Safety and Risk of Superselective Transcatheter Arterial Embolization for Acute Lower Gastrointestinal Hemorrhage with N-Butyl Cyanoacrylate: Angiographic and Colonoscopic Evaluation.

PURPOSE: To retrospectively evaluate the safety and risk of transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) for urgent acute arterial bleeding control in the lower gastrointestinal tract by angiography and colonoscopy. MATERIALS AND METHODS: NBCA TAE was performed in 16 patients (mean age, 63.7 y) with lower gastrointestinal bleeding (diverticular hemorrhage, tumor bleeding, and intestinal tuberculosis). Angiographic evaluation was performed by counting the vasa recta filled with casts of NBCA and ethiodized oil (Lipiodol) after TAE. Patients were classified as follows: group Ia, with a single vas rectum with embolization of 1 branch (n = 6); group Ib, with a single vas rectum with embolization of ≥ 2 branches (n = 8); group II, with embolization of multiple vasa recta (n = 2). All patients underwent colonoscopy within 1 month, and ischemic complications (ulcer, scar, mucosal swelling, fibrinopurulent debris, and necrosis) were evaluated. RESULTS: The procedure was successful in all patients. No ischemic change was observed in any patients in group Ia and in two patients in group Ib. Ischemic changes were observed in six group Ib patients and both group II patients. Group Ib patients experienced ischemic complications that improved without treatment. One patient in group II underwent resection for intestinal perforation after embolization of three vasa recta. One patient in group II with sigmoid stricture with embolization of six vasa recta required prolonged hospitalization. CONCLUSIONS: NBCA embolization of ≥ 3 vasa recta can induce ischemic bowel damage requiring treatment. NBCA TAE of one vas rectum with ≥ 2 branches could also induce ischemic complications. However, these were silent and self-limited.

Transcatheter arterial embolization of acute arterial bleeding in the upper and lower gastrointestinal tract with N-butyl-2-cyanoacrylate.

PURPOSE: To assess the clinical utility and safety of transcatheter arterial embolization with N-butyl-2-cyanoacrylate (NBCA) for urgent control of acute arterial bleeding in the upper and lower gastrointestinal tract. MATERIALS AND METHODS: Therapeutic NBCA embolization was performed in 37 patients (39 cases; mean age, 67.8 years) with acute upper (n = 16) or lower (n = 23) gastrointestinal tract bleeding after endoscopic management had failed. Transcatheter arterial embolization was performed using 1:1 to 1:5 mixtures of NBCA and iodized oil. The most common etiologies of bleeding were colonic diverticulosis (n = 13), malignancy (n = 11), and benign ulcer (n = 7). Coagulopathy was present in 11 patients, and 23 patients were hemodynamically unstable before NBCA embolization. Histologic examination for bowel ischemia was also performed in five patients who underwent excision of the lesion after NBCA embolization. RESULTS: The technical success rate was 100%. Recurrent bleeding occurred in two patients. Complete hemostasis was achieved in all 11 patients with coagulopathy. Ulcers induced by transcatheter arterial embolization were noted in 6 of 20 patients who underwent endoscopic examination; the ulcers were successfully treated with conservative measures. Histologic examination revealed that despite inflammatory reactions in and around the vessels, no intestinal necrosis secondary to NBCA embolization was found. Hepatic abscess occurred in two cases, and ischemia of the lower limb occurred in one case; these complications were managed by percutaneous drainage and bypass surgery. CONCLUSIONS: Transcatheter arterial embolization with NBCA is a good treatment option with a high rate of complete hemostasis and a low recurrent bleeding rate, even in patients with coagulopathy.

Development of a re-positionable aortic stent-valve: a preliminary study in swine.

