Ultrasonic diagnosis of infrahepatic interruption of the inferior vena cava with azygos (hemiazygos) continuation

Two patients with infrahepatic interruption of the inferior vena cava (IVC) with azygos (hemiazygos) continuation were examined ultrasonographically and the findings compared to seven normal studies. Pathognomonic ultrasonographic features of this anomaly are easily demonstrated and include absence of the IVC at the level of the liver and independent drainage of the confluence of hepatic veins into the right atrium. Conventional venography can now be replaced by ultrasonic examination to establish this diagnosis. The embryology, anatomy and clinical implications of this entity are discussed.     

Microvascular transplantation in the salvage of lower extremity trauma in the elderly

In the cadaver of an 86 year old man the inferior segment of the azygos vein could not be found. Furthermore, a normally developed hemiazygos vein drained the right and left intercostal veins from T 10 to T 6. This vessel finally curved towards the right to reach the superior vena cava after having drained the right superior intercostal veins. The left superior intercostal vein ended in a short vessel draining into the left brachiocephalic vein. This condition may be represented in a standard chest radiograph by the so-called "aortic nipple". Agenesis of the azygos vein, suspected because of the presence of this radiological sign, should be confirmed in the living by means of computerized tomography. This can clarify the anatomy of the mediastinal vessels precisely. Embryological pattern of the azygos system accounting for its possible defects is discussed.     

Alveolar echinococcosis of the liver: sequelae of chronic inferior vena cava obstructions in the hepatic segment

BACKGROUND: The clinical pattern and long-term course of chronic inferior vena cava (IVC) obstructions are variable and depend on the underlying cause, the segment involved, and the extension of secondary thrombosis. Pertinent data on IVC obstructions in well-defined series of patients are lacking. We report the sequelae of chronic IVC obstructions in the hepatic segment in 11 consecutive patients derived from a cohort of 104 patients with alveolar echinococcosis of the liver. METHODS: Based on the results of computed tomography scans, 11 patients (7 men, 4 women; mean age, 53.4 years) with IVC obstructions were selected from an ongoing prospective long-term chemotherapy trial comprising 104 patients with alveolar echinococcosis studied at yearly intervals according to a protocol. Obstruction of the IVC in the 11 patients existed for a mean duration of 8.6 years. In these patients, magnetic resonance imaging was performed to assess the morphologic features and extension of the IVC obstruction, as well as the collateral venous pathways. Patency and valvular function of the femoropopliteal veins were analyzed by color-coded duplex ultrasonography. RESULTS: Total occlusions of the IVC were evident in 8 patients (73%) and subtotal stenoses in 3 patients (27%). Only 4 patients (36%) exhibited signs and symptoms of chronic venous insufficiency of the lower extremities; 2 (18%) of the 4 had a history of swelling in the lower extremity. Seven patients (64%) had no lower extremity symptoms. One patient had a history of pulmonary embolism. Abdominal collateral veins were documented in 5 patients (45%) by using magnetic resonance imaging; however, they were clinically evident in only 3 patients (27%). In the 8 patients with IVC occlusion, thrombosis ended at the confluence of the hepatic veins. Obstruction of the IVC was limited to the hepatic segment in 2 patients (18%) and extended to the distal IVC or the iliofemoral veins in 6 patients (54%). Chronic venous insufficiency was present only if the femoropopliteal veins had been involved in the thrombotic process, showing residual venous obstruction, valvular incompetence, or both. Bilateral renal vein thrombosis with moderate proteinuria was observed in 2 patients (18%). The main collateral drainage was achieved through the ascending lumbar, azygos, and hemiazygos veins. CONCLUSIONS: In patients with alveolar echinococcosis, obstruction of the IVC in the hepatic segment often develops asymptomatically and rarely leads to the impairment of renal function. The collateral circulation fully compensates for obstruction of the IVC. Thrombotic involvement and valvular incompetence of the femoropopliteal veins seems to determine the development of chronic venous insufficiency of the lower extremities.     

Kinetic and spectroscopic characterization of an intermediate peroxynitrite complex in the nitrogen monoxide induced oxidation of oxyhemoglobin

A rare case of absence of the azygos vein associated with double superior vena cava is presented. Imaging findings on plain chest film and on contrast-enhanced computed tomography are described, and the embryology of azygos and hemiazygos veins is reviewed.     

