Complicated retroperitoneal diverticulitis presenting with abscess and acute limb ischemia.

This case highlights a rare presentation of diverticulitis of the sigmoid colon with perforation into the retroperitoneum complicated by abscess, vertebral osteomyelitis and acute lower extremity ischemia. A late 40-year-old man presented to an emergency department with acute ischemia of his left lower extremity. He was tachycardic with a leucocytosis, an unremarkable abdominal exam and a pulseless, insensate and paralysed left lower extremity. Imaging revealed sigmoid thickening, an abscess adjacent to iliac vasculature and occlusion of the left popliteal artery. The abscess came in contact with prior spine anterior lumbar interbody fusion (ALIF) hardware at L5-S1 vertebrae. The patient was taken urgently to the operating room for embolectomy, thrombectomy and fasciotomy. He was started on antibiotics and later underwent operative drainage with debridement for osteomyelitis. Non-operative management of the complicated diverticulitis failed, necessitating open sigmoidectomy with colostomy. 1 year later, he was symptom-free and the colostomy was reversed.

[Value of serum levels in predicting lower extremity deep vein thrombosis after hip joint surgery in the elderly].

OBJECTIVE: To explore the value of serum D-dimer (D-D), fibrinogen (FIB), platelet (PLT), C-reactive protein (CRP) and tissue plasminogen activator inhibitor (PAI)-1 levels in predicting lower extremity deep vein thrombosis (DVT) after hip joint surgery in the elderly. METHODS: A retrospective analysis was performed on 165 elderly patients with hip joint surgery admitted from February 2020 to May 2022, including 89 males and 76 females, aged from 60 to 75 years old with an average of (66.43±5.48) years, and there were 102 cases of femoral neck fracture and 63 cases of femoral head necrosis. Serum levels of D-D, FIB, PLT, CRP and PAI-1 tests were performed in all patients within 24 hours after admission, and the patients were divided into DVT group and non-DVT group according to whether they developed DVT. RESULTS: The levels of D-D, FIB, PLT, CRP, and PAI-1 in the DVT group were higher than those in the non-DVT group (P<0.001). Spearman analysis showed that DVT was positively correlated with PLT, CRP, D-D, FIB, and PAI-1 levels (r=0.382, 0.213, 0.410, 0.310, 0.353, all P<0.001). The results of binary Logistic regression analysis showed that D-D and PLT were independent factors affecting the occurrence of DVT (OR=0.038, 0.960, P=0.032, 0.011). The area under curve (AUC) of D-D, FIB, PLT, CRP, PAI-1, and the five combined predictions for DVT were 0.843, 0.692, 0.871, 0.780, 0.819, and 0.960, respectively. The AUC of the five combined predictions was higher than that of the single prediction (P<0.05). CONCLUSION: D-D, FIB, PLT, CRP and PAI-1 are effective in predicting DVT after hip surgery in the elderly, and the combined prediction of the five factors has higher efficacy.

CCCTC-binding factor suppresses alpha-2-macroglobulin transcription to improve vascular endothelial cell functions in lower extremity arteriosclerosis obliterans.

Vascular endothelial cell functions affect lower extremity arteriosclerosis obliterans (LEASO), while alpha-2-macroglobulin (A2M) and CCCTC-binding factor (CTCF) are closely related to the function of such cells. This paper aims to identify the influences of CTCF on vascular endothelial cells in LEASO by regulating A2M. A rat model of LEASO was established to measure intima-media ratio, blood lipid, and inflammatory factor levels. By constructing LEASO cell models, cell viability and apoptosis were assayed, while autophagy-related proteins, CTCF and A2M levels in femoral artery tissues and HUVECs were determined. The transcriptional regulation of CTCF on A2M was verified. In LEASO rat models, femoral artery lumen was narrowed and endothelial cells were disordered; levels of total cholesterol, IL-1, and TNF-α enhanced, and HDL-C decreased, with strong expression of A2M and low expression of CTCF. The viability of ox-LDL-treated HUVECs was decreased, together with higher apoptosis, lower LC3II/I expression, and higher p62 expression, which were reversed by sh-A2M transfection. Overexpression of CTCF inhibited A2M transcription, promoted the viability and autophagy of HUVECs, and decreased apoptosis. Collectively, CTCF improves the function of vascular endothelial cells in LEASO by inhibiting A2M transcription.

