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The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock is rising. Acute limb ischaemia remains one of the main complications after ECMO initiation. We analysed 104 patients from our databank from January 2015 to December 2021 who were supported with mobile ECMO therapy. We aimed to identify the impact of acute limb ischaemia on short-term outcomes in patients placed on ECMO in our institution. The main indication for ECMO therapy was left ventricular (LV) failure with cardiogenic shock (57.7%). Diameters of arterial cannulas (p = 0.365) showed no significant differences between both groups. Furthermore, concomitant intra-aortic balloon pump (IABP, p = 0.589) and Impella (p = 0.385) implantation did not differ significantly between both groups. Distal leg perfusion was established in approximately 70% of patients in two groups with no statistically significant difference (p = 0.960). Acute limb ischaemia occurred in 18.3% of cases (n = 19). In-hospital mortality was not significantly different (p = 0.799) in both groups. However, the bleeding rate was significantly higher (p = 0.005) in the limb ischaemia group compared to the no-limb ischaemia group. Therefore, early diagnosis and prevention of acute limb ischaemia might decrease haemorrhage complications in patients during ECMO therapy. [ABSTRACT FROM AUTHOR]

Polyarteritis nodosa (PAN) is a rare form of vasculitis which involves medium and small sized arteries. It can involve any system of the body, but lungs are typically spared. PAN typically presents with non-specific symptoms, such as fever, weight loss and myalgias, and symptoms related to the system involved. Negative serum ANCA helps in differentiating it from other similarly presenting vasculitis and definitive diagnosis is made on histopathology. Limb ischaemia is a rare presentation as well as a rare complication of PAN. We present the case of a 28-year-old female who presented with severe lower limb ischaemia and intermittent leg claudication as initial symptoms which led to initial diagnosis of critical limb ischaemia. Later in the course of the illness she developed gastrointestinal symptoms and weight loss. She was diagnosed as having PAN based on laboratory results and histopathological evidence. Intravenous steroids halted the progress of the disease, but the patient required transmetatarsal amputation of the foot to remove dead tissue. Vasculitis like PAN, although much rarer than atherosclerotic peripheral vascular disease (PVD), should be considered as a differential diagnosis in cases of limb ischaemia in which there is lack of risk factors for PVD. [ABSTRACT FROM AUTHOR]

Objective: Adipose‐derived mesenchymal stem cells (ADSCs) offer great promise as cell therapy for ischaemic diseases. Due to their poor survival in the ischaemic environment, the therapeutic efficacy of ADSCs is still relatively low. Interleukin‐11 (IL‐11) has been shown to play a key role in promoting cell proliferation and protecting cells from oxidative stress injury. The aim of this study was to determine whether IL‐11 could improve therapeutic efficacy of ADSCs in ischaemic diseases. Methods and Results: ADSCs were prepared from inguinal subcutaneous adipose tissue and exposed to hypoxic environment. The protein expression of IL‐11 was decreased after hypoxic treatment. In addition, ADSCs viability was increased after IL‐11 treatment under hypoxia. Moreover, IL‐11 enhanced ADSCs viability in a dose‐dependent manner under normoxia. Importantly, IL‐11 promoted ADSCs proliferation and migration and protected ADSCs against hydrogen peroxide‐induced cellular death. Notably, IL‐11 enhanced ADSCs proliferation and migration, also promoted cell survival and apoptosis resistance by STAT3 signalling. In vivo, mice were subjected to limb ischaemia and treated with IL‐11 overexpression ADSCs and control ADSCs. IL‐11 overexpression ADSCs improved perfusion recovery in the ischaemic muscles. Conclusions: We provide the evidence that IL‐11 promoted ADSCs proliferation, stimulated ADSCs migration and attenuated ADSCs apoptosis by activation of STAT3 signalling. These results suggest that IL‐11 facilitated ADSCs engraftment in ischaemic tissue, thereby enhanced ADSCs therapeutic efficacy. [ABSTRACT FROM AUTHOR]

