu). This case illustrates the fact that contrast echocardiography may fail to identify intrapulmonary shunts when a resting patent foramen ovale coexists.     

Hypoxemia secondary to right-to-left interatrial shunt through a patent foramen ovale in a patient with an elevated right hemidiaphragm

Though uncommon, right-to-left shunt through a patent foramen ovale with normal right-side pressure and with a normal interatrial pressure gradient has been reported. The speculated pathophysiology is attributed to directional blood flow streaming from the vena cava to the left atrium. Hypoxemia secondary to right-to-left shunt with normal pulmonary artery pressure has been extensively documented after right pneumonectomy. Five prior cases have documented hypoxemia secondary to a right-to-left shunt through a patent foramen ovale in the presence of an elevated right hemidiaphragm. This is the sixth documented case of right-to-left shunt through a patent foramen ovale in the presence of an elevated right hemidiaphragm with a similar presentation in which closure of the patent foramen ovale resulted in resolution of hypoxemia.     

经食管与经胸超声心动图造影检出卵圆孔未闭右向左分流效果比较

目的比较经食管超声心动图（TEE）造影和经胸超声心动图（TTE）造影对卵圆孔未闭（PFO）右向左分流（I也s）的检出效果。方法随机选取不明原因脑卒中或偏头痛伴PFO患者29例。所有患者均先、后进行了TEE和TTE造影,TTE造影探头频率为二次谐波1．7MHz／3．4MHz。TEE造影探头频率为7MHz。通过肘前静脉快速注入手振0．9％氯化钠溶液10ml进行造影,观察记录右心房充分显影后前3个心动周期内有无微泡进入左心房,根据进入左心房的微泡数量将PFO—RLS划分为4个等级：1级为无RLS,即未见微泡进入左心房;2级为少量RLS,即左心房内可见1～10个微泡／帧;3级为中量RLS,即左心房内可见11～30个微泡／帧;4级为大量RLS,即左心房内可见〉30个／帧,或左心房充满微泡。结果TTE造影和TEE造影对PFO．RLS的检出率分别为86．2％（25／29）、55．2％（16／29）。对2种方法的检出率进一步作配对,检验,结果表明差异有统计学意义（x^2=5．711,P=0．017）。TTE造影半定量分级;1级（无RLS）4例;2级（少量RLS）1例;3级（中量RLS）5例：4级（大量RLS）19例。TEE造影半定量分级：1级（无RLS）13例;2级（少量RLS）3例;3级（中量RLS）6例;4级（大量RLS）7例。对PFO—RLS半定量分级的Wllcoxon检验显示,2种技术所得结果的差异有统计学意义（Z=-3．789,P4）．000）。结论]r]匝造影对PFO—RLS的检出效率优于TEE造影。以前者替代后者不但便于相关工作的开展,还可能减少和（或）避免经食管超声检查带来的不适和并发症。     

Pseudoaneurysm with left-to-right shunt in a patient with myocardial infarction: evaluation by three-dimensional echocardiography

It is often difficult to noninvasively differentiate a post-infarction left ventricular (LV) pseudoaneurysm from a post-infarction true aneurysm. A 66-year-old woman with a past history of inferior acute myocardial infarction was admitted to our hospital because of acute decompensated heart failure. Two-dimensional transthoracic echocardiography showed an aneurysm with a narrow orifice in the inferoposterior basal area. The pulmonary to systemic flow ratio (Q _p/Q _s) was 2.2:1, which corresponded to moderate left–right shunting. Three-dimensional transesophageal echocardiography (3D-TEE) showed the orifice in the perforated right ventricular basal area with a color jet through the orifice from the LV to the right ventricle. Collectively, based on the 3D-TEE findings, we diagnosed the case as inferoposterior pseudoaneurysm with a left-to-right shunt caused by myocardial infarction.     

