The antiphospholipid syndrome - often overlooked cause of vascular occlusions?

The antiphospholipid syndrome (APS) was fully recognized as a clinical entity in the early 1980s. Still, more than 30 years later, the epidemiology of APS is not well described, and furthermore, APS remains a challenge in terms of both diagnostic issues and clinical praxis involving a wide range of specialties. To date, there are no diagnostic criteria for APS. The present classification criteria rely on a combination of clinical manifestations and persistently positive tests for antiphospholipid antibodies (aPL). Clinical symptoms comprise vascular thrombosis, which can affect any vascular bed, including venous, microvascular and arterial vessels, and a set of pregnancy morbidities including early and late miscarriages, foetal death and preeclampsia. APS is more frequent among patients with other autoimmune diseases, and it is especially common in systemic lupus erythematosus (SLE). Importantly, APS symptoms can present in almost any medical specialty, but general knowledge and most previous clinical studies have essentially been confined to haematology, rheumatology and obstetrics/gynaecology. However, recent data demonstrate a relatively high prevalence of aPL also in patients from the general population who suffer from vascular occlusions or pregnancy complications. It is important that these patients are recognized by the general health care since APS is a treatable condition. This review aims to summarize the present knowledge on the history, pathogenesis, clinical manifestations and treatment of APS in order to urge a wide range of clinicians to consider comprehensive assessment of all patients where the diagnosis APS may be conceivable.

Genome-Wide Association Transethnic Meta-Analyses Identifies Novel Associations Regulating Coagulation Factor VIII and von Willebrand Factor Plasma Levels.

BACKGROUND: Factor VIII (FVIII) and its carrier protein von Willebrand factor (VWF) are associated with risk of arterial and venous thrombosis and with hemorrhagic disorders. We aimed to identify and functionally test novel genetic associations regulating plasma FVIII and VWF. METHODS: We meta-analyzed genome-wide association results from 46 354 individuals of European, African, East Asian, and Hispanic ancestry. All studies performed linear regression analysis using an additive genetic model and associated ≈35 million imputed variants with natural log-transformed phenotype levels. In vitro gene silencing in cultured endothelial cells was performed for candidate genes to provide additional evidence on association and function. Two-sample Mendelian randomization analyses were applied to test the causal role of FVIII and VWF plasma levels on the risk of arterial and venous thrombotic events. RESULTS: We identified 13 novel genome-wide significant ( P≤2.5×10-8) associations, 7 with FVIII levels ( FCHO2/TMEM171/TNPO1, HLA, SOX17/RP1, LINC00583/NFIB, RAB5C-KAT2A, RPL3/TAB1/SYNGR1, and ARSA) and 11 with VWF levels ( PDHB/PXK/KCTD6, SLC39A8, FCHO2/TMEM171/TNPO1, HLA, GIMAP7/GIMAP4, OR13C5/NIPSNAP, DAB2IP, C2CD4B, RAB5C-KAT2A, TAB1/SYNGR1, and ARSA), beyond 10 previously reported associations with these phenotypes. Functional validation provided further evidence of association for all loci on VWF except ARSA and DAB2IP. Mendelian randomization suggested causal effects of plasma FVIII activity levels on venous thrombosis and coronary artery disease risk and plasma VWF levels on ischemic stroke risk. CONCLUSIONS: The meta-analysis identified 13 novel genetic loci regulating FVIII and VWF plasma levels, 10 of which we validated functionally. We provide some evidence for a causal role of these proteins in thrombotic events.

Distribution and Temporal Trends From 1993 to 2015 of Ischemic Stroke Subtypes: A Systematic Review and Meta-Analysis.