The presence of distal pulses can be misleading and the presence of good vascularity to the affected part may be unrelated to the possibility of a vascular injury in orthopaedic trauma to the affected part. We report a case of Grade II open fracture of Proximal Tibia with Posterior Tibial Artery (PTA) tear. The case being presented came with an intact PTA pulsations clinically and with good vascularity to the lower limb, with no difference in the pulse rate between radial and posterior tibial pulse rate and no underlying bruits. The underlying PTA tear was found only incidentally on operating when the patient was taken up for open reduction with internal fixation with proximal tibial locking plate surgical procedure and the fracture site was opened. Arterial injuries following trauma may be missed without liberal use of arterial Arteriograms and Doppler study, unless looked for with a high degree of suspicion. If the arterial tear is identified early, patient and his limb can be saved without much morbidity to the patient, though diagnosing the injury is the hard part. Presence of intact and good peripheral pulses is not a sole criteria to rule out underlying vascular injury following orthopaedic trauma. [ABSTRACT FROM AUTHOR]

Objective: This paper evaluates a prototype flat-panel volume CT (fpVCT) for dynamic in vivo imaging in a variety of neurovascular and lower limb applications. Methods: Dynamic CTA was performed on 12 patients (neuro = 8, lower limb = 4) using an fpVCT with 120 kVp, 50 mA, rotation time varying from 8 to 19 s, and field of view of 25 × 25 × 18 cm. Four-dimensional data sets (i.e. 3D images over time) were reconstructed and reviewed. Results: Dynamic CTA demonstrated sufficient spatio-temporal resolution to elucidate first-pass and recirculation dynamics of contrast bolus through neurovasclaur pathologies and phasic blood flow though lower-limb vasculature and grafts. The high spatial resolution of fpVCT resulted in reduced partial volume and metal beam-hardening artefacts. This facilitated assessment of vascular lumen in the presence of calcified plaque and evaluation of fractures, especially in the presence of fixation hardware. Evaluation of arteriovenous malformation using dynamic fpVCT angiography was of limited utility. Conclusions: Dynamic CTA using fpVCT can visualize time-varying phenomena in neuro and lower limb vascular applications and has suffcient diagnostic imaging quality to evaluate a number of pathologies affecting these regions. Key Points: • CTA using fpVCT has sufficient spatial and temporal resolution to study phasic blood flow. • CTA using fpVCT reveals recurrence of aneurysms even after clipping/coiling. • fpVCT has reduced partial volume and metal beam-hardening artefacts. • fpVCT can show vessel lumen in the presence of calcified plaque. • CTA using fpVCT can demonstrate vascular supply to transplanted grafts. [ABSTRACT FROM AUTHOR]

The potential vasodilator effect of the novel compound 2-alkylthio-4-ethyl-4-methyl-4,5 dihydro-1H-imidazolin-5-one oxime (oxime) was investigated in a model of lower limb ischaemia induced in rats by unilateral ligation of the right femoral artery using Laser Doppler Flowmetry. The effect of oxime was compared with that of isoprenaline or L-arginine. Test drugs were injected systemically into the femoral vein or applied locally on the planter surface of the rat hind paw. Serum level of nitrite (NO2 −) and nitrate (NO3 −) were measured by ELISA. Immediately after operative induction of right lower limb ischaemia, blood flow ratio (Right/Left limb ratio: BFR) decreased to 0.33−0.39 in different groups. The intravenous (i.v.) administration of oxime increased BFR in a dose-dependent manner. Compared with pre-drug BFR, oxime administered at doses of 0.064, 0.128 or 0.256 mg/kg increased BFR to 178.8, 328.9 and 705.9 %, respectively. Meanwhile, L-arginine given i.v. at 100 mg/kg increased BFR to 560 %. Isoprenaline given i.v. at 1 μg/kg increased BFR to 274.3 %, while isoprenaline combined with oxime (0.064 mg/kg) increased BFR to 402.7 %. Similarly, after topical application of oxime, BFR increased to 113.5, 261.1 and 433.3 %, respectively. L-arginine given at 1000 mg/kg increased BFR to 389.7 %. Isoprenaline given at 10 μg/kg increased BFR to 231.6 %, while isoprenaline administered in combination with oxime (0.064 mg/kg) increased BFR to 308.3 %. The concentration of NO in serum was significantly increased after systemic or topical administration of either 0.128 and 0.256 mg/kg oxime or 100 and 1,000 mg/kg L-arginine, respectively. It is concluded that systemic or topical oxime results in marked enhancement of blood flow in the rat ischaemic lower limb. This effect of oxime is likely to be mediated through the release of NO. [ABSTRACT FROM AUTHOR]

