Microcatheter embolization of lower gastrointestinal hemorrhage: an old idea whose time has come

Special considerations in the management of lower GI bleed by interventional radiology

Despite the rapid development of diagnostic and therapeutic modalities and techniques to manage LGIB patients from interventional radiology's standpoint, a successful localization of the bleeding site that leads to an effective embolotherapy remains a significant technical challenge. The interventional radiologist's decisions when managing patients with LGIB may significantly impact the clinical outcomes; therefore, management should be made based on careful and thorough considerations of factors such as etiology, locations, patient's comorbidities, and potential post-procedure complications, among others. The purpose of this paper is to review the management of LGIB by interventional radiology, focusing on a few challenging and common clinical situations that require special consideration by interventional radiologists.

Endovascular Treatment for Acute Thromboembolic Occlusion of the Superior Mesenteric Artery and the Outcome Comparison between Endovascular and Open Surgical Treatments: A Retrospective Study

We reported our experience with endovascular treatment for patients with acute thromboembolic occlusion of the superior mesenteric artery (ATOS) as well as comparing the efficacy between endovascular and traditional open surgical treatments. Eighteen consecutive patients with ATOS who received endovascular treatment and 12 patients who received open surgical treatment between February 2007 and October 2012 at Tianjin Union Medical Center (Tianjin, China) were retrospectively reviewed. Primary clinical outcomes included the technical success, requirement of laparotomy, length of bowel resection, perioperative mortality within 30 days, and surgical complications. The patients were followed up for 0.1 to 98 months. For patients who underwent endovascular treatment, complete technical success was achieved in 8 (44.4%) patients and partial success was achieved in the remaining 10 (55.6%) patients. Laparotomy was required in 6 (33.3%) patients. The 30-day mortality was 16.7%. In comparison to open surgical therapy, endovascular therapy achieved lower requirement of laparotomy (in 33.3% versus in 58.3% of cases, p = 0.18), significantly shorter average length of bowel resection (88 ± 44 versus 253 ± 103 cm, p = 0.01), and lower mortality rate (16.7% versus 33.3%, p = 0.68). The endovascular therapy is a promising treatment alternative for ATOS.

Long-term results of microcoil embolization for colonic haemorrhage: how common is rebleeding?

OBJECTIVE

To determine the long-term results of patients undergoing transcatheter coil embolization for the treatment of acute colonic haemorrhage.

METHODS

Patients undergoing angiography for suspected colonic bleeding between January 2002 and December 2012 were reviewed (average age, 60 years; 38.4% male). Baseline, procedural and outcome parameters were recorded following the Society of Interventional Radiology guidelines. Primary outcome measures included early (<30 days) and delayed (>30 days) rebleeding events and adverse procedure-related complication. Average follow-up time was 996 days (median, 232 days; range, 30-3663 days).

RESULTS

One or multiple sites of bleeding were identified in 40 cases. Coil embolization was performed in 39 patients, 26 (66.7%, 26/39) of whom were treated successfully without technical/clinical failure (n = 12) or loss to follow-up (n = 1). Three patients (11.5%, 3/26) rebled in the early period within 30 days; one patient went on to hemicolectomy. Four patients (15.3%, 4/26) experienced delayed rebleeding after 30 days; two of whom also underwent hemicolectomy. No major complication occurred. One minor complication of short segment arterial dissection was seen in the clinical failure group. One case of asymptomatic ischaemia was identified on a patient undergoing pre-operative colonoscopy for elective bowel resection. No instances of ischaemic stricture were seen. All-cause mortality of successfully treated and all patients at 1 year was 31% (8/26) and 30% (12/40), respectively.

CONCLUSION

Transcatheter coil embolization is a durable treatment option with a technical and clinical success rate of 67% in the setting of acute colonic haemorrhage. A modest level of rebleeding was seen among successfully treated patients in both the early and delayed periods; in the majority of patients, embolization proved to be definitive therapy.

ADVANCES IN KNOWLEDGE

Transcatheter coil embolization is a durable and potentially definitive therapy in the management of acute colonic haemorrhage.

