Initial clinical use of a novel mechanical thrombectomy device, XCOILTM, in hemodialysis graft and fistula declot procedures

PURPOSEWe aimed to evaluate the safety and effectiveness of a novel catheter-based mechanical thrombectomy device, XCOILTM, as a first line therapy to restore patency of thrombosed dialysis grafts and fistulae.METHODSIn 2010, 18 consecutive/sequential patients (11 male, 7 female; median age, 52 years; age range, 32–69 years) with occluded arteriovenous grafts (n=15) or fistulae (n=3) were treated with XCOILTM (NexGen Medical Systems Inc.) without adjunctive thrombolytic drugs. XCOILTM was advanced distal to the thrombus within the outflow vein as well as distal to the arterial inflow platelet thrombin plug, using a 4F angiographic catheter. The percentage of thrombus cleared, primary patency, procedure time, and XCOILTM performance were documented.RESULTSThrombosis occurred 1–30 days prior to the procedure. Thrombosed segments of graft/fistula measured 10–50 cm. Pre- and postprocedure angiography demonstrated that in 15 of 18 cases (83%) XCOILTM removed 80%–100% of the venous outflow thrombus. In 11 of 14 cases (79%), the platelet thrombin plug was also removed. Thrombectomy procedure time averaged 8 min, with one to three passes with the XCOILTM required. No evidence of distal embolization or graft/vessel injury was found on angiography following clot removal. In four cases in whom patency was not restored with XCOILTM, subsequent use of other clot removal devices also failed to restore patency. In one case with severe venous stenosis, the device failed to deploy and the thrombus was not captured. No intraprocedural complications related to XCOILTM use occurred.CONCLUSIONXCOILTM is an effective and safe first-line therapy option for the treatment of thrombosed hemodialysis grafts/fistulae. Rapid removal of intact thrombus and platelet thrombin plug can be achieved without adjunctive thrombolytics

Clinical Factors Associated with Dense and Wedge-Shaped Nephrograms Detected 24 h After Chemoembolization

This investigation aimed to evaluate patient characteristics and procedural factors associated with abnormal nephrograms encountered on noncontrast computed axial tomography (CAT) obtained 24-h after transarterial chemoembolization (TACE) for primary and metastatic hepatic malignancies. Sixty hepatic chemoembolization procedures were performed in 29 patients who had a median age of 63 years (range 42–79). The male-to-female ratio was 16:13. Noncontrast CAT scans were obtained approximately 24 h after TACE as part of our institutional protocol and were examined for persistent renal nephrograms. These findings were compared with clinical and procedural parameters to determine whether there was any association with these factors or with the occurrence of acute renal failure (ARF). Abnormally persistent CAT nephrograms were observed 24 h after 28 of 60 (46.7%) TACE procedures, of which 14 (23.3%) were persistent, bilaterally dense, global nephrograms, and 14 (23.3%) were small, wedge-shaped, and focal nephrograms. The change in serum creatinine from baseline to 24 h was significantly greater (p = 0.031) in the global nephrogram group. The presence of cirrhosis, Child-Pugh score, procedure time, baseline renal insufficiency, and lower periprocedural mean arterial blood pressure were also statistically significantly associated with the occurrence of bilateral globally dense nephrograms. The procedure time was statistically significantly associated with the occurrence of wedge-like focally persistent nephrograms. Global, persistently dense nephrograms and wedge-shaped focally persistent nephrograms are not infrequently observed after TACE. Persistent global nephrograms can be an important clinical indicator of ARF. The wedge nephrogram may represent focal renal ischemia

Dual-balloon infusion microcatheter for selective drug-eluting bead transarterial chemoembolization: initial feasibility study

PURPOSE:We aimed to demonstrate feasibility of the use of a dual-balloon infusion microcatheter for segmental/subsegmental drug-eluting bead transarterial chemoembolization (DEB-TACE).METHODS:Over a 16-month period, 15 segmental and 21 subsegmental DEB-TACE procedures were attempted using a dual-balloon anti-reflux microcatheter (IsoFlow™ microcatheter, Vascular Designs Inc.) in 21 patients (15 males; median age, 61 years; range, 49–82 years) with hepatocellular carcinoma (Barcelona clinic liver cancer stage A [n=4]; B [n=12]; C [n=5]) with one to three tumors, median size of 3.4 cm (1.2–9 cm). Follow-up enhanced computed tomography or magnetic resonance imaging was obtained at one month then subsequently every three months for one year. Technical success was evaluated. Modified RECIST criteria was used for target tumor response assessment. Safety was evaluated by assessing for arterial injury and hepatic injury at the time of the procedure and subsequent evidence of complications and liver toxicity.RESULTS:In 26 of the procedures, the segmental/subsegmental arteries were thought not to be easily selected with standard microcatheters due to the arterial branches being severely tortuous/angulated or atretic from prior TACE or anti-angiogenic therapy or could not be catheterized. Radiologic response assessment of treated tumors demonstrated 32% complete response, 19% partial response, 34% stable disease, and 15% progressive disease. No complications occurred. The median time to progression for the targeted tumors was 7 months (range, 3–12 months).CONCLUSION:DEB-TACE, using this dual-balloon anti-reflux infusion microcatheter is feasible and safe

