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.

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

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.

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.

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.

Multidetector CT angiography of the aortoiliac system and lower extremities: a prospective comparison with digital subtraction angiography.

OBJECTIVE: Our objective was to determine whether multidetector CT (MDCT) angiography is an accurate and reliable method of revealing atheroocclusive disease of the aortoiliac system and the lower extremities compared with digital subtraction angiography (DSA). SUBJECTS AND METHODS: Forty-one patients with ischemic legs underwent both MDCT angiography and DSA of the aortoiliac system and the legs. The arterial supply of the legs was divided into 35 segments. Three independent observers rated each segment according to the maximal degree of arterial stenosis. Consensus interpretation was used to calculate the sensitivity and specificity of MDCT angiography in showing arterial occlusions and stenoses of at least 75%. Intertechnique agreement was measured for each anatomic segment, and interobserver agreement was calculated for both techniques. Agreement was quantified using the kappa statistic. RESULTS: The sensitivity and specificity of MDCT angiography for depicting arterial occlusions and stenoses of at least 75% were 88.6% and 97.7%, and 92.2% and 96.8%, respectively. Substantial intertechnique agreement (kappa > 0.4) was present in 102 (97.1%) of 105 arterial segments. Substantial interobserver agreement was present in 104 (99.0%) of 105 comparisons for both MDCT angiography and DSA with an average kappa value of 0.84 for CT and 0.78 for DSA. MDCT angiography showed more patent segments than DSA (1192 vs 1091). All nine segments seen on DSA and not seen on MDCT angiography were in the calves. Of 110 segments seen on MDCT angiography and not seen on DSA, 100 (90.9%) were in the calves. CONCLUSION: MDCT angiography was accurate in showing arterial atheroocclusive disease with reliability similar to DSA. MDCT angiography showed more vascular segments than DSA, particularly within calf vessels.

V. Uterine fibroid embolization: management of complications.

Fortunately, the number of complications reported after uterine fibroid embolization (UFE) is extremely low. Angiographic mishap or drug reaction are probably more common than purely UFE-related complications. However, the possibility of infection or necrosis of the uterus, with their significant attendant morbidity, is a sobering reminder that embolotherapy can have a powerful impact on the target organ(s). Knowledge of the expected time course for symptom resolution and the often confusing imaging findings shortly after UFE are critical for avoiding unnecessary delay in surgical intervention or, perhaps more important, an inappropriate rush to surgery when antibiotics alone will suffice. Other complications include alteration of uterine physiology, which may disrupt sexual function, and menstrual irregularity and even premature menopause.

IV. Uterine fibroid embolization: follow-up.

Patients generally notice some relief of both menorrhagia and mass-effect symptoms during the first few weeks after uterine fibroid embolization (UFE). Shrinkage of the fibroids continues to take place over several months, peaking somewhere between 3 and 6 months, with measurable shrinkage sometimes noted for up to 1 year. The timing of follow-up visits is intended to coincide with the time course of improvement so that diagnostic imaging and intervention can be performed if symptoms worsen or relief does not appear to be on schedule. The amount of shrinkage of fibroids correlates neither with the intensity of immediate postprocedure symptoms or the degree of symptom relief. Affected fibroids undergo hyaline degeneration, a process in which the hard, cellular tumor is replaced by softer, acellular material. A nationwide registry has been constructed for the accumulation of procedural and follow-up data so that success and complication rates can be accurately determined and long-term issues about the durability of UFE and possible side effects can be addressed.

III. Uterine fibroid embolization: pain management.

Conscious sedation and analgesia are integral components of successful uterine fibroid embolization (UFE), both in providing comfort to the anxious patient undergoing an elective procedure and for providing relief of the severe pelvic pain, cramps, and nausea that may result from acute uterine ischemia and the postembolization syndrome that may follow. The agents used are typically those with which interventional radiologists already have extensive experience in the performance of a variety of invasive procedures. Immediate postprocedure care benefits greatly from the use of narcotic delivered via PCA (patient-controlled analgesia) pump. Nonsteroidal anti-inflammatory drugs (NSAIDs) are also particularly useful for treating the pain and cramping caused by UFE and help reduce the amount of narcotic necessary for pain relief during the recovery period. Detailed instructions for the first week of convalescence are necessary to insure comfort and avoid complications.

Selective spermatic venography and varicocele embolization in men with circumaortic left renal veins.

The presence of variant venous anatomy may increase the technical difficulty of percutaneous varicocele embolization. The authors review their experience performing venography of the left spermatic vein and varicocele embolization in 18 men with circumaortic left renal veins. Selective catheterization of the left spermatic vein was achieved in all but one patient, and all patients with positive venographic results underwent successful embolization. The site of the confluence of the left spermatic vein and the renal vein was variable and it was necessary to use jugular and femoral venous approaches to achieve selective left spermatic vein catheterization. Familiarity with anatomic variations associated with circumaortic renal veins and with embolization techniques from jugular and femoral venous routes facilitates percutaneous varicocele embolization in patients with this variant.

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.