A case-based approach to common embolization agents used in vascular interventional radiology

OBJECTIVE

The objective of this article is to familiarize the reader with the most commonly used embolic agents in interventional radiology and discuss an approach for selecting among the different embolic agents. This article reviews their properties and uses a case-based approach to explain how to select one.

CONCLUSION

A wide variety of embolic agents are available. Familiarity with the available embolic agents and selection of the most appropriate embolic agent is critical in interventional radiology to achieve optimum therapeutic response and avoid undesired, potentially disastrous complications such as nontarget embolization.

Selective arterial embolization with ethylene-vinyl alcohol copolymer for control of massive lower gastrointestinal bleeding: feasibility and initial experience

PURPOSE

To evaluate the efficacy, safety, and clinical outcomes of superselective embolization using ethylene-vinyl alcohol copolymer (Onyx Liquid Embolic System; ev3 Neurovascular, Irvine, California) as the primary treatment for acute and massive lower gastrointestinal bleeding (LGIB).

MATERIALS AND METHODS

Between January 2008 and October 2013, all patients with focal massive LGIB who were treated by embolization were retrospectively analyzed. The study was approved by the hospital's ethics committee; informed consent was obtained in all cases. Onyx was chosen as the embolic agent in all cases in an intention-to-treat fashion. Embolization was indicated in 31 consecutive patients (mean age, 80 y ± 11.1). Multidetector computed tomography and digital subtraction angiography were performed in all patients.

RESULTS

Active bleeding was detected in all cases. A colonoscopy was performed in 11 patients. The correlation between multidetector computed tomography and angiography findings was 96.7%. The causes of bleeding were diverticula in 15 patients, iatrogenic in 7 patients, neoplasia in 3 patients, hemorrhoids in 2 patients, angiodysplasia in 2 patients, and unknown in 2 patients. Embolization was not possible in one patient, who required urgent left hemicolectomy. The technical success rate was 93.5%. The embolic material refluxed in one patient, causing an undesired embolization, without any clinical consequences. In the 30 patients who received embolization, the immediate bleeding control rate was 100%. Rebleeding at 30 days occurred in three patients (10%). There were no major complications, intestinal ischemia, or deaths attributable to the treatment. No patient needed surgery or new embolization during a mean follow-up period of 23.7 months (range, 1-71 mo).

CONCLUSIONS

Control of massive LGIB using superselective embolization with Onyx is feasible and safe.

Safety and efficacy of transcatheter arterial embolization for lower gastrointestinal bleeding: a single-center experience with 112 patients

PURPOSE

To assess the safety and efficacy of transcatheter arterial embolization for lower gastrointestinal bleeding (LGIB) and to determine the prognostic factors that affect clinical outcome.

MATERIALS AND METHODS

All patients diagnosed with LGIB by angiography at a single institution from April 2006 to January 2013 were included in a retrospective study. The rates of technical success, early recurrent bleeding, major complications, clinical success, and in-hospital mortality for transcatheter arterial embolization were determined. The influence of possible prognostic factors on the outcome was analyzed.

RESULTS

A total of 112 patients were included (36 with small-bowel LGIB, 36 with colon LGIB, and 40 with rectal LGIB). N-butyl cyanoacrylate (NBCA) was the embolic agent for 84 patients (75.0%), whereas gelatin sponge pledgets (n = 20), microcoils (n = 2), polyvinyl alcohol particles with adjunctive gelatin sponge pledgets (n = 1), and blood clots (n = 1) were used in the other patients. The technical success rate was 96.4%. For the entire group, the rates of early recurrent bleeding, major complications, clinical success, and in-hospital mortality were 17.4%, 4.6%, 74.5%, and 25.0%, respectively. These were 15.2%, 4.8%, 75.3%, and 26.2%, respectively, in the NBCA group. Hematologic malignancy, immobilization status, and coagulopathy were significant prognostic factors for clinical outcomes.

CONCLUSIONS

Transcatheter arterial embolization is a safe and effective treatment for LGIB. NBCA could be used as a primary embolic agent for this procedure.

