Multimodality imaging approach to paradoxical embolism: a cauliflower mass on the Eustachian valve

摘要

The Eustachian valve was first described by Bartolomeo Eustachio (Italian anatomist) in 1552. It is an embryolog-ical remnant of the inferior vena cava valve that prena-tally directs the oxygenated blood from inferior vena cava across the patent foramen ovale (PP'O) into systemic circulation. Generally, following birth, after the closure of the foramen ovale it gradually regresses and does not have a specific function, but it may persist in some patients as a floating membrane in the right atrium (RA), a nonpathological functionless structure.1 The prevalence of the Eustachian valve in the normal population is unknown. Generally, it is an incidental finding without any significant pathophysiological consequences, but in some particular cases, unfortunately, it can become the site of thrombus formation and paradoxical embolic source.1 In our case report we describe a particular case of paradoxical systemic embolism due to a giant cauliflower thrombus on the Eustachian valve, which caused ischemic stroke, pulmonary embolism and splenic infarction. A 50-year-old female patient, without cardiovascular risk factors, presented to the emergency department of our hospital with 3 h of blurred vision, Broca’s aphasia, motor deficits (weakness) and reading disability. On admission, laboratory exam showed moderate anemia (hemoglobin = 9.4 g/dl)，mild increase in inflammation markers (G-reactive protein = 1.63 mg/dl) and otherwise nothing relevant. A brain computed tomography (GT) scan was performed based on the patient^ clinical symptoms showing a faded area of focal hypodensity of the cortico-subcortical cerebral white matter, in the left temporo-parietal area. Afterwards，MRI of the brain was performed showing the presence of hyperintense signal alterations in long repetition time sequences, likely expression of polydistrictual embolic phenomena. The angio-MRI study, performed upon completion documented regular patency of the vertebral and carotid arteries and vases of the Willis polygon. The patient was therefore transferred to the stroke unit, with diagnosis of ischemic stroke. ECG on admission was normal and continuous rhythm monitoring did not reveal any arrhythmia. At second day of hospitalization, progressive dyspnea, chest pain, tachycardia and mild hypoxemia suddenly started. On suspicion of pulmonary embolism a chest CT angiography was performed. GT images showed filling defects of the arteriosus branch afferent to the postero-basal segment of the right lower lobe confirming the diagnosis of pulmonary embolism. Finally, at abdomen CT multiple splenic infarcts and no perisplenic effusion were found. As an incidental finding, a huge mass in the RA was seen during CT scan, needing further investigations. Thus, as first line test, we performed a transthoracic echocardiogram that showed a huge and mobile isoechogenic mass in the RA (Fig. la). However, to better define the dimension, origin and connections with other structures a transesophageal echocardiogram (TOE) was mandatory. TOE, performed under mild sedation, displayed a voluminous cauliflower-shaped moving mass in the RA (approximately 25 mm x 30 mm), adherent to the Eustachian valve.