Abstract 1870: Pathophysiology of Chronic Venous Insufficiency in the Adult With a Fontan Circulation
INTRODUCTION: Chronic venous insufficiency (CVI) is prevalent in adults with a Fontan circulation, however the pathophysiology is unknown. We defined the prevalence of venous reflux and obstruction, potential etiologies of CVI, and assessed the hypothesis that venous reflux correlates with clinical CVI in a Fontan circulation.
METHODS: Fifty-one adult Fontan subjects from the Congenital Heart Disease in Adults Lower Extremity Systemic Venous Health in Fontan Patients study, and twenty age and gender matched control subjects (ten without cardiac disease; ten with repaired tetralogy of Fallot) underwent lower extremity Doppler venous ultrasound. We investigated 510 venous segments for obstruction (lack of venous compressibility) and reflux (lasting ≥ 1 second in proximal deep veins and ≥ 0.5 seconds in superficial and calf veins).
RESULTS: The prevalence of venous reflux (Figure A⇓: negative B: positive) was significantly greater in the Fontan population compared to healthy controls (51% vs. 10%, p = 0.03.). There was no venous obstruction suggestive of deep vein thrombosis in any patient. Venous reflux was more prevalent than clinical CVI: forty-nine percent of Fontan subjects with venous reflux demonstrated no clinical signs of venous disease. Predictors of venous reflux in multivariate analysis were single right ventricle (p= 0.033) and use of anti-arrhythmic medications (p= 0.044), as well as family history of venous disease (p= 0.003).
CONCLUSIONS: Venous reflux is highly prevalent and venous obstruction is notably absent in adults with a Fontan circulation. Clinical CVI underestimates pathophysiologic venous insufficiency in adults with a Fontan circulation.