Lindsay Machan

Paclitaxel-Eluting Stents Show Superiority to Balloon Angioplasty and Bare Metal Stents in Femoropopliteal Disease Twelve-Month Zilver PTX Randomized Study Results

Background— Sustained benefits of drug-eluting stents in femoropopliteal arteries have not been demonstrated. This prospective, multinational, randomized study was designed to compare the 12-month safety and effectiveness of a polymer-free, paclitaxel-coated nitinol drug-eluting stent (DES) with percutaneous transluminal angioplasty (PTA) and provisional bare metal stent (BMS) placement in patients with femoropopliteal peripheral artery disease. Methods and Results— Patients were randomly assigned to primary DES implantation (n=236) or PTA (n=238). Demographics and lesion characteristics were similar between groups (eg, average lesion length, approximately 65±40 mm). One hundred twenty patients had acute PTA failure and underwent secondary random assignment to provisional DES (n=61) or BMS (n=59). Primary end points were the 12-month rates of event-free survival and patency in the primary DES and PTA groups. Compared with the PTA group, the primary DES group exhibited superior 12-month event-free survival (90.4% versus 82.6%; P=0.004) and primary patency (83.1% versus 32.8%; P<0.001), satisfying the primary hypotheses. In the secondary evaluations, (1) the primary DES group exhibited superior clinical benefit compared with the PTA group (88.3% versus 75.8%; P<0.001), (2) the provisional DES group exhibited superior primary patency (89.9% versus 73.0%; P=0.01) and superior clinical benefit (90.5% and 72.3%, P=0.009) compared with the provisional BMS group, and (3) the stent fracture rate (both DES and BMS) was 0.9% (4/457). Conclusions— Femoropopliteal peripheral artery disease treatment with the paclitaxel-eluting stent was associated with superior 12-month outcomes compared with PTA and provisional BMS placement. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00120406.

Treatment of Type II Endoleaks with Onyx

Endoleaks are defined as persistent perfusion of an abdominal aortic aneurysm (AAA) after endovascular stent-graft deployment. The authors describe their experience treating six endoleaks with the liquid embolic agent Onyx (ethylene-vinyl-alcohol copolymer). Complete endoleak occlusion was achieved in five of six cases. Follow-up imaging has demonstrated decreased aneurysm diameter in all patients 7-29 weeks (mean = 19.2 weeks) after treatment.

Durable Clinical Effectiveness With Paclitaxel-Eluting Stents in the Femoropopliteal Artery: 5-Year Results of the Zilver PTX Randomized Trial

Background— This randomized controlled trial evaluated clinical durability of Zilver PTX, a paclitaxel-coated drug-eluting stent (DES), for femoropopliteal artery lesions. Outcomes compare primary DES versus percutaneous transluminal angioplasty (PTA), overall DES (primary and provisional) versus standard care (PTA and provisional Zilver bare metal stent [BMS]), and provisional DES versus provisional BMS. Methods and Results— Patients with symptomatic femoropopliteal artery disease were randomly assigned to DES (n=236) or PTA (n=238). Approximately 91% had claudication; 9% had critical limb ischemia. Patients experiencing acute PTA failure underwent secondary randomization to provisional BMS (n=59) or DES (n=61). The 1-year primary end points of event-free survival and patency showed superiority of primary DES in comparison with PTA; these results were sustained through 5 years. Clinical benefit (freedom from persistent or worsening symptoms of ischemia; 79.8% versus 59.3%, P<0.01), patency (66.4% versus 43.4%, P<0.01), and freedom from reintervention (target lesion revascularization, 83.1% versus 67.6%, P<0.01) for the overall DES group were superior to standard care in nonrandomized comparisons. Similarly, clinical benefit (81.8% versus 63.8%, P=0.02), patency (72.4% versus 53.0%, P=0.03), and freedom from target lesion revascularization (84.9% versus 71.6%, P=0.06) with provisional DES were improved over provisional BMS. These results represent >40% relative risk reduction for restenosis and target lesion revascularization through 5 years for the overall DES in comparison with standard care and for provisional DES in comparison with provisional BMS. Conclusions— The 5-year results from this large study provide long-term information previously unavailable regarding endovascular treatment of femoropopliteal artery disease. The Zilver PTX DES provided sustained safety and clinical durability in comparison with standard endovascular treatments. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00120406.

