Hemiazygos Continuation Research Articles

A dilemma in the electrophysiology lab: where is the coronary sinus in a patient with left inferior vena cava with hemiazygos continuation?

Occasionally, electrophysiological interventions are complicated by an unusual or an anomalous cardiovascular anatomy. We report our experience of a case of situs ambiguous and symptomatic heart failure of which anomalous venous anatomy and coronary sinus variation had prevented a successful endocardial placement of a left ventricular lead for cardiac synchronization therapy.

Incidentally Detected Situs Ambiguous in Adults

Situs ambiguous is rare congenital anomaly in adults. In 2 adult patients who admitted for different cardiac problems, situs ambiguous with polysplenia was detected. A 42-year-old male admitted for radio frequent catheter ablation of atrial fibrillation, and he had left-sided inferior vena cava (IVC), hepatic segment of IVC interruption with hemiazygos continuation, multiple spleens and intestinal malrotation. And in a 52-year-old female case who was hospitalized due to infective endocarditis after implanting pacemaker for sick sinus syndrome, multiple spleens, left-sided stomach, bilateral liver with midline gallbladder, and left-sided IVC were found. Those findings were consistent with situs ambiguous with polysplenia, but their features were distinctive.

Congenital lobar emphysema associated with polysplenia syndrome

Polysplenia, or left isomerism, is a rare heterotaxy syndrome characterized by bilateral bi-lobed lungs, bilateral pulmonary atria, a symmetrical midline liver, and multiple aberrant splenic nodules. We report a case of polysplenia associated with congenital lobar emphysema apart from other typical anomalies. Such an association has not been previously reported. The patient was a young male with progressive exertional breathlessness referred for high resolution CT of the lungs. CT, MRI and echocardiography revealed (in addition to congenital lobar emphysema of right lung) a hemiazygos continuation of the inferior vena cava, a persistent left superior vena cava, multiple splenunculi in the right hypochondrium, midline liver, bilateral bilobed lungs, a large pulmonary artery (suggestive of severe pulmonary artery hypertension) and a large VSD—a typical constellation of findings described in polysplenia syndrome.

Patent abdominal subcutaneous veins caused by congenital absence of the inferior vena cava: a case report

IntroductionPatent paraumbilical and abdominal subcutaneous veins are found frequently as collaterals in patients due to portal hypertension mainly in liver cirrhosis.Case presentationFor evaluation of portal hypertension in a 72-year-old Caucasian man without liver cirrhosis, magnetic resonance imaging with gadolinium contrast-enhancement was performed and demonstrated a missing inferior vena cava. A blood return from the lower extremities was shown through enlarged collateral veins of the abdominal wall, vena azygos and hemiazygos continuation, and multiple liver veins emptying into the right cardiac atrium. We describe a rare case of abdominal subcutaneous wall veins as collaterals caused by a congenitally absent infrarenal inferior vena cava with preservation of a hypoplastic suprarenal segment.ConclusionKnowledge of these congenital variations can be of clinical importance and it is imperative for the reporting radiologist to identify these anomalies as they can have a significant impact on the clinical management of the patient.

Intraatrial Baffle Repair of Anomalous Systemic Venous Return Without Hepatic Venous Drainage in Heterotaxy Syndrome

A 7-month-old boy with heterotaxy syndrome had partial atrioventricular septal defect and interrupted inferior vena cava with hemiazygos continuation to a left superior vena cava. The left side of the common atrium receiving all the venous drainage was in connection with the left ventricle and the aorta. The small atrium and the proximity of the pulmonary and hepatic vein orifices precluded complete baffling. This report describes an intraatrial baffle repair of anomalous systemic venous return without hepatic venous drainage. This resulted in good oxygenation postoperatively, with oxygen saturation ranging from 93% to 98%.

