Jeffrey I. Mondschein

Experience with the recovery filter as a retrievable inferior vena cava filter.

PURPOSE This study evaluates clinical experience with the Recovery filter as a retrievable inferior vena cava (IVC) filter. MATERIALS AND METHODS One hundred seven Recovery filters were placed in 106 patients with an initial clinical indication for temporary caval filtration. Patients were followed up to assess filter efficacy, complications, eventual need for filter removal, time to retrieval, and ability to remove the filter. RESULTS The patient cohort consisted of 62 men and 44 women with a mean age of 48 years (range, 18-90 y). Mean implantation time was 165 days. Indications for filter placement in patients with deep vein thrombosis (DVT) and/or pulmonary embolism (PE) included contraindication to anticoagulation (n = 33), complications of anticoagulation (n = 8), poor cardiopulmonary reserve (n = 6), large clot burden (n = 3), and PE while receiving anticoagulation (n = 1). Indications for filter placement in patients without proven PE or DVT included immobility after trauma (n = 35); recent intracranial hemorrhage, neurosurgery, or brain tumor (n = 18); and other surgical or invasive procedure (n = 3). Three patients (2.8%) had symptomatic PE after placement of the Recovery filter. No caval thromboses were detected. No symptomatic filter migrations occurred. Recovery filter removal was attempted in 15 of 106 patients (14%) at a mean of 150 days after placement. The Recovery filter was successfully retrieved in 14 of 15 patients (93%); one removal was unsuccessful at 210 days after placement. Ninety-two filters (87%) currently remain in place. CONCLUSIONS Although all the filters were placed with the intention of being removed, a large percentage of filters were not retrieved. The Recovery filter was safe and effective in preventing PE when used as a retrievable IVC filter.

Chemoembolization of colorectal liver metastases with cisplatin, doxorubicin, mitomycin C, ethiodol, and polyvinyl alcohol

Unresectable colorectal liver metastases have a 1‐ and 2‐year survival of 55% and 33% with current systemic therapies. The authors evaluated response and survival after transarterial chemoembolization.

Relationship between Chest Port Catheter Tip Position and Port Malfunction after Interventional Radiologic Placement

PURPOSE The relationship between catheter tip position of implanted subcutaneous chest ports and subsequent port malfunction was investigated. Tip movement from initial supine position to subsequent erect position was also evaluated. MATERIALS AND METHODS Patients who underwent imaging-guided internal jugular chest port placement between July 2001 and May 2003 were identified with use of a quality-assurance database. Sixty-two patients were included in the study (22 men and 40 women), with a mean age of 58 years (range, 27-81 years). Catheter tip location on the intraprocedural chest radiograph was determined with use of two methods. First, the distance from the right tracheobronchial angle (TBA) was recorded (TBA distance). Second, tip location was classified into six anatomic regions: 1, internal jugular veins; 2, brachiocephalic veins; 3, superior vena cava (SVC; n = 11); 4, SVC/right atrial junction (n = 22); 5, upper half of right atrium (n = 25); and 6, lower half of right atrium (n = 4). For the duration of follow-up, catheter tip location was documented, as were all episodes of catheter malfunction. RESULTS Patients with catheter tips initially placed in position 3 had a higher risk of port malfunction (four of 11; 36%) than patients with catheter tips located in position 5 (two of 25; 8%). This difference narrowly fell short of statistical significance (P =.057). When comparing intraprocedural chest radiographs to the first erect chest radiographs, significant upward tip movement was noted. The tips migrated cephalad an average of 20 mm (P =.003) and 1.0 position units (P =.001). DISCUSSION Catheter tips placed in the SVC tended to have a greater risk of port malfunction compared with those positioned in the right atrium. Chest ports migrated cephalad between the supine and erect positions.

