Limb outcomes based on limb severity and anatomic complexity following infrapopliteal vein bypass for Japanese patients with chronic limb-threatening ischemia.

OBJECTIVE: The 2019 Global Vascular Guidelines recommend a suitable initial revascularization method with reference to limb severity (wound, ischemia, and foot infection [WIfI] stage) and anatomic complexity (Global Limb Anatomical Staging System [GLASS] stage). However, limb outcomes after revascularization among WIfI and GLASS stages have not been investigated fully after infrapopliteal vein bypass. The purpose of this study was to assess the four Global Vascular Guideline-recommended limb outcomes after infrapopliteal vein bypass in cases with different WIfI and GLASS stages. METHODS: Patients who underwent infrapopliteal vein bypass for chronic limb-threatening ischemia at a single center were analyzed retrospectively. Medium-term limb outcomes were compared among WIfI and GLASS stages. The primary end points were limb salvage rate and major to minor amputation ratio, and the secondary end points were wound healing rate and wound healing time. RESULTS: A total of 353 infrapopliteal vein bypasses were performed in 284 patients with tissue loss (male, 193 patients; median age, 77 years; diabetes, 71%; hemodialysis, 41%). A total of 111 limbs (31%) required only minor amputation and 38 limbs (11%) required major amputation. The major to minor amputation ratio was 0.34 with no significant differences among WIfI stages or GLASS stages. The 3-year limb salvage rate was 87%. This rate was significantly lower in WIfI stage 4 than in stage 2 (P = .049), but did not differ significantly among GLASS stages. The 12-month wound healing rate was 86%. This rate was also significantly lower in WIfI stage 4 than in stages 2 and 3 (both P < .001), but did not differ significantly among GLASS stages. The median wound healing time was 55 days (range, 32-110 days), and was significantly longer in WIfI stage 4 compared with stages 2 (P = .001) and 3 (P < .001), but showed no significant differences among GLASS stages. CONCLUSIONS: The limb salvage rate, wound healing rate, and wound healing time were associated with limb severity (WIfI stage), but not with anatomic complexity (GLASS stage). These findings suggest that an appropriate preoperative strategy and careful perioperative management are important for patients with greater limb severity.

The Modified Frailty Index Does Not Predict Mortality After Major Lower Extremity Amputation for Peripheral Arterial Disease in an Asian Population.

BACKGROUND: Patients with critical limb ischemia (CLI) who undergo major lower extremity amputation (LEA) have been associated with high one-year mortality rates. Previous western-based studies have identified risk factors that exponentiate these poor outcomes, including nonambulatory status and cardiovascular morbidity. We assessed the effect of frailty, using the modified frailty index (mFI) in a cohort undergoing major LEA for CLI to predict mortality, perioperative complications, and unplanned readmissions in a tertiary institution from Singapore. METHODS: Data on patients who had undergone major LEA from January 2016 to December 2017 were collected retrospectively. Inclusion criteria were below-knee amputations (BKAs) or above-knee amputations (AKAs) performed for peripheral arterial disease-related tissue loss or sepsis only. Patients were categorized into 3 risk groups based on the 11-variable mFI: low mFI, 0-0.27; moderate mFI, 0.36-0.54; and high mFI ≥0.63. Univariate and multivariate analysis was performed using logistic regression analysis. RESULTS: 211 patients underwent major LEA, of whom 133 (63.0%) had undergone BKA. The mean mFI was 0.41 (range 0-0.81). 84/211 (39.8%) died within 1 year after the procedure, with mortality rates of 25/65 (38.4%), 49/127 (38.6%), and 10/19 (52.6%) in the low-, moderate-, high-mFI categories, respectively. High and moderate mFI had failed to demonstrate an increased risk of mortality when compared with the low-mFI group (P > 0.05). 91/211 (43.1%) patients had perioperative complications, whereas 27/211 (12.8%) patients were readmitted within 30 days of discharge. Myocardial infarction, chronic kidney disease, and atrial fibrillation were found to be predictive of poor outcomes after major LEA. CONCLUSIONS: Frailty as measured with the mFI did not predict outcome after major LEA. This could be due to confounding effects such as high prevalence of renal dysfunction and the constancy of diabetes and peripheral vascular disease in this population that would reduce the differentiation of patients using the mFI.

Early and Midterm Experience With the Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Asian Patients With Chronic Limb-Threatening Ischemia: One-Year Clinical and Imaging Outcomes From the DISAPEAR Registry.

