Upgrading Monocytes Therapy for Critical Limb Ischemia Patient Treatment: Pre-Clinical and GMP-Validation Aspects.

Advanced cell therapy medicinal products (ATMP) are at the forefront of a new range of biopharmaceuticals. The use of ATMP has evolved and increased in the last decades, representing a new approach to treating diseases that are not effectively managed with conventional treatments. The standard worldwide recognized for drug production is the Good Manufacturing Practices (GMP), widely used in the pharma production of synthesized drugs but applying also to ATMP. GMP guidelines are worldwide recognized standards to manufacture medicinal products to guarantee high quality, safety, and efficacy. In this report, we describe the pre-clinical and the GMP upgrade of peripheral blood mononuclear cell (PBMC) preparation, starting from peripheral blood and ending up with a GMP-grade clinical product ready to be used in patients with critical limb ischemia (CLI). We also evaluated production in hypoxic conditions to increase PBMC functional activity and angiogenic potential. Furthermore, we extensively analyzed the storage and transport conditions of the final product as required by the regulatory body for ATMPs. Altogether, results suggest that the whole manufacturing process can be performed for clinical application. Peripheral blood collected by a physician should be transported at room temperature, and PBMCs should be isolated in a clean room within 8 h of venipuncture. Frozen cells can be stored in nitrogen vapors and thawed for up to 12 months. PBMCs resuspended in 5% human albumin solution should be stored and transported at 4 °C before injection in patients within 24 h to thawing. Hypoxic conditioning of PBMCs should be implemented for clinical application, as it showed a significant enhancement of PBMC functional activity, in particular with increased adhesion, migration, and oxidative stress resistance. We demonstrated the feasibility and the quality of a GMP-enriched suspension of monocytes as an ATMP, tested in a clean room facility for all aspects related to production in respect of all the GMP criteria that allow its use as an ATMP. We think that these results could ease the way to the clinical application of ATMPs.

[Risks and benefits of spirometry in preoperative assessment for the surgical repair of abdominal aortic aneurysm]. / Risques et bénéfices de la spirométrie avant réparation chirurgicale de l'anévrisme de l'aorte abdominale.

Since 2019, spirometry is no longer contraindicated in patients with an aneurysm of the abdominal aorta (AAA). Lung function testing has therefore become a tool for the preoperative morbidity and mortality assessment of patients eligible for surgical repair of AAA. European guidelines of anesthesiology, vascular surgery and pneumology, recommend preoperative spirometry for polymorbide patients, for whom the preoperative assessment must be as complete as possible in order to improve perioperative management and to help specialists decide of the operative mode: open (for patients with a low-risk profile) or endovascular (preferred in high-risk profile patients).

Depuis 2019, la spirométrie n'est plus contre-indiquée chez les personnes porteuses d'un anévrisme de l'aorte abdominale (AAA). Elle peut donc être considérée comme un outil supplémentaire dans le bilan préopératoire des patients candidats à une réparation chirurgicale de l'AAA. Les guidelines européennes de chirurgie vasculaire, de pneumologie et d'anesthésie la recommandent pour les patients polymorbides chez qui l'évaluation du risque péri-opératoire doit être la plus complète possible, afin d'améliorer la prise en charge péri-opératoire et d'aiguiller les spécialistes dans le choix de la technique d'intervention, à abdomen ouvert, pour les patients les plus sains et jeunes (à bas risque), ou par voie endovasculaire, préférée pour les patients âgés et/ou polymorbides (à haut risque).

Computational Analysis of Turbulent Hemodynamics in Radiocephalic Arteriovenous Fistulas to Determine the Best Anastomotic Angles.