Comparison of efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism in lower extremities after total hip arthroplasty and total knee arthroplasty: a retrospective study of 592 patients.

OBJECTIVES: To compare the efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism (DVT) in lower extremities after total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: A total of 592 patients were enrolled in the study. Clinical data of patients who underwent total hip arthroplasty (THA) and total knee arthroplasty (TKA) in our hospital from December 2021 to September 2022 were retrospectively collected, which mainly included patients' general information, surgery-related information, and DVT-related information. The patients were categorized into the nadroparin group(n = 278) and the fondaparinux sodium group(n = 314) according to the types of anticoagulants used. Anticoagulant therapy began 12-24 h after operation and continued until discharge. DVT prevalence between two groups was compared. The Statistical Package for Social Sciences (SPSS) software version 25 (SPSS, Armonk, NY, USA) was used for statistical analysis. RESULTS: The prevalence of DVT in the nadroparin group and the fondaparinux sodium group was 8.3% (23/278) and 15.0% (47/314), respectively(p = 0.012). Statistical analysis showed that nadroparin group showed a lower prevalence of thrombosis than fondaparinux group (OR = 1.952, P = 0.012). Subgroup analyses showed that nadroparin group had a lower prevalence of DVT than fondaparinux group in some special patients groups such as female patients (OR = 2.258, P = 0.007), patients who are 65-79 years old (OR = 2.796, P = 0.004), patients with hypertension (OR = 2.237, P = 0.042), patients who underwent TKA (OR = 2.091, P = 0.011), and patients who underwent combined spinal-epidural anesthesia (OR = 2.490, P = 0.003) (P < 0.05). CONCLUSION: Nadroparin may have an advantage over fondaparinux sodium in preventing DVT in lower extremities after THA and TKA.

Retrospective Evaluation of the Effect of Lumbar Sympathetic Blockade on Pain Scores, Fontaine Classification, and Collateral Perfusion Status in Patients with Lower Extremity Peripheral Arterial Disease.

Background and Objectives: The aim of this retrospective study was to evaluate the effect of lumbar sympathetic block (LSB) on pain scores, Fontaine Classification, and collateral perfusion status in patients with lower extremity peripheral artery disease (PAD), in whom revascularization is impossible. Material and Methods: Medical records of 21 patients with PAD who underwent LSB with a combination of local anesthetics, steroids, and patient follow-up forms containing six-month follow-ups between January 2020 and March 2021 were retrospectively reviewed. Numeric Rating Scale (NRS), Pain Detect Questionnaire (PDQ) scores, Fontaine Classification Stages, and collateral perfusion status (collateral diameter and/or development of neovascularization) evaluated by arterial color Doppler Ultrasound (US) from the medical records and follow-up forms of the patients were reviewed. Results: NRS and PDQ scores were significantly lower, and regression of the Fontaine Classification Stages was significantly better after the procedure at the first, third, and sixth month than at the baseline values (p < 0.001). Only four patients (19%) had collaterals before the procedure. An increase in the collateral diameter after LSB was noted in three out of four patients. Before the procedure, 17 patients had no prominent collateral. However, in thirteen of these patients, after LSB, neovascularization was detected during the six-month follow-up period (three patients in the first month, seven patients in the third month, and thirteen patients in the sixth month). The number of patients evolving neovascularization after LSB was found to be statistically significant at the third and sixth months compared to the initial examination (p < 0.001). Conclusions: LSB with the use of local anesthetic and steroids in patients with lower extremity PAD not only led to lower NRS and PDQ scores, but also resulted in regressed Fontaine Classification Stages and better collateral perfusion status.

Development and validation of a risk prediction model and prediction tools for post-thrombotic syndrome in patients with lower limb deep vein thrombosis.