Purpose: To report an experience with the Absorb bioresorbable vascular scaffold (BVS) in an Asian cohort with chronic limb-threatening ischemia (CLTI) from the DISAPEAR (Drug Impregnated Bioresorbable Stent in Asian Population Extremity Arterial Revascularization) registry. Materials and Methods: A retrospective analysis was conducted of 41 patients (median age 64 years; 23 men) with CLTI owing to >50% de novo infrapopliteal lesions (n=53) treated with the Absorb BVS between August 2012 and June 2017. The majority of patients (37, 90%) had diabetes, 24 (59%) had ischemic heart disease, and 39 (95%) had Rutherford category 5/6 ischemia with tissue loss. The mean lesion length was 22.7±17.2 mm; 10 (24%) lesions were severely calcified. Assessments included technical success, primary patency, freedom from clinically-driven target lesion revascularization (CD-TLR), amputation-free survival, limb salvage, complete wound healing, resolution of rest pain, and resolution of CLTI without TLR at 6 and 12 months after the index intervention. Results: Overall, 69 scaffolds were implanted in the 53 lesions, with 100% technical success. There were no deaths within 30 days of the index procedure. The primary patency rates at 6 and 12 months were 95% and 86%, respectively. The corresponding rates of freedom from CD-TLR were 98% and 93%, respectively. Freedom from major amputation was 98% at both time points, and amputation-free survival was 93% and 85% at 6 and 12 months after the index procedure. Wound healing occurred in 31 patients (79%) with Rutherford category 5/6 ischemia by the end of 12 months. Conclusion: The Absorb BVS demonstrated good 1-year patency and clinical outcomes in CLTI patients with complex infrapopliteal disease.

Racial Differences in Ischaemia/Bleeding Risk Trade-Off during Anti-Platelet Therapy: Individual Patient Level Landmark Meta-Analysis from Seven RCTs.

BACKGROUND: Prolonged dual anti-platelet therapy (DAPT) is intended to reduce ischaemic events, at the cost of an increased bleeding risk in patients undergoing percutaneous coronary intervention (PCI). In this study, we evaluated whether race influences the ischaemia/bleeding risk trade-off. METHODS: We searched for randomized clinical trials (RCTs) comparing DAPT duration after PCI. To compare the benefit or harm between DAPT duration by race, individual patient-level landmark meta-analysis was performed after discontinuation of the shorter duration DAPT group in each RCT. The primary ischaemic endpoint was major adverse cardiac events (MACEs), and the primary bleeding endpoint was major bleeding events (clinicaltrials.gov NCT03338335). RESULTS: Seven RCTs including 16,518 patients (8,605 East Asians, 7,913 non-East Asians) were pooled. MACE occurred more frequently in non-East Asians (0.8% vs. 1.8%, p < 0.001), while major bleeding events occurred more frequently in East Asians (0.6% vs. 0.3%, p = 0.001). In Cox proportional hazards model, prolonged DAPT significantly increased the risk of major bleeding in East Asians (hazard ratio [HR], 2.843, 95% confidence interval [CI], 1.474-5.152, p = 0.002), but not in non-East Asians (HR, 1.375, 95% CI, 0.523-3.616, p = 0.523). East Asians had a higher median probability risk ratio of bleeding to ischaemia (0.66 vs. 0.15), and the proportion of patients with higher probability of bleeding than ischaemia was significantly higher in East Asians (32.3% vs. 0.4%, p < 0.001). CONCLUSION: We suggest that the ischaemia/bleeding trade-off may be different between East Asians and non-East Asians. In East Asians, prolonged DAPT may have no effect in reducing the ischaemic risk, while significantly increases the bleeding risk.

Catheter-Directed Thrombolysis for Acute Limb Ischemia in an Asian Population.