Traumatic aortic rupture--diagnosis with transesophageal echocardiography

A quick and exact diagnosis of a ruptured aorta can be achieved by different imaging methods (CT, TEE, NMR). In this case report, we describe a 36-year-old patient, who suffered rupture of the thoracic aorta in the isthmus region during a car accident. CT was suspicious of aortic rupture and the exact localization of the rupture site was visualized by TEE. It was confirmed during the operation when an aortic prosthesis was implanted. The high mortality of aortic rupture could possibly be lowered by early application of TEE. Preoperative angiography seems not to be necessary.     

Technical note: Detection of bovine kappa-casein variants A, B, C, and E by means of polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP)

OBJECTIVE: The purpose of this study was to describe the CT imaging features of preaortic esophageal veins in 10 patients with liver cirrhosis. CONCLUSION: Preaortic esophageal veins deriving from the paraesophageal varices course anterior to the descending aorta and drain into the hemiazygos vein. Preaortic esophageal veins are anatomically identical to extrinsic esophageal veins. The diameter of the veins we studied ranged from 1 to 8 mm (mean, 3.1 mm). Two preaortic esophageal veins were noted in each of two patients.     

The pivotal role of transesophageal echocardiography in the management of traumatic thoracic aortic rupture with associated intra-abdominal hemorrhage

Rupture of the thoracic aorta after blunt trauma, particularly when associated with multiple injuries, presents a major problem of resuscitation and management. Transesophageal color Doppler echocardiography (TEE) during laparotomy played a major role in confirming the diagnosis of thoracic aortic rupture in a patient.     

A new noninvasive technique for imaging atherosclerotic plaque in the aortic arch of stroke patients by transcutaneous real-time B-mode ultrasonography: an initial report

BACKGROUND AND PURPOSE: Aortic arch atherosclerotic plaque is a probable source of atheroembolic stroke. Transesophageal echocardiography (TEE) has been used to image the aorta of patients with stroke to identify atherosclerotic plaque. TEE is moderately invasive and does not always visualize plaques present in the distal ascending aorta and proximal aortic arch. METHODS: In the current study, transcutaneous B-mode ultrasonography was performed to image the aortic arch through a lateral supraclavicular window, and the results were compared with those of TEE in 20 patients. The aorta was subdivided into the proximal ascending (PAsc), distal ascending (DAsc), proximal aortic arch (PAA), and distal aortic arch (DAA) to be certain the plaques identified by each technique were the same. Plaques were characterized as simple (<4 mm thick) or complex (>4 mm thick). RESULTS: In the PAsc, 8 simple plaques were identified with TEE but not with B-mode. In the DAsc, 1 complex plaque was identified with both techniques, and B-mode identified 1 additional complex and 1 simple plaque. In the PAA, 6 simple and 5 complex plaques were identified by both techniques, and TEE identified 1 additional complex plaque. In the DAA, TEE identified 2 simple and 2 complex plaques; B-mode identified 3 complex plaques. CONCLUSIONS: B-mode imaging compared favorably with TEE in identification of plaques in the aortic arch and distal ascending aorta, although it could not identify simple plaques in the proximal ascending. B-mode could visualize plaques not seen by TEE in the distal ascending aorta. B-mode ultrasonography is complementary to TEE in performance of a comprehensive assessment of plaque in the aortic arch and provides a noninvasive method for sequential studies of plaques that can be visualized.     

Veins of Retzius at CT during arterial portography: anatomy and clinical importance

PURPOSE: To classify the veins of Retzius demonstrated at computed tomography (CT) during arterial portography (CTAP) on the basis of anatomic location and to evaluate the relationship between the frequency of CT visualization and associated disease. MATERIALS AND METHODS: The authors reviewed axial CTAP scans from 130 patients. Patients were classified into one of two groups: patients with liver cirrhosis (group 1 [n = 81]) and patients without liver cirrhosis (group 2 [n = 49]). RESULTS: The pathways of the veins of Retzius were classified as follows: (a) The ileocolic vein drained into the inferior vena cava (IVC) or the right renal vein through the right gonadal vein (n = 61); (b) the pancreaticoduodenal vein drained into the IVC (n = 8); (c) the proximal branches of the superior mesenteric vein drained into the left gonadal vein (n = 6); and (d) the ileocolic vein drained directly into the IVC (n = 5). The veins of Retzius were demonstrated in 41 (51%) of the 81 patients in group 1 and 26 (53%) of the 49 patients in group 2. There was no statistically significant difference between the two groups. CONCLUSION: The veins of Retzius were demonstrated at CTAP in approximately 50% of patients with and 50% of patients without liver cirrhosis.     