BACKGROUND AND PURPOSE: Preventive strategies, together with demographic and socioeconomic changes, might have modified the worldwide distribution of ischemic stroke (IS) subtypes. We investigated those changes by means of a systematic review and meta-analysis. METHODS: We evaluated all population- and hospital-based studies reporting the distribution of IS etiologic subtypes according to the TOAST criteria (Trial of ORG 10172 in Acute Stroke Treatment). Studies were identified by searching articles indexed on PubMed and Scopus from January 1, 1993, to June 30, 2017. Two independent investigators extracted data and checked them for accuracy. Proportions of each etiologic subtype were pooled according to a random effect meta-analytic model weighted by study size; temporal trends were assessed using a mixed-effect meta-regression model. RESULTS: Sixty-five studies including patients from 1993 to 2015 were finally included. Overall, ISs were attributed to cardioembolism (22%; 95% confidence interval [CI], 20-23); large artery atherosclerosis (23%; 95% CI, 21-25); small artery occlusion (22%; 95% CI, 21-24); other determined cause (3%; 95% CI, 3-3); and undetermined cause (26%; 95% CI, 24-28). Cardioembolism was the leading IS etiologic subtype in whites (28%; 95% CI, 26-29) and large artery atherosclerosis in Asians (33%; 95% CI, 31-36). Meta-regression showed an increasing temporal trend for cardioembolism in whites (2.4% annually, P=0.008) and large artery atherosclerosis in Asians (5.7% annually, P<0.001), and a decrease for small artery occlusion in whites (-4.7% annually, P=0.001); there was considerable heterogeneity across all the analyses. CONCLUSIONS: According to our systematic review and meta-analysis, cardioembolism in whites and large artery atherosclerosis in Asians are the leading causes of IS. The heterogeneous distribution of etiologic subtypes of IS may depend on the demographic and socioeconomic characteristics of the different populations. More extensive protocols should be adopted to reduce the persistently relevant proportion of undetermined cause IS.

Impact of sheath size and hemostasis time on radial artery patency after transradial coronary angiography and intervention in Japanese and non-Japanese patients: A substudy from RAP and BEAT (Radial Artery Patency and Bleeding, Efficacy, Adverse evenT) randomized multicenter trial.

BACKGROUND: During transradial (TR) access, it remains unclear whether differences in baseline patients characteristics and hemostasis care impact the rate of radial artery occlusion (RAO). We sought to compare the rate of RAO after TR access with the 6 French(Fr) Glidesheath Slender (GSS6Fr, Terumo, Japan) or a standard 5 Fr sheath in Japanese and non-Japanese patients. METHODS AND RESULTS: The Radial Artery Patency and Bleeding, Efficacy, Adverse evenT (RAP and BEAT) trial randomized 1,836 patients undergoing TR coronary angiography and/or interventions to receive the GSS6Fr or the standard 5 Fr Glidesheath (GS5Fr, Terumo, Japan). Out of this study population, 1,087 were Japanese patients and 751 non-Japanese patients. The overall incidence of RAO was significantly higher in Japanese patients (3.6% vs. 1.2%, P = 0.002). Use of GSS6Fr was associated with higher rates of RAO than GS5Fr in Japanese patients (5% vs. 2.2%, P = 0.02) and with similar RAO rates in non-Japanese patients (1.3 vs. 1.1%, P = 1). The mean hemostasis time was significantly longer in Japanese patients (378 ± 253 vs. 159 ± 136 min, P < 0.001) and more Japanese patients had a hemostasis time of more than 6 hr (16.2% vs. 4.9%, P < 0.0001). Longer hemostasis time was an independent predictor of RAO (OR per additional hour 1.070, 95% CI 1.008-1.136, P = 0.03). CONCLUSIONS: Use of GSS6Fr was associated with a higher rate of RAO than a standard 5 Fr sheath in Japanese patients but not in non-Japanese patients. Whether improvement in post-procedural care and reduced hemostasis time could impact the incidence of RAO in Japanese patients should be further assessed.

Potential risk for intra-aortic balloon-induced obstruction to the celiac axis or the renal artery in the Asian population.

To evaluate the potential risk for intra-aortic balloon (IAB)-induced obstruction to the celiac axis (CA) or the renal artery (RA) when IAB size is chosen according to patient height and the tip is placed 2 cm distal to the origin of the left subclavian artery (LSCA), the computed tomography images of 150 Asian adults were reviewed to identify the distance from the LSCA to the CA (LSCA-CA) and to the RA (LSCA-RA). The diameter of the aorta at the level of the T9 vertebra, CA, and RA was also measured. The length and caliber of the IAB was selected according to two manufacturer's recommendations (Datascope Corp and Tokai Medical Products). The Datascope IAB potentially blocked the CA in 84 % and the RA in 66 %, while the Tokai IAB obstructed the CA in 61 % and the RA in 10 % of cases. The caliber of the IAB overlying the orifice of the RA was longer than the diameter of the aorta in 5 cases (3.3 %) using the Datascope IAB, and in 1 case (0.7 %) using the Tokai IAB. When placing an IAB selected based on patient height, the IAB could obstruct the orifice of the CA and RA in the majority of Asian patients, especially a Datascope IAB.

