Acute stroke, catheter related venous thrombosis, and paradoxical cerebral embolism: report of two cases.

BACKGROUND: Patent foramen ovale (PFO) has been associated with cryptogenic stroke, particularly in young adults. However, the source of particles leading to cerebral embolism remains frequently unknown despite comprehensive evaluation.

OBJECTIVE: To report and comment on therapeutic options for 2 patients with acute ischemic strokes, PFO, and venous access related thrombosis, sources of paradoxical embolism, from Boston Medical Center stroke database.

CASE DESCRIPTIONS: Case 1. A 71-year-old man presented with brain magnetic resonance imaging (MRI) confirmed acute cerebellar infarction. Echocardiography showed a PFO and thrombotic material at the tip of a peripherally inserted central catheter (PICC) line in the superior vena cava (SVC) prolapsing into the right atrium (RA). Case 2. A 64-year-old woman with end-stage renal disease and PFO presented with brain MRI confirmed acute parietal lobe infarction. Three days prior to her stroke, she had thrombectomy and venoplasty of an arterio-venous (AV) dialysis graft followed by a post-thrombectomy fistulogram that showed persistent thrombotic material at the venous site.

CONCLUSIONS: PFO associated with large venous access site thrombosis was the most likely mechanism of stroke in both cases. Local thrombosis at sites of large venous access may be an overlooked source of paradoxical embolism in patients with PFO as well as a preventable cause of stroke in critically ill patients.