Early endovascular treatment of superior mesenteric occlusion secondary to thromboemboli

OBJECTIVE

To evaluate our early experience with endovascular revascularization in patients with acute thromboembolic occlusion of the superior mesenteric artery (SMA).

METHODS

A retrospective review was conducted of all patients who underwent endovascular revascularization for acute thromboembolic SMA occlusion from May 2005 to May 2012. Endovascular revascularization was performed using aspiration, intra-arterial thrombolysis, and adjunctive stent-placement techniques. Laparotomy was performed if the patient developed clinical signs of advanced bowel ischemia after endovascular procedure.

RESULTS

Twenty-one patients underwent endovascular revascularization for acute thromboembolic SMA occlusion. All presented with acute-onset abdominal pain. Three patients had rebound tenderness before the procedure. Computed tomography angiography revealed complete occlusion in seven cases and incomplete occlusion in 14 cases, with no evidence of free gas or bowel necrosis. The median duration from onset of symptoms to revascularization was 8.7 ± 4.1 hours (range, 2-18 hours). Completely successful endovascular revascularization occurred in six cases (aspiration alone, 3 cases; combined aspiration and urokinase, 3 cases); partial success was achieved in 15 cases (aspiration alone, 4 cases; combined aspiration and urokinase, 10 cases; and combined aspiration, urokinase, and stent placement, 1 case). Laparotomy was required in five patients, all of whom had SMA main trunk complete occlusion and required small bowel resection. The 30-day mortality for all patients was 9.5%. During a median follow-up of 26 months, 15 patients remained asymptomatic, three patients reported occasional abdominal pain, and one patient had temporary short-bowel syndrome.

CONCLUSIONS

Percutaneous revascularization is a promising alternative to surgery for acute SMA occlusion in selected patients who have no signs of advanced bowel ischemia. Early diagnosis followed by prompt endovascular intervention with close postprocedural monitoring is key. Laparotomy is indicated in patients who develop new or worsening signs of peritonism after endovascular procedure, particularly in those who had complete occlusion of the main trunk of the SMA.

Revisiting the past: intra-arterial vasopressin for severe gastrointestinal bleeding in Crohn's disease

Technological advances in the last couple of decades have led to a tremendous improvement in the safety and efficacy of embolization making it the therapeutic intervention of choice in angiogram positive lower gastrointestinal bleeding. Vasopressin has thus been forgotten and it is hardly ever used by the current generation of interventionists. However, coil embolization is technically challenging and requires greater expertise. Difficulty in super-selective catheterization and lack of adequate collateralization can also prevent successful delivery of coils. In this article we present the successful use of intra-arterial vasopressin in a patient with Crohn's disease with severe lower gastrointestinal bleeding. Despite not being the first choice, vasopressin can be safely and effectively used in selected patients who are not candidates for embolotherapy. The purpose of this article is to discuss the relative merits and demerits of vasopressin vis-à-vis embolization and to identify the role of vasopressin in the current era of super-selective embolization. Successful control of massive lower gastrointestinal bleeding by intra-arterial vasopressin infusion has previously been reported only once before in Crohn's disease. We suggest that this technique may be used in an attempt to avoid surgery in these patients.

Primary percutaneous aspiration and thrombolysis for the treatment of acute embolic superior mesenteric artery occlusion

OBJECTIVES

To evaluate technical success rate and clinical outcome of patients with acute embolic superior mesenteric artery (SMA) occlusion who were treated with primary percutaneous revascularization.

METHODS

At three medical centers the radiological information system databases were used to identify all patients in whom primary percutaneous revascularization for the treatment of acute embolic SMA occlusion was attempted between 2001 and 2010. Percutaneous treatment was performed in 15 patients (median age 80 years, range 49-88 years). These patients represent the study population. Eleven patients reported abdominal pain. Five patients exhibited peritoneal signs. Revascularization was defined as complete technical success if (1) patency of the SMA with residual stenosis of not more than 30% in diameter and (2) sufficient perfusion of the entire bowel were obtained.