Impact of race on infrainguinal angioplasty and stenting.

BACKGROUND: Over the last decade, catheter-based interventions on lower extremity arteries have been used with increasing frequency. However, the effect of racial background on the outcome of lower extremity endovascular interventions for peripheral arterial disease is unknown. The purpose of this study was to determine the effect of patients' race on the durability of angioplasty and stenting performed on the superficial femoral and popliteal arteries. METHODS: The records of all patients undergoing percutaneous intervention on the lower extremity arteries during a 14-year period were reviewed. During a 44-month period (2003-2007), all patients underwent primary stenting as part of a prospective study protocol. Indication for intervention, TransAtlantic InterSociety Consensus II classification, runoff anatomy, site of intervention, and the placement of stents were noted. Results were analyzed by race. Kaplan-Meier life survival curves were plotted and differences between groups tested by log-rank method. Cox proportional hazards regression model was used to perform the multivariate analysis. RESULTS: Between 1994 and 2007, a total of 374 percutaneous interventions were performed on the superficial femoral and popliteal arteries in 280 patients. Of these, 182 procedures were angioplasties and 192 included both angioplasty and stenting. The study group consisted of 60% Caucasians, 23% Hispanics, 12% African Americans, and 5% Asians. No difference in primary patency rates was noted between individuals belonging to different races. However, in those undergoing angioplasty alone, Caucasians had the highest rate of failure, followed by Hispanics, African Americans, and then Asians (p < 0.002). No difference in patency rates between races was seen in patients undergoing angioplasty with stenting. For the entire group, dyslipidemia, TransAtlantic InterSociety Consensus II C and D lesions, and angioplasty without stenting negatively affected primary patency. CONCLUSIONS: Race does not appear to influence the durability of catheter-based procedures performed on the superficial femoral and popliteal arteries. However, in patients who underwent angioplasty alone, it was noted that Caucasians had the highest rates of failure and Asians the lowest. However, this difference was no longer apparent when stents were used.

Basilar artery occlusive disease in stroke survivors in a multiethnic population.

OBJECTIVES: To describe clinical, radiological findings, and outcome in a multiethnic population of stroke survivors with basilar artery occlusive disease (BAOC). METHODS: Forty patients with infarcts in the basilar artery (BA) territory, alive 30 days after the ictus, participated in the study. BA stenosis (>50%) or occlusion was shown by magnetic resonance or digital subtraction angiography in all patients. Demographical, clinical and radiological characteristics were described. Modified Rankin Scale (MRS) scores at 30 days and 6 months after the ischemic event were evaluated. Association between demographical, clinical, radiological features and outcome were analyzed with Chi-square and Fisher's exact tests. MRS scores at 30 days and 6 months were compared with the Wilcoxon test. RESULTS: Sixty percent of the patients were men, and 33% were Afro-Brazilian. Mean age was 55.8+/-12.9 years. Most (90%) had multiple vascular risk factors. Stroke was preceded by TIA in 48% of the patients, and 80% had a history of arterial hypertension. The most common neurological symptom was vertigo/dizziness (60%) and the sign, hemiparesis (60%). Most of the infarcts were located in the pons (85%) and the BA middle third was the most frequently affected segment (33%). BA occlusion occurred in 58% of the patients. More severe vascular occlusive lesions were present in Whites (p=0.002) and in patients with involvement of the middle third of the BA (p=0.021). Large-artery atherosclerosis was the most common stroke etiology (88%) and was more frequent in older patients (p<0.001). Most patients were treated with anticoagulation. MRS scores improved significantly at 6 months (p<0.001); at this time, 78% of the patients had MRS scores between 0 and 2. CONCLUSIONS: We observed different results compared with other series: greater proportion of Afro-descendents, higher frequency of atherosclerosis and BA occlusion. Rates of preceding TIAs and good outcome at 6 months were similar to previously published data. These results represent a step forward towards understanding BAOC in a multiethnic context.

Impact of atherosclerotic risk factors on the extent of arterial occlusive disease among Arabian patients: a hospital based study.

