Risk Analysis and Clinical Outcomes in Chronic Limb-threatening Ischemia Patients with Surgical Site Infection after Distal Bypass

BACKGROUND

A recent randomized control study showed that long-term outcomes after surgical revascularization were superior to those after endovascular treatment for cases with chronic limb-threatening ischemia (CLTI) with an appropriate single-segment great saphenous vein. However, surgical site infection (SSI) in CLTI cases after infrapoplital bypass also resulted in a prolonged hospital stay and poor outcomes, including graft disruption. The aim of the current study was to analyze risk factors for SSI in CLTI patients after distal bypass and to compare outcomes in patients with and without SSI.

METHODS

A total of 515 cases that underwent distal bypass at a single center between 2009 and 2022 were analyzed retrospectively. Comparisons were made between patients with and without SSI after distal bypass. The primary end point was limb salvage after distal bypass.

RESULTS

Of the 515 cases that underwent distal bypass, 79 (15%) had SSI. The risk factors for SSI were preoperative antibacterial drug use (P = 0.001), pedal bypass (P = 0.001), and prolonged operation time (≥150 min) (P = 0.010). The median hospital stay in SSI cases was longer than that in non-SSI cases (P < 0.001). Of 515 distal bypasses, 7 (1.3%) bypass grafts ruptured postoperatively due to SSI, and of these 7 cases, 6 ruptured during the day, 5 cases occurred within 1 month postoperatively, and 2 patients (29%) are alive without amputation. The mean follow-up period was 34 ± 30 months. During follow-up, 62 limbs (SSI cases, 19; non-SSI cases, 43) required major amputation and there were 234 deaths (SSI cases, 46; non-SSI cases, 188). The 1-, 3-, and 5-year limb salvage rates of 82%, 71%, and 62%, respectively, in SSI cases were significantly lower than those in non-SSI cases (P < 0.001). The 5-year survival rate of 29% in SSI cases showed a tendency to be lower than that in non-SSI cases (P = 0.058).

CONCLUSIONS

The limb salvage rate in SSI cases was lower than in non-SSI cases after distal bypass. Graft rupture due to SSI occurred at a rate of 1.3% and resulted in poor outcomes in most cases. SSIs adversely affect outcomes and further study is needed to identify methods to avoid SSI following distal bypass.

Endovascular revascularization of critical limb ischemia: the role of ultrasound-guided popliteal sciatic nerve block for the procedural pain management

OBJECTIVES

To evaluate the impact of the ultrasound-guided popliteal sciatic nerve block (PSNB) for pain management during endovascular treatment of chronic limb-threatening ischemia (CLTI).

MATERIAL AND METHODS

From November 2020 to January 2022, 111 CLTI patients that underwent endovascular procedures were prospectively enrolled in this prospective single-arm interventional study. Ultrasound-guided PSNB was used for procedural pain control. Pain intensity was evaluated throughout the procedure (baseline, 10 min after the block, pain peak, and at the end of the procedure) with the visual analog scale (VAS).

RESULTS

Forty-six patients underwent above-the-knee revascularization (ATK), 20/111 below-the-knee (BTK) revascularization, 20/111 to both ATK and BTK revascularization. In 25 cases, no endovascular option was feasible at diagnostic angiography. The PSNB was effective in 96% of patients, with no need for further pain management with a statistically significant reduction (p < 0.0001) in the mean value of the VAS from 7.86 ± 1.81 (pre-procedural) to 2.04 ± 2.20 after 10 min from the block and up to 0.74 ± 1.43 at the end of the procedure (mean time 43 min). Only 1 complication related to the popliteal sciatic nerve block was registered (a temporary foot drop, completely resolved within 48 h). The time necessary to perform the block ranged between 4 and 10 min.

CONCLUSION

Ultrasound-guided PSNB is a feasible and effective method to manage patients with rest pain and increase comfort and compliance during endovascular procedures.

CLINICAL RELEVANCE STATEMENT

An ultrasound-guided popliteal sciatic nerve block is a safe, feasible, and effective technique to manage pain during endovascular treatment of chronic limb-threatening ischemia, especially in frail patients with multiple comorbidities who are poor candidates for deep sedoanalgesia or general anesthesia.