PURPOSE: Our research aims to compare the predictive performance of decision tree algorithms (DT) and logistic regression analysis (LR) in constructing models, and develop a Post-Thrombotic Syndrome (PTS) risk stratification tool. METHODS: We retrospectively collected and analyzed relevant case information of 618 patients diagnosed with DVT from January 2012 to December 2021 in three different tertiary hospitals in Jiangxi Province as the modeling group. Additionally, we used the case information of 212 patients diagnosed with DVT from January 2022 to January 2023 in two tertiary hospitals in Hubei Province and Guangdong Province as the validation group. We extracted electronic medical record information including general patient data, medical history, laboratory test indicators, and treatment data for analysis. We established DT and LR models and compared their predictive performance using receiver operating characteristic (ROC) curves and confusion matrices. Internal and external validations were conducted. Additionally, we utilized LR to generate nomogram charts, calibration curves, and decision curves analysis (DCA) to assess its predictive accuracy. RESULTS: Both DT and LR models indicate that Year, Residence, Cancer, Varicose Vein Operation History, DM, and Chronic VTE are risk factors for PTS occurrence. In internal validation, DT outperforms LR (0.962 vs 0.925, z = 3.379, P < 0.001). However, in external validation, there is no significant difference in the area under the ROC curve between the two models (0.963 vs 0.949, z = 0.412, P = 0.680). The validation results of calibration curves and DCA demonstrate that LR exhibits good predictive accuracy and clinical effectiveness. A web-based calculator software of nomogram (https://sunxiaoxuan.shinyapps.io/dynnomapp/) was utilized to visualize the logistic regression model. CONCLUSIONS: The combination of decision tree and logistic regression models, along with the web-based calculator software of nomogram, can assist healthcare professionals in accurately assessing the risk of PTS occurrence in individual patients with lower limb DVT.

The Utility of Advanced Lower-Extremity Duplex Using Pedal Acceleration Time in the Management of the Threatened Diabetic Foot.

BACKGROUND: Patients with diabetes and diffuse infrageniculate arterial disease who present with chronic limb-threatening ischemia require an exact anatomical plan for revascularization. Advanced pedal duplex can be used to define possible routes for revascularization. In addition, pedal acceleration time (PAT) can predict the success or failure of both medical and surgical interventions. METHODS: A retrospective review of patients who were referred to our group for unilateral limb-threatening ischemia with isolated infrageniculate disease was conducted. Pedal duplex and PAT at the base of the wound was performed before and 1 week after intervention. The primary endpoint was limb salvage at 1 year. Revascularization was defined as direct or indirect based on the angiosome concept. RESULTS: Fifty-four patients meeting inclusion criteria presented over a 5-year period (toe wound, n = 42; heel wound, n = 8; both, n = 4). At 1 year, 10 (18.5%) had required below-knee amputation, whereas the remainder had healed/improved. Limb salvage was predicted by absence of ongoing smoking, absence of dialysis, and postprocedural PAT (class I/II). Limb salvage did not correlate with direct versus indirect revascularization. CONCLUSIONS: Advanced lower-extremity duplex in conjunction with determining PAT at the area of concern is a useful technique for mapping the vasculature and identifying targets for revascularization in patients with diffuse infrageniculate disease. Target artery revascularization to the wound bed resulting in a PAT less than 180 msec is predictive of limb salvage, regardless of whether perfusion is direct or indirect.

[Impact of anemia on incidence of perioperative lower limb deep vein thrombosis in patients undergoing total hip arthroplasty].

Objective: To explore the impact of anemia on the incidence of perioperative lower limb deep vein thrombosis (DVT) in patients undergoing total hip arthroplasty (THA). Methods: A retrospective analysis was conducted on clinical data of 1 916 non-fracture patients who underwent THA between September 2015 and December 2021, meeting the selection criteria. Among them, there were 811 male and 1 105 female patients, aged between 18 and 94 years with an average of 59.2 years. Among the patients, 213 were diagnosed with anemia, while 1 703 were not. Preoperative DVT was observed in 55 patients, while 1 861 patients did not have DVT preoperatively (of which 75 patients developed new-onset DVT postoperatively). Univariate analysis was performed on variables including age, gender, body mass index (BMI), diabetes, hypertension, history of tumors, history of thrombosis, history of smoking, revision surgery, preoperative D-dimer positivity (≥0.5 mg/L), presence of anemia, operation time, intraoperative blood loss, transfusion requirement, and pre- and post-operative levels of red blood cells, hemoglobin, hematocrit, and platelets. Furthermore, logistic regression was utilized for multivariate analysis to identify risk factors associated with DVT formation. Results: Univariate analysis showed that age, gender, hypertension, revision surgery, preoperative levels of red blood cells, preoperative hemoglobin, preoperative D-dimer positivity, and anemia were influencing factors for preoperative DVT ( P<0.05). Further logistic regression analysis indicated that age (>60 years old), female, preoperative D-dimer positivity, and anemia were risk factors for preoperative DVT ( P<0.05). Univariate analysis also revealed that age, female, revision surgery, preoperative D-dimer positivity, anemia, transfusion requirement, postoperative level of red blood cells, and postoperative hemoglobin level were influencing factors for postoperative new-onset DVT ( P<0.05). Further logistic regression analysis indicated that age (>60 years old), female, and revision surgery were risk factors for postoperative new-onset DVT ( P<0.05). Conclusion: The incidence of anemia is higher among patients with preoperative DVT for THA, and anemia is an independent risk factor for preoperative DVT occurrence in THA. While anemia may not be an independent risk factor for THA postoperative new-onset DVT, the incidence of anemia is higher among patients with postoperative new-onset DVT.

