Frank C. Lynch

Venous thrombosis associated with the placement of peripherally inserted central catheters.

PURPOSE Peripherally inserted central catheters (PICCs) have become an essential component of the management of an increasing number of patients, including patients who may require hemodialysis. Reported symptomatic venous thrombosis rates associated with PICC lines are based on clinical signs and symptoms and range from 1% to 4%. The purpose of this study is to evaluate the true rate of thrombosis of upper extremity veins after the placement of PICCs and the potential impact on future access in hemodialysis patients. MATERIALS AND METHODS A retrospective analysis was performed. Patients who had (i) normal findings during initial venography, (ii) PICC placement, and (iii) who underwent subsequent repeated venography were included. Age, sex, vein cannulated, catheter size, location, and incidence of thrombosis were analyzed. RESULTS Three hundred fifty-four PICCs were placed in 119 patients. Of the 144 extremities, 137 had normal findings during initial venography. Of the 137 extremities, 32 developed thrombosis of the cannulated vein (or central veins) after initial PICC placement (23.3%). When all extremities with multiple PICC lines placed were considered, 52 developed thrombosis, for an overall thrombosis rate of 38%. The incidence of thrombosis by site was cephalic 57%, basilic 14%, and brachial 10%. No significant differences were noted in the rates of thrombosis by age, sex, or catheter size. CONCLUSIONS There is a relatively high rate of venous thrombosis associated with PICCs, particularly cephalic thrombus. Because of the high rate of thrombosis associated with these catheters, an alternative mode of access should be considered in current or potential hemodialysis patients. All patients with a history of PICC line placement requiring dialysis access should undergo upper extremity venography prior to the placement of permanent access.

A method for following patients with retrievable inferior vena cava filters: results and lessons learned from the first 1,100 patients.

PURPOSE Patients who have undergone implantation of a retrievable inferior vena cava (IVC) filter require continued follow-up to have the device removed when clinically appropriate and in a timely fashion to avoid potential long-term filter-related complications. The efficacy of a method for patient follow-up was evaluated based on a retrospective review of a single-institutional retrievable IVC filter experience. MATERIALS AND METHODS Patients with retrievable IVC filters were tracked via a prospectively collected database designed specifically for patient follow-up. Follow-up consisted of periodic review of the electronic medical record. Patients were contacted by mail (at regular intervals one or more times) when removal of the filter was deemed appropriate. A retrospective review of the ultimate fate of the first 1,127 retrievable IVC filters placed at a single institution was performed. Retrieval rates were compared with those seen in the initial experience, during which no structured follow-up was performed. RESULTS Of 1,127 filters placed, 658 (58.4%) were removed. Filter removal or declaration of the device as permanent was achieved in 860 patients (76.3%). Filter removal, declaration of the device as permanent, or establishment of the need for continued follow-up was achieved in 941 patients (83.5%). Only 186 patients (16.5%) were lost to follow-up. CONCLUSIONS The follow-up method described in the present study resulted in a statistically significant difference (P < .001) in the likelihood of a patient returning for IVC filter removal compared with a lack of follow-up (59% vs 24%).

Fractured Bard Recovery, G2, and G2 Express Inferior Vena Cava Filters: Incidence, Clinical Consequences, and Outcomes of Removal Attempts

PURPOSE To increase the understanding of risks of inferior vena cava (IVC) filter fracture and embolization and the safety of removing fractured filters via retrospective review of a prospectively collected database of fractured IVC filters. MATERIALS AND METHODS A total of 63 fractured IVC filters were discovered among 548 patients presenting for retrievable filter removal between April 2004 and November 2010 at a single institution. Device type, duration of implantation, component fracture, and embolization events were recorded. Success rates and techniques for removal of components were recorded. RESULTS A total of 63 fractured Recovery, G2, and G2 Express IVC filters were identified, for an overall fracture rate of 12%. Excluding foot process fractures, the fracture rate for only filter arms and/or legs was 6%. The incidence of fracture increased with longer filter dwell times. Success rates for removal of the nonfractured component (ie, main body) and fractured components (ie, arm or leg) were 98.4% and 53.4%, respectively. The distal embolization rate of fractured filter components was 13%. There were no immediate clinically significant complications associated with fracture component embolization or filter removal. A single patient was encountered with symptoms related to their fractured filter. CONCLUSIONS IVC filter fracture rates increase with longer dwell times; however, removal of fractured filters and fractured components (ie, arms and legs) can be achieved safely and effectively. Clinically significant complications of IVC filter fracture are rare, and there were no immediate clinical sequelae related to embolization of fracture components.