KEY POINTS

Endovascular treatment of CTLI may require long revascularization sessions in patients with high levels of pain at rest, which could be exacerbated during the revascularization procedure. The PSNB is routinely used for anesthesia and analgesia during foot and ankle surgery, but the experience with lower limb revascularization procedures is very limited and not included in any international guideline. Ultrasound-guided PSNB is a feasible and effective regional anesthesia technique to relieve procedural and resting pain. Because of its safety and availability, every interventional radiologist should know how to perform this type of loco-regional anesthesia.

Foot Dorsal and Plantar Flexion to Enhance Crossing of Tortuous Highly-Calcific Ankle Vessels During Lower Limb Revascularization Procedures: A Technical Note

PURPOSE

To describe a crossing technique of stenotic/occluded and tortuous highly calcific ankle vessels during complex percutaneous limb salvage intervention in diabetic patients with ischaemic foot ulcers (Rutherford 5 and 6).

TECHNIQUE

We propose a simple technique to achieve "straightening" of the tortuous vessel and allow safe devices passage into the foot arteries, Patients were asked to hold their foot in plantar or dorsal flexion, accordingly to the treated artery. If unable to do so, an equipe member executed the manoeuvre on their behalf.

RESULTS

The technique was applied in 148 cases, with a success rate of 81% (120/148). No complications related to the manoeuvre were observed.

CONCLUSION

Crossing of tortuous distal crural vessels can be challenging in diabetic patients; in our experience, this technique can be a useful tool to obtain a successful recanalization in complex procedures with high risk of failure.

Effectiveness of the Vascular Quality Initiative Chronic Limb-Threatening Ischemia Mortality Prediction Model in Patents with Distal Bypass

BACKGROUND

The purpose of this study is to evaluate the effectiveness of mortality prediction using the Vascular Quality Initiative (VQI) chronic limb-threatening ischemia (CLTI) model in patients with distal bypass.

METHODS

Patients who underwent distal bypass for CLTI from 2009 to 2020 at a single center were retrospectively reviewed. Distal bypass was defined as any bypass with a distal anastomosis to the posterior tibial, anterior tibial, dorsalis pedis, plantar, or peroneal artery. Baseline characteristics, operative details, hospital outcomes, and medium-term outcomes were compared among patients with a low-, medium-, and high-risk of mortality based on a VQI CLTI calculation. The primary endpoints were survival and limb salvage.

RESULTS

A total of 287 distal bypasses were performed in 230 patients (153 males; median age, 74 years; diabetes mellitus, 70%; end-stage renal disease [ESRD] with hemodialysis, 38%). These patients were stratified into 153 (66%) low-, 35 (15%) medium-, and 42 (18%) high-risk cases based on the VQI CLTI model. There were two hospital deaths (1%) within 30 days. During a mean follow-up period of 33 ± 29 months, 105 patients died and 26 limbs (9%) required major amputation. The 2-year survival rate of 81% in the low-risk group was significantly higher than those of 41% in the medium-risk group and 46% in the high-risk group (both P < 0.001). The 2-year survival rates did not differ significantly between the medium- and high-risk groups (P = 0.81). The 2-year limb salvage rate of 93% in the low-risk group was significantly higher than those of 81% in the medium-risk (P = 0.023) and those of 87% in the high-risk (P = 0.039) groups. There were no significant differences in graft patency and wound healing among the three groups.

CONCLUSIONS

These results suggest that distal bypass is optimal treatment for patients with a low VQI-predicted risk of mortality. However, the lower limb salvage and higher mortality rates at 2 years suggest that the decision-making for VQI medium- and high-risk patients may be carefully considered.

Outcomes of a bypass-first strategy in chronic limb-threatening ischemia based on the Global Vascular Guidelines

OBJECTIVE

The Global Vascular Guidelines (GVGs) recommend initial revascularization (bypass or endovascular therapy) for chronic limb-threatening ischemia (CLTI) based on anatomical complexity and limb severity. This decision is made based on a prediction of the outcomes after endovascular intervention. This study was performed to evaluate outcomes after distal bypass in cases recommended for GVG bypass.

