Abstract P223: Vitamin D Supplementation Improves Measures Of Arterial Stiffness And Vascular Function In Adolescents Suffering From Orthostatic Intolerance

Background: In previous work we identified a group of adolescents with orthostatic intolerance (OI) presenting as postural orthostatic tachycardia syndrome or syncope with impairment in autonomic and vascular response upon head up tilt. Low vitamin D level correlated with the severity of symptoms. In this pilot study we hypothesized that vitamin D supplementation will improve the vascular function in these adolescents. Methods: A cohort of twenty Adolescents (mean age= 16.2 years, 4 males) who are vitamin D deficient had a non-invasive measurements of brachial BP, aortic BP, augmentation index at heart rate of 75 beats per minute (AIx75), and carotid-femoral pulse wave velocity (cf-PWV) using the SphygmoCor XCEL System at baseline and after two months of vitamin D supplementation (2000-5000 IU daily based on baseline level). Both right and left side ankle pressure and ankle brachial index (ABI) were assessed using COLIN VP-1000 vascular profiling system. Impedance Cardiography (ICG) was used to estimate total arterial compliance (TAC) and thoracic fluid content (TFC) in supine position at rest and after hand grip challenge. Results: As shown in the table. Compared to baseline, vitamin D supplementation increased vitamin D level, increased TAC and TFC at baseline and under stress challenge. It also tended to reduced AIx75 and cf-PWV and reduced both right and left ankle pressure and ABI Conclusions: Vitamin D supplementation improved different measures of vascular function in adolescent. These data provides evidence of potential therapeutic benefit of vitamin D supplementation for patients suffering from orthostatic intolerance who are vitamin D deficient.

Association between modified ankle-brachial pressure index and indices of adiposity

Objectives: Obesity is one of the important risk factors for peripheral arterial disease (PAD). Ankle-brachial pressure index (ABPI) is a non-invasive test, which may be used for earlier detection of PAD. ABPI in healthy obese/overweight subjects has not been studied. In present study, we investigated correlation of adiposity indices with ABPI. We have also compared ABPI by three different methods in healthy obese/overweight subjects. Materials and Methods: Weight, height, body mass index (BMI), waist circumference, hip circumference (HC), waist height ratio, waist hip ratio, skin fold thickness, and body fat percentage were measured in 45 healthy overweight/obese males. Ankle and brachial pressures were measured by Doppler ultrasound based method. ABPI was calculated using high ankle pressure (ABPI-HIGH), mean ankle pressure (ABPI-MEAN), and low ankle pressure (ABPI-LOW) methods. Results: BMI and HC show positive significant correlation with ABPI-LOW (P = 0.028, P = 0.046, respectively). Significant difference was observed between ABPI-LOW and ABPI-HIGH (P = 0.003). ABPI-MEAN and ABPILOW were also significantly different (P < 0.001). Conclusion: There is a correlation of obesity indices with ABPI-LOW. ABPI-LOW methods could be more appropriate method and contrastingly HC may have direct correlation with PAD detection by ABPI in apparently healthy obese.

Efficiency of mesenchymal stromal cells (MSCs) in the treatment of patients with critical limb-threatening ischemia

Relevance. The relevance of the study is determined by the fact that hopes are placed in the cell therapy for patients with critical limb-threatening (CLI) ischemia as a method of the restoration of blood circulation in the affected limb in patients who cannot undergo surgical or endovascular intervention. Aim. To evaluate the efficiency of allogeneic MSCs for the treatment of critical lower limb ischemia (randomized placebo-controlled study).Materials and methods. The study included 34 patients with critical lower limb ischemia (grade 4 according to Pokrovsky). There were 18 patients in the MSC group, and 16 patients in the placebo group). The groups were comparable concerning age, disease duration, and comorbidities. Allogeneic MSCs (phenotype CD73+, CD90+, CD105+, CD45–, CD34–, CD14–) were injected into the posterior calf muscles. Clinical outcome, ankle pressure, transcutaneous oxygen tension (tcpO2), and pain-free walking distance (PFWD) were evaluated. The patients were followed-up for 12–36 months. According to the clinical outcome in each group, the patients were divided into subgroups with «effect (+)» or «effect (–)». In 2 patients, there was an «uncertain clinical outcome». When analyzing the results, these patients were assigned to one or another subgroup.Results. In the MSC and placebo groups, the clinical outcome assessed as «effect (+)» or «effect (–)» did not differ (OR 1.5; 95 % CI 0.34–6.7). With different variants of group formation and with the assignment of patients with an «uncertain clinical outcome» to a one or another subgroup, the final results neither differed. According to instrumental research methods (PFWD, tcpO2, ankle pressure, angiography), there were no differences in the MSC and placebo groups. Conclusion. With different variants of analysis and group formation, no convincing evidence that allogeneic MSCs can be effective for the treatment of critical lower limb ischemia have been obtained.