RESULTS

Complete technical success was achieved in eleven patients. After percutaneous revascularization laparotomy was performed in six patients and in three of them bowel resection was carried out (length of resected segments 20-80 cm). The 30-day mortality was 33% (five of 15 patients). None of the surviving patients exhibited short-bowel syndrome.

CONCLUSIONS

Primary percutaneous aspiration and thrombolysis constitutes a promising alternative to surgical revascularization in selected patients with acute embolic SMA occlusion.

Selective angiographic diagnosis and transcatheter arterial embolization of iatrogenic massive upper gastrointestinal bleeding

AIM: To study the clinical value of angiography and transcatheter arterial embolization (TAE) for the iatrogenic upper gastrointestinal hemorrhage.

METHODS: Thirty seven cases with iatrogenic hemorrhage in the upper digestive tract received emergency selective angiography. According to the interval from bleeding onset to angiographic time, patients were divided into two groups, that is, the emergency group (n = 28 cases) and non-emergency group (n = 9 cases). According to find out positions and causes of bleeding during angiography, all patients underwent arterial embolization with different embolic agents.

RESULTS: DSA revealed positive result in 33 cases of 37cases with a total positive rate of 89.2% (33/37). The positive rate for the emergency group was 96.4% (27/28) and 66.7%(6/9) for non-emergency group. Positive rate of angiography was significantly higher in emergency group than in non-emergency group (P < 0.05). Arterial embolization was successfully carried out in 31 positive cases; 2 severe pancreatitis cases rebled 1 week after embolization and was treated successfully with re-embolization. One severe pancreatitis case had no bleeding, but died of multi-organ function failure 13 days later. Of four cases with negative angiography who undertook trial embolizing therapy, bleeding ceased in 3 cases; 1 case who failed bleeding was given surgery to stop bleeding. During the 3-12 month-follow-up, there were no relapse or complications.

CONCLUSION: Emergency selective angiography improves positive rate and plays an important role in detecting the sites of iatrogenic upper gastrointestinal massive bleeding. Selective arterial embolization is a safe and effective hemostatic measure.

Obscure gastrointestinal bleeding: preoperative CT-guided percutaneous needle localization of the bleeding small bowel segment

A 57-year-old woman presented with obscure gastrointestinal bleeding. Double balloon enteroscopy, angiography, and surgery including intraoperative enteroscopy failed to identify the bleeding site. Multidetector computed tomography (CT) depicted active bleeding of a small bowel segment. The bleeding segment was localized by CT-guided percutaneous needle insertion and subsequently removed surgically.

Surgical treatment concepts for acute lower gastrointestinal bleeding

BACKGROUND AND PURPOSE

To this day, the diagnostic and therapeutic strategy for acute lower gastrointestinal hemorrhage requiring transfusion varies among different hospitals. The purpose of this paper was to evaluate our own data on the group of patients presented and to outline our diagnostic and therapeutic regime taking into account the literature of the past 30 years.

METHODS

Following prospective data collection on 63 patients of a university hospital (40 male, 23 female patients) who received surgical intervention for acute lower intestinal hemorrhage requiring transfusion, we retrospectively analyzed the data. After a medical history had been taken, all patients underwent clinical examination, including digital palpation; 62 patients underwent procto-rectoscopy, 38 gastroscopy and colonoscopy, 52 patients colonoscopy only, and 45 patients gastroscopy only. Angiography was applied in 14 cases and scintigraphy in 20 cases.

RESULTS

Diagnostic procedures to localize hemorrhage were successful in 61 cases, 41 of which through endoscopy, 12 through angiography, and eight through scintigraphy. Of our group of patients, 32 suffered from a bleeding colonic diverticulum, eight from angiodysplasia, and five from bleeding small bowel diverticula. Five patients had inflammatory bowel disease and three neoplasia. Among the surgical interventions, segmental resections were performed most frequently (15 sigmoidectomies, 11 small bowel segmental resections, 11 left hemicolectomies, seven right hemicolectomies, one proctectomy). Subtotal colectomies were carried out in ten cases. The complication rate for this group of critically ill, negatively selected patients was 60.3% and the mortality rate was 15.9%.