BACKGROUND: The incidence of peripheral arterial occlusions in Asian populations is likely to increase exponentially in the present and future decades due to the adapted Western lifestyle in metropolitan Asian life, extended life expectancies, and high rates of smoking. The literature on thrombolytic treatment of peripheral arterial occlusions in Asian populations is limited. Therefore, we evaluated the thrombolysis results in a real-world contemporary Asian cohort of patients with peripheral arterial occlusions. METHODS: Retrospective review of all electronic patient records of patients who underwent thrombolytic therapy for peripheral arterial occlusions between July 2011 and July 2016 was conducted. Outcomes were angiographic patency, clinical success, bleeding complications, amputation rates, and mortality rates. RESULTS: In total, 82 patients (median age 66 years, range 34-95) underwent catheter-directed thrombolysis. Median treatment duration was 26 hr (3-209). Angiographic patency and clinical success rates were 64% and 66%, respectively. Bleeding complications occurred in 12% of patients of which 6% were major. Amputation-free rates were 81%, 67%, and 63% for 30 days, 6 months, and 1 year, respectively. In-hospital mortality was 6%. CONCLUSIONS: This study demonstrates that thrombolytic treatment of peripheral arterial occlusions in an Asian patient cohort yields comparable treatment success rates to Western cohorts; however, higher rates of bleeding complications are hazardous and remain a detrimental drawback of this treatment.

Ethnic minorities with critical limb ischemia derive equal amputation risk reduction from autologous cell therapy compared with whites.

OBJECTIVE: Ethnic minorities (nonwhites) with critical limb ischemia (CLI) have historically performed worse compared with whites with regard to major amputation risk reduction and amputation-free survival (AFS) after peripheral vascular intervention. This post hoc analysis was completed to determine whether this precedent also extended to treatment of CLI without a suitable revascularization option with intramuscular injections of concentrated bone marrow aspirate (cBMA). METHODS: The treatment arm of the randomized, double-blind, multicenter MarrowStim PAD Kit for the Treatment of Critical Limb Ischemia in Subjects with Severe Peripheral Arterial Disease (MOBILE) trial was stratified by ethnicity and evaluated for demographics, comorbidities, and outcomes. The primary and therapeutic end point was 1-year AFS and major amputation, respectively. Noninferiority analysis was performed with the margin set at historically reported hazard ratios. RESULTS: Thirty-seven minority (African American, Hispanic, other) CLI patients (9 placebo, 28 cBMA) with no suitable revascularization option were randomized to cBMA or placebo at a 3:1 ratio during the MOBILE trial. At 1-year follow-up for the treatment group, overall AFS was 80%. Of the 28 minority patients randomized to cBMA intervention, an 89% AFS rate was observed compared with 77% in whites. Specifically, 22 of 24 (92%) African Americans survived amputation free at 1-year follow-up. Noninferiority testing confirmed no difference between whites and the ethnic minority treated with cBMA with respect to major amputation reduction; however, noninferiority could not be confirmed with regard to AFS. No significant differences favoring whites treated with cBMA were noted in the secondary end points of vascular quality of life, limb pain, ankle-brachial index, toe-brachial index, transcutaneous oximetry, and 6-minute walk testing. CONCLUSIONS: This post hoc analysis of the MOBILE trial demonstrates noninferiority of cBMA intervention in minorities with no-option CLI for the therapeutic end point of major amputation prevention. cBMA represents a novel treatment paradigm and should be explored for minorities with poor revascularization options who face impending amputation secondary to progressive CLI.

Arteriographic Patterns of Atherosclerosis and the Association between Diabetes Mellitus and Ethnicity in Chronic Critical Limb Ischemia.