METHODS

A total of 239 distal bypasses for CLTI were evaluated in 195 patients with a GVG bypass recommendation treated between 2009 and 2020 at a single center in Japan. Comparisons were made between crural and pedal bypass cases.

RESULTS

The 195 patients (median age, 77 years; 67% male) underwent 133 crural bypasses (106 patients; 54%) and 106 pedal bypasses (89 patients; 46%). Hemodialysis was more common in pedal cases than in crural cases (P = .03). Hospital deaths occurred in two cases (1%) within 30 days. The whole cohort has a follow-up rate of 96% over a mean of 28 ± 26 months, with 3-year limb salvage rates of 87% and 3-year primary, assisted primary, and secondary patency rates of 40%, 65%, and 67%, all without significant differences between crural and pedal cases. The 1-year wound healing rate was 88% and tended to be higher in crural cases than in pedal cases (P = .068). The 3-year survival rate was 52% in the cohort and did not differ significantly between crural and pedal cases.

CONCLUSIONS

Patients with CLTI with a GVG bypass recommendation had acceptable limb salvage, graft patency, wound healing, and survival after distal bypass, regardless of the bypass method. These findings indicate that a GVG bypass recommendation as an initial revascularization method is valid in the real world.

Endovascular interventions in patients with multilevel steno-occlusive lesions of the infrarenal aortic arteries

Peripheral artery diseases are a worldwide medical and social problem. Approximately 30 % of patients with critical limb ischemia will undergo amputations and 25 % will die after 1 year. These patients require reconstructive and angioplastic interventions to preserve the limb. The aim of the study is to compare the effectiveness of different endovascular surgical technologies in patients with multilevel steno-occlusive lesions of the infrarenal aortic arteries. Materials and methods. Among 243 endovascular interventions, 51 patients were presented with multilevel steno-occlusive lesions of the infrarenal aortic arteries as a result of atherosclerosis obliterans. 42 patients (82.4 %) had two-level lesions and 9 (17.6 %) had three-level lesions. Results. Among 42 patients with a two-level lesion, 29 (56.9 %) ones had femoral arterial segment affection in combination with tibial artery affection. 13 (25.5 %) patients suffered from the lesion of the iliac segment in combination with the affection of the femoral segment arteries. In 9 (17.6 %) patients the lesions of three or more levels were determined: an iliac segment in combination with femoral and popliteal arteries – in 4 patients, and in 2 patients there were lesions of the femoral, popliteal and tibial segments, in 3 patients there was a lesion of the iliac, femoral, popliteal and tibial-foot segments in different degrees of severity. 7 balloon angioplasties and 13 stenting procedures were performed in two and three-level lesions in which the iliac arterial segment was affected. Only balloon angioplasty was used to revascularize the infraingvinal arterial segments. In the early postoperative period, the complications included thrombosis appeared in 6 patients. It was possible to restore the blood flow and save the limb only in 3 persons. For the other 3 ones, the attempts to restore the patency of the arteries were unsuccessful and resulted in the amputation of the lower extremity. Mortality in the early postoperative period was 3.9 % (2 death due to myocardial infarction). Conclusions. The persons with multilevel steno-obstructive lesions of the infrarenal aortic arteries are the most difficult category of patients with CLI. The surgical method of choice for patients with multilevel steno-occlusive lesions is the endovascular angioplasty with or without stenting.

Does the Global Limb Anatomic Staging System Inframalleolar Modifier Influence Long Term Outcomes of Chronic Limb Threatening Ischaemia after Distal Bypass?

OBJECTIVE

The purpose of this study was to evaluate the influence of inframalleolar disease (Global Limb Anatomic Staging System Inframalleolar [GLASS IM] modifier) on long term outcomes of patients with chronic limb threatening ischaemia (CLTI) after distal bypass.

