Anthony C. Venbrux

A New Optional Vena Cava Filter: Retrieval at 12 Weeks in an Animal Model

PURPOSE To test the feasibility and safety of percutaneous retrieval of a new inferior vena cava (IVC) filter, the Recovery Filter (RF), acutely and after 12-week implantation in sheep. MATERIALS AND METHODS The RF is a bilevel filter with stabilizing arms and elastic hooks that allow retrieval with a unique retrieval cone after incorporation into the wall of the IVC. Twenty-four filters were placed in the infrarenal IVCs of 18 sheep. In six sheep, two filters were placed and then removed immediately; three sheep were killed acutely and three were killed after a healing period of 3 weeks. In 12 sheep, a single filter was placed and then removed 12 weeks later; six were killed after retrieval and six were killed after an 8-week healing period. RESULTS The mean (+/-SD) transverse vena caval diameter was 15.3 mm +/- 2. All filters were deployed as intended and retrieved without difficulty. At sacrifice, there was no evidence of IVC perforation or retroperitoneal abnormality. The IVCs of the animals in the acute retrieval group showed minimal acute superficial injury that was largely reversed at 3 weeks. At 12 weeks, there was evidence of transmural incorporation of filter elements with narrowing of the IVCs. Solitary fibrotic abnormalities were present in the aorta adjacent to IVC lesions in nine of the 12 animals in the 12-week group. The IVC and aortic abnormalities were largely healed, with reversal of IVC narrowing after 8 weeks. CONCLUSION The recovery filter can be reliably and safely retrieved acutely and 12 weeks after implantation in sheep.

Use of the 8-F Angio-Seal Vascular Closure Device in Large-Caliber Arteriotomies

Purpose To evaluate the feasibility and safety of using the 8-F Angio-Seal vascular closure device (VCD) to seal large-caliber (>8-F) access sites during percutaneous endovascular interventions. Methods A retrospective review was undertaken of 42 consecutive patients (34 men; mean age 67.8 years, range 36–94) undergoing percutaneous peripheral interventions with sheaths ranging from 9-F to 12-F and subsequent closure using 8-F Angio-Seal VCDs. Single-wall puncture (n = 48) of the common femoral artery was guided by ultrasound in 46 cases and palpation in 2. Forty procedures required therapeutic heparinization during the interventional procedure; protamine was administered in only 5. Per protocol, manual pressure was held for 15 minutes. Clinical and/or imaging follow-up was available in all cases within 3 months after the procedure. Results Immediate technical success was achieved in all cases, with hemostasis obtained within 5 minutes (no oozing or hematoma). The overall complication rate was 4.1% (2/48); one hematoma requiring surgical repair occurred 10 hours after VCD deployment. An asymptomatic pseudoaneurysm was discovered on follow-up imaging and was treated with ultrasound-guided thrombin injection with complete resolution. Conclusion The use of the 8-F Angio-Seal VCD to close large-caliber arteriotomies ranging from 9-F to 12-F is feasible and safe, with a low complication rate.

Experimental Evaluation of a New Transcatheter Vascular Embolization Device in the Swine Model

PURPOSE To evaluate a new transcatheter device suitable for arterial embolization in an animal model. MATERIALS AND METHODS A new prototype self-expanding braided embolic device (Embolizor), consisting of nitinol wire strands fixed at either end with platinum-iridium bands and covered with a film of polyethylene, was deployed through 5-F diagnostic catheters into renal artery branches in five swine. Standard stainless-steel spring coils were deployed in other renal branches and served as controls. The animals underwent follow-up selective renal arteriography to determine presence or absence of vessel recanalization or device migration 15-23 days after device deployment. Histopathologic evaluation of target vessels and peripheral renal parenchyma was also performed. RESULTS Ten Embolizors and 10 stainless-steel coils were deployed in arteries ranging in size from 1.8 to 3.0 mm in diameter. The Embolizor was easily and precisely deployed. Angiographic evidence of vascular occlusion in the Embolizor group was noted within 30 seconds in eight device deployments and within 5 minutes in two. No early or delayed device migration was noted on follow-up arteriography. In the control group, seven of 10 previously occluded arteries were recanalized. No recanalization was noted in the Embolizor group. Light microscopy revealed evidence of infarction in all specimens examined. Whereas three specimens in the Embolizor group contained occasional giant cells, there were numerous multinucleated giant cells present within the interstices of all control spring coils. CONCLUSION The Embolizor was easily, precisely, and successfully deployed through standard selective diagnostic angiographic catheters. Short-term follow-up demonstrated no recanalization or migration of the device. The Embolizor was shown on histopathologic analysis to have no significant foreign body reaction.

Retrieval of TRAPEASE and OPTEASE Inferior Vena Cava Filters with Extended Dwell Times.

PURPOSE To demonstrate that OPTEASE and TRAPEASE filters can be removed after dwell times greater than 60 days. MATERIALS AND METHODS A retrospective review was performed of patients who underwent an attempted removal of a TRAPEASE or OPTEASE filter with a greater than 60-day dwell time between 2009 and 2015 at a single institution. Eleven patients within that time span were identified, and 10 were included in the review. One patient was excluded from the study because the date of filter placement was unknown. RESULTS All filters were successfully retrieved. The average dwell time for removed TRAPEASE filters was 1,273 days (range, 129-3,582 d), with a median of 492 days (n = 5). The average dwell time for OPTEASE filters was 977 days (range, 123-2,584 d), with a median of 661 days (n = 5). The average dwell time of all filters was 1,125 days (range, 123-3,582 d), with a median of 577 days (n = 10). All patients exhibited inferior vena cava (IVC) stenosis after filter retrieval. An IVC pseudoaneurysm was present following retrieval in one case and resolved. In one case, a fractured filter strut was left completely embedded in the caval wall. Two patients reported unilateral leg swelling on clinical follow-up, and the remainder reported no leg swelling or tightness. CONCLUSIONS Initial experience suggests that TRAPEASE and OPTEASE filters can be removed after extended dwell times.

Management of Chronic Pancreatitis with Dilation of Main Pancreatic Duct Strictures Using Percutaneously Inserted Internal/external Drainage Catheters

hemidiaphragm leading to a temporary conduit between the peritoneal and pleural spaces. Hydrothorax (“sweet hydrothorax”) originally described in 1967 (1) as a complication of continuous ambulatory PD, was estimated to occur in about 2% of patients (2). Postulated causes include congenital defects such as Larrey’s cleft, increased intraabdominal pressure caused by obesity or pregnancy, lymphatic drainage disorders, and altered pleuroperitoneal pressure gradients. Individual case reports have described hydrothorax secondary to trauma (3) and to coughing (4); however, none have described iatrogenic causes such as a lung biopsy. Diagnosis of pleuroperitoneal shunts is usually performed via thoracentesis and biochemical analysis (2); the high glucose concentration in the dialysate is diagnostic. Imaging with multidetector CT or nuclear medicine studies can be used to confirm clinical suspicion, evaluate for a likely source of leak, and confirm resolution after treatment (2,5). Treatment strategies may include expectant management and temporary discontinuation of PD to allow the defect to resolve. Recalcitrant cases have been managed with thorascopic and surgical techniques as well as pleurodesis (2). We describe a case of transdiaphragmatic pleuroperitoneal translocation secondary to a left lower lobe lung biopsy representing an unusual cause of post biopsy effusion.