BACKGROUND: Mediastinal venous malformation (MVM) and fusiform superior vena cava aneurysm (F-SVCA) are both rare congenital vascular anomalies.
METHODS: A 46-year-old male presented with acute ischemic stroke of unknown etiology. Computed tomography (CT) angiography revealed the coexistence of MVM and F-SVCA. Diagnostic venography demonstrated a significant reduction in blood flow velocity within the F-SVCA, but failed to identify a direct connection to the left heart system or pulmonary vein. The patient expired due to extensive brain damage caused by a stroke.
CONCLUSIONS: This case may increase the necessity of meticulous radiological evaluation and preventive management for these anomalies, as mediastinal vascular anomalies can result in thromboembolic complications.

Polysplenia syndrome is an embryological disorder whereby the usual left-right asymmetry of thoracic and abdominal viscera fails to develop. It is a rare entity, estimated to occur at a frequency of 1 in 40,000, and is often associated with cardiac and biliary abnormalities. More than 75% of patients die before the age of 5 years, and even in the absence of cardiac anomalies, only 5%-10% of patients are expected to survive into adulthood without complications. Although polysplenia syndrome encompasses a wide range of anatomic abnormalities, there is no single pathognomonic feature. Hence, the prognosis of patients with polysplenia depends on their anatomy, thus necessitating radiology in their management. Here we present a case of a 56-year-old man with polysplenia syndrome and situs inversus totalis. This presentation is atypical because polysplenia is usually considered a form of situs ambiguus, and cases with situs inversus totalis are exceedingly rare. Also noted in our patient are variations in the great vessels, including aortic arch branches and the venae cavae which are features not typically associated with either polysplenia syndrome or situs inversus totalis. The patient is healthy and asymptomatic at baseline, with his diagnosis being made incidentally. Our case report is the first to describe this unique combination of cardiothoracic and cardiovascular anatomy. It also emphasizes the importance of radiologists in caring for patients with laterality defects. As these disorders are uncommon, more data on their anatomic variations may help provide better medical care to this patient population.

A simple and robust method for veno-venous extracorporeal membrane oxygenation (V-V ECMO) involves a drainage cannula into the inferior vena cava via the femoral vein (FV) and a reinfusion cannula into the right atrium (RA) via the internal jugular vein (IJV) (F-J configuration). However, with this method, the arterial oxygen (PaO2) is said to remain below 100 mmHg.Since recently, in our ICU, to prevent drainage failure, we apply a modification from the commonly practiced F-J configuration by advancing the tip of the drainage cannula inserted via the FV into the superior vena cava (SVC) and crossing the reinfusion cannula inserted via the IJV in the RA (F(SVC)-J(RA) configuration). We experienced that this modification can be associated with unexpectedly high PaO2 values, which here we investigated in detail.Veno-arteriovenous ECMO was induced in a 65-year-old male patient who suffered from repeated cardiac arrest due to acute respiratory distress syndrome. His chest X-ray images showed white-out after lung rest setting, consistent with near-absence of self-lung ventilation. Cardiac function recovered and the system was converted to F(SVC)-J(RA) configuration, after which both PaO2 and partial pressure of pulmonary arterial oxygen values remained high above 200 mmHg. Transesophageal echocardiography could not detect right-to-left shunt, and more efficient drainage of the native venous return flow compared to common F-J configuration may explain the increased PaO2.Although the F(SVC)-J(RA) configuration is a small modification of the F-J configuration, it seems to provide a revolutionary improvement in the ECMO field by combining robustness/simplicity with high PaO2 values.

BACKGROUND: Venovenous extracorporeal membrane oxygenation (V-V ECMO) has become an important treatment for severe pneumonia, but there are various complications during the treatment. This article describes a case with severe pneumonia successfully treated by V-V ECMO, but during treatment, the retrovenous catheter, which was supposed to be in the right internal vein, entered the superior vena cava directly in the mediastinum. The ECMO was safely withdrawn after multidisciplinary consultation. Our experience with this case is expected to provide a reference for colleagues who will encounter similar situations.
METHODS: A 64-year-old man had severe pulmonary infection and respiratory failure. He was admitted to our hospital and was given ventilation support (fraction of inspired oxygen 100%). The respiratory failure was not improved and he was treated by V-V ECMO, during which the venous return catheter, which was supposed to be in the right internal vein, entered the superior vena cava directly in the mediastinum. There was a risk of massive mediastinal bleeding if the catheter was removed directly when the ECMO was withdrawn. Finally, the patient underwent vena cava angiography + balloon attachment + ECMO withdrawal in the operating room (prepared for conversion to thoracotomy for vascular exploration and repair at any time during surgery) after multidisciplinary consultation. ECMO was safely withdrawn, and the patient recovered and was discharged.
CONCLUSIONS: Patients may have different vascular conditions. Multidisciplinary cooperation can ensure patient safety. Our experience will provide a reference for similar cases.

