Scott O. Trerotola

Reporting Standards for Percutaneous Interventions in Dialysis Access

THE traditional treatment for failing arteriovenous dialysis access has been thrombectomy and/or surgical revision as needed (1–3). Over the past 2 decades, percutaneous methods for thrombus dissolution and/or correction of anatomic abnormalities have become accepted alternate treatment modalities (4). The results of thrombolysis (5–9), angioplasty (10–14), directional atherectomy (15,16), and endoluminal stent deployment (17–22) have been reported widely; nevertheless, comparison and interpretation of results are difficult because of differing methods of patient selection, treatment, and follow-up. For example, some thrombolysis series report success as establishment of flow immediately after the procedure (5), whereas others require at least three dialysis sessions after treatment for success (8). In addition, different reporting methods (life-table mean patency, life-table 50% patency, arithmetic mean patency, etc) applied to the exact same database can result in dramatically different conclusions; Hodges et al (23) showed that autogenous fistulas could be interpreted to have patencies equal to those of polytetrafluoroethylene (PTFE) grafts, shorter than PTFE grafts, or twice as long as PTFE grafts, depending on the method of data analysis. Suggested standards for reporting the results of arterial revascularization have been published previously by the Journal of Vascular Surgery (24,25) and the Journal of Vascular and Interventional Radiology (26,27). Reporting standards for acute and chronic thromboembolic venous disease have also been suggested (28). These reporting standards are obviously an imperfect fit for dialysis access interventions. To our knowledge, there has been no publication suggesting uniform reporting standards for dialysis access revascularization despite calls for their establishment (23,29). The purpose of this document is to recommend standards to be used for study design and reporting of percutaneous interventions for permanent hemodialysis access. The Table summarizes these standards in an abbreviated format.

Quality Improvement Guidelines for Percutaneous Management of the Thrombosed or Dysfunctional Dialysis Access

John E. Aruny, MD, Curtis A. Lewis, MD, John F. Cardella, MD, Patricia E. Cole, PhD, MD, Andrew Davis, MD, Alain T. Drooz, MD, Clement J. Grassi, MD, Richard J. Gray, MD, James W. Husted, MD, Michael Todd Jones, MD, Timothy C. McCowan, MD, Steven G. Meranze, MD, A. Van Moore, MD, Calvin D. Neithamer, MD, Steven B. Oglevie, MD, Reed A. Omary, MD, Nilesh H. Patel, MD, Kenneth S. Rholl, MD, Anne C. Roberts, MD, David Sacks, MD, Orestes Sanchez, MD, Mark I. Silverstein, MD, Harjit Singh, MD, Timothy L. Swan, MD, Richard B. Towbin, MD, Scott O. Trerotola, MD, Curtis W. Bakal, MD, MPH, for the Society of Interventional Radiology Standards of Practice Committee

The Adrenal Vein Sampling International Study (AVIS) for Identifying the Major Subtypes of Primary Aldosteronism

CONTEXT In patients who seek surgical cure of primary aldosteronism (PA), The Endocrine Society Guidelines recommend the use of adrenal vein sampling (AVS), which is invasive, technically challenging, difficult to interpret, and commonly held to be risky. OBJECTIVE The aim of this study was to determine the complication rate of AVS and the ways in which it is performed and interpreted at major referral centers. DESIGN AND SETTINGS The Adrenal Vein Sampling International Study is an observational, retrospective, multicenter study conducted at major referral centers for endocrine hypertension worldwide. PARTICIPANTS Eligible centers were identified from those that had published on PA and/or AVS in the last decade. MAIN OUTCOME MEASURE The protocols, interpretation, and costs of AVS were measured, as well as the rate of adrenal vein rupture and the rate of use of AVS. RESULTS Twenty of 24 eligible centers from Asia, Australia, North America, and Europe participated and provided information on 2604 AVS studies over a 6-yr period. The percentage of PA patients systematically submitted to AVS was 77% (median; 19-100%, range). Thirteen of the 20 centers used sequential catheterization, and seven used bilaterally simultaneous catheterization; cosyntropin stimulation was used in 11 centers. The overall rate of adrenal vein rupture was 0.61%. It correlated directly with the number of AVS performed at a particular center (P = 0.002) and inversely with the number of AVS performed by each radiologist (P = 0.007). CONCLUSIONS Despite carrying a minimal risk of adrenal vein rupture and at variance with the guidelines, AVS is not used systematically at major referral centers worldwide. These findings represent an argument for defining guidelines for this clinically important but technically demanding procedure.