CONCLUSIONS

Examination and stabilization of the patient is directly followed by diagnostic localization. Today, we primarily rely on nonsurgical control of hemorrhage by endoscopy or angiography; the indication for surgery is mainly limited to peracute, uncontrollable, and recurrent forms. In the case of surgery, intestinal segmental resection is recommended after identification of the lesion; if the localization of colonic hemorrhage is uncertain, subtotal resection is the method of choice. For stable patients with unverifiable small-bowel hemorrhage we recommend regular re-evaluation.

Noninvasive evaluation of active lower gastrointestinal bleeding: comparison between contrast-enhanced MDCT and 99mTc-labeled RBC scintigraphy

OBJECTIVE

The purpose of our study was to compare contrast-enhanced MDCT and (99m)Tc-labeled RBC scanning for the evaluation of active lower gastrointestinal bleeding.

SUBJECTS AND METHODS

Over 17 months, 55 patients (32 men, 23 women; age range, 21-92 years) were evaluated prospectively with contrast-enhanced MDCT using 100 mL of iopromide 300 mg I/mL. Technetium-99m-labeled RBC scans were obtained on 41 of 55 patients and select patients underwent angiography for attempted embolization. Each imaging technique was reviewed in a blinded fashion for sensitivity for detection of active bleeding as well as the active lower gastrointestinal bleeding location.

RESULTS

Findings were positive on both examinations in eight patients and negative on both examinations in 20 patients. Findings were positive on contrast-enhanced MDCT and negative on (99m)Tc-labeled RBC in two patients; findings were negative on contrast-enhanced MDCT and positive on (99m)Tc-labeled RBC in 11 patients. Statistics showed significant disagreement, with simple agreement = 68.3%, kappa = 0.341, and p = 0.014. Sixteen of 60 (26.7%) contrast-enhanced MDCT scans were positive prospectively, with all accurately localizing the site of bleeding and identification of the underlying lesion in eight of 16 (50%). Nineteen of 41 (46.3%) (99m)Tc-labeled RBC scans were positive. Eighteen of 41 matched patients went on to angiography. In four of these 18 (22.2%) patients, the site of bleeding was confirmed by angiography, but in 14 of 18 (77.8%), the findings were negative.

CONCLUSION

Contrast-enhanced MDCT and (99m)Tc-labeled RBC scanning show significant disagreement for evaluation of active lower gastrointestinal bleeding. Contrast-enhanced MDCT appears effective for detection and localization in cases of active lower gastrointestinal bleeding in which hemorrhage is active at the time of CT.

Experimental study on acute ischemic small bowel changes induced by superselective embolization of superior mesenteric artery branches with N-butyl cyanoacrylate

PURPOSE

To evaluate the degree of ischemic changes of the small bowel after superselective embolization of superior mesenteric artery (SMA) branches at the vasa recta level with N-butyl cyanoacrylate (NBCA) in dogs.

MATERIALS AND METHODS

In six dogs, superselective embolization was performed with NBCA in five isolated branches of the SMA at the vasa recta level. All dogs were sacrificed 24 hours after embolization. According to the extent of the NBCA mixtures on radiographs of the specimen, embolized segments were divided into group A (embolization of three or fewer vasa recta) or group B (embolization of four or more vasa recta). Histologic evaluation of the mucosal, submucosal, and muscle layers of the embolized segments was performed by a pathologist.

RESULTS

In group A (n=15), histologic findings were normal in seven segments (47%). Mild ischemic changes were noted in the mucosal layer in eight segments, the submucosal layer in four segments, and the muscle layer in one segment. In group B (n=15), ischemic changes were noted in the mucosal layer in all 15 segments, the submucosal layer in 14 segments, and the muscle layer in 10 segments. The difference in ischemic damage between groups A and B was statistically significant.

CONCLUSIONS

Superselective embolization involving three or fewer vasa recta of the SMA was relatively tolerable, and embolization involving four or more vasa recta carried an increased risk of substantial ischemic bowel damage. Further studies are necessary to determine the clinical implications of our findings in human subjects.