BACKGROUND: Disparate outcomes in critical limb ischemia (CLI) persist between ethnicities. The contribution of modifiable factors versus intrinsic biologic differences remains unclear. Hence, we aimed to quantify the associations between ethnicity and anatomic patterns of arterial occlusive disease in CLI, adjusting for known atherosclerotic risk factors. METHODS: We performed a retrospective, single-center review of consecutive patients presenting to the vascular surgery service with CLI. Arterial lesions were defined by location (aortoiliac = aorta and iliac arteries; femoral = common, profunda, and superficial femoral arteries; and popliteal-tibial = infrapopliteal and tibial arteries). Stenoses ≥50% were deemed hemodynamically significant. Associations between the patients' baseline arteriographic patterns, demographics, and medical comorbidities were defined using Kruskal-Wallis, χ2, and Mantel-Haenszel χ2 tests. RESULTS: Between August 2010 and January 2014, 286 CLI patients (n = 172 male, n = 176 tissue loss) were evaluated by the Vascular Surgery service. Two hundred seventy subjects had baseline arteriograms for analysis (black n = 134, 50%; Hispanic n = 78, 29%; Caucasian n = 58, 21%.) All ethnicities presented most frequently with simultaneous disease in all infrainguinal segments (n = 124, 46%). Of Hispanics, 30% (n = 23) presented with isolated infrapopliteal disease, which was higher than any other ethnic group (P = 0.02, χ2). Caucasians (n = 8, 14%) presented more frequently with isolated aortoiliac occlusive disease than either Hispanics (n = 0, 0%) or blacks (n = 2, 1%; P = 0.06). Diabetes mellitus was most prevalent among Hispanics (n = 72, 85%) relative to blacks (n = 77, 55%) and Caucasians (n = 32, 52%; P < 0.001, χ2). Median hemoglobin A1c (HbA1c) was also highest among Hispanics (7.3%, interquartile range [IQR] 6.2-9.9) versus blacks and Caucasians (6.6%, IQR 5.8-8.2 and 6.0%, IQR 5.6-7.6; P = 0.002, Kruskal-Wallis). Tobacco abuse was most frequent among Caucasians (n = 53, 87%) and blacks (n = 113, 81%). Forty-eight (57%) of Hispanics abused tobacco (P = 0.001, χ2.) Subgroup analysis of subjects stratified by baseline HbA1c revealed that there was no relationship between ethnicity and isolated infrapopliteal disease among subjects with HbA1c ≤8.8% (P = 0.58, Mantel-Haenszel χ2). Conversely, patients with poorer glycemic control (HbA1c ≥ 8.9%) were more frequently Hispanic and had a higher probability of having isolated infrapopliteal disease (P = 0.005, Mantel-Haenszel χ2). CONCLUSIONS: Hispanic patients present more frequently with isolated infrapopliteal arterial disease relative to other ethnicities, which may contribute to disparate CLI outcomes. Isolated infrapopliteal disease appears to be driven mostly be poorer glycemic control rather than inherent biologic differences between ethnicities. Future studies aimed at understanding disparate outcomes due to race after lower extremity revascularization may benefit from stratification by the severity of diabetes mellitus. Understanding the distribution of atherosclerotic disease may improve the ability to predict outcomes in limb-threatening ischemia.

Genetic Variants in the Transcriptional Regulatory Region of the ALOX5AP gene and Susceptibility to Ischemic Stroke in Chinese Populations.

No coding sequence variants of the ALOX5AP gene that lead to amino acid substitutions have been identified. A two-stage study design was used to explore the relationship between variants in the transcriptional regulatory region of ALOX5AP gene and ischemic stroke (IS) risk in Chinese populations. IS was determined using CT and/or MRI. First, 18 SNPs, located in the upstream promoter region of ALOX5AP gene, were genotyped in 200 IS patients and 200 controls. And one potential associated SNP (rs17222919) was identified (P = 0.005,OR = 0.623, 95% CI: 0.448~0.866). Next, another independent case-control cohort comprising 810 IS patients and 825 matched controls was recruited to investigate the role of rs17222919, rs9579646 polymorphisms and their haplotypes in IS risk. The G allele frequency of rs17222919 in the IS group was significantly lower than that in control group (P = 0.007, OR = 0.792, 95% CI: 0.669~0.937). T-A and G-A haplotypes were associated with IS (P = 0.001,OR = 1.282, 95% CI:1.100~1.495; P = 0.0001, OR = 0.712, 95% CI: 0.598~0.848; respectively). Our study providesevidence that rs17222919 is a potential genetic protective factor against IS. Furthermore, the T-A haplotype is a risk factor and the G-A haplotype is a protective factor against IS in Chinese population.

Poorer limb salvage in African American men with chronic limb ischemia is due to advanced clinical stage and higher anatomic complexity at presentation.