Nonoperative thoracic duct embolization for traumatic thoracic duct leak: Experience in 109 patients

OBJECTIVE To demonstrate the efficacy of a minimally invasive, nonoperative, catheter-based approach to the treatment of traumatic chyle leak. METHODS A retrospective review of 109 patients was conducted to assess the efficacy of thoracic duct embolization or interruption for the treatment of high-output chyle leak caused by injury to the thoracic duct. RESULTS A total of 106 patients presented with chylothorax, 1 patient presented with chylopericardium, and 2 patients presented with cervical lymphocele. Twenty patients (18%) had previous failed thoracic duct ligation. In 108 of 109 patients, a lymphangiogram was successful. Catheterization of the thoracic duct was achieved in 73 patients (67%). In 71 of these 73 patients, embolization of the thoracic duct was performed. Endovascular coils or liquid embolic agent was used to occlude the thoracic duct. In 18 of 33 cases of unsuccessful catheterization, thoracic duct needle interruption was attempted below the diaphragm. Resolution of the chyle leak was observed in 64 of 71 patients (90%) post-embolization. Needle interruption of the thoracic duct was successful in 13 of 18 patients (72%). In 17 of the 20 patients who had previous attempts at thoracic duct ligation, embolization or interruption was attempted and successful in 15 (88%). The overall success rate for the entire series was 71% (77/109). There were 3 (3%) minor complications. CONCLUSION Catheter embolization or needle interruption of the thoracic duct is safe, feasible, and successful in eliminating a high-output chyle leak in the majority (71%) of patients. This minimally invasive, although technically challenging, procedure should be the initial approach for the treatment of a traumatic chylothorax.

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.

PAVM Embolization: An Update

OBJECTIVE Pulmonary arteriovenous malformations (PAVMs) are most often associated with hereditary hemorrhagic telangiectasia. Untreated, they represent a serious threat due to paradoxical embolization that may manifest as stroke or brain abscess. PAVM treatment is challenging even in the most experienced hands. CONCLUSION Fortunately, new tools and techniques are emerging that may improve the outcomes associated with embolization and reduce some of the risks associated with treating these high-flow lesions. New trends in overall PAVM management are also developing.

Embedded Inferior Vena Cava Filter Removal: Use of Endobronchial Forceps

PURPOSE Removing a retrievable inferior vena cava (IVC) filter can be extremely difficult with the use of standard techniques if the filter is tilted and embedded in the wall of the IVC. The use of rigid endobronchial forceps has been described in case reports to remove embedded IVC filters, and the present report describes the use of this technique to remove a series of tip-embedded IVC filters in two separate institutions. MATERIALS AND METHODS The medical records were reviewed of 21 consecutive patients at two institutions who underwent attempted IVC filter removal with rigid endobronchial forceps over a 34-month period. The mean age of patients was 32.4 years (range, 14.1-54.1 y). The patients had the following filters: Recovery (n = 6), G2 (n = 10), Günther Tulip (n = 4), and OptEase (n = 1). RESULTS Rotational or biplane venography was used to confirm that the filters were tilted and embedded in the wall of the IVC in all 21 patients. Rigid endobronchial forceps were used successfully to remove 20 embedded IVC filters in 21 patients. There was one case of failure to remove an embedded suprarenal G2 filter. There were no major complications. CONCLUSIONS Rigid endobronchial forceps may be used as a reliable option for removal of embedded IVC filters.

Hemobilia after percutaneous transhepatic biliary drainage: treatment with transcatheter embolotherapy.

Thirteen of 333 patients who underwent percutaneous biliary drainage (PBD) developed severe hemobilia. Hepatic arteriography successfully demonstrated the source of hemorrhage in all 13 patients. Lesions included hepatic artery pseudoaneurysm in nine, hepatic artery-bile duct fistulas in four, and a hepatic artery-portal vein fistula in one patient. Hemobilia occurred from 1 day to 1.8 years (mean, 100 days) following catheter placement. Embolization agents used included Hilal embolization microcoils, occluding spring emboli, cyanoacrylate, detachable balloons, and gelatin sponge pledgets. A single agent was used in eight cases (62%), multiple agents were used in four cases (31%), and in one case (7%), spontaneous thrombosis of the pseudoaneurysm occurred during catheter manipulation. In five patients, the source of the hemorrhage could only be demonstrated following removal of the biliary catheter(s) over guide wire(s). Initial embolization was successful in stopping hemobilia in 12 patients. One patient required repeat embolization after 4 months. Postembolization complications included hepatic abscess formation in two patients and a sterile hepatic infarct in one patient. This series indicates that transcatheter embolotherapy is an effective method for the treatment for severe hemobilia.

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.

Percutaneous Transhepatic Venous Access for Hemodialysis

Percutaneous transhepatic venous access is an option for hemodialysis patients who have exhausted more traditional sites of venous access. Thirty-six transhepatic dialysis catheters were placed in 12 patients. The mean time of the catheters in situ was 24.3 days. Twenty-one catheters were replaced or removed because of catheter thrombosis, yielding a catheter thrombosis rate of 2.40 per 100 catheter-days. The line sepsis rate was 0.22 per 100 catheter-days. Poor patency rates were seen because of a high rate of late thrombosis. Transhepatic dialysis catheters should only be used as a last resort unless limitations of catheter thrombosis can be overcome.