Effects of additional exercise therapy after a successful vascular intervention for people with symptomatic peripheral arterial disease.

BACKGROUND: Peripheral arterial disease (PAD) is characterised by obstruction or narrowing of the large arteries of the lower limbs, usually caused by atheromatous plaques. Most people with PAD who experience intermittent leg pain (intermittent claudication) are typically treated with secondary prevention strategies, including medical management and exercise therapy. Lower limb revascularisation may be suitable for people with significant disability and those who do not show satisfactory improvement after conservative treatment. Some studies have suggested that lower limb revascularisation for PAD may not confer significantly more benefits than supervised exercise alone for improved physical function and quality of life. It is proposed that supervised exercise therapy as adjunctive treatment after successful lower limb revascularisation may confer additional benefits, surpassing the effects conferred by either treatment alone. OBJECTIVES: To assess the effects of a supervised exercise programme versus standard care following successful lower limb revascularisation in people with PAD. SEARCH METHODS: We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, two other databases, and two trial registers, most recently on 14 March 2023. SELECTION CRITERIA: We included randomised controlled trials which compared supervised exercise training following lower limb revascularisation with standard care following lower limb revascularisation in adults (18 years and older) with PAD. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were maximum walking distance or time (MWD/T) on the treadmill, six-minute walk test (6MWT) total distance, and pain-free walking distance or time (PFWD/T) on the treadmill. Our secondary outcomes were changes in the ankle-branchial index, all-cause mortality, changes in health-related quality-of-life scores, reintervention rates, and changes in subjective measures of physical function. We analysed continuous data by determining the mean difference (MD) and 95% confidence interval (CI), and dichotomous data by determining the odds ratio (OR) with corresponding 95% CI. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We identified seven studies involving 376 participants. All studies involved participants who received either additional supervised exercise or standard care after lower limb revascularisation. The studies' exercise programmes varied, and included supervised treadmill walking, combined exercise, and circuit training. The duration of exercise therapy ranged from six weeks to six months; follow-up time ranged from six weeks to five years. Standard care also varied between studies, including no treatment or advice to stop smoking, lifestyle modifications, or best medical treatment. We classified all studies as having some risk of bias concerns. The certainty of the evidence was very low due to the risk of bias, inconsistency, and imprecision. The meta-analysis included only a subset of studies due to concerns regarding data reporting, heterogeneity, and bias in most published research. The evidence was of very low certainty for all the review outcomes. Meta-analysis comparing changes in maximum walking distance from baseline to end of follow-up showed no improvement (MD 159.47 m, 95% CI -36.43 to 355.38; I2 = 0 %; 2 studies, 89 participants). In contrast, exercise may improve the absolute maximum walking distance at the end of follow-up compared to standard care (MD 301.89 m, 95% CI 138.13 to 465.65; I2 = 0 %; 2 studies, 108 participants). Moreover, we are very uncertain if there are differences in the changes in the six-minute walk test total distance from baseline to treatment end between exercise and standard care (MD 32.6 m, 95% CI -17.7 to 82.3; 1 study, 49 participants), and in the absolute values at the end of follow-up (MD 55.6 m, 95% CI -2.6 to 113.8; 1 study, 49 participants). Regarding pain-free walking distance, we are also very uncertain if there are differences in the mean changes in PFWD from baseline to treatment end between exercise and standard care (MD 167.41 m, 95% CI -11 to 345.83; I2 = 0%; 2 studies, 87 participants). We are very uncertain if there are differences in the absolute values of ankle-brachial index at the end of follow-up between the intervention and standard care (MD 0.01, 95% CI -0.11 to 0.12; I2 = 62%; 2 studies, 110 participants), in mortality rates at the end of follow-up (OR 0.92, 95% CI 0.42 to 2.00; I2 = 0%; 6 studies, 346 participants), health-related quality of life at the end of follow-up for the physical (MD 0.73, 95% CI -5.87 to 7.33; I2 = 64%; 2 studies, 105 participants) and mental component (MD 1.04, 95% CI -6.88 to 8.95; I2 = 70%; 2 studies, 105 participants) of the 36-item Short Form Health Survey. Finally, there may be little to no difference in reintervention rates at the end of follow-up between the intervention and standard care (OR 0.91, 95% CI 0.23 to 3.65; I2 = 65%; 5 studies, 252 participants). AUTHORS' CONCLUSIONS: There is very uncertain evidence that additional exercise therapy after successful lower limb revascularisation may improve absolute maximal walking distance at the end of follow-up compared to standard care. Evidence is also very uncertain about the effects of exercise on pain-free walking distance, six-minute walk test distance, quality of life, ankle-brachial index, mortality, and reintervention rates. Although it is not possible to confirm the effectiveness of supervised exercise compared to standard care for all outcomes, studies did not report any harm to participants from this intervention after lower limb revascularisation. Overall, the evidence incorporated into this review was very uncertain, and additional evidence is needed from large, well-designed, randomised controlled studies to more conclusively demonstrate the role additional exercise therapy has after lower limb revascularisation in people with PAD.