BACKGROUND: Placement of aortic stent-valves in the proper position is difficult due to the high velocity and oscillation of blood flow and anatomical characteristics. To address this problem, a re-positionable stent-valve was designed and examined in a preliminary animal experiment. METHODS: Protocols for this animal study were approved by the institutional Animal Care and Use Committee. An umbrella-shaped polyurethane valve was attached at the tip of newly devised re-positionable metallic stent. The prosthesis (re-positionable stent-valve) was implanted in 5 female pigs via the right carotid artery using a 10-F introducer (Group A). As a control, the stent-without-valve was implanted in 4 female pigs (Group B). Efficacy of the valve was assessed by aortography and aortic pressure measurement. Animals were sacrificed 1 hour after stent-valve implantation for macroscopic examination. RESULTS: The stent-valve was successfully implanted in all pigs. In Group A, aortography showed good function of the polyurethane valve. No significant change in diastolic pressure was noted during valve testing. In Group B, aortography and aortic pressure measurement showed massive aortic regurgitation following dysfunction of the native aortic leaflets. Post-mortem examination showed small amounts of thrombus inside the polyurethane umbrella in Group A. CONCLUSION: Placement of the re-positionable stent-valve seems feasible and effective. However, the problem of thrombus formation inside the umbrella valve should be solved in future studies.

Suitable blending method of lipiodol-cisplatin in transcatheter arterial embolization for hepatocellular carcinoma: evaluation of sustained release and accumulation nature.

BACKGROUND/AIMS: Recently, fine powder cisplatin (IA-call; Nipponkayaku, Japan) was released, but there is no detailed study on an appropriate blending method of lipiodol-cisplatin for transcatheter arterial chemoembolization. We evaluated the sustained release and accumulation nature of lipiodol-cisplatin for hepatocellular carcinoma. METHODOLOGY: We prepared three types of mixture: a suspension of lipiodol and cisplatin powder, an emulsion of cisplatin powder dissolved with contrast medium and lipiodol, and a suspension-emulsion that was a suspension of lipiodol and cisplatin powder emulsified with contrast medium. In a basic study, a cisplatin release test was performed. In a clinical evaluation, transcatheter arterial chemoembolization with 3 lipiodol-cisplatin mixtures that had sustained release was performed in 60 consecutive patients with hepatocellular carcinoma as a randomized controlled trial. The density ratio of the tumor and treated liver tissue was measured as the accumulation nature. RESULTS: The suspension-emulsion and emulsion with a 7:3 mixture of lipiodol and contrast medium, and the suspension had better sustained release. The accumulation nature of the suspension-emulsion and emulsion were higher than the suspension. CONCLUSIONS: The pattern efficiently accumulated on hepatocellular carcinoma was the suspension-emulsion and emulsion. We suggest that a suspension-emulsion may be created more easily and is more suitable for clinical use.

Phase II study on hepatic arterial infusion chemotherapy using percutaneous catheter placement techniques for liver metastases from colorectal cancer (JFMC28 study).

AIM: This prospective multicenter study aimed to evaluate the efficacy and adverse events of hepatic arterial infusion chemotherapy (HAIC) using percutaneous catheter placement techniques for liver metastases from colorectal cancer (CRC). METHODS: We administered 5-fluorouracil at 1000 mg/m2 over 5 h via hepatic arterial infusion on a weekly schedule. The primary endpoint was the overall response rate (RR). The secondary endpoints were the overall survival (OS), progression-free survival (PFS) and toxicities. RESULTS: Between February 2000 and March 2002, seventy-seven eligible patients were enrolled in this study. After a median of 26 treatment cycles, 4 patients achieved a complete response, 29 achieved a partial response, 28 had stable disease, 15 had progressive disease and the status of one patient was unknown. The overall RR was 42.9% and the disease control rate (DCR) was 79.2%. The median PFS and OS times were 203 and 560 days, respectively. The most common grade 3 or 4 hematological and non-hematological toxicities were total bilirubin level elevation (10.4%) and gamma-glutamyl transferase level elevation (10.4%). With regard to the relationship between the background factors and treatment outcomes, the DCR, RR, PFS and OS were different between patients with and without extrahepatic lesions (DCR: 86.5% vs 64%, RR: 46.2% vs 36.0%, PFS: 233 days vs 99 days, OS: 587 days vs 558 days). CONCLUSION: The primary endpoint of this study was not met. HAIC using percutaneous catheter placement techniques did not improve the RR for liver metastasis from CRC.