64-slice spiral CT appearance of congenital anomalies of the inferior vena cava

Objective To evaluate the imaging findings of congenital anomalies of inferior vena eava (IVC) with 64-slice spiral CT. Methods Between January 2008 and May 2009, 6986 patients who had routine abdominal 64-row multi-detector computed tornography were retrospectively analyzed for congenital anomalies of IVC. Results Among 6986 cases, 25 cases with congenital anomalies of IVC were identified. Six case were left IVC, showing IVC left to the aorta inferior to the renal hilum. Ten cases were double IVC, showing two IVC besides the aorta inferior to the renal hilum. Five cases were abnormal renal vein, showing retroaortic and circumaortic left renal vein. Two cases were IVC interruption with collateral circultion by azygous or hemiazygous vein, contrast-enhanced CT scan showing deficiency of the IVC between hepatic and renal hilums, the enlarged azygos vein communicating with IVC at renal level and the hepatice vein draining into the right atrium. Venography showed that IVC draining into the superior vena cava through azygous or hemiazygous veins. One case was interruption of the IVC with portal vein continuation, contrastenhanced CT scan showing the communication between the IVC and portal vein. One case was hemiazygos continuation of a left IVC, contrast-enhanced CT scan demonstrating dilatation hemiazygos continuation of a left IVC and jointed the azygos vein. Conclusion The 64-slice spiral CT can be a diagnostic standard for congenital anomalies of inferior vena cava. Key words: Inferior vena cava; Abnormalities; Tomography,X-ray computed

Congenital extrahepatic portosystemic shunt associated with heterotaxy and polysplenia

Heterotaxy with polysplenia is associated with many cardiovascular anomalies including the occasional occurrence of congenital extrahepatic portosystemic shunts (CEPS). Missing this anomaly can lead to inappropriate and ineffective therapy. To emphasize the importance and associated anatomy of CEPS in conjunction with heterotaxy with polysplenia. Review of three young children who presented with cyanosis and pulmonary hypertension without a cardiac etiology. They were known (1) or discovered (2) to have heterotaxy with polysplenia. There was absence of the intrahepatic inferior vena cava (IVC) with azygos or hemiazygos continuation in all three cases. In spite of normal liver function, they were discovered to have large portosystemic shunts, splenorenal in location, along with diffuse peripheral pulmonary arterial dilatation suggestive of CEPS (Abernethy malformation) with hepatopulmonary or, more accurately, portopulmonary syndrome. All CEPS were ipsilateral to the spleens. Patency of the portal veins in these cases allowed for percutaneous shunt closure with resolution of cyanosis. CEPS is associated with heterotaxy with polysplenia and can be symptomatic because of pulmonary arteriovenous (AV) shunting. Portal and hepatic vein patency are critical for determining feasibility of CEPS closure.

CT findings in unilateral hepatopulmonary syndrome after the Fontan operation

Patients with complex congenital heart defects palliated by connecting the systemic veins directly to the pulmonary circulation are known to develop hepatopulmonary syndrome (HPS). Although rare, HPS can develop following the Fontan operation. To present and analyse the CT findings of HPS in patients with a Fontan circulation. From May to December 2005, six patients with HPS following the completion of a Fontan circulation were evaluated. CT findings were reviewed and were compared with angiographic findings. All six patients showed unilateral involvement. All patients except one had inferior vena cava (IVC) interruption with azygos continuation. CT scans showed abnormal vascular dilatation in one lung, and properly demonstrated the anatomy causing the hepatic venous blood to flow preferentially into one lung. These CT findings correlated well with the angiography findings. HPS that develops after the Fontan procedure is typically unilateral and is often associated with IVC interruption and azygos or hemiazygos continuation. CT demonstrates dilatation of pulmonary vessels in the affected lung and may be able to demonstrate the underlying anatomical cause for the predilection of hepatic venous flow to the contralateral lung.