Objective: To describe 3 cases of vascular injuries due to orthopaedic procedures. Clinical Presentation and Intervention: Of 242 vascular injuries, 3 were due to orthopaedic screws. The 1st patient presented with a late complication (after 3 years) of an orthopaedic screw placed in close proximity to the axillary artery that with time got eroded and leaked to form a false aneurysm which later caused embolisation to the arm and limb ischaemia. The 2nd and 3rd cases were due acute ischaemia following the orthopaedic procedures. Both were injuries to the popliteal artery, one after a long screw and the other after drilling the tibia. The aneurysm of the 1st case was resected, the screw was removed and a reversed segment of the right long saphenous vein was used to repair the axillary artery. In the 2nd patient, a bypass of the left popliteal artery to the tibio-peroneal trunk was performed using a reversed 12-cm-long saphenous vein graft retrieved from the right thigh. In the 3rd patient, the right popliteal vein was ligated, and a reversed 25-cm-long saphenous vein graft retrieved from the left thigh was used for a femoro-popliteal bypass. For the 3 patients, postoperative recovery was unremarkable. Pulses were present within 6-10 months of follow-up. Conclusions: Whenever limb vascularity is compromised after an orthopaedic procedure, a high index of suspicion for an arterial injury should be exercised and prompt referral to the vascular service is mandatory. Repair of injured vessels with a saphenous vein graft provides excellent long-term results. [ABSTRACT FROM AUTHOR]

Rectal cancer and cardiovascular disease are both commoner in the elderly and may coexist. In some severe arteriopaths the blood supply to the lower limbs may be a collateral circulation from the inferior mesenteric artery. Patients with aorto-iliac occlusion or severe stenosis may have collaterals from the inferior mesenteric artery to the lower limb blood vessels. Ligation of the inferior mesenteric artery in treating rectal cancer can result in irreversible ischaemia as outlined in this report. Routine palpation of the femoral pulses and awareness of collateral circulation may avoid the disastrous consequences seen in the two cases described. [ABSTRACT FROM AUTHOR]

Abstract: Different studies have provided evidence that implantation of bone-marrow mononuclear cells (BM-MNC) into ischaemic limbs can improve tissue vascularization. Based on these results we performed a pilot study in patients with critical lower limb ischaemia to assess efficacy and safety of implantation of autologous BM-MNC. The amount and efficacy of BM-MNC purified either by an automated method or by a manual procedure were compared. Twelve patients with severe unilateral lower limb ischaemia were entered into this study. They were randomly assigned to be injected with BM-MNC sorted on a blood cell separator or isolated by density gradient on Ficoll–Hypaque. BM-MNC were implanted into the ischaemic legs. Patients were monitored with resting ankle-brachial pressure index (ABI), arterial oxygen saturation (SaO2), pain-free walking time and rest pain scale evaluation. The automated and manual methods used for mononuclear cell separation gave results not significantly different. Monitored variables improved in both groups. Improvement of ischaemic condition persisted during 24 weeks follow-up. Limb salvage was achieved in five cases. Our results indicate that BM-MNC implantation into ischaemic limbs is a practical, safe and effective method that may significantly contribute to the management of patients with limb ischaemia. The Ficoll method is a simple and effective procedure for BM-MNC concentration that may be useful, mainly in hospitals without sophisticated facilities. [Copyright &y& Elsevier]