Paradoxical embolism following thromboaspiration of an arteriovenous fistula thrombosis: a case report

Abstract

IntroductionParadoxical embolism is an increasingly reported cause of arterial embolism. Several embolic sources have been described, but thrombosis of an arteriovenous fistula as a paradoxical emboligenic source has not, to the best of our knowledge, been reported.Case presentationA 50-year-old Caucasian woman received a renal graft for primary hyperoxaluria. After transplantation, she was maintained on daily hemodialysis. Thrombosis of her arteriovenous fistula occurred two weeks post-transplantation and was treated by thromboaspiration, which was partially successful. During a hemodialysis session immediately following thromboaspiration, she developed a coma with tetraplegia requiring intensive cardiorespiratory resuscitation. Brain magnetic resonance imaging revealed various hyperdense areas in the vertebrobasilar territory resulting from bilateral occlusion of posterior cerebral arteries. Transesophageal echocardiographic examination showed a patent foramen ovale, while pulse echography of the arteriovenous fistula revealed the persistence of extensive clots that were probably the embolic source. A paradoxical embolus through a patent foramen ovale was suggested because of the proximity of the neurological event to the thrombectomy procedure.ConclusionsThe risk of paradoxical embolism in a hemodialyzed patient with a patent foramen ovale deserves consideration and requires careful evaluation in situations of arteriovenous fistula thrombosis.

Paradoxical Embolus following Percutaneous Thrombectomy of Hemodialysis Reliable Outflow Graft

“…While the common complications of interventions to treat stenotic or thrombotic lesions compromising vascular dialysis access are well described, this case demonstrates an infrequent but very serious cause of potential morbidity and mortality (3, 4). Although cases of cerebral ischemia due to paradoxical embolism in the setting of a PFO have been reported following dialysis access interventions, these are exceedingly rare (5–––8). To the best of our knowledge, there has never been a report of such an event in a patient with the extensive and well-characterized central venous stenosis as seen in this individual, or in a patient with a HeRO graft prosthesis.…”

“…These complications vary in frequency and severity, with some of the more well-known being hemorrhage, vessel rupture, and pulmonary embolism, any of which can range in severity from life-threatening to subclinical (2––4). An infrequently described but potentially devastating complication of these procedures is a cerebrovascular accident (CVA) due to paradoxical embolization in the setting of a patent foramen ovale (PFO) (5–––8).…”

Primary Hyperoxaluria: A Sri Lankan Case Series

“…First patient showed extensive bone involvement due to oxalosis (Figure 1 & 2), which resulted in severe bone pain and radiological changes. Additionally she had fistula issues with recurrent thrombosis and hemorrhage from puncture sites, which is a known vascular complication [5]. She was unfortunate to miss the diagnosis presenting with high normal 24 hour oxalate excretion-at her presentation and then to receive a renal transplant, only to see it failing rapidly.…”

A case of pulmonary thromboembolism with synchronous and metachronous paradoxical embolism through the patent foramen ovale - a case report

“…Incidence paradoxní embolie je relativně nízká -přibližně kolem 2 % všech tepenných embolizací [1,2]. Cílem paradoxní embolizace může být jakákoli terminální část tepenného řečiště, ale nejčastěji je postižen mozek (až v 55 % případů) a končetiny (až 40 % případů) [3,4]. Je známo, že až u 40 % cerebrovaskulárních tromboembolických příhod není identifikován zdroj embolu (v anglo saské literatuře jsou označovány jako "cryptogenic strokes"), a otázkou zůstává, jak velké zastoupení v těchto případech mají právě paradoxní embolizace [5,6].…”

“…Při rozboru pravolevých zkratů bylo zjištěno, že PFO je jejich příčinou přibližně v 95 %, ve 4 % jde o plicní arteriovenózní píštěle, 1 % tvoří defekty mezisíňové přepážky [9]. Dalšími zdroji paradoxní embolie mohou být defekty komorového septa, kasuisticky byla popsána paradoxní embolizace z parciálně trombózovaného AV shuntu [3] a z perzistující levostranné horní duté žíly ústící do levé horní plicní žíly [10].…”