Multiple anatomical malformations in 25-year old patient with heterotaxy: Case report

Heterotaxy or situs ambiguus is a rare congenital disorder, characterized by abnormal situs with either left or right isomerism that usually coincides with A complex malformation. The classic left isomerism or bilateral left-sidedness or heterotaxy syndrome with polysplenia implies that patients have bilateral bilobed lungs, bilateral pulmonary atria, a centrally located liver, a stomach in indeterminate position, and multiple spleens, occasionally associated with interruption of the inferior cava with azygos or hemiazygos continuation. We present a case of situs ambiguus associated with severe heart and vascular abnormalities in a 25-year-old male patient. On the admittance to our clinic the patient had history of biliary colic, moderate jaundice of the conjunctive and sclerae, and severe central cyanosis. The echocardiography revealed a large atrial septal defect, complete absence of the interventricular septum resulting in the single ventricle and the inversion of atria. The angiography obtained the hypoplastic inferior vena cava continuing with azygos vein that flowed into the left superior vena cava. The computerized tomography scans showed three splenuli in the right upper quadrant of the abdomen, and a single gallstone appeared in the left-positioned gallbladder. The contrast radiography showed complete transposition of the guts and stomach. To our knowledge, our patient with described severity of the anomalies had the longest life span in this part of Europe, although the longer survivors have been described in the other parts of the world. Furthermore, clinical characteristics of both left and right isomerism have been obtained in the patients with anatomically pronounced left isomerism.

Magnetic Navigation and Catheter Ablation of Right Atrial Ectopic Tachycardia in the Presence of a Hemi‐Azygos Continuation: A Magnetic Navigation Case Using 3D Electroanatomical Mapping

We report on a 63-year-old female patient in whom an electrophysiologic study discovered a hemi-azygos continuation. Using the magnetic navigation system, remote-controlled ablation was performed in conjunction with the 3D electroanatomical mapping system. Failing the attempt to advance a diagnostic catheter from the femoral vein, a diagnostic catheter was advanced via the left subclavian vein into the coronary sinus. The soft magnetic catheter was positioned in the right atrium via the hemi-azygos vein, and 3D mapping demonstrated an ectopic atrial tachycardia. Successful ablation was performed entirely remote controlled. Fluoroscopy time was only 7.1 minutes, of which 45 seconds were required during remote navigation. Remote-controlled catheter ablation using magnetic navigation in conjunction with the electroanatomical mapping system proved to be a valuable tool to perform successful ablation in the presence of a hemi-azygos continuation.

The Diaphragmatic Crura and Retrocrural Space: Normal Imaging Appearance, Variants, and Pathologic Conditions

The retrocrural space (RCS) is a small triangular region within the most inferior posterior mediastinum bordered by the two diaphragmatic crura. Multiplanar imaging modalities such as computed tomography and magnetic resonance imaging allow evaluation of the RCS as part of routine examinations of the chest, abdomen, and spine. Normal structures within the retrocrural region include the aorta, nerves, the azygos and hemiazygos veins, the cisterna chyli with the thoracic duct, fat, and lymph nodes. There is a wide range of normal variants of the diaphragmatic crura and of structures within the RCS. Diverse pathologic processes can occur within this region, including benign tumors (lipoma, neurofibroma, lymphangioma), malignant tumors (sarcoma, neuroblastoma, metastases), vascular abnormalities (aortic aneurysm, hematoma, azygos and hemiazygos continuation of the inferior vena cava), and abscesses. An understanding of the anatomy, normal variants, and pathologic conditions of the diaphragmatic crura and retrocrural structures facilitates diagnosis of disease processes within this often overlooked anatomic compartment.

Hemiazygos Venous Additional Pulmonary Flow for Successful Total Cavo-pulmonary Connection

Patients who underwent only Glenn procedure after being deemed unsuitable candidates for Fontan completion are not small in number, and may develop arterio-venous (AV) pulmonary malformations during the follow-up period. We present the case of a 17-year-old woman with severe systemic desaturation 13 years after Glenn procedure and repair of total anomalous pulmonary venous return. Among other anomalies, the patient disclosed hemiazygos continuation to a persistent left superior vena cava. This case supports the concept that returning flow from the abdominal vein plays an important role in the well-balanced growth of the pulmonary artery and in the inhibition of the pulmonary AV malformation.

