Penetrating atherosclerotic aortic ulcer: documentation by transesophageal echocardiography

Objectives. This study sought to describe the ability of transesophageal echocardiography (TEE) to document the presence of penetrating atherosclerotic aortic ulcers and their complications.Background. TEE has greatly enhanced our ability to assess patients with suspected aortic disease. However, the utility of this technique in the diagnosis of penetrating atherosclerotic aortic ulcers is still undefined.Methods. TEE was performed prospectively in 194 patients to evaluate aortic disease. Twelve patients with the diagnosis of aortic ulcers or their complications were specifically studied. The diagnosis was confirmed by pathologic studies in six patients and by an additional diagnostic technique (angiography, computed tomography or magnetic resonance imaging) in the other six. All 12 patients were hypertensive and presented with chest or back pain; the mean age was 65 years (range 56 to 79). The initial working diagnosis was acute aortic dissection in nine patients. Aortic ulcers were located in the descending thoracic aorta in eight patients, the aortic arch in two and the ascending aorta in two.Results. TEE could detect aortic ulcers or their complications in 10 patients but failed to detect these lesions in the remaining 2 (1 with aortic ulcers in the distal ascending aorta and 1 with aortic ulcers in the aortic arch). In four patients, aortic ulcers were detected as a calcified focal outpouching of the aortic wall and were associated with concomitant aneurysmal dilation of the aorta in two patients and with a small localized intramural hematoma in one. TEE visualized a partially thrombosed pseudoaneurysm complicating an aortic ulcer in the descending thoracic aorta of two patients. Four patients had an aortic ulcer complicated by a “limited aortic dissection” in the descending aorta that could be detected by TEE. Five patients underwent operation, two because of aneurysmal dilation of the aorta and three because of aortic dissection; two patients died of aortic rupture; the remaining five did well (11-month follow-up) without operation.Conclusions. Aortic ulcers should be included in the differential diagnosis of chest or back pain, especially in elderly hypertensive patients. These ulcers and their complications may be recognized by TEE.     

Detection of dissection of the thoracic aorta: improved specificity by magnetic resonance tomography in comparison with echocardiography techniques]

The purpose of this study was to assess the reliability of conventional transthoracic and transoesophageal two-dimensional echocardiography combined with color-coded Doppler flow imaging (TEE) and ECG-triggered magnetic resonance imaging (MRI) for the diagnosis of thoracic aortic dissection and associated epiphenomena. A total of 53 patients with clinically suspected aortic dissection were subjected to a transthoracic and transoesophageal ultrasound examination and magnetic resonance imaging; the results of each imaging modality were compared and validated against the morphological standards of contrast angiography (n = 53) and/or intraoperative findings (n = 27) or autopsy (n = 7). In this series no deleterious events were encountered with either non-invasive imaging method. In contrast to conventional echocardiography the sensitivities of both MRI and TEE were 100% for detecting a dissection of the thoracic aorta, irrespective of its location. However, the specificity of TEE was lower than the specificity of MRI for a dissection (TEE 68.2% versus MRI 100%; p less than 0.005), which resulted from false positive TEE findings mainly confined to the ascending segment of the aorta (specificity of TEE 78.8% versus 100% by MRI; p less than 0.01). In addition, MRI proved to be more sensitive than TEE in detecting the formation of thrombus in the false lumen of both the aortic arch (p less than 0.01) and the descending segment of the aorta (p less than 0.05). There were no discrepancies between the two imaging techniques in detecting the site of entry to a dissection, aortic regurgitation or pericardial effusion. Both MRI and TEE are atraumatic, safe, and highly sensitive methods to identify and classify acute and subacute dissections of the entire thoracic aorta. However, TEE is associated with lower specificity for lesions in the ascending aorta. These results may still favor TEE after a precursory screening transthoracic echogram in suspected aortic dissection, but will establish MRI as an excellent method to avoid false positive findings. Anatomical mapping by MRI may emerge as a promising comprehensive approach and, eventually, as a morphological standard to guide surgical interventions.     

Diagnosis of thoracic aortic dissection. Magnetic resonance imaging versus transesophageal echocardiography.