METHODS

Patients who underwent distal bypass for CLTI from January 2012 to December 2019 at a single centre were reviewed retrospectively. Comparisons including baseline characteristics, procedural details, and long term outcomes were made between patients with an intact pedal arch (GLASS IM modifier P0), an absent or severely diseased pedal arch (P1), and no target artery crossing the ankle into the foot (P2), diagnosed by pre- and intra-operative high quality angiography. The primary endpoint was limb salvage. The secondary endpoints were graft patency and wound healing.

RESULTS

A total of 254 distal bypasses were performed in 206 patients (139 males; median age, 76 years). The GLASS IM modifier was P0 in 80 (32%) limbs, P1 in 127 (50%), and P2 in 47 (18%). During the follow up period, 22 limbs (9%) required major amputation. The limb salvage rates at three years in P0, P1, and P2 cases were 94%, 89%, and 93%, respectively, with no significant differences among the modifiers. The primary patencies at three years in P0, P1, and P2 cases were 49%, 38% and 24%, respectively. The primary patency in P2 cases was significantly lower than that in P0 cases (p < .050). The respective wound healing rates at 12 months were 97%, 93%, and 79%, and again the wound healing rate in P2 cases was significantly lower than those in other cases (p < .050).

CONCLUSION

Long term outcomes including patency, limb salvage, and wound healing after distal bypass for CLTI patients with an infrapopliteal lesion were acceptable in cases in each GLASS IM modifier.

Smaller Superficial Femoral Artery is Associated with Worse Outcomes after Percutaneous Transluminal Angioplasty for De Novo Atherosclerotic Disease

BACKGROUND

With the exponential increase in the use of endovascular techniques in the treatment of peripheral artery disease, our understanding of factors that affect intervention failures continues to grow. We sought to assess the outcomes of percutaneous transluminal angioplasty for isolated de novo superficial femoral artery (SFA) disease based on balloon diameter.

METHODS

The Vascular Quality Initiative database was queried for patients undergoing percutaneous balloon angioplasty for isolated de novo atherosclerotic SFA disease. Based on the diameter of the angioplasty balloon as a surrogate measure of arterial diameter, patients were stratified into 2 groups: group 1, balloon diameter <5 mm (354 patients) and group 2, balloon diameter ≥5 mm (1,550 patients). The primary patency and major adverse limb event (MALE) were estimated by the Kaplan-Meier method and compared with the log-rank test, based on vessel diameter. Multivariable Cox regression analysis was used to determine factors associated with the primary patency.

RESULTS

From January 2010 through December 2018, a total of 1,904 patients met criteria for analysis, with a mean follow-up of 13.3 ± 4.5 months. The mean balloon diameters were 3.92 ± 0.26 mm and 5.47 ± 0.55 mm in group 1 and 2, respectively (P < 0.001). The mean length of treatment and distribution of TASC lesions were not statistically different between the groups. Primary patency at 18 months was significantly lower in group 1, compared with group 2 (55% vs. 67%; log-rank P < 0.001). The MALE rate was higher in group 1 than group 2 (33% vs. 26%; log-rank P < 0.001). Among patients with claudication, there was no significant difference in the primary patency (61% vs 68%; log-rank P = 0.073) and MALE (27% vs. 22%; log-rank P = 0.176) at 18 months between groups 1 and 2, respectively. However, in patients with CLTI, group 1 had significantly lower 18-month primary patency (47% vs. 64%; log-rank P < 0.014) and higher MALE rates (41% vs. 35%; log-rank P = 0.012) than group 2. Cox proportional hazard analysis confirmed that balloon diameter < 5 mm was independently associated with increased risks of primary patency loss (HR 1.35; 95% CI, 1.04-1.72; P = 0.021) and MALE (HR 1.29; 95% CI, 1-1.67; P = 0.048) at 18-months.

CONCLUSIONS

In patients undergoing isolated SFA balloon angioplasty for CLTI, smaller SFA (<5 mm) was associated with worse primary patency and MALE. Using balloon size as a surrogate, our findings suggest that patients with a smaller SFA diameter appear to be at increased risk for treatment failure and warrant closer surveillance. Furthermore, these patients may also be considered for alternative approaches, including open revascularization.