Symptomatic interrupted inferior vena cava: report of a case presenting with haematochezia

Interrupted inferior vena cava (IVC) is a rare developmental defect. IVC interruption is usually accompanied with azygos and hemiazygos continuation, and is asymptomatic. Here, we report the imaging findings of a patient with an interrupted IVC with diffuse collaterals between the infrarenal IVC and large renal veins, left gonadal, and perirectal haemorrhoidal-portal collateral veins with associated haematochezia. Depending on the haemodynamic changes, interrupted IVC may cause possible different clinical findings as presented here.

Cathéter de chambre implantable : un curieux trajet

We report a clinical case of a persistent left superior vena cava discovered in a 50-year-old female patient when a port-a-cath was inserted. This already seldom malformation was associated with an arteria lusoria and polysplenia with left inferior vena cava with hemiazygos continuation, right-sided stomach, short pancreas, preduodenal portal vein and intestinal malrotation, but without any cardiac abnormalities.

Left-sided or transposed inferior vena cava ascending as hemiazygos vein and draining into the coronary sinus via persistent left superior vena cava: case report

Left persistent superior vena cava occurs in ∼0.3% of the general population and 4.3% in patients with congenital heart disease. Left-sided inferior vena cava has been well-described and occurs in ∼0.2–0.5% of the general population. In most cases left inferior vena cava crosses over to the right via the left renal vein or more inferiorly and crossover is usually anterior but rarely posterior to the aorta [ [1] Dahnert W. 2nd ed. Radiology review manual. Williams and Wilkins, Baltimore1996: 433 Google Scholar ]. Entire transposition of the inferior vena cava to the left with hemiazygos continuation is extremely rare although it has been previously described [ [2] Brickner M.E. Eichhorn E.J. Netto D. et al. Left-sided inferior vena cava draining into the coronary sinus via persistent left superior vena cava: case report and review of the literature. Catheter Cardiovasc Diagn. 1990; 20: 189-192 Crossref PubMed Scopus (25) Google Scholar ]. We report a case of a left-sided (transposed) inferior vena cava communicating with the hemiazygos vein which is draining into the dilated coronary sinus via persistent left superior vena cava.

Angiographic findings of persistent primitive hepatic venous plexus with underdevelopment of the infrahepatic inferior vena cava in pediatric patients.

We describe the angiographic diagnosis and significance of persistence of the primitive hepatic venous plexus with underdevelopment of the infrahepatic inferior vena cava. We recommend that inferior venacavography be performed in routine assessment before surgery of patients with azygos or hemiazygos continuation of the inferior vena cava, in whom redirection of systemic venous blood to the pulmonary artery is contemplated.

Infrahepatic Interruption of the Inferior Vena Cava with Azygos Continuation: A Potential Mimicker of Aortic Pathology

Infrahepatic interruption of the inferior vena cava (IVC) with azygos or hemiazygos continuation is a rare finding. In this anatomic entity, the intrahepatic segment of the IVC is absent, and the hepatic veins empty directly into the right atrium. Venous blood flow from the lower body is directed from the IVC into the azygos system at the level of the renal veins, with resultant dilation of the azygos and/or hemiazygos veins. Because these enlarged vessels lie parallel to the descending thoracic aorta, they may be mistaken for aortic pathology (dissection, aneurysm, or rupture) during transesophageal echocardiography (TEE). We describe a case of azygos continuation of the IVC initially misdiagnosed by TEE as partial aortic rupture. Repeat TEE with intravenous agitated saline injection correctly identified the condition, and the echocardiographic features are described. (J Am Soc Echocardiogr 1998;11:1078-83.)

