Ilkka Uurto

Background and Aims: Treatment of occlusive femoro-popliteal artery disease has changed during the last decade because of intensive development of endovascular technology. The aim of this study was to evaluate patient treated endovascularly or surgically for femoro-popliteal atherosclerotic lesions and to assess perioperative and mid-term outcome. Material and Methods: This is a retrospective analysis of consecutive patients who had undergone prosthetic above-the-knee femoro-popliteal bypass or percutaneous transluminal angioplasty and stenting of superficial femoral artery stenosis or occlusion at Tampere University Hospital, Finland, between January 2007 and December 2009. Patients who were alive were re-evaluated in 2010. Primary and secondary patency and outcomes were assessed. Results: A total of 131 patients were treated; surgically 63 patients (69 procedures) and endovascularly 68 patients (74 procedures). The mean follow-up time was 17 months (SD ± 13 months). In the late follow-up visit, 8 (18%) patients in the bypass group suffered from claudication and 9 (20%) from critical limb ischemia. The corresponding figures for the endovascular group were 20 (36%) and 8 (20%), respectively. The primary patency was 60% at 2 years in the bypass group and 73% in the endovascular group (p = 0.092); the primary assisted patency was 62% versus 76%, respectively (p = 0.068). The secondary patency was 74% in the bypass group versus 79% in the endovascular group (p = 0.487). Conclusions: According to current results following TASC II guideline, satisfied overall mid-term results can be achieved in the treatment of superficial femoral artery atherosclerotic disease.

Varicose veins are a common disorder and many treatment methods are available. The aim of this study was to evaluate the short-term efficacy of foam sclerotherapy and the safety of performing the treatment in an outpatient clinic without ultrasound guidance. METHODS This was a prospective, nonrandomized study with foam sclerotherapy. All the patients were assessed before and after the procedure with a CEAP (Clinical, Etiology, Anatomy, Pathology) class and clinical score. At the same visit, duplex scanning was performed to evaluate the anatomic distribution of the varicose disease. The mean age of the patients was 49.2 years (SD,+/-10.6 years; median, 50.0 years). Altogether 41% of the legs had undergone a previous operation and 24% were recurrences. The follow-up time was 3 months. Twenty-five patients with 27 legs were treated successfully using foam sclerotherapy without ultrasound guidance. Twenty-one cases (78%) involved the great saphenous vein and 6 cases (22%) involved the small saphenous vein. The mean bandage time was 7.7 days (SD,+/-2.50 days; median, 8.50 days). The CEAP score decreased 73% after the procedure from 2.61 (SD,+/-0.80; median, 2.0) to 0.71 (SD,+/-0.95; median, 0; p<.001). and the mean clinical score decreased 45% from 4.45 (SD,+/-1.96; median, 4.0) to 2.46 (SD,+/-1.50; median, 2.0; p<.001), respectively. Three months after the treatment, duplex scanning showed saphenofemoral reflux in 63% of the legs and saphenopopliteal reflux in 40% of the legs. The most common complication was postoperative thrombophlebitis (66%). Other minor complications included pain (38%) and hematoma (4%). There were no major complications. Subjectively, 71% of the patients assessed the procedure as good or excellent and 29% as acceptable or poor. Foam sclerotherapy is also an effective and safe procedure when performed without duplex guidance. Thrombophlebitis is frequent when using a high concentration of polidocanol and a short bandage time. The high frequency of saphenofemoral and saphenopopliteal junction reflux after the procedure can have a negative effect on the long-term results.

Drug-eluting stents are a recent innovation for endovascular and endourethral purposes. The aim of this study was to assess the biocompatibility of new biodegradable drug-eluting stent materials in vivo. Rods made of SR-PLDLA (self-reinforced poly-96l,4d-lactic acid) covered with P(50l/50d)LA and rods made of 96l/4D SR-PLA and covered with P(50l/50d)LA including indomethacin 3.3 μg/mm² or dexamethasone 1.5 μg/mm², were inserted into the dorsal muscles of 20 rabbits serving as test animals. Rods made of silicone and organotin-positive polyvinylchloride were used as negative and positive controls. The animals were sacrificed after 1 week, 1 month, 2 months or 4 months. Histological changes attributable to the operative trauma were seen in all specimens at 1 week and 1 month. At 2 months both dexamethasone and indomethacin induced less fibrosis than the plain SR-PLDLA covered with P(50l/50d)LA without drug. At 4 months dexamethasone induced both chronic inflammatory changes and foreign body reaction, whereas the reactions in the indomethacin and drug-free plain SR-PLDLA groups were insignificant. The new biodegradable drug-eluting stent materials are highly biocompatible. Drug-eluting biodegradable stents may offer a promising new treatment modality for vascular and urethral diseases. However, further studies are needed to demonstrate their feasibility and efficacy.