Single-center Experience with the Arrow-Trerotola Percutaneous Thrombectomy Device in the Management of Thrombosed Native Dialysis Fistulas

PURPOSE The present study sought to evaluate the performance of the Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) in the treatment of native fistula thrombosis in a U. S. hemodialysis population. Specifically, the technical success, clinical success, complication rate and type, primary and secondary patency rates, effect of adjunctive thrombolytic therapy, and any variables that affected outcomes of procedures in which this device was used were analyzed. MATERIALS AND METHODS Forty-two patients with 44 thrombosed native fistulas (17 radiocephalic, 10 brachiocephalic, 10 transposed or superficialized, five graft/fistula hybrids, and two leg fistulas) were treated with 62 mechanical thrombolysis procedures with use of the PTD. All patients had large clot burden. The device type was recorded in 43 procedures: standard (n = 21), over-the-wire (OTW; n = 19), or both (n = 3). No device was used in two cases because of inability to cross the anastomosis. Adjunctive therapies (n = 18) included the use of tissue plasminogen activator (tPA; n = 16) and deployment of the AngioJet device with (n = 1) or without tPA (n = 1). Stents were inserted in four procedures. Outcome variables included technical and clinical success, complications, and primary and secondary patency. Cox proportional-hazards regression and Kaplan-Meier analyses were performed. RESULTS The technical success rate was 87% (54 of 62) and the clinical success rate was 79% (49 of 62). Percutaneous transluminal angioplasty was performed in all but two procedures. Complications occurred in 13% of procedures (n = 8); three resulted in technical failure. The primary patency rates were 38% at 6 months and 18% at 12 months; secondary patency rates were 74% and 69%, respectively. Outcomes were not affected by adjunctive techniques, fistula type, age of fistula, device type (ie, OTW vs standard), or patient sex. Secondary patency was superior when no residual clot or stenosis was present (P = .003). CONCLUSIONS The PTD is effective for percutaneous treatment of thrombosed hemodialysis fistulas, with good short- and long-term outcomes in a U.S. population. Within the limitations of a retrospective study with a small sample size, use of an adjunctive thrombolytic agent did not appear to improve results compared with the use of the device alone.

Removal of retrievable inferior vena cava filters with computed tomography findings indicating tenting or penetration of the inferior vena cava wall.

PURPOSE To examine the feasibility and safety of removing retrievable inferior vena cava (IVC) filters with struts external to the IVC wall on computed tomography (CT) imaging. MATERIALS AND METHODS This retrospective study included 64 IVC filter retrievals from 62 patients over a 5-year period. CT images obtained before retrieval were used to describe the various imaging characteristics of filter interactions with the IVC wall. Patient medical records were reviewed for filter type, results of filter removal with standard or nonstandard techniques, and complications. RESULTS Filter struts outside the IVC wall were a common finding on CT with 55 (85.9%) filters showing some degree of perforation. Of 64 filters, 57 (89.1%) were removed successfully; 7 (10.9%) filters could not be removed because of incorporation of filter struts or tip into the IVC wall. Before retrieval, filter fracture was detected in eight (12.5%) cases, and IVC stenosis was present in three (4.7%) cases. No major complications occurred during any retrieval. Two (3.1%) cases were complicated by postprocedure abdominal pain. Both cases clinically resolved, and no abnormalities were detected on postprocedure CT. CONCLUSIONS The appearance of filter struts tenting or penetrating the IVC wall is a common finding on CT performed before filter retrieval. IVC filters with these findings can be removed safely and should not be a contraindication for IVC filter retrieval.

Triple-lumen peripherally inserted central catheter in patients in the critical care unit: prospective evaluation.

PURPOSE To prospectively evaluate outcomes associated with use of a triple-lumen (TL) peripherally inserted central catheter (PICC) in the intensive care unit (ICU) setting. MATERIALS AND METHODS Patients were prospectively enrolled in this HIPAA-compliant, institutional review board-approved study. Informed consent was obtained. All patients were in one hospitals ICUs and needed intermediate-term central venous access requiring three lumina. A 6-F tapered TL PICC was placed by a bedside nursing-based team with backup from the Interventional Radiology department. Placement complications, as well as long-term complications, were recorded. At catheter removal, ultrasonography (US) of the veins containing the TL PICC was performed to detect occult venous thrombosis. Regardless of indication for removal, catheters were sent for culture to detect colonization. RESULTS The study was stopped prematurely after 50 of a planned 167 patients were enrolled when a scheduled interim analysis detected a venous thrombosis rate that was considered unacceptably high by the study oversight committee (thrombosis was symptomatic in 20% of patients [10 of 50]). Venous thrombosis (symptomatic or asymptomatic) was detected in 26 of 45 patients (58%; 95% confidence interval [CI]: 43%, 72%) examined with US. Documented catheter-related bloodstream infection did not occur (0%; 95% CI: 0%, 7%); colonization was detected in three of 29 catheter tips sent for culture (10%; 95% CI: 2%, 27%). Catheter malfunction and dislodgment occurred in one patient each. CONCLUSION The TL PICC design used in this study resulted in unacceptably high venous thrombosis rates. Even when used in a high-risk setting for infection (ie, the ICU), rates of clinically evident infection and colonization were absent and low, respectively.