Abdominal CT findings when the superior vena cava, brachiocephalic vein, or subclavian vein is obstructed

OBJECTIVE: We evaluated findings on contrast-enhanced abdominal CT scans that suggest obstruction of the superior vena cava, brachiocephalic vein, or subclavian vein. SUBJECTS AND METHODS: We conducted a retrospective review of 22 patients with superior vena caval, brachiocephalic vein, or subclavian vein obstruction and analyzed the upper abdominal images on a chest CT scan or an abdominal CT scan. We assessed collateral vessels in the upper abdomen to answer the following question: Did enhancement approach undiluted IV contrast or were there other findings? In the second part of our study, we conducted a prospective review of abdominal CT scans of 200 patients without known mediastinal disease or known upper extremity venous occlusion to determine the frequency of abnormal enhancement of these vessels in a healthy population. RESULTS: The groups of collateral vessels revealed on abdominal CT scans were azygos or hemiazygos veins, internal mammary veins, lateral thoracic and superficial thoracoabdominal veins, vertebral venous plexus veins, and small mediastinal collateral veins. In the retrospective series, one patient had focal enhancement of the liver and early inferior vena caval enhancement due to collateral vessels. In the prospective series, abdominal CT scans of two patients (1%) revealed dense undiluted enhancement of one or more groups of collateral vessels: One patient had an ipsilateral pacemaker, and the other patient had an anterior neck phlegmon to the upper mediastinum. Both conditions may have been factors in the revealing of the collateral vessels. Two other patients (1%) in the prospective series had mild to moderate vessel enhancement that was less than that from undiluted contrast material. In one of these patients, the enhancement was related to abdominal wall hyperemia after surgery. In the other patient, enhancement may have been the result of ipsilateral axillary nodes. CONCLUSION: On upper abdominal CT scans, dense undiluted contrast material in the collateral vessel groups that we studied suggests possible obstruction of the superior vena cava, brachiocephalic vein, or subclavian vein.     

Large-scale screening for factor V Leiden mutation in a north-eastern German population

A 37-year-old man was referred with thoracic pain after a deceleration trauma. He also had a cerebral contusion and a wrist fracture. There were no sings of hypovolemic shock. Computerized tomography (CT) of the chest and transoesophageal echocardiography (TEE) demonstrated a type B aortic dissection originating just distal to the left subclavian artery. There was a patent false lumen without rupture or distal ischaemia. Conservative treatment was given. A paralytic ileus developed and abdominal complaints persisted for several months. Angiography showed normal patency of mesenteric vessels. On follow-up, 3 years after the accident a slight aortic dilation was found on CT thorax without development of a post-dissection aneurysm. Blunt thoracic injury to the aorta usually gives rise to aortic rupture in the region of the isthmus, which can be complete or partial. In the latter case a false aneurysm may develop. An intimal tear after blunt trauma leading to type B aortic dissection rarely occurs. General principles regarding treatment of type B dissection also apply to this particular condition.     

Cytokines and bioincompatibility

OBJECTIVES: This study explored the mechanisms linking clinical and precordial echocardiographic predictors to thromboembolism in atrial fibrillation (AF) by assessing transesophageal echocardiographic (TEE) correlations. BACKGROUND: Clinical predictors of thromboembolism in patients with nonvalvular AF have been identified, but their mechanistic links remain unclear. TEE provides imaging of the left atrium, its appendage and the proximal thoracic aorta, potentially clarifying stroke mechanisms in patients with AF. METHODS: Cross-sectional analysis of TEE features correlated with low, moderate and high thromboembolic risk during aspirin therapy among 786 participants undergoing TEE on entry into the Stroke Prevention in Atrial Fibrillation III trial. RESULTS: TEE features independently associated with increased thromboembolic risk were appendage thrombi (relative risk [RR] 2.5, p = 0.04), dense spontaneous echo contrast (RR 3.7, p < 0.001), left atrial appendage peak flow velocities < or = 20 cm/s (RR 1.7, p = 0.008) and complex aortic plaque (RR 2.1, p < 0.001). Patients with AF with a history of hypertension (conferring moderate risk) more frequently had atrial appendage thrombi (RR 2.6, p < 0.001) and reduced flow velocity (RR 1.8, p = 0.003) than low risk patients. Among low risk patients, those with intermittent AF had similar TEE features to those with constant AF. CONCLUSIONS: TEE findings indicative of atrial stasis or thrombosis and of aortic atheroma were independently associated with high thromboembolic risk in patients with AF. The increased stroke risk associated with a history of hypertension in AF appears to be mediated primarily through left atrial stasis and thrombi. The presence of complex aortic plaque distinguished patients with AF at high risk from those at moderate risk of thromboembolism.     

