Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Abstract

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Keywords: Endoscopic ultrasound; Vascular intervention; Esophageal varices; Gastric varices; Portal vein; Therapeutic endoscopy

Core Tip: Endoscopic ultrasound (EUS) technology has evolved rapidly in clinical practice, first as merely a diagnostic tool and now a therapeutic modality. EUS-guided interventions involve combining real-time imaging capability with invasive therapeutic interventions. The gastrointestinal (GI) tract has proximity to various vascular structures in the abdomen and mediastinum and thus provides a unique window to access these structures with EUS to render EUS-guided vascular interventions. Herein, this article provides an overview of EUS-guided vascular interventions for GI bleeding, portal vein access, and therapeutic implications, tumor diagnosis, and access to non-GI structures.