Treatment Planning and Volumetric Response Assessment for Yttrium-90 Radioembolization: Semiautomated Determination of Liver Volume and Volume of Tumor Necrosis in Patients with Hepatic Malignancy

PurposeThe primary purpose of this study was to demonstrate intraobserver/interobserver reproducibility for novel semiautomated measurements of hepatic volume used for Yttrium-90 dose calculations as well as whole-liver and necrotic-liver (hypodense/nonenhancing) tumor volume after radioembolization. The secondary aim was to provide initial comparisons of tumor volumetric measurements with linear measurements, as defined by Response Evaluation Criteria in Solid Tumors criteria, and survival outcomes.MethodsBetween 2006 and 2009, 23 consecutive radioembolization procedures were performed for 14 cases of hepatocellular carcinoma and 9 cases of hepatic metastases. Baseline and follow-up computed tomography obtained 1 month after treatment were retrospectively analyzed. Three observers measured liver, whole-tumor, and tumor-necrosis volumes twice using semiautomated software.ResultsGood intraobserver/interobserver reproducibility was demonstrated (intraclass correlation [ICC] > 0.9) for tumor and liver volumes. Semiautomated measurements of liver volumes were statistically similar to those obtained with manual tracing (ICC = 0.868), but they required significantly less time to perform (p < 0.0001, ICC = 0.088). There was a positive association between change in linear tumor measurements and whole-tumor volume (p < 0.0001). However, linear measurements did not correlate with volume of necrosis (p > 0.05). Dose, change in tumor diameters, tumor volume, and necrotic volume did not correlate with survival (p > 0.05 in all instances). However, Kaplan-Meier curves suggest that a >10% increase in necrotic volume correlated with survival (p = 0.0472).ConclusionSemiautomated volumetric analysis of liver, whole-tumor, and tumor-necrosis volume can be performed with good intraobserver/interobserver reproducibility. In this small retrospective study, measurements of tumor necrosis were suggested to correlate with survival

Initial clinical use of a novel mechanical thrombectomy device, XCOILTM, in hemodialysis graft and fistula declot procedures

PURPOSE: We aimed to evaluate the safety and effectiveness of a novel catheter-based mechanical thrombectomy device, XCOIL™, as a first line therapy to restore patency of thrombosed dialysis grafts and fistulae. METHODS: In 2010, 18 consecutive/sequential patients (11 male, 7 female; median age, 52 years; age range, 32–69 years) with occluded arteriovenous grafts (n=15) or fistulae (n=3) were treated with XCOIL™ (NexGen Medical Systems Inc.) without adjunctive thrombolytic drugs. XCOIL™ was advanced distal to the thrombus within the outflow vein as well as distal to the arterial inflow platelet thrombin plug, using a 4F angiographic catheter. The percentage of thrombus cleared, primary patency, procedure time, and XCOIL™ performance were documented. RESULTS: Thrombosis occurred 1–30 days prior to the procedure. Thrombosed segments of graft/fistula measured 10–50 cm. Pre- and postprocedure angiography demonstrated that in 15 of 18 cases (83%) XCOIL™ removed 80%–100% of the venous outflow thrombus. In 11 of 14 cases (79%), the platelet thrombin plug was also removed. Thrombectomy procedure time averaged 8 min, with one to three passes with the XCOIL™ required. No evidence of distal embolization or graft/vessel injury was found on angiography following clot removal. In four cases in whom patency was not restored with XCOIL™, subsequent use of other clot removal devices also failed to restore patency. In one case with severe venous stenosis, the device failed to deploy and the thrombus was not captured. No intraprocedural complications related to XCOIL™ use occurred. CONCLUSION: XCOIL™ is an effective and safe first-line therapy option for the treatment of thrombosed hemodialysis grafts/fistulae. Rapid removal of intact thrombus and platelet thrombin plug can be achieved without adjunctive thrombolytics