Balloon-assisted coil embolization of the celiac trunk before endovascular aortic repair of thoracoabdominal aortic aneurysm.

PURPOSE: Celiac trunk coil embolization before thoracic endovascular aneurysm repair (TEVAR) of a thoracoabdominal aortic aneurysm involving the celiac trunk can prevent type II endoleaks. One disadvantage of conventional coil embolization is the risk of coil displacement. We performed coil embolization under balloon occlusion of the celiac trunk to address this issue. MATERIALS AND METHODS: Between December 2008 and January 2011, 5 patients (3 men and 2 women, mean age 76 years) were included in this study. For all patients, after confirming the collateral blood flow from the superior mesenteric artery via the pancreaticoduodenal arcades by using the balloon occlusion test, celiac trunk coil embolization proceeded under balloon occlusion of the proximal part of the celiac trunk. RESULTS: Balloon-assisted coil embolization of the celiac trunk was completed for all patients without any complications. All coils were deployed as planned in the short segment of the celiac trunk without displacement. Coil migration, ischemic complications, and endoleaks via the celiac trunk did not arise in any of the patients over a follow-up period of 77-637 (mean 258) days. CONCLUSIONS: Balloon-assisted coil embolization of the celiac trunk before TEVAR could be a feasible treatment option for suitable patients.

Influence of ethanol-induced pulmonary embolism on hemodynamics in pigs.

AIMS AND OBJECTIVES: Ethanol is widely used for the embolization treatment of vascular malformations, but it can also cause serious complications such us pulmonary hypertension, cardiopulmonary collapse and death. The complications are considered secondary to pulmonary vasospasm and ethanol-induced sludge embolism, etc., We studied the hemodynamic effects of intravenous absolute ethanol injection and ethanol sludge injection in pigs. MATERIALS AND METHODS: A total of 5 pigs underwent intravenous injection of ex vivo generated ethanol-induced sludge in which residual ethanol was removed (Group S) and 4 pigs underwent intravenous injection of absolute ethanol (Group E). Hemodynamic parameters related to the pulmonary and systemic circulation were compared between the groups. RESULTS: Transient pulmonary hypertension was observed in both groups and the hemodynamic changes were similar in both groups. CONCLUSIONS: Sludge can induce transient pulmonary hypertension or cardiopulmonary collapse, without ethanol and may be the mechanism by which ethanol induces its adverse hemodynamic effects.

Development of a new hanging-type esophageal stent for preventing migration: a preliminary study in an animal model of esophagotracheal fistula.

PURPOSE: Covered, self-expandable metallic stents (SEMS) have been enthusiastically adopted for the treatment of esophagotracheal fistula, but problems with stent migration have yet to be resolved. To overcome this problem, we have developed a new hanging-type esophageal stent designed to prevent migration, and we conducted an animal study to assess the efficacy of our method. METHODS: A total of six female pigs were used in this study. The main characteristic of our stent was the presence of a string tied to the proximal edge of the stent for fixation under the skin of the neck. The first experiment was performed to confirm technical feasibility in three pigs with esophagotracheal fistula. The second experiment was performed to evaluate stent migration and esophagotracheal fistula in three pigs. RESULTS: Creation of the esophagotracheal fistula and stent placement were technically successful in all pigs. In the first experiment, esophagotracheal fistula was sealed by stent placement. In the second experiment, no stent migration was seen 11 or 12 days after stent placement. Gross findings showed no fistulas on the esophageal or tracheal wall. CONCLUSIONS: Our new hanging-type esophageal stent seems to offer a feasible method for preventing stent migration.