Prospective angiographic study of the abnormalities of systemic venous connections in congenital and acquired heart disease

Angiographic definition of systemic venous connections was obtained prospectively in 780 consecutive patients with congenital heart disease and 102 patients with acquired valvular heart disease undergoing cardiac catheterization. Attempts were made to enter the innominate vein and perform a balloon occlusion angiogram in each patient. In patients with congenital heart disease, bilateral superior vena cava were present in 32/771 patients (approximately 4%) with levocardia and 3/9 patients with dextrocardia. Among patients with bilateral superior vena cava (n = 35), an innominate vein of variable size that could be entered was present in six patients. Small tributaries connecting the right and left superior vena cava were found and entered in six patients. The superior vena cava was entered via its connection to morphologic left atrium in five patients and via the coronary sinus in 17 patients. Abnormalities of the inferior vena cava were seen in 7/780 patients. The following abnormalities of the inferior vena cava were noted: azygous continuation of rightsided inferior vena cava in levocardia -- 3 patients, hemiazygos continuation of the leftsided inferior vena cava in levocardia -- 1 patient, azygos continuation of the leftsided inferior vena cava in dextrocardia -- 1 patient, interruption of inferior vena cava below the liver with a plexus of veins joining the azygos vein -- 1 patient, and an inferior vena cava draining into the leftward aspect of the common atrium -- 1 patient. Abnormalities of the systemic venous connections were seen in 2/102 patients with acquired heart disease: bilateral superior vena cava in 1 patient and bilateral inferior vena cava in 1 patient. Abnormalities of systemic venous connections were seen in approximately 5% patients with congenital heart disease and approximately 2% patients with acquired heart disease. Small tributaries or an innominate vein of variable size often connect left and right superior vena. Contrast material can be injected into these connections to document the presence of bilateral superior vena cava.

Bidirectional Glenn Shunt for Complex Cyanotic Congenital Heart Disease

The bidirectional Glenn Shunt has been advocated for definitive or staged palliation of patients with a functional single ventricle and decreased pulmonary blood flow who are unsuitable for a Fontan operation. Between April 1990 and July 1994, 86 patients underwent bidirectional Glenn operation at the All India Institute of Medical Sciences in New Delhi. This operation was performed electively in 73 patients (group I), as a take-down for Fontan failure in 10 patients (group II), and to complement a two-ventricle repair in 3 patients in whom the right ventricle or the tricuspid valve was inadequate to handle the entire systemic venous return (group III). Fifty-five other procedures were performed in addition to the cavopulmonary shunt. The mean ICU stay was 2 days. There were 5 early deaths in group I, 6 in group II, and none in group III. Mean oxygen saturation at the time of discharge was 84.2% on room air. Follow-up ranged from 3 to 51 months. The bidirectional Glenn shunt was definitive palliation in 9 patients with azygos or hemiazygos continuation of the inferior vena cava. In the remaining patients, a corrective procedure is planned only if there is evidence of failure of palliation or ideal criteria for the Fontan procedure are met. Only 3 patients from group I have therefore undergone subsequent conversion to a Fontan circulation. The bidirectional Glenn shunt provides excellent relief of cyanosis, does not volume load the heart, and possibly lowers the risk of a subsequent Fontan operation. Timely take-down of a failed Fontan procedure is imperative for successful salvage.

Unsuspected Infrahepatic Interruption of Inferior Vena Cava Associated With Floppy Mitral Valve, Mitral Valve Prolapse, and Severe Mitral Regurgitation

We describe a case of unsuspected infrahepatic interruption of the inferior vena cava with hemiazygos continuation in a 67-year-old man presenting with chest pain and evidence of mitral regurgitation. He had no persistent superior vena cava, with the hemiazygos draining directly into the right superior vena cava. Polysplenia and severe mitral prolapse were also present: the latter may represent more than an incidental finding in this condition. This malformation may deserve consideration in adults undergoing femoral right heart catheterization. Chest radiographic studies are the basic clue to the diagnosis.