Ralf Langhoff

Nitinol Stent Implantation in TASC A and B Superficial Femoral Artery Lesions: The Femoral Artery Conformexx Trial (FACT)

Purpose: To investigate the impact of nitinol stenting of superficial femoral artery (SFA) lesions with a maximum length of 10 cm (TASC-II A or B) on 1-year outcomes compared to a historical study cohort from the Femoral Artery Stent Trial (FAST). Methods: Between January 2004 and August 2005, 6 study sites enrolled 110 symptomatic patients (75 men; mean age 68±9 years) with a single de novo >70% SFA lesion <10 cm long treated with the self-expanding nitinol Conformexx stent. The primary study endpoint was binary restenosis determined by duplex ultrasound at 12 months. Secondary 12-month endpoints were target lesion revascularization (TLR), ankle-brachial index (ABI), mean Rutherford category, >1-class change in Rutherford category, and major adverse events. Data were analyzed according to the intention-to-treat principle and according to the actual treatment received (“on treatment” analysis). Outcomes were compared to the historical balloon angioplasty (BA) arm and the Luminexx 3 stent arm of the randomized FAST study. Results: Technical success was achieved in 106 (96%) patients; at 1 year, the primary endpoint of ultrasound-assessed binary restenosis was reached in 14 (23.3%) of 60 patients (95% CI 13.4% to 36%). This restenosis rate was lower versus the historical BA (38.6%, p=0.057) or Luminexx 3 stent controls (31.7%, p=0.284) from FAST. The clinically driven TLR was 7.4% (7 of 94 clinically controlled patients), which was also lower compared to 18.3% (p=0.098) and 14.9% (p=0.267) for the historical BA and Luminexx 3 stent groups, respectively. The mean Rutherford category was reduced from 2.75±0.79 to 0.94±1.38 (p<0.0001); 85.1% were improved by at least 1 Rutherford category. The ABI increased from 0.62±0.15 to 0.85±0.20 (p<0.0001). Conclusion: This study of patients with SFA lesions documented favorable outcomes using nitinol stents in TASC-II A or B lesions after 1 year. The study was underpowered to prove superiority of the Conformexx nitinol stent design compared to historical balloon only or Luminexx 3 stent groups.

MISAGO 2: one-year outcomes after implantation of the Misago self-expanding nitinol stent in the superficial femoral and popliteal arteries of 744 patients.

Purpose To evaluate the safety and efficacy of the Misago self-expanding rapid-exchange nitinol stent system for the treatment of femoropopliteal occlusive disease in a prospective multicenter observational trial (ClinicalTrials.gov; identifier NCT01118117). Methods Between April and October 2008, the registry enrolled 744 patients (496 men; 69 ± 10 years) who had symptomatic ≥70% stenosis or occlusion of the superficial femoral or popliteal arteries treated with the Misago stent. Mean length of the 750 lesions was 63.9 mm; 282 (37.6%) vessels were completely occluded. Primary study endpoints were the need for target lesion revascularization (TLR) and event-free survival rates for the assessment of efficacy and safety, respectively. At 6 and 12 months post intervention, clinical symptoms of recurrent ischemia and/or claudication, Rutherford category, and ankle-brachial index (ABI) at rest were assessed. Results In the study period, 945 stents were successfully deployed in the 750 lesions. The overall TLR rate was 10.1% among 671 (90.3%) patients evaluated at 1 year [3.1% among 709 (95.3%) patients at 6 months]. Event-free survival at 12 months was 84.9%. Mean ABIs improved by ≥0.1 in three quarters of the patients (76.0%) over 12 months. The Rutherford grade improved or remained stable in the majority of patients (95.5%) after 1 year. Stent fractures (13 grade 1, 2 grade 2) in 3.1% of stents examined radiographically (n=484) at 1 year were not related to any clinical events. Primary patency was recorded in 574 (87.6%) patients evaluated at 1 year post procedure. Conclusion The Misago rapid-exchange nitinol stent showed promising efficacy and safety results, with a low stent fracture rate, in patients with femoropopliteal disease, making it a safe and reliable treatment option.

The CLEAR-ROAD study: evaluation of a new dual layer micromesh stent system for the carotid artery.

AIMS The aim of this study was to evaluate the 30-day clinical outcome of treatment using the Roadsaver carotid stent in non-consecutive subjects at high risk for carotid endarterectomy requiring revascularisation. METHODS AND RESULTS The CLEAR-ROAD study is a prospective, multinational, single-arm, physician-initiated study planned to include 100 patients in nine centres in Belgium, Italy and Germany. The primary endpoint was the 30-day rate of major adverse events (MAE), defined as the cumulative incidence of any death, stroke or myocardial infarction (MI). The use of embolic protection devices (EPDs) was not mandatory; 31.0% of the patients were symptomatic and in 58.0% of the patients EPDs were used. Technical success was achieved in all cases. The 30-day MAE rate was 2.1% (one patient experienced MI followed by death; another patient experienced a stroke within the first 30 days after procedure). While no statistical analysis could be performed, subgroup data suggested that there were no notable differences in the 30-day MAE rate between symptomatic and asymptomatic patients, or between EPD use. CONCLUSIONS The 30-day clinical outcome of 100 patients treated with a dual layer micromesh carotid stent (Roadsaver) shows promising results. The Roadsaver stent is a safe and effective device for endovascular treatment of subjects at high risk for carotid endarterectomy.