Lower extremity arterial disease vs. coronary artery disease: mortality differences after revascularization.

BACKGROUND AND AIMS: Patients undergoing revascularization for lower extremity arterial disease (LEAD) may face a higher risk of mortality than those with coronary artery disease (CAD). This study aimed to characterize the difference in mortality risk between patients undergoing revascularization for LEAD and CAD and identify associated factors. METHODS: The 1-year database of 10 754 patients undergoing revascularization for CAD (n = 6349) and LEAD (n = 4405) was analysed. Poisson regression models were used to characterize interpopulation differences in mortality, adjusting for baseline clinical features, including age, sex, polyvascular disease, comorbidities, medications, and vulnerabilities. RESULTS: Individuals with LEAD were older, were more likely to have polyvascular disease, had more comorbidities, and received fewer cardioprotective drugs than those with CAD. Vulnerabilities remained more common in the LEAD group even after adjusting for these clinical features. The crude risk ratio of mortality incidence for LEAD vs. CAD was 2.91 (95% confidence interval, 2.54-3.34), attenuated to 2.14 (1.83-2.50) after controlling for age, sex, and polyvascular disease. The percentage attenuation in the excessive mortality associated with LEAD was 29%. The stepwise addition of comorbidities, medications, and vulnerabilities as adjusting factors attenuated the incidence risk ratio to 1.48 (1.26-1.72), 1.33 (1.12-1.58), and 1.17 (0.98-1.39), respectively, and increased the percentage attenuation to 64%, 73%, and 86%, respectively. CONCLUSIONS: Mortality risk was almost three-fold higher in patients undergoing revascularization for LEAD than in those with CAD. The excessive mortality was considerably attributable to inter-group differences in baseline characteristics, including potentially clinically or socially modifiable factors.

Predictive value of prenatal ultrasound combined with long non-coding RNA CRNDE of women for their postpartum lower extremity deep venous thrombosis.

OBJECTIVE: Deep vein thrombosis (DVT) is a common complication in obstetrics that needs early interaction. The study examined the expression change and clinical value of long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) in DVT early diagnosis. METHODS: One hundred patients with DVT after delivery and 100 healthy parturients without DVT were enrolled. Serum samples were collected one day before delivery and received qRT-PCR for mRNA detection. Prenatal coagulation markers including prothrombin time (PT), activated partial prothrombin time (APTT), fibrinogen (FIB) and thrombin time (TT), D-dimer (D-D), thrombomodulin (TM), and peroxidase anti-peroxidase soluble complex (PAP) were tested. The receiver operating characteristic (ROC) curve was drawn for the diagnostic value assessment. RESULTS: LncRNA CRNDE levels increased remarkably in the serum of DVT patients compared with the healthy controls, which were negatively correlated with serum concentration of PT, APTT, and TT while positively correlated with FIB, D-D, TM, and PAP. Serum CRNDE (HR = 5.973, 95% CI = 2.990-11.933, p < .001) was independently related to the occurrence of DVT after delivery. Then, ROC curve using serum CRNDE showed a good diagnostic value for DVT with the AUC of 0.899. ROC curve of ultrasonography combined with CRNDE produced an AUC of 0.968, and both sensitivity and specificity were enhanced compared to a single indicator. CONCLUSIONS: The increase of CRNDE level was an independent risk factor for postpartum DVT. Prenatal ultrasonography combined with CRNDE can improve the predictive efficacy for DVT.