Ciprofloxacin resistance in the faecal carriage of patients undergoing transrectal ultrasound guided prostate biopsy

Transrectal ultrasound guided prostate biopsies (TRUSBx) are associated with a spectrum of complications, including most significantly infection, which affects up to 5% of patients. In the most severe cases, infection leads to sepsis, a life‐threatening complication. Escherichia coli is the primary responsible pathogen. Although antibiotic prophylaxis with fluoroquinolones is routinely used, there is evidence that the infection rate after TRUSBx is increasing, and this appears to be due to an increasing prevalence of ciprofloxacin‐resistant rectal flora. This is the largest prospective clinical trial to date analysing the rectal flora of men undergoing prostate biopsies. We determined the microbial and antibiotic sensitivity profiles from 849 patients. Ciprofloxacin‐resistant Gram‐negative organisms were identified in the rectal flora of 19.0% of men. Furthermore, fluoroquinolone use within 6 months preceding a TRUSBx and the presence of a prosthetic heart valve were significant predictors of ciprofloxacin resistance on rectal swab. Determining the prevalence of rectal fluoroquinolone resistance has important implications in evaluation of the suitability of prophylactic regimens. Antimicrobial profiles derived from rectal swabs pre‐biopsy may prove useful in guiding targeted antibiotic prophylaxis.

A Prospective Randomized Trial of Povidone-Iodine Prophylactic Cleansing of the Rectum Before Transrectal Ultrasound Guided Prostate Biopsy

PURPOSE Transrectal ultrasound guided prostate biopsy can lead to urinary tract infections in 3% to 11% and sepsis in 0.1% to 5% of patients. We investigated the efficacy of rectal cleansing with povidone-iodine before transrectal ultrasound guided prostate biopsy to reduce infectious complications. MATERIALS AND METHODS Between 2009 and 2011, 865 men were prospectively randomized to rectal cleansing (421) or no cleansing (444) before transrectal ultrasound guided prostate biopsy. Patients received ciprofloxacin prophylaxis and rectal swab cultures were obtained before transrectal ultrasound guided prostate biopsy. Patients completed a telephone interview 7 days after undergoing the biopsy. The primary end point was the rate of infectious complications, a composite end point of 1 or more of 1) fever greater than 38.0C, 2) urinary tract infection or 3) sepsis (standardized definition). Chi-square significance testing was performed for differences between groups and a multivariate analysis was performed to assess risk factors for infectious complications. RESULTS Infectious complications were observed in 31 (3.5%) patients, including 11 (2.6%) treated and 20 (4.5%) control patients (p = 0.15). Sepsis was observed in 4 (1.0%) treated and 7 (1.6%) control patients (p = 0.55). On multivariate analysis resistance to ciprofloxacin in the rectal swab culture (p = 0.002) and a history of taking ciprofloxacin in the 3 months preceding transrectal ultrasound guided prostate biopsy (p = 0.009) predicted infectious complications. CONCLUSIONS Rectal cleansing with povidone-iodine before transrectal ultrasound guided prostate biopsy was safe, but the 42% relative risk reduction of infectious complications was not statistically significant. Patients who have received ciprofloxacin within 3 months of transrectal ultrasound guided prostate biopsy should be considered for alternate prophylaxis or possibly a delay of biopsy beyond 3 months.

Preclinical Evaluation of Drug-Eluting Stents for Peripheral Applications Recommendations From an Expert Consensus Group

Drug-eluting stents implanted in the coronary arteries substantially improve long-term outcomes for restenosis. The utility of the stents in peripheral atherosclerosis is under evaluation. Drug-eluting stent evaluation with coronary arteries appears to be an excellent method for evaluating human safety end points. Predicting clinical efficacy remains unclear, however. Because drug-eluting stents are undergoing development for human peripheral arteries, safety and efficacy questions arise in much the same context as they did for the coronary arteries. As they did with the coronary arteries, the clinical, scientific, regulatory, and commercial communities are seeking acceptable criteria for peripheral device evaluation. Substantial differences in stent requirements and biological effects for bare metal peripheral stents depend on implant site. Different anatomic locations under evaluation include femoral, renal, and neurologic arterial stents, and other peripheral applications such as outflow veins of dialysis arteriovenous fistulae are being evaluated. Peripheral in-stent restenosis is less of a problem in carotid and aortoiliac stents and in iliac veins and in the cavae. In general, the benefit:risk ratio for drug-eluting stents may be less for peripheral stents. It is for this reason that peripheral stent performance should be evaluated carefully. This document presents an integrated recommendation set for evaluating drug-eluting stents in peripheral vessels with preclinical models. The recommendations encompass study design, experimental performance, and histopathologic evaluations and emphasize the need to evaluate safety and efficacy at multiple points in time. The present document is a consensus of clinical, academic, and commercial groups—all experts in the evaluation of preclinical investigational or interventional devices. Because preclinical peripheral studies are less well understood than are coronary models, the recommendations do not prescribe a single method for device evaluation; they instead provide broad suggestions for evaluation. Peripheral vascular knowledge will increase as correlations of preclinical with clinical data become available. Future versions of this …

Complete Inhibition of Intimal Hyperplasia by Perivascular Delivery of Paclitaxel in Balloon-injured Rat Carotid Arteries