Ultrasound-guided puncture reduces bleeding-associated complications, regardless of calcified plaque, after endovascular treatment of femoropopliteal lesions, especially using the antegrade procedure: A single-center study

Background

A common complication of endovascular treatment for femoropopliteal lesions is bleeding at the vascular access site. Although risk factors of bleeding-associated complications at the approach site have been reported, the results have been inconclusive. Hence, this study aimed to assess the predictors of bleeding-associated complications at the approach site in patients undergoing endovascular treatment for femoropopliteal lesions.

Methods

This retrospective, single-center, observational study included consecutive patients who underwent endovascular treatment (n = 366, 75% male, 72.4±9.9 year) for peripheral arterial disease with claudication and critical limb ischemia in our hospital from January 2010 to December 2017. We divided the patients into bleeding and non-bleeding groups, depending on whether bleeding-associated complications occurred at the approach site. Bleeding-associated complications were defined according to the Bleeding Academic Research Consortium criteria types 2, 3, and 5.

Results

Altogether, 366 endovascular treatment procedures and 404 arterial accesses were performed for femoropopliteal lesions in 335 peripheral arterial disease patients with claudication and 69 critical limb ischemia patients. We recorded 35 postprocedural bleeding-associated complications at the approach site (9%), all of which were hematomas. The predictors of increased bleeding-associated complications were age ≥ 80 years (bleeding vs. non-bleeding group, 43% vs. 25%, p<0.05) and antegrade cannulation of the common femoral artery (48% vs. 69%, p<0.05). Ultrasound-guided puncture reduced bleeding-associated complications (odds ratio, 0.28; 95% confidence interval, 0.004–0.21; p<0.05). In contrast, there was no significant difference in puncture site calcification between the groups (bleeding vs. non-bleeding groups, 29% vs. 21%, p = 0.29).

Conclusion

Ultrasound-guided puncture is associated with a decrease in bleeding-associated complications at the approach site, regardless of the presence of calcified plaque. It is particularly effective and should be more actively used in patients aged ≥80 years and for antegrade cannulation of the common femoral artery.

Lower extremity revascularization via endovascular and surgical approaches: A systematic review with emphasis on combined inflow and outflow revascularization

This review is intended to help clinicians and patients understand the present state of peripheral artery disease, appreciate the progression and presentation of critical limb ischemia/chronic limb-threatening ischemia, and make informed decisions regarding inflow and outflow endovascular revascularization and surgical treatment options within the context of current debates in the medical community. A controlled literature search was performed to obtain research on outcomes of critical limb ischemia patients undergoing complete leg revascularization for peripheral artery disease inflow and outflow disease. Data for this review were identified by queries of medical and life science databases, expert referral, and references from relevant papers published between 1997 and 2019, resulting in 48 articles. The literature review herein indicates that endovascular revascularization-including ballooning, stenting, and atherectomy-is an effective peripheral artery disease therapy for both above the knee and below the knee disease, and can safely and effectively treat both inflow and outflow disease. As such, it plays a leading role in the therapy of lower extremity artery disease.

Feasibility of a circulation model for the assessment of endovascular recanalization procedures and periprocedural thromboembolism in-vitro

Aim of this study was to establish a simple and highly reproducible physiological circulation model to investigate endovascular device performance. The developed circulation model included a pneumatically driven pulsatile pump to generate a flow rate of 2.7 L/min at 70 beats per minute. Sections from the superficial femoral arteries were used in order to simulate device/tissue interaction and a filter was integrated to analyze periinterventional thromboembolism of white, red and mixed thrombi. The working fluid (3 L) was a crystalloid solution constantly tempered at 36.5 °C. To evaluate the model, aspiration thrombectomy, stent-implantation and thrombectomy with the Fogarty catheter were performed. Usability of the model was measured by the System Usability Scale (SUS) – Score. Histological specimens were prepared and analyzed postinterventional to quantify tissue/device interaction. Moreover, micro- and macroembolism were evaluated for each thrombus entity and each device. Results were tested for normality using the D’Agostino-Pearson test. Statistical comparisons of two groups were performed using the Student’s t-test. All devices were able to remove the occlusions after a maximum of 2 attempts. First-pass-recanalization was not fully achieved for aspiration thrombectomy of mixed thrombi (90.6%), aspiration thrombectomy of red thrombi (84.4%) and stent-implantation in occlusions of red thrombi (92.2%). Most micro- and macroembolism were observed using the Fogarty catheter and after stent-implantation in occlusions of white thrombi. Histological examinations revealed a significant reduction of the vascular layers suggesting vascular damage after use of the Fogarty catheter (327.3 ± 3.5 μm vs. 440.6 ± 3.9 μm; p = 0.026). Analysis of SUS rendered a mean SUS-Score of 80.4 which corresponds to an excellent user acceptability of the model. In conclusion, we describe a stable, easy to handle and reproducible physiological circulation model for the simulation of endovascular thrombectomy including device performance and thromboembolism.

