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.