BACKGROUND. Aortic dissection requires prompt and reliable diagnosis to reduce the high mortality. The purpose of this study was to assess the reliability of both ECG-triggered magnetic resonance imaging (MRI) and transesophageal two-dimensional echocardiography combined with color-coded Doppler flow imaging (TEE) for the diagnosis of thoracic aortic dissection and associated epiphenomena. METHODS AND RESULTS. Fifty-three consecutive patients with clinically suspected aortic dissection were subjected to a dual noninvasive imaging protocol in random order; imaging results were compared and validated against the independent morphological "gold standard" of intraoperative findings (n = 27), necropsy (n = 7), and/or contrast angiography (n = 53). No serious side effects were encountered with either imaging method. In contrast to a precursory screening transthoracic echogram, the sensitivities of both MRI and TEE were 100% for detecting a dissection of the thoracic aorta irrespective of its location. The specificity of TEE, however, was lower than the specificity of MRI for a dissection (TEE, 68.2% versus MRI, 100%; p less than 0.005), which resulted mainly from false-positive TEE findings confined to the ascending segment of the aorta (TEE, 78.8% versus MRI, 100%; p less than 0.01). In addition, MRI proved to be more sensitive than TEE in detecting the formation of thrombus in the false lumen of both the aortic arch (p less than 0.01) and the descending segment of the aorta (p less than 0.05). There were no discrepancies between the two imaging techniques in detecting the site of entry to a dissection, aortic regurgitation, or pericardial effusion. CONCLUSIONS. Both MRI and TEE are atraumatic, safe, and highly sensitive methods to identify and classify acute and subacute dissections of the entire thoracic aorta. TEE, however, is associated with lower specificity for lesions in the ascending aorta. These results may still favor TEE as a semi-invasive diagnostic procedure after a precursory screening transthoracic echogram in suspected aortic dissection, but they establish MRI as an excellent method to avoid false-positive findings. Anatomic mapping by MRI may emerge as the most comprehensive approach and morphological standard to guide surgical interventions.     

Rapid progression of discrete type A intramural hematoma: prevention of a "procedure-related" complication by intraoperative transesophageal echocardiography.

PURPOSE: To report a case illustrating the utility of transesophageal echocardiography (TEE) before planned stent-graft placement for chronic type B aortic dissection. CASE REPORT: A 64-year-old man with acute aortic syndrome and an 8-year-old interposition graft in the distal aortic arch for acute type B dissection was referred for dissection of the descending thoracic aorta down to the aortic bifurcation; the false lumen was dilated to 65 mm and was partially thrombosed. The ascending aorta showed discrete, eccentric, 4-mm wall thickening that was not considered clinically significant. Stent-graft closure of the entry tear in the proximal descending thoracic aorta was elected. However, as the endovascular procedure was about to commence, TEE showed striking eccentric thickening of the aortic wall of up to 18 mm. The endovascular procedure was stopped, as it was decided to urgently replace the ascending aorta. The next day, the patient underwent successful ascending aortic replacement and simultaneous antegrade stent-graft implantation over the descending thoracic aortic entry tear via the open aortic arch. The postoperative course was uncomplicated, and the patient was discharged 19 days after surgery. He remains well at 6 months after the procedure. CONCLUSIONS: Our case demonstrates that dissection of the ascending aorta may occur not only due to endograft-induced intimal injury, but may also occur due to underlying but undiagnosed or underestimated disease of the ascending aorta or arch. Besides procedural guidance, intraoperative TEE is a useful tool to detect such disease to avoid subsequent "procedure-related" complications.     

Aortic ectasia with hemiazygos vein dilatation: a mimicker of aortic dissection

Infrahepatic interruption of the inferior vena cava (IVC) is a rare but well-documented finding. In this condition, the IVC between renal and hepatic vein is absent and the hepatic veins directly empty into the right atrium; because of the enlargement of the azygos-hemiazygos vein system, this condition could mimic aortic pathology. We will describe a case of aortic arch enlargement with dilatation of hemiazygos vein, which was initially misdiagnosed by two-dimensional transesophageal echocardiography (TEE) as aortic dissection. TEE-Doppler identified the real condition, which was confirmed by computed tomography.     

