LAMS for EUS-guided drainage of pancreatic fluid collections

Lumen-apposing metal stents (LAMS) have emerged as a highly effective tool for endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs), such as pseudocysts and walled-off necrosis. This systematic review and meta-analysis evaluated three commonly used types of LAMS: Axios, Nagi, and Spaxus, focusing on their efficacy, safety, and clinical performance.

Key Findings:

Technical Success:

All three LAMS demonstrated exceptional technical success rates:

• Axios: 97.7%
• Nagi: 96.9%
• Spaxus: 98.2%

This indicates that the placement of the stents is highly reliable across all types.

Clinical Success:

Clinical success rates, which reflect effective resolution of the pancreatic fluid collections, were also strong:

• Axios: 90.9%
• Nagi: 88.5%
• Spaxus: 93.5%

This highlights that all three stents are effective in achieving the desired therapeutic outcomes.

Adverse Events (AEs):

Safety profiles varied significantly among the stents.

• Axios: Highest rate of total adverse events (20.4%).
• Nagi: Moderate rate of adverse events (13.8%).
• Spaxus: Lowest rate of adverse events (7.6%).

Bleeding:

Bleeding complications were an important safety consideration, with rates differing across stent types:

• Axios: Highest bleeding rate (7.0%).
• Nagi: Moderate bleeding rate (3.8%).
• Spaxus: Lowest bleeding rate (1.8%).

Moderate-to-severe bleeding occurred across all stent types but was notably less frequent with Spaxus.

Stent Migration:

Stent migration was another safety concern:

• Axios: Rare (2.8%).
• Nagi: Most common (7.8%).
• Spaxus: Least common (0.9%).

Need for Endoscopic Necrosectomy:

The need for additional procedures, such as endoscopic necrosectomy to remove necrotic debris, differed significantly:

• Axios: Highest necrosectomy requirement (54.5%).
• Nagi: Lower requirement (16%).
• Spaxus: Comparable to Nagi (19.9%).

Impact of PFC Type:

• Patients with walled-off necrosis experienced more frequent adverse events compared to those with pseudocysts. This reflects the complexity and severity of walled-off necrosis compared to simpler pseudocysts.

Overall Assessment:

While all three LAMS options provide excellent efficacy for draining pancreatic fluid collections, their safety profiles differ meaningfully. The Spaxus stent demonstrated the most favorable balance of high success rates and low complications, including minimal bleeding, stent migration, and adverse events. However, the choice of stent may depend on patient-specific factors, the type of PFC (pseudocyst vs. walled-off necrosis), and procedural considerations.

Clinical Implications:

• Axios may be preferred for cases where high clinical success is paramount, although its higher rates of adverse events and bleeding should be considered.
• Nagi offers a moderate safety profile but has a higher risk of stent migration.
• Spaxus stands out for its excellent safety profile, making it a strong choice for minimizing complications while maintaining high efficacy.

In conclusion, LAMS are a transformative advancement in the management of pancreatic fluid collections, offering minimally invasive, highly effective treatment options with differences in safety outcomes that warrant careful consideration.