Comparison of Ankle Pressure, Systolic Toe Pressure, and Transcutaneous Oxygen Pressure to Predict Major Amputation After 1 Year in the COPART Cohort

The hemodynamic definition of critical limb ischemia (CLI) has evolved over time but remains controversial. We compared the prediction of major amputation by 3 hemodynamic methods. Patients were selected from the Cohorte des Patients ARTériopathes cohort of patients hospitalized for peripheral arterial disease. Patients with CLI were enrolled according to the Trans-Atlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease II definition and followed up for at least 1 year. We compared the major amputation rate according to initial ankle pressure (AP), systolic toe pressure (STP), and forefoot transcutaneous oxygen pressure (TcPO2); 556 patients were included and divided into surgical (264) and medical (292) groups. The AP failed to identify 42% of patients with CLI. After 1 year, 27% of medical and 17% of surgical patients had undergone major amputation. The TP <30 mm Hg predicted major amputation in the whole sample and in the medical group (odds ratio [OR] 3.5 [1.7-7.1] and OR 5 [2-12.4], respectively), but AP did not. The TcPO2 <10 mm Hg also predicted major amputation (OR 2.3 [1.5-3.5] and OR 3.8 [2.1-6.8]). The best predictive thresholds to predict major amputation were STP <30 mm Hg and TcPO2 <10 mm Hg. None of these methods performed before surgery was able to predict outcome in the revascularized patients.

Distal Fibula Osteotomies Improve Tibiotalar Joint Compression

Category: Basic Sciences/Biologics Introduction/Purpose: Compression is a vital component of achieving a successful ankle arthrodesis. Various modifications of the fibula are used in hopes of achieving higher clinical rates of successful fusion in ankle arthrodesis procedures. We hypothesized that distal fibula osteotomies would improve tibiotalar joint compression under various loading conditions. The purpose of this study was to evaluate the effect of various distal fibula osteotomies on tibiotalar joint compression. Methods: Eight paired adult cadaveric lower extremity specimens with an intact ankle joint and syndesmosis were prepared by exposing and fixating together the proximal tibia and fibula. A jig was constructed to secure the specimen in a vertical position while allowing free axial loading. An anterior surgical approach to the ankle was performed and the joint cartilage denuded. A pressure transducer was used to record baseline ankle pressure distribution. The proximal specimen was loaded with 30, 50, and 100 N static weight and ankle pressure measurements repeated for each load. The fibula was surgically modified with the three procedures: (1) oblique fibular osteotomy 3 cm proximal to the ankle joint; (2) 1 cm long distal fibula resection; (3) complete distal fibula excision. Increasing loads of 30, 50, and 100 N following each surgical procedure were applied and the ankle pressure measurements repeated. Results: Distal fibula resection increased tibiotalar joint force, peak pressure, and contact area compared to intact fibula control for 30, 50, and 100 N loads applied (p<0.05). Compared to intact fibula control, an oblique osteotomy performed and 30 N applied force resulted in a mean ankle joint force increase of 7.5 N (p = 0.007). A 1 cm excisional fibula osteotomy under a 30 N load significantly increased the ankle joint force by 6.6 N (p = 0.015). Complete distal fibula resection under 30 N load significantly increased the ankle joint force compared to control by 13.9 N (p < 0.001). Similar trends were seen for 50 N and 100 N loads with significance reached (*) as represented in Figure 1 (error bar = standard error). Conclusion: A distal fibula oblique osteotomy, 1 cm excisional osteotomy, or complete distal fibula excision may increase the amount of force transmitted to the ankle joint under loading. Our findings suggest complete distal fibular resection results in the highest ankle joint force, contact area, and peak pressure of the surgical options tested. Leaving the fibula intact may decrease tibiotalar compression during ankle arthrodesis. Clinical testing would be important to ultimately test the effects on rates of successful fusion.