BACKGROUND: Hemodynamics has been known to play a major role in the development of intimal hyperplasia leading to arteriovenous fistula failure. The goal of our study is to investigate the influence of different angles of side-to-end radiocephalic anastomosis on the hemodynamic parameters that promote intimal dysfunction and therefore intimal hyperplasia. METHODS: Realistic three-dimensional meshes were reconstructed using ultrasound measurements from distal side-to-end radiocephalic fistulas. The velocity at the proximal and distal radial inflows and at specific locations along the anastomosis and cephalic vein was measured through duplex ultrasound performed by a single examiner. A computational parametric study, virtually changing the inner angle of anastomosis, was performed. For this purpose, we used advanced computational models that include suitable tools to capture the pulsatile and turbulent nature of the blood flow found in arteriovenous fistulas. The results were analyzed in terms of velocity fields, wall shear stress distribution, and oscillatory shear index. RESULTS: Results show that the regions with high oscillatory shear index, which are more prone to the development of hyperplasia, are greater and progressively shift toward the anastomosis area and the proximal vein segment with the decrease of the inner angle of anastomosis. These results are specific to distal radiocephalic fistulas because they are subject to proximal and distal radial inflow. CONCLUSIONS: The results of this study show that inner anastomosis angles approaching 60-70° seem to yield the best hemodynamic conditions for maturation and long-term patency of distal radiocephalic fistulas. Inner angles greater than 90°, representing the smooth loop technique, did not show a clear hemodynamic advantage.

Anastomotic false aneurysm of the aorta: closure with a "sandwiched" coil.

PURPOSE: To describe the treatment of a noninfected saccular anastomotic false aneurysm (AFA) of the abdominal aorta with the use of a single "sandwiched" coil. CASE REPORT: A 65-year-old man presented with a saccular AFA of the distal anastomosis exactly at the level of the aortic bifurcation 1 month after open abdominal aortic aneurysm repair. Endograft exclusion was not attempted because an aortouni-iliac configuration would have sacrificed a patent iliac axis. Coil embolization was the preferred strategy. Use of 3-dimensional rotational angiography and 3-dimensional roadmap was necessary to cannulate the neck of the AFA. Complete thrombosis and shrinkage of the sac was achieved by "sandwich coiling" of the neck after deployment of a single pushable hydrogel-coated coil. Imaging at 9 months postprocedure showed no sign of the aneurysm sac. CONCLUSION: This novel technique can be used for selected saccular AFAs with a narrow neck. In such cases, sandwich coiling may avoid sacrifice of a patent iliac axis.

Ultrasound screening for abdominal aortic aneurysms.

QUESTIONS UNDER STUDY: This pilot study aimed to assess the feasibility, acceptance and costs of an ultrasound scan screening programme for abdominal aortic aneurysms (AAA) in the elderly male population resident in Canton Ticino, Switzerland. METHODS: The target population were male patients aged 65-80 years who attended the outpatient clinics of the Lugano Regional Hospital in 2013. The patients showing interest were contacted by phone to verify their eligibility and fix the appointment for the ultrasound scan of the abdominal aorta. Patients with recent examinations suitable for AAA detection were excluded. Aneurysm was defined as an abdominal aorta with sagittal and/or axial diameter  30 mm. Patients' characteristics and study results were presented as descriptive statistics. The chi-squared test was used to compare categorical variables with p <0.05 as a statistical significance threshold. RESULTS: 1634 patients received the screening information leaflet and 745 (45.6%) underwent the ultrasound scan. Among the 1091 eligible patients, the acceptance rate was 68.3%. A previously unknown AAA was diagnosed in 31 patients (4.2%, 95% confidence interval 2.8-5.9%). Age and area of residence had a statistically significant impact on patient's acceptance rate (p <0.05). The mean cost per screened patient was CHF 88. CONCLUSIONS: AAA screening of male patients aged 65-80 years is feasible with limited financial and organisational effort. Adherence might be improved by a larger community-based programme and involvement of general practitioners.

In-stent restenosis: mid-term results of debulking using excimer laser and drug-eluting balloons: sustained benefit?