OBJECTIVE: African Americans (AAs) with symptomatic peripheral arterial disease (PAD) have been reported to have fewer revascularization attempts and poorer patency and limb salvage (LS) rates than Caucasians (CAUs). This study compared the outcomes between AA and CAU men with chronic limb ischemia. METHODS: All AA and CAU men who underwent treatment for symptomatic PAD between November 1, 2003, and May 31, 2012, were included. Patency rates, LS, major adverse cardiovascular and limb events, amputation-free survival, and survival were compared before and after propensity score matching and with multivariate (Cox regression) analysis. RESULTS: Of the 834 men (1062 limbs), 107 were AA (137 limbs) and 727 were CAU (925 limbs). AAs were more likely to have insulin-dependent diabetes mellitus, hypertension, dialysis dependence, lower albumin levels, and critical limb ischemia (73% vs 61%; P = .006), whereas CAUs had more coronary artery disease, dyslipidemia, and chronic obstructive pulmonary disease. In patients with critical limb ischemia, primary amputation rates (10.9% vs 7.2%; P = .209) were similar between groups; however, infrapopliteal interventions were more frequent in AAs (62.6% vs 44.3%; P = .004). Perioperative morbidity and mortality rates were similar. Mean follow-up was 38.5 ± 28.9 months (range, 0-119 months). Patency rates, major adverse limb and cardiovascular events, amputation-free survival, and survival were similar in AAs and CAUs; however, the LS rate was significantly lower in AA (73% ± 6% vs 83% ± 2%; P = .048), mainly due to the difference in the endovascular-treated group (5-year LS, 69% ± 7% in AAs vs 84% ± 2% in CAUs; P = .025). All outcomes were similar in propensity score-matched cohorts. In multivariate analysis, insulin-dependent diabetes mellitus, gangrene, poor functional capacity, dialysis-dependence, and need for infrapopliteal revascularization were independently associated with limb loss, whereas race was not. CONCLUSIONS: AA men with symptomatic PAD were found to have lower LS rates than CAUs. However, this was likely due to presenting with advanced ischemia or with poor prognostic factors that are independently associated with limb loss.

Association of Serum Chemerin Levels with Acute Ischemic Stroke and Carotid Artery Atherosclerosis in a Chinese Population.

BACKGROUND: The aim of this study was to examine the association between serum level of chemerin with AIS and carotid artery atherosclerosis, and to investigate the level of chemerin as a potential novel cerebrovascular risk factor. MATERIAL AND METHODS: We compared the serum chemerin levels and cerebrovascular parameters between 70 AIS patients and 70 non-AIS subjects in a Chinese population. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of serum chemerin. The state of carotid artery plaques in the AIS group was detected by color Doppler ultrasound. We used SPSS software for statistical analysis. RESULTS: Compared with the non-AIS group, serum level of chemerin in the AIS group increased significantly (p<0.01). Multivariable logistic regression suggested that serum chemerin level, neutrophil count, and BMI were independent risk factors for AIS (p<0.05). Compared with the non-unstable plaque group, there were significant differences from the unstable plaque group in serum chemerin level (p<0.01). Multivariable logistic regression analysis revealed that the LDL-C, FIB, and serum chemerin levels were independent risk factors for carotid artery plaque instability (P<0.05). The levels of serum chemerin in the subjects with no carotid artery plaque were significantly lower than in those with carotid artery plaques of 2 and ≥3 (P=0.013; P=0.01). CONCLUSIONS: The results of this study suggest that the serum chemerin level may be an independent risk factor for AIS and carotid artery plaque instability in Chinese populations.

Genetic determinants in ischaemic stroke subtypes: seven year findings and a review.

Stroke is a global health problem and a leading cause of disability worldwide. There have been numerable studies undertaking research on different aspects of ischaemic stroke employing various epidemiological, clinical and molecular parameters. Nevertheless ischaemic stroke being a complex disorder with different subtypes demands equal attention towards its subtypes too. Since there has been enough evidence that disposition to certain subtype is genetically determined and there is a distinct mechanism that influences its development, association studies should focus on subtypes simultaneously while studying specific genes. Data from such studies will thus provide better and intricate findings with regard to heterogenous ischaemic stroke. In the present review we discuss the genes studied by our group over a period of seven years in association with stroke subtypes in a South Indian population and correlate the findings with similar genetic studies from other populations so as to provide an overview of various genes involved in the pathogenesis of ischaemic stroke subtypes.

Racial/ethnic disparities in revascularization for limb salvage: an analysis of the National Surgical Quality Improvement Program database.