Primary Self-EXPANDing Nitinol Stenting vs Balloon Angioplasty With Optional Bailout Stenting for the Treatment of Infrapopliteal Artery Disease in Patients With Severe Intermittent Claudication or Critical Limb Ischemia (EXPAND Study)

Purpose: To compare primary placement of a self-expanding nitinol stent to percutaneous transluminal angioplasty (PTA) with bailout stenting in infrapopliteal arteries of patients with severe intermittent claudication or critical limb ischemia (CLI). Methods: In the EXPAND trial (ClinicalTrials.gov; identifier NCT00906022), 92 patients (mean age 72.9±9.5 years; 62 men) undergoing treatment for infrapopliteal stenosis in 11 European centers were randomized 1:1 to either self-expanding nitinol stenting with the Astron Pulsar/Pulsar-18 nitinol stent or PTA with bailout stenting. The primary endpoint was sustainable clinical improvement after 12 months, defined as a ≥1-category increase for Rutherford category 3 patients or a ≥2-category increase for CLI patients (Rutherford categories 4/5) compared with baseline. Furthermore, target lesion revascularization (TLR), mortality, and amputation were assessed after 12 months. Results: Sustained clinical improvement at 1 year was observed in 74.3% of the patients treated with primary stenting and in 68.6% of the patients treated with PTA and bailout stenting (p>0.05). Kaplan-Meier estimates of freedom from TLR (76.6% and 77.6%), mortality (7.4% vs 2.1%), and amputation [8.9% (major 6.7%) vs 13.2% (major 8.7%)] at 1 year were not significantly different. Conclusion: Primary self-expanding nitinol stenting did not show statistically different clinical outcomes compared to angioplasty with bailout stenting for infrapopliteal lesions.

MISAGO 1: first-in-man clinical trial with Misago nitinol stent.

AIMS To evaluate a newly developed self-expanding Misago (Terumo Corp., Tokyo, Japan) nitinol stent with rapid exchange delivery catheter for the treatment of stenotic or occluded superficial femoral (SF) or popliteal arteries. METHODS AND RESULTS MISAGO 1 clinical trial enrolled 55 patients undergoing percutaneous intervention of totally occluded or stenotic lesions in SF or popliteal arteries treated with the implantation of 81 stents in five centres across Europe. Primary endpoint was restenosis rate at six months assessed by duplex sonography. Patients (67% male) were 68+/-9 years old, 60% were smokers and 31% had diabetes. Clinical symptoms of ischaemia were present in all patients. Average lesion length was 85+/-50 mm, 64% were totally occluded and 38% classified as TASC C or D. The technical success rate was 100% while the procedural success rate was 98.2% without death, MI, stroke, or major bleeding. At six months follow-up the restenosis rate was 8.5%. One patient (1.8%) died of bronchial carcinoma and two (3.6%) underwent target vessel revascularisation. Mean ankle brachial index improved from 0.70 at baseline to 0.95 at six months while walking capacity on treadmill test improved with an average of 147 m. Rutherford index at six months demonstrated improvement of 72%, without any patients having symptom deterioration. One case of stent fracture was observed. CONCLUSIONS The results from this first-in-man study indicate good safety and short to medium term efficacy profile of the Misago nitinol stent.

Directional Atherectomy Followed by a Paclitaxel-Coated Balloon to Inhibit Restenosis and Maintain Vessel Patency: Twelve-Month Results of the DEFINITIVE AR Study

Background— Studies assessing drug-coated balloons (DCB) for the treatment of femoropopliteal artery disease are encouraging. However, challenging lesions, such as severely calcified, remain difficult to treat with DCB alone. Vessel preparation with directional atherectomy (DA) potentially improves outcomes of DCB. Methods and Results— DEFINITIVE AR study (Directional Atherectomy Followed by a Paclitaxel-Coated Balloon to Inhibit Restenosis and Maintain Vessel Patency—A Pilot Study of Anti-Restenosis Treatment) was a multicenter randomized trial designed to estimate the effect of DA before DCB to facilitate the development of future end point-driven randomized studies. One hundred two patients with claudication or rest pain were randomly assigned 1:1 to DA+DCB (n=48) or DCB alone (n=54), and 19 additional patients with severely calcified lesions were treated with DA+DCB. Mean lesion length was 11.2±4.0 cm for DA+DCB and 9.7±4.1 cm for DCB (P=0.05). Predilation rate was 16.7% for DA+DCB versus 74.1% for DCB; postdilation rate was 6.3% for DA+DCB versus 33.3% for DCB. Technical success was superior for DA+DCB (89.6% versus 64.2%; P=0.004). Overall bail-out stenting rate was 3.7%, and rate of flow-limiting dissections was 19% for DCB and 2% for DA+DCB (P=0.01). One-year primary outcome of angiographic percent diameter stenosis was 33.6±17.7% for DA+DCB versus 36.4±17.6% for DCB (P=0.48), and clinically driven target lesion revascularization was 7.3% for DA+DCB and 8.0% for DCB (P=0.90). Duplex ultrasound patency was 84.6% for DA+DCB, 81.3% for DCB (P=0.78), and 68.8% for calcified lesions. Freedom from major adverse events at 1 year was 89.3% for DA+DCB and 90.0% for DCB (P=0.86). Conclusions— DA+DCB treatment was effective and safe, but the study was not powered to show significant differences between the 2 methods of revascularization in 1-year follow-up. An adequately powered randomized trial is warranted. Clinical Trial Registration— http://www.clinicaltrials.gov. Unique Identifier: NCT01366482.