Rapid diagnosis and management of thoracic aortic dissection and intramural haematoma: a prospective study of advantages of multiplane vs. biplane transoesophageal echocardiography.

AIMS: The purposes of this study were to compare the accuracy of multiplane vs. biplane transoesophageal echocardiography (TEE) in the diagnosis of aortic dissection and aortic intramural haematoma, and to test whether these techniques provide all the diagnostic information required to make management decisions. METHODS AND RESULTS: Fifty-eight consecutive patients with clinically suspected aortic dissection were studied with multiplane TEE; all cases who required surgery underwent intraoperative monitoring with multiplane TEE. The following multiplane TEE data were analysed: the angle between current and 0 degrees plane at which each view was obtained; the success rate in the evaluation of true and false lumen, entry tear, coronary artery involvement, aortic regurgitation, pericardial effusion. Advantages of multiplane over biplane TEE have been evaluated by the demonstration of usefulness of views obtained in planes other than 0 degrees-20 degrees or 70 degrees-110 degrees, assuming that with manipulation of a biplane probe a 20 degrees arc could be added to the conventional horizontal and vertical planes. On the basis of TEE findings, aortic dissection was confirmed in 36 cases (18 type A, 12 type B, six intramural haematoma). The specificity and sensitivity of TEE in terms of the presence or absence of aortic dissection or intramural haematoma were 100%. An additional clinical value of multiplane over biplane TEE in the evaluation of ascending aorta, aortic arch, entry tears and coronary artery involvement was demonstrated. All cases with type A aortic dissection or intramural haematoma involving the ascending aorta had an operation that was performed immediately after the diagnosis (hospital mortality, 13%). Patients with type B aortic dissection were treated medically; 25% of these cases were operated later (hospital mortality, 0%). CONCLUSIONS: Multiplane and biplane TEE have excellent and similar accuracies in the evaluation of aortic dissection and intramural haematoma. Multiplane TEE improves the visualization of coronary arteries, aortic arch and entry tears; it appears to be an ideal method as the sole diagnostic approach before surgery in type A aortic dissection.     

Emergency surgical management of acute aortic dissection: role of transesophageal echocardiography.

The accuracy of transesophageal echocardiography in the diagnosis and surgical management of acute aortic dissection was determined in 54 patients who underwent surgery for acute aortic dissection. Results of the investigations were compared to the surgical assessment. From April 1993 to November 1997, we operated 54 patients (44 male and 10 female) for acute aortic dissection. Mean age was 60 +/- 9 years. At surgery, a De Bakey type I aortic dissection was diagnosed in 30 patients, type II in 23 and type III retrograde in 1. Operating procedures were: replacement of ascending aorta (24 cases), replacement of ascending aorta and aortic arch (17 cases), replacement of ascending aorta and aortic valve replacement (2 cases), Bentall procedure (6 cases) and end-to-end anastomosis of the ascending aorta (4 cases). Initial diagnosis, performed in emergency wards, was done on a clinical basis in 6 patients, on CT scan in 19, on transthoracic echocardiography in 14, and on TEE basis in 12. Three patients underwent angiography before our evaluation. As per our protocol, all patients underwent confirmation of the diagnosis by TEE. Seven patients needed additional instrumental investigations, 2 with CT scan and 5 with angiography. TEE confirmed the diagnosis of aortic dissection in all cases but one. Moreover, it described the site of the intimal tear, the extension of the dissecting process and accessory findings, such as pericardial effusion, aortic incompetence and left ventricular function. The interval between patient presentation and skin incision was a maximum of 70 minutes. At surgery, diagnosis of De Bakey classification was confirmed in 98% of cases; in 90.7% of cases exact location of the entry site was confirmed. In one case, an entry site in the arch diagnosed by TEE but not recognized at surgery, was observed at necropsy. Intraoperatively, we routinely used TEE to monitor retrograde systemic perfusion and correct implant of the vascular prosthesis. One case of malperfusion of the thoracic aorta through the false lumen was observed and managed. In one case we diagnosed acute obstruction of the prosthesis by bleeding in the wrapped aorta, which required reoperation. Assessment of ventricular function was obtained in all patients: in two cases, observation of low right ventricular function led us to perform aortocoronary by-pass to the right coronary artery. In conclusion, the high level of correspondence between TEE diagnosis and surgical anatomy prompted us to perform transesophageal echocardiography as the primary and often sole diagnostic procedure in acute aortic dissection. TEE, in experienced hands, has proven to be a highly reliable, safe and low-cost diagnostic tool. It can be performed at the patient's bedside within just a few minutes of the suspected diagnosis, thereby lowering the mortality rate of the natural history. Again, it can also be used in the operating theatre as an "on-line examination" as well as for assessment of correct surgical repair. Other diagnostic procedures do not yield more information and can cause dangerous delays in intervention.     