Interventional management of lower gastrointestinal bleeding

Lower gastrointestinal bleeding (LGIB) arises from a number of sources and is a significant cause of hospitalization and mortality in elderly patients. Whereas most episodes of acute LGIB resolve spontaneously with conservative management, an important subset of patients requires further diagnostic workup and therapeutic intervention. Endovascular techniques such as microcatheter embolization are now recognized as safe, effective methods for controlling LGIB that is refractory to endoscopic intervention. In addition, multidetector CT has shown the ability to identify areas of active bleeding in a non-invasive fashion, enabling more focused intervention. Given the relative strengths and weaknesses of various diagnostic and treatment modalities, a close working relationship between interventional radiologists, gastroenterologists and diagnostic radiologists is necessary for the optimal management of LGIB patients.

Lower gastrointestinal bleeding: a review

Lower gastrointestinal bleeding (LGIB) continues to be a problem for physicians. Acute LGIB is defined as bleeding that emanates from a source distal to the ligament of Treitz. Although 80% of all LGIB will stop spontaneously, the identification of the bleeding source remains challenging and rebleeding can occur in 25% of cases. Some patients with severe hematochezia require urgent attention to minimize further bleeding and complications. This article reviews the causes, diagnostic methods, and endoscopic treatment of LGIB.

Nonvariceal upper gastrointestinal bleeding

Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding.

Pseudoaneurysm embolization and vasopressin infusion for lower gastrointestinal bleeding due to recurrence of urinary bladder carcinoma

We report a case that was successfully treated for massive lower gastrointestinal (LGI) bleeding due to a recurrent urinary bladder carcinoma. Treatment consisted of combination therapy including embolization of an inferior gluteal artery (IGA) pseudoaneurysm and low-dose arterial vasopressin infusion via a sigmoid artery (SA). A 57-year-old man presented with life-threatening sudden, massive LGI bleeding due to an obturator lymph node (LN) metastasis from a urinary bladder carcinoma. Computed tomography showed that the LN recurrence had invaded all the way to the sigmoid colon, and there was a pseudoaneurysm with extravasation inside the recurrence. An angiogram revealed a left IGA pseudoaneurysm. We therefore excluded the pseudoaneurysm by embolization with microcoils. Following this treatment the bleeding decreased, but intermittent LGI bleeding continued. Endoscopic examination showed the tumor with a huge ulcer inside the colonic lumen, and continuous oozing was confirmed. A second angiogram showed no recurrence of the IGA pseudoaneurysm and no apparent findings of bleeding. Then a 3F microcatheter was placed in the SA selectively using a coaxial catheter system, and vasopressin was infused at a rate 0.05 U/min for 12 h. Bleeding completely ceased 2 days later. There were no signs of ischemic gastrointestinal complications. Massive LGI bleeding has not recurred in 5 months.

[Gastrointestinal bleeding. Diagnostics and therapy by interventional radiology]

Modern imaging modalities such as (multislice) helical CT allow new diagnostic strategies for gastrointestinal hemorrhage. Today, interventional radiology with superselective transcatheter embolization or TIPS procedures allow minimally invasive therapeutic management which can support or replace surgery. This review is a synopsis of the possibilities and relative merits of diagnostic and therapeutic radiological procedures for gastrointestinal bleeding. Which of them to use should be decided collaboratively by gastroenterologist, surgeon, and radiologist depending on local availability, personal experience, and individual patient factors.

Use of a Hydrogel-Coated Self-Expandable Coil to Salvage a Failed Transcatheter Embolization of a Mesenteric Hemorrhage

HydroCoil (MicroVention, Aliso Viejo, CA, USA) is a self-expanding detachable coil developed to improve the endovascular occlusion of intracranial aneurysms. The hydrogel polymer covering the microcoil expands to several times its original diameter to enhance thrombosis of the intended vessel. We made use of this new technology to occlude a mesenteric artery pseudoaneurysm that failed superselective embolization with standard microcoils.