PURPOSE To determine whether perivascular delivery of paclitaxel prevents luminal narrowing after balloon injury by inhibiting intimal hyperplasia. MATERIALS AND METHODS Immediately after balloon injury of the entire left common carotid artery, three slow-release formulations of paclitaxel or control formulations without drug were applied around a distal segment of the artery. The noninjured right carotid arteries were evaluated as a control. The animals were maintained for 14 and 28 days (n = 5 in each group at each time interval). Histology, immunohistochemistry, and morphometric analysis were performed. RESULTS Injured nontreated arteries exhibited a pronounced intimal hyperplasia (0.185 +/- 0.01 mm2 at 14 days and 0.189 +/- 0.01 mm2 at 28 days) and a marked reduction in luminal area (44% at 14 days and 43% at 28 days). Medial area and the number of medial cells increased by 44% and 45%, respectively, at 14 days, and by 22% and 37%, respectively, at 28 days. Injured arteries treated with perivascular paclitaxel did not show any intimal hyperplasia, and luminal area was increased in five of six groups and was unchanged in one group. These arteries had an increased medial area but they had fewer medial cells than noninjured arteries. Injured arteries treated with control implants without paclitaxel exhibited intimal hyperplasia and luminal narrowing. CONCLUSION Perivascular slow release of paclitaxel totally inhibits intimal hyperplasia and prevents luminal narrowing after balloon injury. Because of its efficacy, perivascular paclitaxel represents a possible approach for prevention of restenosis in humans.

Comparison of MRI and Sonography in the Preliminary Evaluation for Fibroid Embolization

OBJECTIVE The purpose of our study was to evaluate whether pelvic MRI provides additional clinically relevant information after sonography in the preprocedure evaluation of uterine artery embolization of fibroids. MATERIALS AND METHODS Forty-nine women who presented for consultation for uterine artery embolization were retrospectively reviewed. The MRI and sonography scans were independently evaluated and compared for uterine size, fibroid size and location (categorized as paraendometrial, intramural, subserosal, or pedunculated) of the four largest fibroids in each patient, and the total number of fibroids present. RESULTS One hundred twenty-two fibroids were measured. The uterine volume was significantly smaller as measured on MRI compared with sonography (p = 0.01). We found good MRI and sonography correlation of the volume of the single largest fibroid in each patient (R = 0.87) but poor correlation of fibroid location (R = 0.17). MRI detected 31 paraendometrial fibroids and three pedunculated fibroids that were thought to be intramural fibroids on sonography. Five fibroids thought to be paraendometrial on sonography were confirmed to be subserosal or intramural on MRI. Discrepancy in the total number of fibroids was noted, with additional fibroids found on MRI in 31 of 49 patients and erroneously suspected on sonography in five of 49 patients. Pelvic MRI affected management in 11 of 49 patients, leading to cancellation of uterine artery embolization in four patients. In another seven patients who were originally thought to be poor candidates on the basis of sonographic findings, uterine artery embolization was performed. MRI did not alter the management plan in 38 patients. CONCLUSION MRI provided considerable additional information compared with sonography and affected clinical decision making in a substantial number of patients. MRI should be considered in all patients being evaluated for uterine artery embolization.

Self-propelled particles that transport cargo through flowing blood and halt hemorrhage

Simple, water-reactive particles can carry enzymes upstream through aqueous solutions and into wounds to halt severe bleeding. Delivering therapeutics deep into damaged tissue during bleeding is challenging because of the outward flow of blood. When coagulants cannot reach and clot blood at its source, uncontrolled bleeding can occur and increase surgical complications and fatalities. Self-propelling particles have been proposed as a strategy for transporting agents upstream through blood. Many nanoparticle and microparticle systems exhibiting autonomous or collective movement have been developed, but propulsion has not been used successfully in blood or used in vivo to transport therapeutics. We show that simple gas-generating microparticles consisting of carbonate and tranexamic acid traveled through aqueous solutions at velocities of up to 1.5 cm/s and delivered therapeutics millimeters into the vasculature of wounds. The particles transported themselves through a combination of lateral propulsion, buoyant rise, and convection. When loaded with active thrombin, these particles worked effectively as a hemostatic agent and halted severe hemorrhage in multiple animal models of intraoperative and traumatic bleeding. Many medical applications have been suggested for self-propelling particles, and the findings of this study show that the active self-fueled transport of particles can function in vivo to enhance drug delivery.

Repeated Günther Tulip Inferior Vena Cava Filter Repositioning to Prolong Implantation Time

A patient presented with iliofemoral deep vein thrombosis, a small pulmonary embolism, and a paradoxic embolus to the axillary artery resulting from a patent foramen ovale (PFO). As prophylaxis against further paradoxic emboli while awaiting percutaneous PFO closure, a Günther Tulip inferior vena cava (IVC) filter was implanted. To prevent incorporation of the IVC filter into the caval wall, it was repositioned twice with use of a filter retrieval set from a transjugular approach. In this way, the implantation time of the filter was extended beyond the recommended period of 10 days. The filter was successfully retrieved 19 days later during percutaneous closure of the PFO.