Isolation of the Left Subclavian Artery in D-Transposition of the Great Arteries with Right Aortic Arch

Abnormal branching of the aorta associated with the right aortic arch (RAA) has been reported as isolation of left subclavian artery (ILSA), isolation of left common carotid artery, isolation of brachiocephalic artery. ILSA is a rare aortic branch anomaly that originates in the left subclavian artery from the pulmonary artery via ductus arteriosus. Several reports have described ILSA associated with 22q11.2 deletion syndrome and tetralogy of Fallot. Here, we present a very unusual case of RAA with ILSA associated with D-transposition of the great arteries and inferior vena cava interrupted with azygos continuation.     

Intravascular ultrasound in patients with suspected aortic dissection: comparison with transesophageal echocardiography]

Thirteen patients with suspected aortic dissection (two women, 11 men, age 61 +/- 10.8 years) underwent transesophageal echocardiography (TEE), intravascular ultrasound (IVUS), angiography, and in part computed tomography (CT). TEE was performed using 3.5 or 3.75 MHz ultrasound transducers. IVUS examination was done using a 6F 20 MHz "rotational-tip" IVUS catheter (Boston Scientific) advanced over a guiding-wire positioned in the ascending aorta by the "side-saddle" technique. In two patients it was not possible to advance the catheter into the abdominal aorta. Of the remaining 11 patients, eight had aortic dissection (six Typ III, one Typ II, and one Typ I, de Bakey classification). Two patients had aortic aneurysms without dissection and one patient had a perforation of the ascending aorta. TEE, CT, and angiography led to the correct diagnosis in all patients, while IVUS failed to provide precise information within the ascending aorta and the aortic arch. Reasons were the limited scanfield of the 20 MHz transducer and the inability to steer and position the IVUS catheter. Contrary to the limited value in the ascending aorta, IVUS could successfully scan the entire descending aorta, including the dissection membrane and the originating vessels, if the max. diameter was less than 4 cm. No adverse effects occurred. Intravascular ultrasound allows to scan the entire aorta in patients with suspected aortic dissection. The current limitations can be solved only by the introduction of steerable and/or low frequency catheters.     

Rupture of Aortic Dissection During Attempted Transesophageal Echocardiography

Transesophageal echocardiography (TEE) provides a rapid and accurate diagnosis in patients with dissection of the thoracic aorta. The procedure is considered to be safe. We report a case where rupture of a dissecting thoracic aneurysm occurred during attempted TEE in a patient, who had been clinically stable for 1 week. TEE was performed because aortic valve endocarditis was suspected, and the procedure did not include close surveillance of the blood pressure. Careful manipulation of the probe, adequate sedation, monitoring, and treatment of acute rises in blood pressure was recommended in patients with even a slight suspicion of dissection undergoing TEE.     