INTRODUCTION: Previous reports have suggested that black patients have a higher rate of major lower extremity amputation and a lower rate of revascularization for limb salvage when compared to white patients. OBJECTIVE: We undertook this study to determine the extent of this ethnic disparity in recent years and to evaluate whether the widespread adoption of endovascular techniques has had an impact on this disparity. METHODS: The American College of Surgeons' National Surgical Quality Improvement Program (NSQIP) database was queried to identify all patients who had undergone an above- or below-knee amputation as well as all patients who had undergone an open or endovascular revascularization procedure for critical limb ischemia for the years 2005 to 2006. Patient demographics and 30-day outcomes were recorded, and comparisons were made among the different ethnic groups. RESULTS: There were 1568 patients identified in the NSQIP database as having undergone a major lower extremity amputation in 2005 and 2006. Of these patients, 54% were white, 29% black, 8% Hispanic, and 0.7% Asian. Eight percent of patients did not have identifying ethnic data. The group undergoing amputation was primarily male (61%) with a mean age of 65. Median length of stay was 11 days, and 30-day mortality was 9% following amputation. During this same time period, 4191 patients underwent an open surgical procedure and 569 patients underwent an endovascular procedure for the purposes of limb salvage. Of those patients undergoing an open procedure, 74% were white, 12% black, 4% Hispanic, 0.4% Asian, and 10% did not have identifying ethnic data. Open surgical patients were primarily male (63%) with a mean age of 66. Median length of stay was 6 days, and 30-day mortality was 3.3%. Of those patients undergoing an endovascular procedure, 79% were white, 10% black, 2% Hispanic, 1% Asian, and 8% did not have identifying ethnic data. The endovascular group was also primarily male (61%) with a mean age of 68. Median length of stay was 5 days, and 30-day mortality was 4%. CONCLUSION: There remains a significant ethnic disparity in limb-salvage revascularization. Blacks comprise 29% of patients undergoing a major lower extremity amputation, but only 12% of those undergoing an open surgical procedure and 10% of those undergoing an endovascular procedure for limb salvage. The widespread adoption of endovascular revascularization techniques appears not to have had much impact on this disparity.

P-wave morphology and the risk of incident ischemic stroke in the Multi-Ethnic Study of Atherosclerosis.

BACKGROUND AND PURPOSE: Emerging data suggest that left atrial disease may cause ischemic stroke in the absence of atrial fibrillation or flutter (AF). If true, this condition may provide a cause for many strokes currently classified as cryptogenic. METHODS: Among 6741 participants in the Multi-Ethnic Study of Atherosclerosis who were free of clinically apparent cerebrovascular or cardiovascular disease (including AF) at baseline, we examined the association between markers of left atrial abnormality on a standard 12-lead ECG-specifically P-wave area, duration, and terminal force in lead V1-and the subsequent risk of ischemic stroke while accounting for incident AF. RESULTS: During a median follow-up of 8.5 years, 121 participants (1.8%) had a stroke and 541 participants (8.0%) were diagnosed with AF. In Cox proportional hazards models adjusting for potential baseline confounders, P-wave terminal force in lead V1 was more strongly associated with incident stroke (hazard ratio per 1 SD increase, 1.21; 95% confidence interval, 1.02-1.44) than with incident AF (hazard ratio per 1 SD, 1.11; 95% confidence interval, 1.03-1.21). The association between P-wave terminal force in lead V1 and stroke was robust in numerous sensitivity analyses accounting for AF, including analyses that excluded those with any incident AF or modeled any incident AF as having been present from baseline. CONCLUSIONS: We found an association between baseline P-wave morphology and incident stroke even after accounting for AF. This association may reflect an atrial cardiopathy that leads to stroke in the absence of AF.

Racial differences in ischemic complications of pedicled versus free abdominal flaps for breast reconstruction.

PURPOSE: This study aims to determine the relationship between race and ischemic complications in women undergoing breast reconstruction with pedicled TRAM (pTRAM) and perforator flaps (DIEP). PATIENTS AND METHODS: A retrospective, cross-sectional study of women who underwent breast reconstruction utilizing either pTRAM or DIEP flaps from March 1, 2002 to September 1, 2012 was performed. Clinical and demographic variables, including race and ischemic complications (mastectomy flap necrosis, fat necrosis, partial abdominal flap necrosis, vascular compromise requiring reoperation), were examined. Fat necrosis was graded using a previously established scale (grade I = radiologically visible, II = palpable, III = palpable and visible, IV = symptomatic). RESULTS: Over the 10-year study period, adequate follow-up was available for 138 women (94 Caucasian, 36 African American) who underwent pTRAM or DIEP. Fat necrosis occurred more frequently in the pTRAM group (53.5% vs. 17.4%, P < 0.001). There was no statistically significant difference in partial flap necrosis or mastectomy flap necrosis between the 2 groups. The DIEP group had a higher rate of vascular compromise requiring reoperation (13% vs. 0, P = 0.003). In the pTRAM group, there was a higher rate of fat necrosis (77% vs. 45.6%, P < 0.001) and grade IV fat necrosis in African Americans (42.8% vs. 9.5%, P = 0.005). Rates of other ischemic complications were comparable between the 2 racial groups. In the DIEP group, ischemic complications were comparable between the 2 racial groups. After stratifying by flap type and race, we saw no differences in mastectomy flap necrosis (P = 0.0182). DISCUSSION: African Americans undergoing pTRAM flap are at higher risk for grade IV fat necrosis but not mastectomy flap necrosis or partial flap necrosis. This may be due to difficulty using physical examination to judge the vascular status of a pedicle flap that is known to undergo significant changes in vascular physiology following transfer. Intraoperative assessment of perfusion using new technologies may be useful in these higher risk patients.

