Pulmonary Arteriovenous Fistulae After Fontan Operation: Incidence, Clinical Characteristics, and Impact on All-Cause Mortality

Hideo Ohuchi; Aki Mori; Michikazu Nakai; Kazuto Fujimoto; Toru Iwasa; Heima Sakaguchi; Kenichi Kurosaki; Isao Shiraishi

doi:10.3389/fped.2022.713219

Pulmonary Arteriovenous Fistulae After Fontan Operation: Incidence, Clinical Characteristics, and Impact on All-Cause Mortality

Front Pediatr. 2022 Jun 9:10:713219. doi: 10.3389/fped.2022.713219. eCollection 2022.

Authors

Hideo Ohuchi^{1

2}, Aki Mori¹, Michikazu Nakai³, Kazuto Fujimoto¹, Toru Iwasa¹, Heima Sakaguchi¹, Kenichi Kurosaki¹, Isao Shiraishi¹

Affiliations

¹ Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Suita, Japan.
² Adult Congenital Heart Disease, National Cerebral and Cardiovascular Center, Suita, Japan.
³ Department of Medical and Health Information Management, National Cerebral and Cardiovascular Center, Suita, Japan.

Abstract

Background: The Fontan operation is a surgical procedure used in children with univentricular hearts. Pulmonary arteriovenous fistulae (PAVF) is a major complication after a Fontan operation. However, the incidence and related clinical pathophysiology of PAVF remain unclear.

Purpose: This study aimed to clarify the incidence of PAVF, its clinical characteristics, and its influence on all-cause mortality.

Methods and results: We serially assessed the presence of PAVF using pulmonary artery angiography and/or contrast echocardiography during catheterization in 391 consecutive patients who underwent the Fontan procedure and compared the results with the Fontan pathophysiology and all-cause mortality. PAVF developed in 36 patients (9.2%), including 30 diffuse- and six discrete-PAVF types. The PAVF-free rates at 1, 5, 10, 15, 20, and ≥25 years after Fontan operation were 97, 96, 93, 88, 87, and 83%, respectively. The mean arterial blood oxygen saturation (SaO₂) in patients with diffuse PAVF at each corresponding postoperative stage were 90, 91, 91, 91, 89, and 88%, respectively, indicating lower SaO₂ levels than those in patients without PAVF (all p < 0.01). However, there was no difference in the SaO₂ levels between patients with discrete PAVF and those without PAVF. During a median follow-up period of 2.9 years after the last catheterization, 31 patients, including 12 patients with PAVF, died. Patients with PAVF, especially those with diffuse PAVF, had a higher mortality rate (p = 0.01) than those without PAVF (hazard ratio: 3.6, 95% confidence interval: 1.6-7.8, p = 0.0026).

Conclusion: Patients who underwent Fontan surgery had an increased incidence of PAVF as they aged. Discrete PAVF did not influence SaO₂ or mortality, whereas the presence of diffuse PAVF caused hypoxia and was associated with all-cause mortality.

Keywords: Fontan operation; arterial oxygen saturation; heart failure; mortality; pulmonary arteriovenous fistulae.