First clinical experience with the Multi-LOC multiple stent delivery system for focal stenting in long femoro-popliteal lesions

Background: The purpose of this observational study is to report the six-month clinical outcomes with a new multiple stent delivery system in patients with femoro-popliteal lesions. Patients and methods: The LOCOMOTIVE study is an observational multicentre study with a primary endpoint target lesion revascularization (TLR) rate at six months. Femoro-popliteal lesions were prepared with uncoated and/or paclitaxel-coated peripheral balloon catheters. When flow limiting dissections, elastic recoil or recoil due to calcification required stenting, up to six short stents per delivery device, each 13 mm in length, were implanted. Sonographic follow-ups and clinical assessments were scheduled at six months. Results: For this first analysis, a total of 75 patients 72.9 ± 9.2 years of age were enrolled. The majority of the 176 individually treated lesions were in the superficial femoral artery (76.2 %, 134/176) whereas the rate of TASC C/D amounted to 51.1 % (90/176). The total lesion length was 14.5 ± 9.0 cm with reference vessel diameters of 5.6 ± 0.7 mm. Overall 47 ± 18 % of lesion lengths could be saved from stenting. At six months, the patency was 90.7 % (68/75) and all-cause TLR rates were 5.3 % (4/75) in the overall cohort. Conclusions: The first clinical experience at six months suggests that the MSDS strategy was safe and effective to treat femoro-popliteal lesions of considerable length (14.5 ± 9.0 cm). Almost half of the lesion length could be saved from stenting while patency was high and TLR rates were acceptably low.

Credentialing in interventional therapy in Europe – comparison of curricula including endovascular therapy of arterial diseases

The prevalence of peripheral artery disease (PAD) is continuously increasing. In addition, the treatment of PAD has changed substantially over the last decades. Novel treatment modalities and diagnostic tools were developed and endovascular therapy was established as a first-line therapy. In consequence, vascular medicine has become an interdisciplinary field, involving different specialties such as internal medicine/cardiology, internal medicine/angiology, vascular surgery, and (interventional) radiology. Attributed to the expanding field and to ensure high quality and standardized training, various curricula were developed. Not only within the different medical disciplines but across countries. We compared the training programmes in Germany, Switzerland, and Europe and found a great variety in these curricula and programmes. Nevertheless, we identified first attempts to harmonize training requirements within the various societies: the interdisciplinary guidelines of the German Society for Cardiology (DGK) and the German Society of Angiology, the adoption of European standards on a national level, and the Swiss initiative of the Union of Vascular Societies of Switzerland (UVSS). The standard and level of training is high in all curricula and societies. However, further harmonization is needed to optimize patient care and ensure a uniform quality level across different vascular societies.

Stenting bei Carotisstenose

Aktuelle Studiendaten Die 10-Jahresdaten der CREST-Studie (CEA vs. CAS bei symptomatischen und asymptomatischen Karotisstenosen) sowie die 5-Jahresdaten der ACT IStudie (asymptomatische Karotisstenosen) zeigen, dass beide Verfahren hinsichtlich ihres Langzeiterfolges (Schlaganfallverhinderung) vergleichbar und sicher sind. Sowohl die Restenoserate als auch die Reinterventionsraten nach CAS sind gegenüber der CEA nicht signifikant unterschiedlich. Echogenität der Plaques/Nachweis von Mikroembolie In einer Metaanalyse zur Echogenität der Karotissplaques im Ultraschall fanden Jashari et al. heraus, dass Patienten mit echoarmen Plaques ein fast 3fach erhöhtes Risiko für einen Schlaganfall aufweisen als Patienten mit echogenen Plaques. Zusätzliche Information liefert die Detektion von „high intense transient signals“ (HITS) mittels transkranieller Duplexsonografie. Technische Weiterentwicklung von Stents und Protektionsystemen Eine Innovation im Bereich der Protektionssysteme ist der monorail-PTA-Ballon, verbunden mit einem oberhalb des Ballons montierten feinporigen Filtersystem. Die Porengröße beträgt lediglich 40 μm (Standardfilter ≥100 μm) und lässt sich zudem an die benötigten Gefäßdiameter anpassen. Um einer Plaque-Protrusion während des Stentings entgegenzuwirken, haben Micromesh-Stents auf der endoluminalen oder abluminalen Seite des eigentlichen Stentgerüsts ein weiteres feines Netz. Ziel beider Weiterentwicklungen ist die Verhinderung von Minor-Strokes.