What is the suitability and protocol for a patient with a history of Fontan procedure and protein-losing enteropathy for the Fontan Intervention with Gore (FIGR) procedure, a catheter-based intervention?

FIGR Procedure for Fontan Patients with Protein-Losing Enteropathy

Critical Assessment: FIGR is NOT Mentioned in Current Guidelines

The Fontan Intervention with Gore (FIGR) procedure is not referenced in current ACC/AHA guidelines or available evidence for managing Fontan patients with protein-losing enteropathy. The guidelines instead focus on traditional catheter-based fenestration creation, surgical revision, and medical management 1.

Standard Catheter-Based Interventions for PLE in Fontan Patients

Transcatheter Fenestration Creation

• Transcatheter fenestration to create an interatrial communication has been used to treat PLE after Fontan operation, but results are often disappointing 2.
• Fenestration creation showed reduction of ascites and edema in only 9 of 16 procedures (56%), with 63% of fenestrations spontaneously occluding 2.
• Even after "successful" fenestration, resolution of PLE may be incomplete and recurrences occurred in all patients in one series 2.
• Survivors with PLE more frequently received fenestration creation (48% of cases) compared to non-survivors 3.

Pre-Intervention Hemodynamic Assessment Requirements

Cardiac catheterization must be performed at regional centers with ACHD expertise before any Fontan intervention (Class I recommendation) 1.

Critical hemodynamic parameters to assess include:

• Fontan pathway pressure (mean >15 mmHg indicates major hemodynamic disturbance and decreased survival) 4, 3.
• Pulmonary vascular resistance (survivors averaged 2.1 ± 1.1 Wood units vs. 3.8 ± 1.6 WU in non-survivors) 3.
• Cardiac index (survivors averaged 2.7 ± 0.7 L/min/m² vs. 1.6 ± 0.4 L/min/m² in non-survivors) 3.
• Ventricular end-diastolic pressure (>15 mmHg indicates major hemodynamic disturbance) 4.
• Systemic ventricular function (ejection fraction <55% associated with decreased survival) 3.

Anatomic Factors Requiring Identification

• Any degree of obstruction in the nonpulsatile Fontan circuit is hemodynamically significant 4.
• Fontan pathway stenosis is significantly associated with PLE development (p = 0.001-0.48) 5.
• Absence of a fenestration is significantly associated with PLE development 5.
• Relief of Fontan obstruction was used more frequently in survivors (23% of cases) 3.

Suitability Criteria Based on Evidence

Favorable Hemodynamic Profile

• Mean Fontan pressure ≤15 mmHg 3.
• Pulmonary vascular resistance <3 Wood units 3.
• Preserved ventricular function (EF ≥55%) 3.
• Cardiac index >2.0 L/min/m² 3.

Unfavorable Profile Requiring Alternative Management

• High Fontan pressure (mean >15 mmHg), decreased ventricular function (EF <55%), and NYHA class >2 at diagnosis are associated with decreased survival 3.
• These patients should receive early consideration for cardiac transplantation (Class IIa recommendation) 1.

Alternative Management Strategies

Medical Therapy

Multimodal medical therapy should be initiated, as combined treatment was associated with improved outcomes 5.

Specific regimens used more frequently in survivors:

• Spironolactone (used in 68% of survivors) 3.
• Pulmonary vasodilators (sildenafil used in 19% of survivors; can improve exercise capacity) 1, 3.
• Budesonide (systemic anti-inflammatory therapy; combination with pulmonary vasodilators associated with improved survival in unadjusted analysis) 5.
• Octreotide (used in 21% of survivors) 3.

Surgical Options

Fontan revision surgery is reasonable for patients with atriopulmonary Fontan connections with recurrent arrhythmias, preserved systolic function, and severe atrial dilation (Class IIa recommendation) 1.

Cardiac Transplantation

Evaluation for cardiac transplantation is reasonable in adults with Fontan palliation and signs and symptoms of protein-losing enteropathy (Class IIa recommendation) 1.

• PLE is associated with 10-year transplant-free survival of only 65.7% compared to 97.3% without PLE 6.
• Early consideration should be given to Fontan takedown or cardiac transplantation in severely symptomatic patients who do not respond to fenestration 2.

Critical Pitfalls

• Transcatheter fenestration may be only a bridge to definitive procedure, not a cure 2.
• Maintaining fenestration patency is difficult with high spontaneous occlusion rates 2.
• PLE remains difficult to treat despite advances, with substantial long-term mortality 5.
• Practice variation is common, and comprehensive assessment with individual treatment strategies is mandatory 5.