How the Dissection Laboratory Facilitates Integration of Learning: Presence of Abdominal Aortic Aneurysm with a Large Intracardiac Thrombus: A Rare Cadaver Finding

There is a debate among medical education experts on the application of dissection or prosection for learning anatomy. However, the literature reveals that the majority of published articles are in favor of dissection. In this article, we present a case of an abdominal aortic aneurysm (AAA) with intracardiac thrombus in a cadaver on routine dissection. We will discuss possible explanations for such finding and provide some insight into how this finding can support the significance of the cadaver-based teaching of anatomy of the medical students. Initially, the abdomen was dissected and exposed to study the abdominal structures in an anatomy class and later the thoracic region was dissected and all the clinical abnormalities were examined and documented. Autopsy of the clot was obtained for histopathology analysis. The intracardiac thrombus was present in the right atrium characterized by its projection into the superior vena cava, inferior vena cava, and the right ventricle. The AAA was extensive and inferior to the renal arteries constricting the entire inferior vena cava. Moreover, associated findings included presence of numerous collaterals in the thoracic region near the superior vena cava; histological examination of the clot showed extensive population of leukocytes. There were enlarged mediastinal lymph nodes. Our cadaver showed an excellent model for integrating between clinical anatomy and pathology by triggering medical students to think of normal and abnormal structures: often called “thinking outside the box.” Such an effort might help them in developing their thought processes and future medical careers.     

Aortopulmonary Artery Fistula: Ruptured Aneurysm of the Distal Aortic Arch into the Pulmonary Artery

Aortopulmonary artery fistula is uncommon, but the clinical outcome is often lethal. A 76‐year‐old man with a history of acute thoracic aortic dissection 6 years previously was admitted with dyspnea. A chest x‐ray showed pleural effusion and pulmonary congestion. Transthoracic echocardiography revealed preserved systolic function, but continuous and abnormal flow from the distal aortic arch into the pulmonary artery (PA). Transesophageal echocardiography (TEE) in the Doppler color‐flow mode demonstrated a left‐to‐right shunt between a large distal aortic arch aneurysm and the left PA via an aortopulmonary fistula and a pressure gradient across the shunt of 56 mmHg. Contrast‐enhanced computed tomography showed that the aneurysm compressed the PA. Aortography also revealed a large distal aortic arch aneurysm and almost simultaneous contrast enhancement of the aorta and the PA. Right‐heart catheterization showed a significant increase in oxygen saturation between the right ventricle and the PA. A left‐to‐right shunt due to a distal aortic arch aneurysm rupturing into the left PA was diagnosed based on these findings. TEE was very helpful in confirming the presence and precise location of the fistula.     

Atherosclerosis of the aorta in patients with acute thoracic aortic dissection

BACKGROUND: The role of atherosclerosis in thoracic aortic dissection has not been established yet. Transesophageal echocardiography (TEE) is an imaging modality widely used in the diagnostic evaluation of thoracic aortic dissection, and it can detect aortic atherosclerotic plaques and assess their size and specific characteristics. METHODS AND RESULTS: One hundred consecutive patients with thoracic aortic dissection and adequate imaging of the thoracic aorta by TEE were studied. The type of dissection (proximal or distal) and the presence and the degree of aortic atherosclerosis were defined. Proximal aortic dissection (Stanford type A) was found in 64 patients. Patients with proximal dissection were younger than those with distal (type B; 58+/-13 vs 67+/-11 years, p<0.001). The prevalence of arterial hypertension was higher in patients with distal dissection compared with those with proximal. Aortic atherosclerosis was present in less patients with proximal than with distal dissection (67% vs 94%, p<0.002). Logistic regression analysis revealed that patients with severe atherosclerosis were 7.6-fold more probable to have type B than type A dissection (p<0.001). CONCLUSION: Aortic atherosclerosis is more associated with distal than with proximal aortic dissection.     

Comparison of conventional and transesophageal echocardiography with magnetic resonance imaging for anatomical mapping of thoracic aortic dissection

