Balónová koronární angioplastika u závažných biliárních striktur: nový endoskopický přístup

Súhrn

Závažné striktury žlučových cest představují značnou výzvu při endoskopických zákrocích a často jsou rezistentní na konvenční dilatační techniky. Tato série případů zkoumá úspěšné využití balónků pro koronární angioplastiku, které jsou obvykle vyhrazeny pro kardiovaskulární aplikace, u šesti pacientů s těsnými biliárními strikturami, u nichž selhaly standardní balónky pro through-the-scope (TTS). Pacienti, od dětí až po dospělé, měli různou etiologii, včetně striktur po transplantaci a chronických zánětlivých striktur. Výsledky prokázaly všestrannost a účinnost koronárních balónků, díky nimž bylo dosaženo kompletního obnovení průtoku žlučí bez komplikací. Tato studie zdůrazňuje potenciál koronární balónkové angioplastiky jako nepostradatelného nástroje při komplexních výkonech endoskopické retrográdní cholangiopankreatografie (ERCP). Tato zjištění podporují širší využití této techniky a opravňují k dalšímu zkoumání prostřednictvím rozsáhlejších klinických studií.

Klíčová slova:

ERCP – koronární balónek – biliární stenting – závažné biliární striktury – endoskopická dilatace – série případů

Introduction

The utilization of coronary balloons for severe biliary strictures has emerged as a viable alternative in managing challenging cases, particularly when traditional methods fail. Recent studies highlight the effectiveness of various balloon types, including modified angioplasty and cardiac angioplasty balloons, in achieving successful dilation of strictures, leading to improved patient outcomes.

Building on this foundation, severe biliary strictures continue to challenge clinical practice, particularly during endoscopic retrograde cholangiopancreatography (ERCP). Conventional through--the-scope (TTS) biliary balloons, while effective for routine cases, frequently fail in tight or tortuous strictures. These limitations necessitate innovative alternatives.

Coronary angioplasty balloons, initially designed for vascular interventions, are increasingly recognized for their potential in navigating narrow, resistant biliary strictures. Their smaller diameter and high-pressure capabilities uniquely position them to overcome the challenges posed by tight strictures, making them particularly suitable in cases where traditional dilation fails [1–6].

This case series aims to evaluate the safety, feasibility, and clinical efficacy of coronary balloon angioplasty in patients with severe biliary strictures, highlighting its role as a viable alternative when standard approaches fail.

Case series

Patient demographics and clinical context

This study included six patients (five males and one female) aged 4 to 62 years (mean age 36.8 years), presenting with severe biliary strictures. The etiologies included chronic pancreatitis, post-liver transplantation strictures, primary sclerosing cholangitis (PSC), and complex pediatric cases. Although this case series includes a limited number of patients, it represents a diverse cohort with varying etiologies, providing insight into potential applications of this technique.

Detailed demographics are as follows:

• patient 1: 50-year-old male with chronic pancreatitis;
• patient 2: 62-year-old male with PSC and suspected cholangiocarcinoma;
• patient 3: 43-year-old male with post -⁠ -orthotopic liver transplantation (OLT) anastomotic stricture;
• patient 4: 4-year-old female with a post-partial OLT stricture;
• patient 5: 10-year-old male with hilar and common bile duct (CBD) strictures;
• patient 6: 52-year-old male with post -⁠ -OLT anastomotic stricture.

 

Procedural overview

All patients underwent ERCP under general anesthesia with anesthesiologist supervision. Coronary balloons (3–4 mm diameters) were employed when TTS biliary balloons (6–8 mm) failed to achieve adequate dilation. Following successful dilation, biliary stents were deployed to ensure long-term patency.

 

Individual cases:

• patient 1: a tight pancreatic duct stricture was managed with a 3 -⁠ mm coronary balloon, followed by a 6-Fr pigtail stent;
• patient 2: proximal hepatic duct dilation was achieved with a 4 -⁠ mm coronary balloon, enabling brushing for cytology and nasobiliary drainage;
• patient 3: a post-OLT stricture was dilated using a 3 -⁠ mm coronary balloon, allowing the placement of a 10 -⁠ mm Kaffes stent;
• patient 4: sequential dilation with coronary and TTS balloons enabled dual plastic stent deployment in this pediatric patient;
• patient 5: three separate hilar and CBD strictures were navigated with coronary balloons, followed by straight plastic stent placement;
• patient 6: an anastomotic stricture post-OLT was effectively dilated using a coronary balloon, facilitating subsequent TTS balloon use and stenting.

 

Results

Utilization of coronary balloons resulted in 100% technical success, with complete restoration of bile flow in all six patients. Follow-up imaging at intervals of three to six months confirmed sustained biliary patency without significant complications. Notably, no procedure-related adverse events, such as perforation or hemorrhage, were reported.

Tab. 1 summarizes the key findings, including pre-procedure characteristics, interventions, and outcomes.

 

Discussion

Coronary balloons, originally designed for cardiac interventions, have shown significant promise in the management of severe biliary strictures, particularly in cases where traditional ERCP tools are ineffective, such as primary sclerosing cholangitis (PSC). By utilizing small-caliber cardiac angioplasty balloons, these strictures can be effectively dilated, offering a novel and practical solution for challenging cases.

 

Mechanisms and clinical outcomes

Coronary balloons can alleviate severe biliary strictures through several mechanisms, primarily involving dilation and restoration of biliary flow. These balloons, originally designed for cardiac applications, have been adapted for endoscopic and percutaneous interventions in biliary strictures, demonstrating significant efficacy in various clinical scenarios.

 

Advantages of coronary balloons

technical versatility: applicable across a wide range of stricture etiologies, including pediatric and complex post--surgical cases;

high efficacy: achieved dilation in 100% of cases in this series;

safety: no major complications were observed, even in high-risk patients.

Comparison with alternative techniques

While coronary balloons demonstrate unique advantages in managing tight biliary strictures, alternative techniques have also been explored. For instance, wire-guided diathermic dilators and ultra-slim metallic stents have shown success in managing severe malignant biliary strictures, particularly in patients with altered anatomy. Additionally, cutting balloons have been utilized as a rescue therapy for benign bilioenteric anastomotic strictures that are refractory to conventional balloon dilation, further underscoring the versatility of balloon--based interventions in biliary strictures.

However, the smaller diameter and high-pressure capabilities of coronary balloons make them uniquely suitable for cases where other methods fail, particularly in pediatric patients and tight anastomotic strictures, as highlighted in this case series.

Future directions

While the findings are promising, this case series is limited by its small sample size. Larger, multi-center studies are essential to validate these outcomes and explore long-term efficacy. Additionally, cost-effectiveness analyses could further support their integration into standard clinical practice. Studies have reported high technical success rates with minimal complications when using balloon dilation techniques, including coronary balloons, for biliary strictures. These methods have shown effectiveness in both benign and malignant cases, with reduced recurrence rates. However, it is essential to consider the specific clinical context, patient anatomy, and availability of specialized equipment. Further research and clinical trials are necessary to establish standardized protocols and assess the long-term efficacy and safety of these innovative techniques.

Conclusion

Coronary angioplasty balloons represent a valuable addition to the endoscopic armamentarium for managing severe biliary strictures. Their success in this case series demonstrates their potential to address limitations of conventional methods, particularly in challenging or refractory cases. These findings pave the way for broader adoption and further research into their role in complex endoscopic procedures. These results emphasize the need for continued innovation and exploration of coronary balloon applications in diverse biliary scenarios.