Successful repair of total anomalous pulmonary venous connection and incomplete endocardial cushion defect associated with left isomerism

Successful repair of a 8-month-old girl with polysplenia was reported. The cardiovascular anomalies were TAPVC (II b), incomplete ECD, interruption of inferior vena cava with hemiazygos continuation, bilateral superior vena cava, and left superior vena cava draining into the coronary sinus. Cardiopulmonary bypass was established with ascending aortic perfusion and caval cannulation. A left superior vena cava was directly cannulated after establishing partial bypass. In this case the left pulmonary vein drained into the right atrium near the orifice of the coronary sinus, so the atrial septal flap was made and sutured between the orifice of the left pulmonary vein and the coronary sinus in order to avoid late pulmonary vein obstruction. Then, atrium was separated by an intraatrial baffle which was sutured to the atrial septal flap. Recently, it becomes possible to surgical repair of polysplenia syndrome according to the advancements of the diagnostic methods, cardiopulmonary bypass, and the technique of the open heart surgery.     

A case of aortic dissection after the termination of cardiopulmonary bypass

We report, a case of aortic dissection after the termination of cardiopulmonary bypass (CPB), which was diagnosed by transesophageal echocardiography (TEE). A 70-year old male with aortic regurgitation received aortic valve replacement. After the termination of CPB, the aortic dissection was diagnosed by TEE. Furthermore wall motion abnormality was found by TEE, and aorto-coronary bypass was performed after observation by TEE. This case report suggests that TEE is useful not only for diagnosis but also for therapeutic orientation of aortic dissection.     

Translumbar placement of inferior vena caval catheters: a solution for challenging hemodialysis access

Access to the central venous circulation for hemodialysis has traditionally been achieved via the subclavian or jugular venous routes. With ongoing improvements in medical management, many hemodialysis recipients develop exhaustion of these routes and require alternative means of central venous access. Inferior vena caval (IVC) catheters have been placed with a percutaneous translumbar approach to allow central venous access for chemotherapy, harvesting of stem cells, and total parenteral nutrition. Translumbar placement of IVC catheters has become accepted by some as a useful and reliable alternative in patients who require long-term hemodialysis but have exhausted traditional access sites. IVC catheters have been placed in patients with IVC filters, and IVC filters have been placed in patients with IVC catheters. Complications include those associated with central venous catheters, for example, sepsis, fibrin sheaths, and thrombosis. A complication specific to placement of IVC hemodialysis catheters is migration of the catheter into the subcutaneous soft tissues, retroperitoneum, or iliac veins. Translumbar placement of IVC catheters is performed only in patients considered to have few or no other medical options and is not intended as a primary means of central venous access.     

Interference by carbohydrate substrates, flavonoids, and monosaccharide derivatives on bacterial beta-D-glucuronidase assays