Physical Examination versus Normalized Pressure Ratio for Predicting Outcomes of Hemodialysis Access Interventions

PURPOSE The ratio of intragraft venous limb pressure (VLP) to systemic pressure (S) has been proposed to help determine the endpoint of hemodialysis access interventions. It was hypothesized that physical examination of the access could be used in the same way and these techniques were compared as predictors of outcome. PATIENTS AND METHODS With use of a quality-assurance database, records from 117 hemodialysis access interventions were retrospectively reviewed. Only interventions in grafts were included. The database included physical examination (to establish thrill, thrill with slight pulsatility [TSP], pulse with slight thrill [PST], and pulse) at three locations along the graft (proximal, midportion, and distal), normalized pressure ratio calculated with S from a blood pressure cuff (S(cuff)) and S within the graft with outflow occluded (S(direct)), graft configuration and location, indication, operator, and time to next intervention (outcome of primary patency). Only procedures with complete follow-up data were included in the analysis (n = 97; declotting, n = 51; prophylactic percutaneous transluminal angioplasty [PTA], n = 46). Statistical analysis was performed with use of Cox proportional-hazards regression. RESULTS Graft configuration, location, side, VLP, S(direct), and S(cuff) did not affect outcomes. An operator effect was noted for two physicians and was adjusted for in all analyses. Pressure ratios were weak predictors of outcome (VLP/S(direct), P =.07; VLP/S(cuff), P =.08) and suggested that patency increased with increasing pressure ratio, contrary to earlier studies. Procedure type predicted outcome (declotting, median patency of 50 days; PTA, median patency of 105 days; P =.01). Thrill at distal physical examination was predictive of outcome (P =.04) and even more so when thrill and TSP combined were compared with PST and pulse combined (P =.03). Similar but less-pronounced effects were seen at midportion and proximal physical examinations. CONCLUSIONS The presence of a thrill or slightly pulsatile thrill at the distal (venous) end of a dialysis graft is the best predictor of outcome after percutaneous intervention. Based on the present study, the authors believe that physical examination of dialysis access should supplant pressure measurements as an endpoint of intervention and should serve as an essential component of quality assurance of access interventions.

Radiofrequency Ablation of Small Renal Cell Carcinomas Using Multitined Expandable Electrodes: Preliminary Experience

PURPOSE Radiofrequency ablation is a minimally invasive, nephron-sparing option for renal cell carcinoma (RCC) in poor surgical candidates. We report our contemporary experience with RCC radiofrequency ablation using multitined expandable electrodes along with an aggressive treatment strategy to displace adjacent viscera away from probe tines. Involution of the treatment zone was assessed over time. MATERIALS AND METHODS Over a 36-month period, a quality-assurance database identified 22 patients with 26 sporadic RCC who underwent 43 ablations during 27 radiofrequency ablation sessions. The mean age of the cohort was 71 years (range, 47-89 y). Mean RCC diameter was 2.2 cm (range, 1-4 cm). Twenty-six of radiofrequency ablation sessions were performed using multitined expandable electrodes. All ablations used CT guidance with moderate sedation. Adjunctive techniques used during ablation were recorded, as were instances in which ablation mandated penetration of tines beyond the kidney margin. Post-treatment ablation zones were measured from CT/MR images to evaluate serial involution and treatment response. RESULTS Technical success in targeting and ablation was 100%. Follow-up periods ranged from 1 to 31 months (mean, 11.2). During this period, one patient presented with marginal local recurrence and underwent repeat radiofrequency ablation. Adjunctive techniques in four patients included water injection for displacement of the tail of the pancreas (n = 1) or descending colon (n = 3). Deliberate penetration of tines beyond the margins of the kidney was performed in 41% of cases; no hemorrhage occurred in these cases. No major complications occurred. Minor complications occurred in 17% of patients, including asymptomatic pneumothorax, perirenal hematomas, subcutaneous hematoma, and subcutaneous abscess. After 6 months, mean involution of the ablation zone was 15% from baseline volume per year. CONCLUSION Multitined expandable radiofrequency electrodes produce a high rate of local control for small RCCs with a low complication rate, even when tine penetration of the kidney is required for an adequate tumor treatment margin. Adjacent organs can be protected with adjunctive percutaneous maneuvers.