Technical Success and Safety of Retrieval of the G2 Filter in a Prospective, Multicenter Study

PURPOSE To assess the technical success and safety for retrieval of the G2 filter. MATERIALS AND METHODS The authors performed a prospective, multicenter study of 100 patients with temporary indication for caval interruption. Patients were enrolled consecutively between December 2005 and July 2006. There were 67 men and 33 women with a mean age of 52.1 years (range, 19-82 years). Indications for filter placement were trauma (n = 56), perioperative risk (n = 16), and medical indications (n = 28). Forty-two patients had venous thromboembolism at filter placement. Fifty-eight filters were placed prophylactically. RESULTS Retrieval was attempted in 61 patients. Fifty-eight of the 61 filters (95%) were successfully retrieved after a mean dwell time of 140 days (range, 5-300 days). In all failed retrievals, the filter tip was against the caval wall. There was no difference in dwell times between successful and unsuccessful retrievals. Although there were no cases of cranial migration, caudal migrations were observed in 12% of cases (10 of 85 patients with a complete data set). Other device-related complications included filter fracture (1/85, 1.2%), filter tilt of more than 15 degrees (15/85, 18%), and leg penetration (16/61, 26%). The recurrent pulmonary embolism (PE) rate was 2%, with no PE in the 30-day period after filter retrieval. CONCLUSIONS Retrieval of the Recovery G2 filter was safe and successful in most patients. Caudal migration was observed as an unexpected phenomenon.

Prophylactic inferior vena cava filters: do they make a difference in trauma patients?

BACKGROUND Inferior vena cava filters (IVCF) are used in trauma patients to reduce the incidence of pulmonary embolism (PE). This study investigates the efficacy of prophylactic IVCF (PIVCF) placement from implantation through outpatient follow-up. METHODS Data were prospectively collected on PIVCF placed in trauma patients > or =18-years old from 2004 to 2006. Exclusion criteria include therapeutic IVCF, major burns, deviated from a modified EAST protocol, and deaths. Data were collected on age, gender, Injury Severity Score (ISS), filter type, total implant days, PE, deep venous thrombosis (DVT), and filter-related complications. STATISTICAL ANALYSIS p < 0.05*, chi square test, mean +/- SD. RESULTS Of 4,936 patients, 280 had an IVCF with 244 meeting inclusion criteria. Study group demographics: 63.5% men; 98.8% blunt; mean age 43.8 +/- 20.3; ISS 26.7 +/- 12.8. There were 176 of 244 (72.1%) patients who met traditional EAST guidelines for PIVCF. PIVCF increased significantly from 29 in 2004 to 127 in 2006 with no difference in the PE rate (0.7% to 0.4%). There were 4 PEs (1.6%) on postprocedure days 7, 14, 18, and 23. Five technical complications occurred: two filter fractures, two caudal migrations, and one filter tilt. A total of 140 retrievable filters had the opportunity for outpatient follow-up for 18 months with 58.6% removed, 15.7% declared permanent, 12.1% lost to follow-up, and 13.6% still considered potential removal candidates. Days to implant: 0 to 32; 3.89 +/- 4.79. Implant days: 15 to 838; mean 231 +/- 162. CONCLUSIONS PIVCF increased significantly without impacting the overall PE rate. There was a 1.6% PE rate among PIVCF, high retrieval rate (59%), low complication rate (0.1%), and satisfactory compliance with traditional EAST guidelines.

Balloon-assisted Removal of Tilted Inferior Vena Cava Filters with Embedded Tips

PURPOSE The successful removal of most retrievable inferior vena cava (IVC) filters requires the capture of the filter apex. The severely tilted filter with an apex in contact with the caval wall and covered by an endothelial cap represents a major technical challenge to removal. While a variety of techniques to deal with this problem have been reported, most require complex wire manipulations or the use of rigid endobronchial forceps. This article describes the successful use of a standard angioplasty balloon to free the apex of severely tilted filters with endothelial apical caps. MATERIALS AND METHODS A retrospective review of those patients who presented for removal of their Bard Recovery or G2 IVC filter between June 2005 and August 2008 was performed. Imaging studies and medical records were reviewed for those patients who had their IVC filters removed using the balloon-assisted technique. The presence of filter tilt and movement as well as the outcome of the technique was recorded for each case. RESULTS Forty-eight Recovery and 209 G2 filters presented for removal. Ten of these 257 filters (3.6%) were found to be severely tilted with filter apex embedded into the wall of the cava. Eight of these filters were successfully removed using the balloon-assisted technique. No complications resulting from the technique occurred. CONCLUSIONS Balloon-assisted removal of severely tilted embedded G2 and Recovery filters is an effective technique that can be performed using tools commonly available and familiar to most interventionists.

Comparison of the recovery and G2 filter as retrievable inferior vena cava filters.

