Rare case of pulmonary arteriovenous fistula simulating residual defect after transcatheter closure of patent foramen ovale for recurrent paradoxical embolism

Abstract

We report on a patient suffering from recurrent cerebrovascular events despite previous transcatheter closure of persistent foramen ovale (PFO) with a Helex occluder. There was evidence of persistent left-to-right atrial shunt shown by transesophageal contrast echocardiography and the patient was admitted to our institution for interventional closure of the supposed residual defect. However, the PFO was completely closed by the device and left pulmonary artery injections showed a pulmonary arteriovenous fistula in the left lower lobe. This rare malformation may well explain the recurrent paradoxical embolism. Transcatheter fistula closure with coils was performed successfully. This case underlines that the existence of an isolated pulmonary arteriovenous fistula as a right-to-left shunt in patients with cryptogenic stroke should not be overlooked, even if a PFO is present and pulmonary arteriovenous fistula is not suggested by the initial physical findings or chest X-ray.

Potential Faces of Patent Foramen Ovale (PFO PFO)

“…This was associated with progressive hypoxemia as well as an increase in pulmonary artery pressure with exercise. Combination of elevation in pulmonary artery pressure with exercise, severe R to L shunting at peak exercise, and hypoxemia may suggest that this patient may have had a combination of PFO and pulmonary arteriovenous fistula as has been reported previously, 44,45 however a CT angiogram did not show a pulmonary arteriovenous fistula in our patient.…”

Postoperative pulmonary arteriovenous fistula resulting in recurrent cryptogenic stroke

“…This case clearly demonstrates that a pulmonary arteriovenous fistula should always be taken into account in patients with cryptogenic stroke, even if a PFO is present [1]. Contrast echocardiography [2] hereby is an extremely useful tool for diagnosis.…”

Stroke in a patient with pulmonary arteriovenous fistula: A case report study

“…reported recurrent ischemic strokes after a successful surgical closure of patent foramen ovale, which led them to the diagnosis of an underlying isolated PAVF. [7] Our patient was diagnosed with PAVF 13 years ago and surgical repair was performed, however, bubble study showed that the fistula was still open.…”