title: Embolization of Veno-venous Collaterals after the Fontan Operation Is Associated with Decreased Survival.
abstract: OBJECTIVE
  After Fontan operation, hemodynamically significant veno-venous collateral (VVC) vessels can lead to systemic arterial desaturation. Outcomes after embolization of VVCs have not been determined. We sought to determine the frequency of and outcomes for patients undergoing VVCs embolization after Fontan operation.
  
  
  METHODS
  We retrospectively analyzed clinical and hemodynamic data of patients who underwent cardiac catheterization after the Fontan operation from 1995 to 2014 at Mayo Clinic. Clinical, imaging, and hemodynamic data from patients with VVCs were compared based on intervention (embolization) vs. nonintervention.
  
  
  RESULTS
  Four hundred ninety-six patients with prior Fontan operation had catheterization; 109 VVCs were identified in 72 patients (37 males, mean age 26 ± 12 years). Embolization was performed in 31/72 patients (43%). Following embolization, no improvement was demonstrated in oxygen saturation or hemoglobin concentration at ambulatory follow-up (2.5 ± 2 years), and cardiac index declined at follow-up catheterization (5.6 ± 3 years). Overall, 15 patients (21%) died at a mean of 2.8 ± 4 years after embolization. Fifty percent of deaths after embolization occurred in patients with Fontan pressures ≥18 mm Hg. Five-year survival of patients with VVCs undergoing embolization was 74% compared with 92% in those patients who did not undergo embolization (P < .01). In multivariate analysis, significant predictors of death on follow-up were embolization [hazard ratio (HR) = 9.3 (95% confidence interval [CI], 2.8-42), P = .0001], atrio-pulmonary Fontan (HR = 4.2 [95% CI, 1.4-15], P = .01), and heterotaxy (HR = 3.7 [95% CI, 1.0-15], P = .05).
  
  
  CONCLUSIONS
  We observed decreased 5-year survival in patients who had VVC embolization. Embolization of VVC in patients after Fontan should be evaluated very carefully in patients with atrio-pulmonary type Fontan, heterotaxy, and those with Fontan pressure above 18 mm Hg. These patients may benefit from the "natural" fenestration that VVCs provide.
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Poterucha
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Jonathan N
authors.initials: JN
authors.lastname: Johnson
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Nathan W
authors.initials: NW
authors.lastname: Taggart
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Allison K
authors.initials: AK
authors.lastname: Cabalka
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.|Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Hagler
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.|Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Driscoll
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.|Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minn, USA.
authors.forename: Frank
authors.initials: F
authors.lastname: Cetta
mesh_terms: D000328:Adult; D003097:Collateral Circulation; D004621:Embolization, Therapeutic / Q000009:adverse effects / Q000401:mortality; D005260:Female; D018729:Fontan Procedure / Q000009:adverse effects / Q000401:mortality; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: Adult Congenital Heart Disease; Embolization; Fontan; Veno-venous Collaterals