PURPOSE To compare the technical success of the Recovery and G2 filters as retrievable inferior vena cava (IVC) filters. MATERIALS AND METHODS Recovery (n = 128) and G2 (n = 113) filters were placed in the IVCs of 241 patients with the intent of retrieval. The referring physician and/or patient were contacted at 6-month intervals to ensure filter retrieval when indicated. The Recovery and G2 filter groups were compared regarding technical success of filter placement, technical success of attempted retrieval, filter tilt, filter migration, filter fracture, and filter efficacy. RESULTS Filter placement was technically successful in 95% of Recovery filters (n = 122) and 100% of G2 filters (n = 113). Recovery filter retrieval was attempted in 55% of patients (n = 71) at a mean of 228 days (range, 0-838 d) after filter placement. G2 filter retrieval was attempted in 55% of patients (n = 62) at a mean of 230 days (range, 7-617 d) after filter placement. Technical success rates of filter retrieval were 94% (n = 67) and 97% (n = 60) in the Recovery and G2 filter groups, respectively. The G2 filter group had significantly fewer cases of (i) filter tilt at placement, (ii) filter tilt at attempted retrieval, and (iii) filter fracture than the Recovery filter group. In the G2 filter group, there was a significantly higher technical success rate of filter placement and there were more cases of caudal filter migration than in the Recovery filter group. CONCLUSIONS Compared with the Recovery filter, the G2 filter is associated with significantly less filter fracture and tilt, greater technical success of filter placement, and more caudal filter migration.

Removal of the G2 Filter: Differences between Implantation Times Greater and Less than 180 Days

PURPOSE To investigate whether filters implanted for longer periods are more difficult or hazardous to remove. MATERIALS AND METHODS A retrospective review of G2 inferior vena cava filter removals was performed. Objective measures reflecting the difficulty of the removal procedure were evaluated for differences required to remove a filter with an implantation period greater or less than 180 days. RESULTS One hundred seventy of 174 G2 filters were successfully removed (97.7% success rate). There was no significant difference in the success rate (P = .86), total procedure time (P = .87), fluoroscopy time (P = .13), or contrast medium use (P = .22) required to remove filters implanted for more than 180 days compared to those implanted for a shorter period of time. There was no significant difference in the frequency of filter movement (P = .90), tilt (P = .87), and caval penetration (P = .41) between the two groups. Six filter fractures were observed, all with implantation times greater than 180 days. CONCLUSIONS The removal of a G2 filter that has been in place for more than 180 days can be performed as easily, as safely, and with a similar degree of success as one that has been in place for less time. Movement, tilt, and penetration are early events after implantation that may have an effect on successful filter removal.

Removal of a Günther Tulip Filter after 3,006 Days

Patients may be denied the opportunity to have their inferior vena cava (IVC) filters removed because of a perception that retrievable filters that have been in place for a long period of time may be more technically difficult or hazardous to remove. A case report on the removal of a Günther Tulip filter that was implanted for a total of 3,006 days is presented. This case report adds to the literature that suggests that no time limits may exist after which many retrievable IVC filters can no longer be safely removed.

The DENALI Trial: An Interim Analysis of a Prospective, Multicenter Study of the Denali Retrievable Inferior Vena Cava Filter

PURPOSE To assess safety and effectiveness of a nitinol retrievable inferior vena cava (IVC) filter in patients who require caval interruption to protect against pulmonary embolism (PE). MATERIALS AND METHODS Two hundred patients with temporary indications for an IVC filter were enrolled in this prospective, multicenter clinical study. Patients undergoing filter implantation were to be followed for 2 years or for 30 days after filter retrieval. At the time of the present interim report, all 200 patients had been enrolled in the study, and 160 had undergone a retrieval attempt or been followed to 6 months with their filter in place. Primary study endpoints included technical and clinical success of filter placement and retrieval. Patients were also evaluated for recurrent PE, new or worsening deep vein thrombosis, and filter migration, fracture, penetration, and tilt. RESULTS Clinical success of placement was achieved in 94.5% of patients (172 of 182), with a one-sided lower limit of the 95% confidence interval of 90.1%. Technical success rate of filter placement was 99.5%. Technical success rate of retrieval was 97.3%; 108 filters were retrieved in 111 attempts. In two cases, the filter apex could not be engaged with a snare, and one device was engaged but could not be removed. Filter retrievals occurred at a mean indwell time of 165 days (range, 5-632 d). There were no instances of filter fracture, migration, or tilt greater than 15° at the time of retrieval or 6-month follow-up. CONCLUSIONS In this interim report, the nitinol retrievable IVC filter provided protection against pulmonary embolism, and the device could be retrieved with a low rate of complications.