To evaluate in vivo a new drug-eluting biodegradable vascular stent with respect to biocompatibility, neointimal hyperplasia formation, and reliability. Self-expanding biodegradable poly-96L/4D-lactic acid (PLA) stents with 2 drugs (PLA + dexamethasone [DEX] and PLA + simvastatin [SIM]) and 2 different coatings (PLA + P(D,L)LA and PLA + polycaprolactone [PCL]) were compared with a self-expanding stainless steel Wallstent. The stents were implanted in both common iliac arteries of 8 pigs. Prior to sacrifice at 1 month, angiography was performed to determine patency. Specimens were harvested for quantitative histomorphometry; vascular injury and inflammation scores were assigned to the stented iliac segments. All stented arteries were angiographically patent. The mean luminal diameter (3.05 mm) and area (30.36 mm2) of DEX-eluting PLA stents were decreased compared to other stents (PLA + P(D,L)LA: 3.66 mm and 43.92 mm2; PLA + SIM: 4.21 mm and 56.48 mm2; PLA + PCL: 4.19 mm and 54.64 mm2; Wallstent: 5.01 mm and 81.19 mm2). Wallstents and DEX-eluting PLA stents induced minimal intimal hyperplasia: PLA + DEX: 0.16 mm, PLA + P(D,L)LA: 0.35 mm, PLA + SIM: 0.33 mm, PLA + PCL: 0.29 mm, and Wallstent: 0.18 mm. The vascular injury scores demonstrated only mild vascular trauma for all stents. Only mild to moderate inflammatory reaction was noted around stent struts with a vascular inflammation score. Biodegradable polymer stents appear to be biocompatible and reliable, causing minimal neointimal hyperplasia. Furthermore, the new biodegradable poly-D/L-lactic acid stent can be used as a local drug delivery vehicle. The DEX-eluting PLA stent reduces neointimal hyperplasia. The findings show a need for further investigation to prove the efficacy and safety of this new biodegradable drug-eluting stent.

Purpose: To report results of an in vivo pilot study to evaluate the biocompatibility and delivery system of a new biodegradable vascular stent and validate the study design. Methods: Two self-expanding intravascular stents, a biodegradable poly-D/L-lactic acid (PLA) and a medical stainless steel stent (Wallstent) were implanted in the common iliac arteries of 2 postpuberal female pigs and 3 laboratory-bred beagle dogs. Specimens were harvested after 45 days in the dogs and 32 days in the pigs for histomorphometry of the stented iliac artery segments. Preliminary measurements were made to assess the reliability of the quantitative histomorphometric measurements before final measurements Results: Histomorphometry analyses showed that mean luminal diameter and area were decreased in the PLA stent group (1.97±0.48 mm and 14±6.4 mm², respectively) compared to the control stent group (4.28±0.83 mm and 61±19 mm², respectively). The intimal thickness was higher in the PLA stent group (0.65±0.07 mm) than in the control group (0.44±0.21 mm). The mean injury score was 0.19±0.12 in the PLA stent group and 0.78±0.39 in the controls. In the PLA stent group, the mean inflammation score was 1.46±0.78 compared to 0.58±0.40 in the control group. There were no differences observed between the animal models. Conclusions: The PLA stent showed increased neointimal formation and reduced patency during early follow-up. Mechanical properties of the new biodegradable vascular stents are still inadequate, and the stent and the delivery device require modifications. The study methods were assessed as reliable and reproducible.

Purpose: To assess the reliability of quantitative histomorphometry measurements for the intimal reaction that occurs after intraluminal stenting in an animal model. Methods: Two self-expanding intravascular stents, a biodegradable poly-D/L-lactic acid (PLA) stent and a stainless steel Wallstent, were implanted in the common iliac arteries of a beagle dog. After 45 days, the histomorphometry of the stented iliac artery segments was quantitatively measured. The relative standard error (RSE) of the estimate was calculated, and the reliability of measurements for maximal (LD_max) and minimal (LD_min) luminal diameters and internal (IELT) and external (EELT) elastic lamina thicknesses was assessed. Results: The PLA stent required more measurements of variables from a single slide to ensure reliable (RSEmax, 1 for LD_min, 8 for IELT, and 4 for EELT) compared to the Wallstent (1 for LD_max, 1 for LD_min, 2 for IELT, and 2 for EELT 2). The measured results were reliable for both stent materials when variables were measured from 2 slides of each segment (proximal/central/distal) of the stent. Conclusions: We conclude that these preliminary measurements to estimate the reliability of quantitative histomorphometry measurements should be made and reported before final results are given.