Thirty-five consecutive patients with clinically suspected aortic dissection were subjected to a dual noninvasive imaging protocol using comprehensive echocardiography and ECG-triggered MRI with multi-slice spin echo and cine sequences in random order. The purpose of this dual imaging study was to compare the diagnostic accuracy of two-dimensional and color-coded Doppler echocardiography using the conventional transthoracic (TTE) and the transesophageal approach (TEE) with magnetic resonance imaging (MRI) for the exact morphologic evaluation and anatomical mapping of the thoracic aorta. The results of each diagnostic method were validated independently against the gold standard of intraoperative findings (n=17), necropsy (n=4) or contrast angiography (n=22).Compared to conventional transthoracic echocardiography both TEE and MRI were more reliable in detecting aortic dissections (TTE vs TEE: p<0.02; TTE vs MRI: p<0.01) and associated epiphenomena. Moreover, the reliability of TTE decreased significantly from proximal to distal segments of the aorta, e.g. from the ascending segment to the arch (p<0.05) and to the descending aorta (p<0.005), whereas the sensitivities of both TEE and MRI were excellent irrespective of the site of dissection. With regard to epiphenomena such as thrombus formation and entry location, MRI emerged as the optimal method for detailed morphologic information in all segments of the aorta. No serious side effects were encountered with either method.Thus, in patients with suspected acute or subacute aortic dissections the echocardiographic assessment should include the transesophageal approach for significant improvement of the moderate sensitivity and specificity of TTE. Both TEE and MRI are non-traumatic, safe and diagnostically accurate to identify and classify acute and subacute dissections of the thoracic aorta irrespective of their location. MRI provides superb anatomical mapping of all type A and B dissections and more detailed information on the site of entry and thrombus formation than TEE. These features of TEE and MRI may render retrograde contrast angiography obsolete in the setting of thoracic aortic dissection and may encourage surgical interventions exclusively on the basis of noninvasive imaging.     

Anomalies of the inferior vena cava in patients with iliac venous thrombosis

BACKGROUND: Cases of deep venous thrombosis in the lower extremities triggered by abnormalities of the vena cava have been reported. OBJECTIVE: To describe anomalies of the inferior vena cava in patients with deep venous thrombosis. DESIGN: Prospective, consecutive case series. SETTING: University Hospital, Graz, Austria. PATIENTS: 97 patients with deep venous thrombosis. INTERVENTION: Sonography, venography, or both to diagnose deep venous thrombosis; magnetic resonance angiography to image the inferior vena cava. MEASUREMENTS: Anomalies of the inferior vena cava imaged by magnetic resonance angiography. RESULTS: 31 of 97 patients showed thrombotic occlusion of iliac veins (common and external iliac vein [ n = 29] or external iliac vein [ n = 2]). Five of 31 patients (3 men, 2 women) had an anomaly of the inferior vena cava. Anomalies were missing inferior vena cava, hypoplastic hepatic segment, and missing renal or postrenal segments. Patients with anomalies were significantly younger than the 92 patients without (mean age+/-SD, 25+/-6 years vs. 53+/-19 years; P = 0.002). In 2 patients with anomalies, the thrombotic occlusion was recurrent. CONCLUSIONS: An anomaly of the inferior vena cava should be suspected if thrombosis involving the iliac veins is seen in patients 30 years of age or younger. Patients with both an anomaly and thrombosis may be at higher risk for thrombotic recurrence.     

Fortuitous rupture of aortic aneurysm: A catastrophic event affording time for surgical cure

The rupture of an aortic aneurysm is generally a fatal event, but occasionally the rupture will occur into an adjacent vascular structure, thereby preventing exsanguination and affording temporary survival. Three cases are presented illustrating the fortuitous nature of the rupture of an aortic aneurysm into a vascular structure. The first patient had an atherosclerotic abdominal aortic aneurysm that ruptured into the inferior vena cava and was successfully repaired. The second case demonstrates the formation of a fistula from the aorta to the left pulmonary artery in a patient with a syphilitic thoracic aortic aneurysm. In the third patient a dissecting aneurysm of the aortic root that communicated with the right ventricle after coronary bypass surgery was successfully repaired. Rarely, aortic aneurysms will rupture fortuitously into vascular capacitance structures. These three cases emphasize the need for early accurate diagnosis and the institution of appropriate surgical measures.     