Exercise Therapy for Peripheral Artery Disease.

PURPOSE OF REVIEW: To summarize evidence regarding exercise treatments for lower extremity peripheral artery disease (PAD). RECENT FINDINGS: Supervised walking exercise is recommended by practice guidelines for PAD. Supervised treadmill exercise improves treadmill walking distance by approximately 180 m and 6-min walk distance by 30-35 m, compared to control. The Centers for Medicaid and Medicare Services covers 12 weeks of supervised exercise, but most people with PAD do not participate. Home-based walking exercise may be more convenient and accessible than supervised exercise. In randomized clinical trials, home-based walking exercise interventions incorporating behavioral methods, such as accountability to a coach, goal-setting, and self-monitoring, improved 6-min walk distance by 40-54 m, compared to control. Arm and leg ergometry also improved walking endurance for people with PAD, but efficacy compared to walking exercise remains unclear. Walking exercise is first-line therapy for PAD-related walking impairment and can be effective in either a supervised or a structured home-based setting.

Effect of veno-arterial extracorporeal membrane oxygenation lower-extremity cannulation on intra-arterial flow characteristics, oxygen content, and thrombosis risk.

PURPOSE: This study aimed to investigate the effects of lower-extremity cannulation on the intra-arterial hemodynamic environment, oxygen content, blood damage, and thrombosis risk under different levels of veno-arterial (V-A) ECMO support. METHODS: Computational fluid dynamics methods were used to investigate the effects of different levels of ECMO support (ECMO flow ratios supplying oxygen-rich blood 100-40 %). Flow rates and oxygen content in each arterial branch were used to determine organ perfusion. A new thrombosis model considering platelet activation and deposition was proposed to determine the platelet activation and thrombosis risk at different levels of ECMO support. A red blood cell damage model was used to explore the risk of hemolysis. RESULTS: Our study found that partial recovery of cardiac function improved the intra-arterial hemodynamic environment, with reduced impingement of the intra-arterial flow field by high-velocity blood flow from the cannula, a flow rate per unit time into each arterial branch closer to physiological levels, and improved perfusion in the lower extremities. Partial recovery of cardiac function helps reduce intra-arterial high shear stress and residence time, thereby reducing blood damage. The overall level of hemolysis and platelet activation in the aorta decreased with the gradual recovery of cardiac contraction function. The areas at high risk of thrombosis under V-A ECMO femoral cannulation support were the aortic root and the area distal to the cannula, which moved to the descending aorta when cardiac function recovered to 40-60 %. However, with the recovery of cardiac contraction function, hypoxic blood pumped by the heart is insufficient in supplying oxygen to the front of the aortic arch, which may result in upper extremity hypoxia. CONCLUSION: We developed a thrombosis risk prediction model applicable to ECMO cannulation and validated the model accuracy using clinical data. Partial recovery of cardiac function contributed to an improvement in the aortic hemodynamic environment and a reduction in the risk of blood damage; however, there is a potential risk of insufficient perfusion of oxygen-rich blood to organs.

Modelling lower-limb peripheral arterial disease using clinically available datasets: impact of inflow boundary conditions on hemodynamic indices for restenosis prediction.