对比增强超声心动图对拟肝移植患者肺内分流的研究

目的探讨对比增强超声心动图(CEE)对晚期肝病肺内分流的临床诊断价值.方法采用对比超声的检查方法,对连续24例拟肝移植患者进行了前瞻性研究,筛查晚期肝病肺内右向左分流的发生率,并根据左心室微泡的显示程度半定量分析为1～3 .将CEE证实有或无肺内分流的患者分为二组,对比分析其与临床各相关因素(临床特征、肺功能检查、肝功能检查、右心室功能)的关系.结果①24例患者, 10例(41.7%)CEE证实肺内右向左分流.左心室显影异常程度1～2 (6例1 ;4例2 )出现在右心室显影后6～10余个心动周期;②两组患者在年龄、性别、动脉血气分析、肝功能化验等检查结果差异无统计学意义(P＞0.05);③两组间在上消化道出血(4/10 vs 0/14)、脾脏厚度(SP)[(65.4±13.3) mm vs (45.4±12.6) mm]对比,差异有统计学意义(P＜0.05);④两组间在肺动脉收缩压(PASP)及右室Tei指数对比差异有统计学意义[(30.2±14.7)mm Hg vs (11.5±11.8) mm Hg及(0.47±0.16 vs 0.29±0.10);P＜0.05].结论①晚期肝病合并肺内分流而无低氧血症的肺血管扩张(IPVD)比较常见,CEE对诊断IPVD提供了一种简便、敏感、非创伤性的早期检查手段;②门脉高压症是发生IPVD的主要因素;③右室Tei指数可作为评估IPVD患者右心功能的重要参数.     

Cardiac lipoma: A rare cause of right-to-left interatrial shunt with normal pulmonary artery pressure

Cardiac lipomas are rare tumors. They usually remain asymptomatic for a long time and cause angina, arrhythmia, dysfunction of the ventricles or valves, and peripheral embolization during the later stages of development. There is little or no information about right-to-left interatrial shunt with normal pulmonary artery pressure, produced as a consequence of the infiltration of the atrial septum, the right atrial wall, and the myocardium because of the presence of fat in patients with platypnea-orthodeoxia syndrome. We present a patient with this syndrome who was identified through transesophageal echocardiography. The study showed a massive right-to-left shunt without pulmonary hypertension, produced by an important cardiac infiltration of adipose tissue that created a narrow passage in the right atrium, and a redirection of the flow to a patent foramen ovale, explaining the pathophysiology of the syndrome.     

原位肝移植非静-静脉转流围术期肺氧合及肺内分流的变化

目的观察非体外静静脉转流术下原位肝移植(OLT)围术期肺氧合功能及肺内分流的改变。方法对19例晚期肝病行OLT手术的患者采用静吸复合麻醉,无肝期均未使用体外静静脉转流术。常规经右颈内静脉放置SwanGanz导管持续监测心排血量(CO),测定肺氧合功能及肺内分流率。分别在麻醉诱导后、无肝前30min、无肝30min、新肝30min和术毕抽取桡动脉血和肺动脉血进行血气分析,记录不同时期的动脉血氧分压(PaO2)、动脉血二氧化碳分压(PaCO2)和心排血指数(CI),计算肺泡动脉氧分压差(PAaO2)。根据肺内分流标准模型公式计算肺内分流率(Qs/Qt)。结果麻醉诱导后吸入氧浓度(FiO2)1.00情况下,PaO2为(385.0±56.4)mmHg(1mmHg=0.133kPa),PAaO2和Qs/Qt均明显高于正常参考值。麻醉诱导后各项指标与无肝前30min相比差异均无显著性;无肝30minCO和CI明显下降(P均<0.01),Qs/Qt明显下降(P<0.05);新肝30minPaO2、PaCO2均明显升高(P均<0.05),PAaO2明显下降(P<0.05),CO和CI均明显升高(P均<0.01);术毕CO和CI也均明显升高(P均<0.05),并维持在较高的水平,Qs/Qt明显下降(P<0.05),但PaO2、PaCO2、PAaO2则均无明显变化。结论OLT患者非静静脉转流术前和术中均存在明显的肺氧合功能障碍。     

Massive arm edema following arteriovenous dialysis shunt creation in a patient with ipsilateral permanent pacemaker

Asymptomatic subclavian vein occlusion following insertion of a permanent pacemaker (PPM) or implantable cardioverter-defibrillator (ICD) is not uncommon. We report a case of a dual-chamber PPM in a patient with an unrecognized left subclavian vein occlusion who developed massive left arm edema following ipsilateral implantation of an arteriovenous (AV) hemodialysis graft. We recommend that patients with pre-existing PPM or ICD leads who are in need of vascular access for hemodialysis should have the AV shunts placed in the contralateral arm. If this is unavoidable, then preoperative subclavian vein screening for patency should be mandatory, even in asymptomatic patients. Sonography is an appropriate initial test in such a situation.     