PURPOSE: To determine if suprarenal placement of inferior vena cava (IVC) filters is associated with renal dysfunction or other complications. MATERIALS AND METHODS: Case files of all patients with suprarenal vena caval filter placement since 1985 were reviewed for clinical and biochemical evidence of renal dysfunction and renal vein thrombosis. The occurrence of associated complications, including IVC occlusion, filter fracture, device migration, and recurrence of pulmonary embolism was also recorded. RESULTS: Twenty-two (2.9%) of 764 IVC filters were implanted above the renal veins: titanium Greenfield filter modified hook (TGF-MH) (n = 16), LGM type I (n = 2), LGM type II (n = 2), and Bird's Nest (BN) type I (n = 2). Reasons for suprarenal filter placement included thrombus to the level of the renal veins (n = 9), failure or poor position of the infrarenal filter (n = 6), pregnancy or intent of pregnancy (n = 4), and the malpositioning of BN filters above the renal veins (n = 2). A single patient demonstrated evidence of transient renal dysfunction. Pulmonary embolus was found at autopsy in one patient. Abdominal radiographs were obtained at follow-up of 18 patients and demonstrated a 2 cm or more migration of the filter in five patients (27.7%). This rate of migration was significantly different from the 3% migration rate reported by the authors' institution in the follow-up of 320 infrarenal IVC filters. There was one filter fracture (5.5%.) and penetration of the IVC occurred in one patient (5.5%). CONCLUSION: Follow-up indicates suprarenal IVC filter placement is safe, and no evidence of permanent renal dysfunction after placement was found. Filter migration was the most frequent complication, but no clinical sequelae were noted with these patients.     

Aneurysmal bulb dilation of the azygos vein: radiological and clinical significance

An aneurysm of the azygos vein is usually detected in the course of routine chest X-rays. It presents as a sharply circumscribed tumor shadow in the area of the right tracheobonchial angle or as an enlargement of the upper right mediastinum. A tentative diagnosis is supplemented both by further X-rays in a supine position in combination with the Valsalva and Müller tests and by tomography. The most frequent cause of an azygos aneurysm found in our material is aplasia of the inferior vena cava. Infrahepatic interruption of the inferior vena cava with azygos continuation can also be an associated malformation. Therefore, bilateral pelvic phlebography with visualization of the retroperitoneal venous and azygos systems is mandatory for establishing the correct, complete diagnosis. We have found no concomitant hemodynamic derangements. It is important to note that under these circumstances no therapy is indicated.     

Planimetric quantification of aortic valve stenoses using multiplanar transesophageal echocardiography

Standard techniques used in order to quantify the severity of aortic valve stenoses in clinical practice comprise: transthoracic echocardiography, namely, by determining maximum and mean transvalvular gradients and evaluating aortic valve areas, as well as invasive techniques which quantify aortic valve areas through hemodynamic pressure measurements and application of the Gorlin formula. Since the introduction of the multiplane TEE technique, it has become feasible to scan the aortic valve in a strictly horizontal plane and quantify the aortic valve orifice by planimetry. In this study, we investigated 23 patients with various degrees of aortic valve stenoses. We compared aortic valve areas, which had been planimetrically determined by multiplane TEE scans, and mean aortic valve gradients (standard TEE technique) with pressure gradients and valve areas derived from hemodynamic measurements obtained during cardiac catheterization, and have found that the valve areas as well as the mean pressure gradients correlate well.     

A unique method of closure for an aortocaval fistula in association with a ruptured abdominal aortic aneurysm: report of a case

We report herein the case of a 78-year-old man in whom an aortocaval fistula caused by spontaneous rupture of an abdominal aortic aneurysm (AAA) was successfully treated by a unique surgical technique. The aortocaval fistula had been revealed by an aortography after the patient presented with high-output heart failure. During the operation, massive bleeding from the fistula was evident. The fistula measured 2 cm in diameter, and was located between the right posterior wall of the AAA and the inferior vena cava (IVC). Direct suturing of the defect in the IVC failed to close the fistula because the tissue around it would not hold together due to degeneration. However, the bleeding was finally able to be controlled by plugging the fistula with isolated and properly trimmed omentum packed within the excluded aneurysmal sac. Unfortunately, the patient died due to respiratory failure on the 201st postoperative day. A pathological autopsy revealed that the aortocaval fistula had been closed by fibrous tissue and that the IVC was patent. Although such a drastic operative measure to repair an aortocaval fistula has never before been reported, it could be an alternative when direct closure proves unsuccessful.     

Resolution of an aortic mobile mass with anticoagulation without evidence of arterial embolism

The prognostic significance of aortic mobile debris detected by transesophageal echocardiography (TEE) in patients without history of embolism has not been established. A mobile aortic arch mass was found by TEE in a 59-year-old man with coronary artery disease, and with rheumatic mitral valve disease, and with no embolic symptoms. The patient was anticoagulated for 6 weeks and the mass was no longer seen on repeated TEE. He had no embolic symptoms during 9 months of follow-up. Different therapeutic approaches to mobile aortic debris are discussed and anticoagulant treatment of asymptomatic cases is advocated.