The relationship between plaque cap morphology and access technique in lower extremity chronic total occlusion

OBJECTIVES

To evaluate access success according to plaque cap morphology in subjects with lower limb chronic total occlusion.

METHODS

A retrospective study was performed for a three-year period. Subjects with lower extremity chronic total occlusion (Rutherford category 3-6, ischaemia) were included in the study. Cap morphology was classified according to The chronic total occlusion crossing approach based on plaque cap morphology (CTOP) classification system. When describing the classification by a traditional antegrade approach, Types I, II, III and IV were defined as follows: Type I: concave proximal and distal caps; Type II: concave proximal and convex distal caps; Type III: convex proximal and concave distal caps; Type IV: convex proximal and distal caps. For the study, the data on demographics, access type, and direction crossed, access conversion, crossing success, crossing location, extravascular ultrasound guidance, catheter used, subjects, and localization of were recorded. The effect of cap morphology on crossing strategy and success was evaluated.

RESULTS

A total of 110 subjects were enrolled in this study. The type of chronic total occlusion was determined by angiography in 100% of the subjects. The number of the subjects according to CTOP morphology for Types I, II, III and IV were 22 (20%), 39 (35.5%), 23 (20.9%) and 26 (23.6%), respectively. Superficial femoral artery, popliteal, anterior tibial, posterior tibial localizations did not differ among the CTOP types ( p = 0.649, p = 0.831, p = 0.923 and p = 0.903, respectively). Among the pre-operation parameters, lesion length was the only one that is significantly shorter in Type I (14.23 ± 1.93 cm) subjects when compared with Types II (21.77 ± 3.78 cm), III (21.17 ± 2.31 cm) and IV (19.85 ± 3.29 cm) subjects ( p < 0.001, for all comparisons). Antegrade access was significantly higher in group I than in group III. Planned dual access was also significantly lower in CTOP Type I than in CTOP Types II, III and IV. Antegrade crossed direction was significantly higher in CTOP Type I than in CTOP Types II, III and IV ( p = 0.001, for all comparisons). True lumen crossing was significantly higher in CTOP Type I than in CTOP Type II ( p = 0.002). In univariate analysis, chronic total occlusion Type IV was the only significant factor for antegrade crossing ( p = 0.001). Multivariate analysis demonstrated that chronic total occlusion Type IV (OR = 0.09, p = 0.001) was an independent risk factor for antegrade crossing. The odds of antegrade crossing for chronic total occlusion Type IV was 0.190 times that of chronic total occlusion Types I-II-III combined (OR (95% CI): 0.190 (0.070, 0.519), p = 0.001).

CONCLUSIONS

CTOP Type I accesses with an antegrade access, and Type IV accesses with a retrograde strategy. Type II and Type III CTOP will need planned dual access in order to prevent device bending and subintimal access.

Arterial Recanalization for Access for Arterial Intervention in Children: Techniques and Outcomes

PURPOSE

To assess technical success of arterial recanalization in children requiring repeated arterial access and intervention.

MATERIALS AND METHODS

Over 14 years, 41 attempts to cross 30 arterial occlusions were made in 22 patients (13 male, 9 female). Median patient age was 12 months (15 days-14 years), and weight was 7.6 kg (3.0-77.3 kg). Techniques and outcomes were recorded.

