Diagnosis and therapy for pulmonary arteriovenous fistula in patients with presumed patent foramen ovale

Abstract

An increasing number of patients are being referred for PFO closure for prevention of recurrent paradoxical embolism. Diagnosis is usually made using hand agitated echo bubble contrast with transthoracic or transesophageal echo. It is inevitable that some of these patients will have pulmonary arteriovenous fistulae (PAVF), either with or without associated PFO, which may be the sole cause of paradoxical embolism, or remain after PFO closure as a source of continued embolization. Intravenous contrast echo for the diagnosis of PFO is both insensitive and nonspecific. We describe a method to diagnose and localize PAVF during a catheterization procedure using intracardiac echo in conjunction with selective injection of bubble contrast into the pulmonary arteries. This allows for the rapid and accurate diagnosis of PAVF when a PFO is not found and for the exclusion of associated PAVF when PFO exists.