Association between 9p21 genomic markers and ischemic stroke risk: evidence based on 21 studies.

Epidemiological studies indicate a genetic contribution to ischemic stroke risk, but specific genetic variants remain unknown. Recently independent studies reported an association between coronary heart disease and single-nucleotide polymorphisms (SNPs) located at chromosome 9p21 (rs10757278 and proxy SNPs). Given that stroke is a common complication after myocardial infarction, several validation studies have been conducted among various ethnic populations to investigate if the same loci was associated with ischemic stroke (IS), but the results have been inconsistent. To investigate this inconsistency and derive a more precise estimation of the relationship, a meta-analysis of 34,128 cases and 153,428 controls from 21 studies was performed. Potential sources of heterogeneity including ethnicity, sample size, control source and ischemic stroke subtypes were also assessed. Overall, the summary odds ratio of IS was 1.11 (95% CI: 1.07-1.15, P<10(-5)) for rs10757278. In the subgroup analysis by ethnicity, significantly increased risks were found in East Asians (3188 cases and 4503 controls; OR = 1.14, 95% CI: 1.07-1.21, P<10(-5)) and Caucasians (30505 cases and 145153controls; OR = 1.08, 95% CI: 1.04-1.12, P<10(-5)) for the polymorphism; while no significant associations were found among African Americans (435 cases and 3772 controls; OR = 0.97, 95% CI: 0.63-1.51, P = 0.90) in all genetic models. In the subgroup analyses by IS subtypes, significant association was detected only in large vessel stroke group, while no significant associations among small vessel or cardioembolic stroke. When stratified by sample size, and control source, significantly increased risks were found for the polymorphism in all genetic models. This meta-analysis provides accurate and comprehensive estimates of the association of genetic variant at chromosome 9p21 and IS, but these associations vary in different ethnic populations.

National variation in the utilization of alternative imaging in peripheral arterial disease.

OBJECTIVE: The value and cost-effectiveness of less invasive alternative imaging (AI) modalities (duplex ultrasound scanning, computed tomography angiography, and magnetic resonance angiography) in the care of peripheral arterial disease (PAD) has been reported; however, there is no consensus on their role. We hypothesized that AI utilization is low compared with angiography in the United States and that patient and hospital characteristics are both associated with AI utilization. METHODS: The Nationwide Inpatient Sample (2007-2010) was used to identify patients with an International Classification of Diseases-Ninth Edition diagnosis of claudication or critical limb ischemia (CLI) as well as PAD treatment (surgical, endovascular, or amputation). Patients with AI and those with angiography or expected angiography (endovascular procedures without imaging codes) were selected and compared. Multivariable logistic regression was performed for receiving AI stratified by claudication and CLI and adjusting for patient and hospital factors. RESULTS: We identified 290,184 PAD patients, of whom 5702 (2.0%) received AI. Patients with AI were more likely to have diagnosis of CLI (78.8% vs 48.6%; P < .0001) and receive open revascularizations (30.4% vs 18.8%; P < .0001). Van Walraven comorbidity scores (mean [standard error] 5.85 ± 0.22 vs 4.10 ± 0.05; P < .0001) reflected a higher comorbidity burden in AI patients. In multivariable analysis for claudicant patients, AI was associated with large bed size (odds ratio [OR], 3.26, 95% confidence interval [CI], 1.16-9.18; P = .025), teaching hospitals (OR, 1.97; 95% CI, 1.10-3.52; P = .023), and renal failure (OR, 1.52; 95% CI, 1.13-2.05; P = .006). For CLI patients, AI was associated with black race (OR, 1.53; 95% CI, 1.13-2.08; P = .006) and chronic heart failure (OR, 1.29; 95% CI, 1.04-1.60; P = .021) and was negatively associated with renal failure (OR, 0.80; 95% CI, 0.67-0.95; P = .012). The Northeast and West regions were associated with higher odds of AI in claudicant patients (OR, 2.41; 95% CI, 1.23-4.75; P = .011; and OR, 2.59; 95% CI, 1.34-5.02; P = .005, respectively) and CLI patients (OR, 4.31; 95% CI, 2.20-8.36; P < .0001; and OR, 2.18; 95% CI, 1.12-4.22; P = .021, respectively). Rates of AI utilization across states were not evenly distributed but showed great variability, with ranges from 0.31% to 9.81%. CONCLUSIONS: National utilization of AI for PAD is low and shows great variation among institutions in the United States. Patient and hospital factors are both associated with receiving AI in PAD care, and AI utilization is subject to significant regional variation. These findings suggest differences in systems of care or practice patterns and call for a clearer understanding and a more unified approach to imaging strategies in PAD care.