Imaging the superior vena cava (SVC) during two-dimensional (2D) transthoracic echocardiographic examination is challenging and should be performed routinely. Here, we present a case where a lower (juxta-atrial) SVC mass was seen prolapsing into the right atrium by 2D transthoracic echocardiography; in this case, the imaging of the lower (juxta-atrial) SVC was done from the subcostal window. It was not possible to image the SVC from the suprasternal, right supraclavicular, left parasternal, or apical windows. CT scan of the chest with intravenous contrast was done in this case and showed an anterior mediastinal mass invading the SVC and prolapsing into the right atrium. CT-guided biopsy proved the mass to be a type B2 thymoma.

BACKGROUND: Superior vena cava (SVC) aneurysms are a relatively uncommon disease that has not been widely reported. The conventional surgical approach for treating SVC aneurysms includes open thoracotomy and mid-sternotomy. However, in this case, the aneurysm could be safely resected by thoracoscopic simultaneous lateral and subxiphoid access methods.
METHODS: A 58-year-old male presented with intermittent chest pain and persistent discomfort in the chest area. A chest computed tomography scan revealed a 6.2 cm aneurysm in the left innominate vein and SVC junction. For surgical resection, simultaneous lateral and subxiphoid access were planned to achieve optimal proximal and distal aneurysm control. The approach site was 1 cm below the xiphoid process, the fifth mid-axillary line and the seventh anterior axillary line on the right side. The aneurysm was resected using a stapler. The patient was discharged on the third day after chest tube removal on the second postoperative day with no particular issues.
CONCLUSIONS: Aneurysms located within the mediastinum can be accessed through thoracoscopic approach without open surgery and safely resected using vascular staples.

Coronary artery fistulas (CAFs) are rare congenital coronary artery abnormalities, with direct communication between a coronary artery and a cardiac chamber, great vessel or other structure. We report here, a rare case of a 25-year-old male with CAF from the aneurysmal left main coronary artery to the superior vena cava detected on echocardiography and computerized tomography (CT) coronary angiography.

Superior vena cava (SVC) stenosis is rarely caused by iatrogenic trauma. Herein, the case of a 5-year-old boy who underwent radiofrequency ablation for paroxysmal supraventricular tachycardia but developed SVC stenosis and related syndromes is reported. Notably, the child exhibited an enlarged left atrial appendage that had partially breached the pericardium. Subsequent interventions involved successful removal of the stenosis, artificial vascular reconstruction, and comprehensive radiofrequency ablation of the entire right atrium, along with ligation of the left atrial appendage under direct vision. As a result, the child experienced relief from symptoms.

Paroxysmal atrial fibrillation originates most commonly in the pulmonary veins. However, the superior vena cava has proved to be arrhythmogenic in some cases. Pulsed field ablation, an emerging ablation technology, selectively affects myocardial tissue. Herein, we present a case of paroxysmal atrial fibrillation in a 64-year-old man who was admitted to our hospital for pulsed field ablation. The tachycardia was recurrent despite four successful pulmonary vein isolations. The superior vena cava was determined to be involved in arrhythmogenesis. The atrial fibrillation terminated immediately after the pulsed field ablation discharge at the superior vena cava.

We report a case of atrial fibrillation (AF) recurrence after pulmonary vein isolation, which patient had AF trigger in the superior vena cava (SVC) near the sinus node (SN). The ultra-high-resolution mapping revealed that SN located within the SVC and the atrial activation from the SN to SVC propagated in both septal and lateral direction, then upward with circumventing the spontaneous conduction block identified just above and lateral SN (upper hemisphere). We successfully isolated SVC including the ectopic origin at the same level as the SN by utilizing the spontaneous conduction block line around the SN without any complication.