, according to a practice update from the American Gastroenterological Association.
The AGA Institute’s Clinical Practice Update on interventional EUS, published in Clinical Gastroenterology and Hepatology, makes the case for broader adoption of two clinically available interventions – EUS-guided coil injection therapy of gastric varices and EUS-guided portosystemic pressure gradient measurement – while listing key research questions that remain to be answered. The update also describes current evidence for several emerging EUS interventions.
Dr. Marvin Ryou
The update’s authors, led by Marvin Ryou, MD, of Brigham and Women’s Hospital, Boston, advised, when available, EUS-guided coil injection therapy of gastric varices over conventional direct endoscopic injection with cyanoacrylate glue, noting that EUS guidance “enhances the precision of injection,” expands treatment options to include placement of hemostatic coils, and uses Doppler to provide real-time feedback on hemostasis.
Available evidence suggests that EUS-guided gastric variceal therapy is “safe, with excellent acute hemostasis and low re-bleeding rates, and likely superiority over traditional direct endoscopic glue injection,” Dr. Ryou and colleagues wrote in their update. Nonetheless, they cautioned, “the development of a consensus technique would be helpful,” better training of technicians is needed, and large, multicenter studies comparing EUS with standard interventional radiology approaches are still needed.
EUS-guided direct measurement of the portosystemic pressure gradient (PPG) may offer improved clinical efficiency over a percutaneous endovascular approach, Dr. Ryou and colleagues determined, notably when there is concern for a pre-sinusoidal cause of portal hypertension. The EUS intervention allows for the “concurrent ability to perform esophagogastroduodenoscopy and EUS as a one-stop shop during which PPG, liver biopsy, and endoscopic features of portal hypertension … can all be evaluated, obtained, and potentially treated during a single procedure.”
The authors updated guidelines on four emerging interventions for which evidence remains limited: EUS-guided injection therapy of rectal varices, EUS-guided splenic artery embolization, EUS-guided injection therapy in patients with splenic artery pseudoaneurysms, and EUS-guided portal vein sampling. While the last of these interventions appears safe, the authors cautioned, it should be performed only as part of a research protocol.
The authors described one experimental intervention, an EUS-guided intrahepatic portosystemic shunt, in which a self-expanding metal stent can be deployed via EUS to bridge the hepatic and portal vein and decompress a hypertensive portal system. The intervention, an alternative to interventional radiology approaches, has been tried only in the animal model.
Dr. Ryou and his colleagues cautioned that their guideline was not the product of a formal systematic review, “but rather is based on a literature review to provide practical advice.”
As a general rule, they said, EUS-guided vascular interventions should be considered when the vascular target occurs in or near the gastrointestinal wall, “which may confer an advantage to an endoscopic rather than percutaneous access,” and when the intervention has “a clinical efficacy and safety profile comparable, if not superior, to current alternatives.” All the interventions described in the guideline satisfy the first condition, the authors said, but have yet to meet the second.
Dr. Ryou and two of his three coauthors disclosed financial relationships, including consulting fees and research support, from device manufacturers.