BACKGROUND AND OBJECTIVES: The integration of hemodynamic markers as risk factors in restenosis prediction models for lower-limb peripheral arteries is hindered by fragmented clinical datasets. Computed tomography (CT) scans enable vessel geometry reconstruction and can be obtained at different times than the Doppler ultrasound (DUS) images, which provide information on blood flow velocity. Computational fluid dynamics (CFD) simulations allow the computation of near-wall hemodynamic indices, whose accuracy depends on the prescribed inlet boundary condition (BC), derived from the DUS images. This study aims to: (i) investigate the impact of different DUS-derived velocity waveforms on CFD results; (ii) test whether the same vessel areas, subjected to altered hemodynamics, can be detected independently of the applied inlet BC; (iii) suggest suitable DUS images to obtain reliable CFD results. METHODS: CFD simulations were conducted on three patients treated with bypass surgery, using patient-specific DUS-derived inlet BCs recorded at either the same or different time points than the CT scan. The impact of the chosen inflow condition on bypass hemodynamics was assessed in terms of wall shear stress (WSS)-derived quantities. Patient-specific critical thresholds for the hemodynamic indices were applied to identify critical luminal areas and compare the results with a reference obtained with a DUS image acquired in close temporal proximity to the CT scan. RESULTS: The main findings indicate that: (i) DUS-derived inlet velocity waveforms acquired at different time points than the CT scan led to statistically significantly different CFD results (p<0.001); (ii) the same luminal surface areas, exposed to low time-averaged WSS, could be identified independently of the applied inlet BCs; (iii) similar outcomes were observed for the other hemodynamic indices if the prescribed inlet velocity waveform had the same shape and comparable systolic acceleration time to the one recorded in close temporal proximity to the CT scan. CONCLUSIONS: Despite a lack of standardised data collection for diseased lower-limb peripheral arteries, an accurate estimation of luminal areas subjected to altered near-wall hemodynamics is possible independently of the applied inlet BC. This holds if the applied inlet waveform shares some characteristics - derivable from the DUS report - as one matching the acquisition time of the CT scan.

Exploring Risk Factors for Lower Extremity Deep Vein Thrombosis Patients with Co-existing Pulmonary Embolism Based on Multiple Logistic Regression Model.

Valuable data on deep vein thrombosis (DVT) patients with coexisting pulmonary embolism (PE) is scarce. This study aimed to identify risk factors associated with these patients and develop logistic regression models to select high-risk DVT patients with coexisting PE. We retrospectively collected data on 150 DVT patients between July 15, 2022, and June 15, 2023, dividing them into groups based on the presence of coexisting PE. Univariate and multivariate logistic regression analyses were performed to identify significant risk factors and construct predictive models. Discrimination and calibration statistics evaluated the validation and accuracy of the developed models. Of the 130 patients analyzed, 40 (30.77%) had coexisting PE. Univariate analysis revealed four significant predictors of DVT patients with coexisting PE: sex (OR 3.83, 95% CI: [1.76; 8.59], P = 0.001), body mass index (BMI) (OR 1.50, 95% CI: [1.28; 1.75], P < 0.001), chronic disease (OR 5.15, 95% CI: [2.32; 11.8], P < 0.001), and high-density lipoprotein (HDL) (OR 0.03, 95% CI: [0.01; 0.20], P < 0.001). Additionally, BMI > 24 kg/m2 (OR 9.70, 95% CI: [2.70; 67.5], P < 0.001) and BMI > 28 kg/m2 (OR 4.80, 95% CI: [2.15; 11.0], P < 0.001) were associated with concurrent PE. Three multiple regression models were constructed, with areas under the receiver-operating characteristic curves of 0.925 (95% CI: [0.882; 0.968]), 0.908 (95% CI: [0.859; 0.957]), and 0.890 (95% CI: [0.836; 0.944]), respectively. Sex, BMI, chronic disease, and HDL levels are significant predictors of DVT patients with coexisting PE.

Cross-leg flaps: A nonmicrosurgical alternative treatment method in complex lower extremity trauma reconstruction.

OBJECTIVES: This study aimed to present our experiences with cross-leg flap surgery, which demonstrates successful outcomes in lower limb soft tissue defects without the necessity of microsurgical intervention. PATIENTS AND METHODS: The retrospective study included 26 patients (18 males, 8 females; mean age: 35.6±12.2 years; range, 18 to 65 years) between January 2015 and September 2019. A fasciocutaneous cross-leg flap was applied to the recipient extremity, and the extremities were immobilized by a tubular external fixator. Flap divisions were performed on the 21st postoperative day. At least two years of clinical outcomes were presented. RESULTS: Twenty-five flaps survived and recovered completely without any complication at the donor site, flaps, or the recipient area. In one diabetic patient, partial flap loss was encountered, which granulated with secondary healing. All patients demonstrated stable wound coverage, with none demanding additional soft tissue surgeries. All patients resumed normal ambulation and physical activity without any residual joint stiffness. CONCLUSION: Cross-leg flap method is an effective and respectable option for extremity salvage as a good alternative to free flaps for the management of traumatic complex lower limb defects. This method is simple, provides abundant blood supply to the wound, and does not require microsurgical experience or a good working recipient artery.