RESULTS

Twenty-five of 41 (61%) attempts at crossing an arterial occlusion were successful. Nineteen of 30 (63%) first attempts to cross occlusions were successful, and 6 of 11 (55%) repeat attempts were successful. The occluded segments were combinations of common femoral artery (n = 4), external iliac artery (n = 36), common iliac artery (n = 11), and aorta (n = 1). Complications occurred in 5 of 41(12%) attempts: 3 minor complications (hematoma, extravasation, and transient leg ischemia) and 2 major complications (rupture and thrombosis).

CONCLUSIONS

Arterial access by recanalization of occluded segments is technically feasible in children, with a low complication rate.

Pilot Cohort Study Assessing the Efficacy of Endovascular Revascularization in the Restoration of Peripheral Sensory Disturbance in Patients With Critical Limb Ischemia

BACKGROUND

Sensory disturbance (SD) is a common consequence of peripheral nerve damage associated with diabetes and severe ischemia. Progression of SD places patients at high risk for lower extremity ulcers and amputations. SD has been thought to be progressive and irreversible, and possibly caused by microvascular dysfunction. The aim of this study was to determine whether endovascular revascularization (EVR) induces quantifiable changes in SD in chronic critical limb ischemia (CLI) patients with neuropathy.Methods and Results:In all, 36 legs from 28 chronic CLI patients who underwent elective EVR were prospectively enrolled in this study (64% with diabetes and 54% on maintenance hemodialysis). The current perception threshold (CPT), an established diagnostic parameter for SD, was measured before and 3 months after EVR. Of the target lesions, 11%, 47%, and 81% were in the aortoiliac, femoropopliteal, and below-the-knee arteries, respectively, and 58% were totally occluded. Overall CPT in the target foot had improved significantly 3 months after EVR (from 53 to 30 µA; P=0.010); however, EVR did not change CPT in the non-target foot (from 44 to 33 µA; P=0.33). Patients with improved SD after EVR had a significantly higher 180-day survival rate (94% vs. 63%; P=0.040).

CONCLUSIONS

EVR improved CPT in target limbs of patients with CLI, and may be a promising option to improve SD associated with peripheral ischemic sensory neuropathy.

Robotics in percutaneous cardiovascular interventions

INTRODUCTION

The fundamental technique of performing percutaneous cardiovascular (CV) interventions has remained unchanged and requires operators to wear heavy lead aprons to minimize exposure to ionizing radiation. Robotic technology is now being utilized in interventional cardiology partially as a direct result of the increasing appreciation of the long-term occupational hazards of the field. This review was undertaken to report the clinical outcomes of percutaneous robotic coronary and peripheral vascular interventions. Areas covered: A systematic literature review of percutaneous robotic CV interventions was undertaken. The safety and feasibility of percutaneous robotically-assisted CV interventions has been validated in simple to complex coronary disease, and iliofemoral disease. Studies have shown that robotically-assisted PCI significantly reduces operator exposure to harmful ionizing radiation without compromising procedural success or clinical efficacy. In addition to the operator benefits, robotically-assisted intervention has the potential for patient advantages by allowing more accurate lesion length measurement, precise stent placement and lower patient radiation exposure. However, further investigation is required to fully elucidate these potential benefits. Expert commentary: Incremental improvement in robotic technology and telecommunications would enable treatment of an even broader patient population, and potentially provide remote robotic PCI.

The Development of Robotic Technology in Cardiac and Vascular Interventions

Robotic technology has been used in cardiovascular medicine for over a decade, and over that period its use has been expanded to interventional cardiology and percutaneous coronary and peripheral vascular interventions. The safety and feasibility of robotically assisted interventions has been demonstrated in multiple studies ranging from simple to complex coronary lesions, and in the treatment of iliofemoral and infrapopliteal disease. These studies have shown a reduction in operator exposure to harmful ionizing radiation, and the use of robotics has the intuitive benefit of alleviating the occupational hazard of operator orthopedic injuries. In addition to the interventional operator benefits, robotically assisted intervention has the potential to also be beneficial for patients by allowing more accurate lesion length measurement, stent placement, and patient radiation exposure; however, more investigation is required to elucidate these benefits fully.