Racial/ethnic disparities in amputation and revascularization: a nationwide inpatient sample study.

This study investigates whether ethnic minorities presenting with critical limb ischemia (CLI) are more likely to undergo major limb amputation compared to white patients. The Nationwide Inpatient Sample (NIS) database was used to identify all patients admitted with CLI; lower extremity revascularization; and major lower extremity amputation from 1998 to 2005. The NIS identified 240 139 patients presenting with CLI--68.2% white, 19.5% black, 9.0% Hispanic, and 1.24% Asian. In all, 83 328 patients underwent revascularization--73.7% white, 15.9% black, 7.4% Hispanic, and 1.1% Asian. The majority of the interventions were open. In all, 111 548 patients underwent a major lower extremity amputation--61% white, 25.4% black, 10.1% Hispanic, and 1.1% Asian. The mean Charlson comorbidity scores for amputation were 2.1 for whites, 2.0 for blacks, 2.3 for Hispanics, and 2.5 for Asians (for all data, P < .05). Blacks make up a disproportionately higher proportion of patients admitted for CLI and undergoing amputation, with a lower proportion undergoing revascularization.

Antiphospholipid syndrome in a young Nigerian girl presenting with gangrenous toes.

We report on a 21-year-old Nigerian girl with toe gangrene, which is one of the most unlikely forms of presentation of antiphospholipid syndrome among Africans. The essence of this case report is to raise awareness that, although antiphospholipid syndrome typically presents in Africans in association with a pregnancy-related event or a neuropathology, it should be considered as a differential diagnosis in all African patients with unexplained vasculitis. A high index of suspicion and early treatment will prevent toe amputations and reduce mortality rates.

[Association of matrix metalloproteinase-3 gene polymorphisms with subtypes of ischemic stroke].

OBJECTIVE: To assess the association between matrix metalloproteinase-3 (MM-3) gene polymorphisms and subtypes of ischemic stroke (IS) in northern Han Chinese population. METHODS: A total of 289 patients with acute IS (within 3 days after the onset, including 185 with large artery atherosclerosis (LAA) and 104 for small artery occlusion (SAO)) and 175 matched healthy controls were recruited for this case-control study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) or sequenc-based typing (SBT) was carried out to analyze 3 SNPs of the MMP-3 gene. RESULTS: An incomplete linkage disequilibrium (LD) block was constructed with the 3 SNPs, and the distribution of genotypes of the 3 SNPs differed between the LAA group and controls in a dominant model: Carriers of 5A allele (5A5A+5A6A) of the rs3025058 locus were 1.72 times more susceptible to LAA stroke compared with carriers of 6A6A alleles (P=0.017, OR=1.72, 95% CI: 1.10-2.69), carriers of G alleles (GG+AG) of the rs522616 locus were 0.52 times more susceptible to LAA stroke compared with carriers of AA alleles (P=0.005, OR=0.52, 95% CI: 0.33-0.82), whilst carriers of A allele of the rs679620 locus were 1.55 times more susceptible to LAA stroke compared with carriers of GG alleles (P=0.042, OR=1.55, 95% CI: 1.01-2.37). However, no significant difference has been found between particular genotypes of such SNPs between SAO patients and controls (P> 0.05). Furthermore, 5A-A-A and 6A-A-A haplotypes were significantly more common in LAA group than the controls (P< 0.05), whilst 6A-G-G haplotype has been the opposite (P< 0.01). CONCLUSION: Our study has demonstrated that serum MMP-3 level is significantly increased at acute stage of LAA as well as SAO type strokes. There may be an association of rs3025058, rs522616 and rs679620 of MMP-3 gene with susceptibility to LAA stoke in northern Han Chinese population.