Saline contrast and colour Doppler transoesophageal echocardiography in detecting a patent foramen ovale and right-to-left shunts in stroke patients

Summary. A paradoxical embolism due to right-to-left shunt through a patent foramen ovale (PFO) can be responsible for stroke and other ischaemic cerebral events. We studied the usefulness of saline contrast transoesophageal echocardiography after the Valsalva manoeuvre in detecting PFO and right-to-left shunts in 28 adult patients without known reason for a recent stroke. The results were compared with conventional transthoracic colour Doppler and with transoesophageal colour Doppler techniques. A PFO was found in 24 patients (86%) of our selected study population, whereas in four patients no PFO was found. A PFO with left-to-right shunt could be diagnosed by transthoracic colour Doppler echocardiography in only one case. A PFO with left-to-right shunt was found by transoesophageal colour Doppler echocardiography in 17 patients (61%), but in only three of them was a right-to-left shunt detected, even after the Valsalva manoeuvre. In contrast, a PFO with right-to-left shunt could be detected in 21 patients (75%) by using saline contrast transoesophageal echocardiography with the Valsalva manoeuvre. However, the method was unable to detect three cases of PFO with only left-to-right shunt, which were detected by colour Doppler transoesophageal echocardiography. In conclusion, our results show that saline contrast transoesophageal echocardiography with the Valsalva manoeuvre greatly improves the echocardiographic detection of PFO with right-to-left shunts in stroke patients.     

Two-dimensional echocardiography using second harmonic imaging for the diagnosis of intracardiac right-to-left shunt: a meta-analysis of prospective studies

Right-to-left shunting (RLS), usually through a patent foramen ovale (PFO), has been associated with migraine, cryptogenic stroke and hypoxemia. With emerging observational studies and clinical trials on the subject of PFO, there is a need for accurate diagnosis of PFO in patients being considered for transcatheter closure. While transesophageal echo (TEE) bubble study is the current standard reference for diagnosing PFO, transthoracic echo with second harmonic imaging (TTE-HI) may be a preferable screening test for RLS due to its high accuracy and non-invasiveness. The aim of this meta-analysis was to determine the accuracy of TTE-HI compared to TEE as the reference. A systematic review of Medline, Cochrane and Embase was done for all the prospective studies assessing for intracardiac RLS using TTE-HI compared to TEE as the reference; both TTE-HI and TEE were performed with a contrast agent and a maneuver to provoke RLS in all studies. A total of 15 studies with 1995 patients fulfilled the inclusion criteria. The weighted mean sensitivity and specificity for TTE-HI were 91 and 93 % respectively. Likewise, the positive and negative likelihood ratios were 13.52 and 0.13 respectively. TTE-HI is a reliable, non-invasive test with proficient diagnostic accuracies. The high sensitivity and specificity of TTE-HI make it a useful initial screening test for RLS. If the precise anatomy is required, then TEE can be obtained before scheduling a patient for transcatheter PFO closure.     

Diastolic right-to-left shunting in a patient with atrial septal defect and pericardial tamponade.

We present the case of a patient with an atrial septal defect who presented with hypotension, hypoxia, and cyanosis as a result of pericardial tamponade. The classic findings of pulsus paradoxus and low measured right heart output were not present. Echocardiography demonstrated the atrial septal defect, pericardial effusion, and diastolic chamber collapse. Furthermore, Doppler study showed not only a large left-to-right shunt but also a diastolic right-to-left shunt, which explained the patient's hypoxia.