Systemic-to-pulmonary venous shunt in superior vena cava obstruction: depiction on computed tomography venography

Acquired Systemic-to-pulmonary Venous Shunt or Persistent Left Superior Vena Cava? A Rare Right-to-left Shunt Case-based Discussion

Cardiac shunts are often described in congenital or pediatric populations, but systemic-to-pulmonary venous shunts in adult patients are reported in literature in isolated case reports. We present the case of a 70-year-old female with a left superior vena cava (SVC) draining into the left atrium by the left superior pulmonary vein, with a complete right-to-left shunt of the superior venous circulation caused by a former catheter thrombosis in the right SVC. Diagnosis was suspected after a contrast echocardiography showing an exclusive perfusion of left heart after intravenous injection and confirmed by helical computed tomography with three-dimensional reconstruction. After medico-surgical discussion, a first-line conservative treatment with oxygen therapy was chosen, due to the stability of symptoms and high predicted risk of perioperative mortality. The particularities of this case are that we cannot determine if the origin of this shunt is a latent persistent left SVC becoming symptomatic after the SVC obstruction or an abnormal collateral pathway due to the thrombosis and the unusual indirect communication through a pulmonary vein.

Hypoxemia and Right-to-Left-Shunt in Patient with Antiphospholipid Syndrome: A Case Report with Multimodality Imaging Findings and Literature Review

This is a case report of an extremely rare cause of superior vena cava syndrome with systemic-to-pulmonary venous shunts, illustrated using different imaging modalities with successful SVC and IVC dilatation and stenting.

Systemic-to-pulmonary venous shunt in a patient with non-Hodgkin lymphoma: A case report and review of the literature

We describe a case of a systemic-to-pulmonary venous shunt secondary to superior vena cava obstruction in a patient with newly diagnosed non-Hodgkin lymphoma. This rare condition manifested with symptoms of dyspnea and hypoxemia that were out of proportion to the pleural effusion diagnosed on chest imaging. Standard treatment of such rare collateral plexuses is observation. However, it is important for clinicians to be cognizant that in rare cases such plexuses can lead to right-to-left shunt complications such as embolism.

Superior vena cava syndrome associated with right-to-left shunt through systemic-to-pulmonary venous collaterals

Superior vena cava (SVC) obstruction is associated with the gradual development of venous collaterals. We present a rare form of systemic-to-pulmonary subpleural collateral pathway that developed in the bridging subpleural pulmonary veins in a 54-year-old woman with complete SVC obstruction. This uncommon collateral pathway represents a rare form of acquired right-to-left shunt due to previous pleural adhesions with an increased risk of stroke due to right-to-left venous shunting, which requires lifelong anticoagulation.

Oncologic emergencies

OBJECTIVES

To provide an up-to-date review of current literature on the pathophysiology, diagnosis, and management of five key malignancy-related complications: superior vena cava syndrome, malignant pericardial effusion, malignant spinal cord compression, hypercalcemia, and acute tumor lysis syndrome.

DATA SOURCES

Database searches and review of relevant medical literature.

DATA SYNTHESIS

Malignancy-related complications demand increased attention from intensivists due to their frequency and increasing cancer prevalence. Although such complications portend a poor prognosis, proper acute management can improve short-term outcomes by facilitating either definitive care of the underlying malignancy or the institution of appropriate palliative measures.

CONCLUSIONS

Knowledge of malignancy-induced complications in critically ill patients expedites the ability of the intensivist to properly manage them. Five complications commonly requiring emergency management are addressed in this review. Specifically, superior vena cava syndrome may warrant radiation, chemotherapy, vascular stenting, or surgical resection. Malignant pericardial effusion may require emergency pericardiocentesis if cardiac tamponade develops. Malignant spinal cord compression demands immediate spinal imaging, glucocorticoids, and either surgery or radiation. Hypercalcemia requires aggressive intravenous hydration and a bisphosphonate. Acute tumor lysis syndrome necessitates intravenous hydration, rasburicase, and management of associated electrolyte abnormalities.

Embolization of a symptomatic systemic to pulmonary (right-to-left) venous shunt caused by fibrosing mediastinitis and superior vena caval occlusion

Paradoxical embolization can occur when a right-to-left shunt allows a venous thromboembolus to escape filtration by the lungs. Venous collateral pathways draining into the left heart incited by superior vena cava obstruction are a rare acquired right-to-left shunt. Herein, the authors report on a case of transient ischemic attack in a patient with vena caval occlusion secondary to histoplasmosis-related fibrosing mediastinitis, with subclavian vein thrombosis and a right-to-left extracardiac shunt diagnosed with echocardiography. Despite the complexity of the collateral network, this shunt was successfully eradicated with coil embolization.