Magnetic resonance tomography in the diagnosis of vascular lesions in hypertension patients

Fifty-six patients with arterial hypertension (AH) and various vascular disorders were investigated by magnetic resonance (MR) tomography. All patients were also subjected to radiopaque aortography. Twenty-seven normal subjects were taken as controls. They showed good visual images of thoracic and abdominal aorta and vena cava inferior in all tomographic sections, yet the frontal section proved the best for vessel visualization as it showed the vessels at length. MR tomograms were similar in patients with essential hypertension, stage I-IIA and in normal subjects, while patients with more than 5-year essential hypertension, stage IIB-III, demonstrated a convoluted aorta (sagittal and frontal sections), with an S-shaped convolution in a number of cases; their aortic diameter was increased owing to a thicker vascular wall as well as a wider lumen. Patients with renovascular hypertension showed abnormal renal arteries featuring pre-stenotic dilatation and stenosed portions. Iliac arterial occlusions were clearly seen. Patients with wide-spread atherosclerosis and nonspecific aorto-arteritis showed a variety of thoracic or abdominal aortic aneurysms.     

Two dimensional echocardiographic diagnosis of situs.

At present there is no reliable method of recognising atrial isomerism by two dimensional echocardiography. We therefore used two dimensional echocardiography to examine 158 patients including 25 with atrial isomerism and four with situs inversus. Particular attention was paid to the short and long axis subcostal scans of the abdomen. Using the position of the inferior vena cava and the aorta with respect to the spine it was possible to separate those with situs solitus from the others. Two false positives for abnormal situs had exomphalos. In situs solitus the aorta lay to the left of the spine and the inferior vena cava lay to the right. One patient with situs solitus and azygos continuation of the inferior vena cava also had inferior vena cava to right atrial connection. In the four patients with situs inversus the mirror image of the normal pattern was present. In nine patients with right isomerism the inferior vena cava and aorta ran together on one or other side of the spine. The inferior vena cava, anterior to the aorta at the level of the diaphragm, received at least the right hepatic veins (normal or partial anomalous hepatic venous connection). Of the 16 patients with left isomerism, 14 had azygos continuation of the inferior vena cava which was visualised posterior to the aorta in all but two. All patients with left isomerism had total anomalous hepatic venous connection to one or both atria via one or two separate veins. Two dimensional echocardiography therefore provides the means of detecting abnormal atrial situs and of diagnosing right or left isomerism in the great majority of patients, if not all.     

胸主动脉病变术中应用经食管超声心动图的初步探讨

目的：探讨胸主动脉疾病的术中应用经食管超声心动图（ＴＥＥ）的价值及适应证。方法：本文报道８例（１５～６３岁，平均年龄４４．５岁）不同类型胸主动脉疾病术中ＴＥＥ监测结果。病例包括先天性主动脉瓣上狭窄、升主动脉瘤、主动脉夹层及主动脉夹层伴假性动脉瘤、胸降主动脉假性动脉瘤、主动脉瓣脱垂等。结果：８例患者的术中检查与术前诊断全部吻合。术中ＴＥＥ发现１例主动脉夹层累及左锁骨下动脉，而术前磁共振成像未能提示。此外，术中ＴＥＥ还显示２例胸降主动脉内的粥样硬化斑块。结论：初步显示术中ＴＥＥ可即刻评价手术效果，对拟行主动脉瓣成形术的患者最有价值；为避免升主动脉粥样斑块的脱落导致术后体循环尤其是脑栓塞，对于高龄患者也积极提倡术中ＴＥＥ监测。     

体外循环中体循环血浆内皮素-1的变化

目的观察体外循环(CPB)手术中体循环血浆内皮素-1(ET-1)的变化,并探讨其变化的原因.方法16例心脏病患者,于主动脉阻断前即刻,主动脉开放后1、3、5分,分别取升主动脉根部血及冠状静脉窦血,于主动脉阻断前即刻,主动脉开放10分,停CPB时分别取上、下腔静脉血和升主动脉根部血,测定血浆ET-1含量.结果主动脉阻断前即刻,主动脉开放后1、3、5分,冠状静脉窦血和升主动脉根部血血浆ET-1水平无显著差异;停CPB时下腔静脉血浆ET-1水平显著高于主动脉阻断前即刻(P＜0.05),也显著高于同时点升主动脉根部血血浆ET-1水平(P＜0.05).主动脉阻断前即刻,主动脉开放后10分,两者无显著差异;CPB期间上腔静脉血和主动脉根部血血浆ET-1水平无显著升高,两者也无显著差异.结论CPB手术中体循环血浆中升高的ET-1主要来源于腹部脏器,而不是心肌组织.