Effectiveness of an Aggressive Antibiotic Regimen for Chemoembolization in Patients with Previous Biliary Intervention

PURPOSE Liver abscess occurs in most patients with biliary stents or bypass undergoing chemoembolization despite the use of standard prophylactic antibiotics. The present study was conducted to investigate the efficacy of an aggressive prophylactic regimen to prevent abscess in such patients. MATERIALS AND METHODS Between November 2002 and July 2005, 16 chemoembolization procedures were performed in seven patients who had undergone biliary intervention. Prophylaxis was initiated with levofloxacin 500 mg daily and metronidazole 500 mg twice daily 2 days before chemoembolization and continued for 2 weeks after discharge. A bowel preparation regimen was given with neomycin 1 g plus erythromycin base 1 g orally at 1 p.m., 2 p.m., and 11 p. m. the day before chemoembolization. With the Fisher exact test, the incidence of infectious complications was compared with previously reported data for patients with and without earlier biliary intervention who had received standard prophylaxis. RESULTS Liver abscess occurred in two of seven patients after two of 16 procedures. Previously reported incidences were six of seven patients (P=.103) and six of 14 procedures (P=.101) among patients with previous biliary intervention receiving standard prophylaxis and one of 150 patients (P=.005) and one of 383 procedures (P=.004) among patients with no previous biliary intervention. CONCLUSIONS There was a trend toward a lower rate of abscess formation among patients at high risk who received more aggressive antibiotic prophylaxis, but the difference did not reach statistical significance. The rate of infection remained significantly higher than among patients without previous biliary intervention.

Impact on renal function of percutaneous thermal ablation of renal masses in patients with preexisting chronic kidney disease.

PURPOSE To examine the effect of percutaneous thermal ablation of renal masses on renal function among patients with baseline chronic kidney disease (CKD). MATERIALS AND METHODS Patients with baseline CKD (initial glomerular filtration rate [GFR] < 60 mL/min/1.73 m(2)) who underwent percutaneous cryoablation or radiofrequency (RF) ablation of renal masses were reviewed. RESULTS A total of 48 patients with a GRF of 60 mL/min/1.73 m(2) or lower were treated with renal cryoablation or RF ablation and had follow-up GFR measurement 1 month afterward. Mean patient age was 73 years (range, 47-89 y). Cryoablation was performed in 22 patients and RF ablation was performed in 26. Mean tumor diameter was 3.4 cm (range, 0.9-10.2 cm). Mean overall GFRs were 39.8 mL/min/1.73 m(2) at baseline and 39.7 mL/min/1.73 m(2) at 1 month after ablation (P = .85). A total of 38 patients had 1-year follow-up GFR measurement (cryoablation, n = 18; RF ablation, n = 20), and their mean GFR was 40.9 mL/min/1.73 m(2) ± 11.4 (SD), compared with a preablation GFR of 41.2 mL/min/1.73 m(2)(P = .79). In the cryoablation group, mean GFRs at 1 month and 1 year were 41.4 mL/min/1.73 m(2) and 44.4 mL/min/1.73 m(2), compared with respective baseline GFRs of 41.1 mL/min/1.73 m(2) and 42.1 mL/min/1.73 m(2) (P = .75 and P = .19, respectively). In the RF ablation group, mean GFRs at 1 month and 1 year were 38.2 mL/min/1.73 m(2) and 37.8 mL/min/1.73 m(2), compared with respective baseline GFRs of 38.7 mL/min/1.73 m(2) and 40.4 mL/min/1.73 m(2) (P = .58 and P = .09, respectively). CONCLUSIONS Independent of ablation modality, percutaneous renal mass ablation does not appear to affect renal function among patients with CKD.