The effect of LED on blood microcirculation during chronic wound healing in diabetic and non-diabetic patients-a prospective, double-blind randomized study

Chronic wounds, especially in diabetic patients, represent a challenging health issue. Since standard treatment protocols often do not provide satisfactory results, additional treatment methods-like phototherapy using low-level light therapy-are being investigated. The aim of our study was to evaluate the effect of phototherapy with light-emitting diodes on chronic wound treatment in diabetic and non-diabetic patients. Since a sufficient blood supply is mandatory for wound healing, the evaluation of microcirculation in the healthy skin at a wound's edge was the main outcome measure. Forty non-diabetic patients and 39 diabetics with lower limb chronic wounds who were referred to the University Medical Center Ljubljana between October 2012 and June 2014 were randomized to the treated and control groups. The treated group received phototherapy with LED 2.4 J/cm² (wavelengths 625, 660, 850 nm) three times a week for 8 weeks, and the control group received phototherapy with broadband 580-900 nm and power density 0.72 J/cm². Microcirculation was measured using laser Doppler. A significant increase in blood flow was noted in the treated group of diabetic and non-diabetic patients (p = 0.040 and p = 0.033), while there was no difference in the control groups. Additional Falanga wound bed score evaluation showed a significant improvement in both treated groups as compared to the control group. According to our results, phototherapy with LED was shown to be an effective additional treatment method for chronic wounds in diabetic and non-diabetic patients.

Endovascular revascularization of TASC C and D femoropopliteal occlusive disease using carbon dioxide as contrast

Objective

To analyze the results of ten angioplasties of TASC C and D femoropopliteal lesions using CO₂ as primary contrast in patients with no formal contraindication to iodine, aiming to decrease allergic reactions and potential nephrotoxicity in high-risk patients.

Methods

We describe the results of ten angioplasties of TASC C and D femoropopliteal lesions using CO₂ as primary contrast in patients with high risk for open revascularization and no formal contraindication to iodine. We analyzed feasibility of the procedures, complications, quality of the angiographic images, clinical and surgical outcomes, and costs of C and D lesions treated using CO₂ as contrast medium.

Results

The use of CO₂ in C and D lesions needed iodine complementation in most of the cases (nine cases) but decreased the potential nephrotoxicity of iodine contrast medium by the reduction of its volume in this group of high-risk patients. The extension of the arterial lesions was the factor that most contributed to the need for iodine supplementation due to the difficulty to visualize the refill after a long arterial occlusion.

Conclusion

The use of CO₂ as contrast in patients with C and D lesions with no restriction for iodine contrast medium was an alternative that did not dismiss the need of iodine supplementation in most of the cases, but could decrease the potential nephrotoxicity of iodine constrast medium.

Dynamic imaging of allogeneic adipose-derived regenerative cells transplanted in ischemic hind limb of apolipoprotein E mouse model

Background

Transplantation of allogeneic adipose-derived regenerative cells (ADRCs) is a promising treatment modality for severe ischemic diseases. However, minimal information is available on the in vivo effects, fate, and migration of ADRCs, as well as the mechanisms of their therapeutic angiogenesis.

Materials and methods

In this study, green fluorescent protein-expressing ADRCs (GFP-ADRCs) were obtained, labeled with acetylated 3-aminopropyltrimethoxysilane (APTS)-coated iron oxide nanoparticles (APTS NPs), and injected into an old apolipoprotein E knockout (ApoE-KO) mouse model with hind limb ischemia. Then, 3.0 T magnetic resonance imaging (MRI) was performed to dynamically trace the role of ADRCs targeting hind limb ischemia in the ApoE-KO mice model.

Results

Labeled cells were visualized as large hypointense spots in ischemic muscles by serial 3.0 T MRI scans during a 4-week follow-up. The presence of labeled GFP-ADRCs was confirmed by Prussian blue staining and fluorescence microscopy on postmortem specimens.

Conclusion

This study showed that allogeneic ADRCs offer great potential application for therapeutic angiogenesis in severe ischemic disease based on the efficacy and feasibility of ADRC transplantation and on the available amounts of tissue.