For a tracheoesophageal fistula, what are the indications for using through‑the‑scope clips versus helix‑tacking devices?

Endoscopic Management of Tracheoesophageal Fistula: Clips vs Helix Tacking

For tracheoesophageal fistulas, through-the-scope clips (TTSCs) and endosuturing alone are usually not effective; therefore, placement of a fully covered stent providing a snug fit is the primary recommendation, with over-the-scope clips (OTSCs) reserved for adjunctive closure attempts. 1

Primary Treatment Algorithm

First-Line Approach: Fully Covered Stent

• Stenting is the mainstay for tracheoesophageal fistulas because clips and suturing devices alone typically fail to achieve durable closure 1
• The stent must provide a snug fit with diameter slightly wider than the natural esophageal diameter to seal the fistula without expanding the defect
• Proximal stent fixation is mandatory using either endosuturing or a stent-fixing device, as there is no stricture to anchor the stent 1

Role of Clips in TEF Management

Over-the-Scope Clips (OTSCs):

• Effective for defects 1-2 cm in size with 85.3% clinical success rate 1
• Failure occurs with defects >2 cm or closure attempts >72 hours after perforation 1
• Can be used as adjunctive therapy with stenting for complex fistulas 2
• Requires endoscope withdrawal and reinsertion with device mounted (tip diameter increases to 16.5-21 mm) 1

Through-the-Scope Clips (TTSCs):

• Not recommended as monotherapy for established TEF 1
• May be used for small mucosal perforations during procedures (e.g., POEM) but inadequate for true fistulas 1

Helix Tacking System (X-Tack)

Indications for helix tacking:

• Large or irregular-shaped defects that cannot be closed with standard clips 1
• Situations where endoscope withdrawal is problematic (e.g., right colon, tortuous anatomy) 1
• Adjunctive closure with other devices for complex fistulas 3
• Achieves 77.2% complete closure alone, 95.2% with adjunctive clips 4

Advantages over traditional clips:

• Deployed through standard gastroscopes/colonoscopes without endoscope withdrawal 1
• Allows closure of defects averaging 34.3 mm 4
• Can be deployed in Z-shape pattern to approximate fibrotic edges 3

Clinical Decision Framework

For Fresh Post-Operative TEF (Within Days):

1. Attempt primary closure with TTSCs, OTSCs, or endosuturing
2. Always add fully covered stent regardless of clip placement success 1

For Established TEF:

1. Primary: Fully covered stent with proximal fixation 1
2. Consider OTSC if defect <2 cm and <72 hours old 1
3. Consider helix tacking for irregular defects or when endoscope withdrawal is problematic 1, 4, 3

For Complex/Large TEF:

1. Bridging tracheal stent placement to cover fistula 2
2. Definitive closure with OTSC after stabilization 2
3. Helix tacking with anchor-pronged clips for enhanced tissue grasping 3

Critical Pitfalls to Avoid

• Never rely on TTSCs or endosuturing alone for established TEF—failure is expected 1
• Do not place esophageal stents without proximal fixation—high migration rates without stricture to anchor 1
• Avoid OTSC attempts if defect >2 cm or >72 hours old—success rates plummet 1
• Do not use oversized stents—this expands rather than seals the defect 1
• For cervical esophagus with prior surgery/radiation, use caution with OTSC due to non-smooth cap edges 1

Alternative/Adjunctive Therapies

Endoscopic vacuum therapy:

• 90% healing rate for anastomotic leaks, 96% for perforations 1
• Consider for large or persistent fistulas not amenable to clips or stents
• Median therapy duration 17 days 1

Adverse event rate for helix tacking system: 5.4% 4