BACKGROUND: In-stent restenosis (ISR) after endovascular treatment of stenotic and occlusive disease of the infrainguinal arteries is still a clinical challenge. The purpose of this study is to evaluate the mid-term follow-up of a combination therapy using laser debulking and drug-eluting balloons for ISR. METHODS: A prospective cohort of 14 patients (10 female, 4 male) with clinically relevant (Rutherford 3-6) ISR who were treated with excimer-laser angioplasty and drug-eluting balloons and a clinical follow-up of at least 9 months was evaluated. RESULTS: Mean age was 78 ± 6.5 years (range, 67-88 years). The mean lesion length treated was 133.2 ± 107.2 mm (range, 10-380 mm). The mean time to occurrence of restenosis after initial treatment was 8.6 ± 4.7 months (range, 2-18 months). Technical success was 100%. Distal embolization occurred in 2 cases, and was treated successfully by endovascular means. No other periprocedural major adverse events occurred. All patients were available for clinical follow-up and 12 patients were available with Duplex follow-up. At a mean clinical follow-up of 19.1 ± 8.7 months (range, 9-38 months), 1 target lesion revascularization was seen (at 3 years after the ISR treatment). In the patients with critical limb ischemia (n = 7), no major amputations were needed. Twelve patients had Duplex control (mean follow-up, 19.4 ± 9.4 months; range, 9-38 months). Binary restenosis (>50%) was seen in 1 case at 36 months; it was the same patient who had TLR. A 25%-50% stenosis was seen in 4 patients (mean follow-up, 25 months; range, 19-38 months). No sign of neointimal hyperplasia was demonstrated in 7 patients (mean follow-up, 14.3 months; range, 9-19 months). CONCLUSION: These mid- to long-term data compare favorably with results obtained with standard balloon angioplasty, cutting-balloon angioplasty, and balloon angioplasty using drug-eluting balloon. Longer follow-up and randomized trials are necessary to further define the role of combined excimer-laser debulking and drug-eluting balloon angioplasty in the treatment of ISR.

Effects of probucol versus aspirin and versus brachytherapy on restenosis after femoropopliteal angioplasty: the PAB randomized multicenter trial.

PURPOSE: To evaluate the effect of probucol and/or of endovascular brachytherapy (EVBT) on restenosis after percutaneous transluminal angioplasty (PTA) of femoropopliteal arteries. METHODS: A total of 335 patients (206 men; mean age 72+/-9 years) with intermittent claudication were randomized according to a 2x2 factorial design to 1 of the 4 groups: probucol, placebo, EVBT, and EVBT+probucol. Probucol (1 g/d) or placebo were given in double-blinded fashion 1 month before and for 6 months after PTA. Gamma irradiation (192Iridium, 14 Gy, 5-mm reference depth) was randomly applied in an unblinded manner from a noncentered endoluminal catheter. All patients received aspirin (100 mg/d). Primary endpoint was restenosis (>50% diameter reduction) detected by duplex ultrasound 6 months after PTA. Secondary endpoints included clinical and hemodynamic assessment. RESULTS: Restenosis in patients undergoing EVBT was 17% (23/133) versus 35% (50/142) in patients without EVBT (p<0.001); in patients treated with probucol versus placebo, the rates were 23% (31/135) and 30% (43/140, p<0.001). Three quarters (77%, 102/133) of patients were free of claudication after EVBT therapy versus 61% (87/142) without EVBT (p<0.05). Need for target vessel revascularization was 6% (8/133) with EVBT versus 14% (20/142) without EVBT (p<0.01). Late thrombotic occlusions occurred in 4% (6/133), exclusively in patients treated with EVBT after stent implantation. CONCLUSIONS: Endovascular brachytherapy significantly reduces restenosis, improves symptoms, and reduces reinterventions after PTA of femoropopliteal arteries. Probucol reduces restenosis but has no additive effect when combined with brachytherapy.