AIM: Although the risk factors for atherosclerosis have been identified, their impacts on the extent of arterial occlusive disease among Arabian population have never been studied before. METHODS: A case control study was undertaken on consecutive series of Arabian patients over one year. The study comprised 2 patients groups: atherosclerotic group which included patients aged 40 years and older admitted with peripheral, carotid or coronary artery disease and the control group, including patients admitted to one of the general surgical units who were free from atherosclerotic disease. All patients underwent evaluation of risk factors for atherosclerotic and systemic study of the vascular tree. Correlation and association were checked between prevalence of these factors and the extent of atherosclerotic disease into different territories. RESULTS: Two hundred and fifteen patients in the atherosclerotic group and 191 patients in the control group were included. The incidence of diabetes mellitus (DM) was very high in the atherosclerotic group (67.8%). There was significant correlation between incidence of risk factors and risk and extent of atherosclerosis. In age, sex and nationality-adjusted logistic regression analysis, combination of some risk factors augmented the risk and extent of atherosclerosis e.g. diabetes alone increased the risk of atherosclerosis slightly in one affected system (OR 2.28, 95% CI 1.9-2.7) while combination of diabetes, smoking and dyslipidemia enhanced this risk (OR 7.4, 95% CI 2.5-22.4). CONCLUSIONS: The risk factors of atherosclerosis increase its incidence and extent into different territories.

Alanine aminotransferase is associated with atherothrombotic risk factors in a British South Asian population.

BACKGROUND: Alanine aminotransferase (ALT) predicts the development of Type 2 diabetes mellitus and cardiovascular disease in Caucasian subjects. OBJECTIVES: This study aimed to determine the incidence of an elevated ALT and its relationship to metabolic and atherothrombotic risk factors in a healthy British South Asian population. PATIENTS/METHODS: One hundred and forty-three participants from the West Yorkshire community were recruited randomly from general practice registers and were grouped according to whether their ALT was above or within the normal range (cut-off 35 IU L(-1)) and examined for differences in metabolic and atherothrombotic risk factors. All participants were originally from South Asia, with their grandparents being born in India, Pakistan, or Bangladesh. RESULTS: The incidence of a raised ALT was 24%. Those with a raised ALT had a more adverse metabolic profile, with significantly higher body mass index, waist/hip ratio, fasting insulin, glucose, homeostasis model assessment homeostasis model assessment insulin resistance (HOMA-IR), and triglycerides, and lower high-density lipoprotein (HDL) cholesterol. Fifty per cent had the metabolic syndrome [International Diabetes Federation (IDF) criteria]. They also had a more adverse atherothrombotic profile, with higher tissue-type plasminogen activator and plasminogen activator inhibitor-1 (PAI-1) antigen. In accordance, the group as a whole showed a positive correlation of ALT (age-adjusted) with waist/hip ratio, insulin, glucose, triglycerides, PAI-1 antigen, factor XIII B subunit, and FXII, and a negative correlation with HDL cholesterol. CONCLUSION: Raised ALT is common in apparently healthy British South Asians, and is significantly associated with an adverse metabolic and atherothrombotic risk profile.

Clinical profile of sickle cell disease in Yemeni children.

UNLABELLED: The clinical spectrum of sickle cell disease (SCD) in the Arabian Peninsula varies widely. This is the first report in Yemeni children. METHODS: A hospital-based, cross-sectional study was undertaken in Al-Wahada Teaching Hospital in Aden of children under 16 years with homozygous (SS) SCD. RESULTS: Fifty-six (55%) were males. There were clinical manifestations in 20% by the age of 6 months and in 67%, 88% and 92% by 1, 2 and 3 years, respectively. Dactylitis (hand-foot syndrome) was the most common presenting symptom and occurred in 54% of cases, followed by acute respiratory infections and other acute febrile illnesses. The main causes of hospitalisation were painful crisis (36%), anaemic crisis (16%) and acute chest syndrome (11%). Hepatomegaly was detected in 72% and splenomegaly in 40%. Cerebrovascular accident, cholelithiasis, hepatic crisis and leg ulcers each occurred in about 5% of patients. There was first- and second-degree consanguinity in 31% and 16%, respectively, of patients' families. CONCLUSION: SCD is a serious problem, affecting children in Yemen from an early age. Disease course and severity were similar to that in Africans and American blacks and some reports from western Saudi Arabia. A screening programme linked to comprehensive medical care and genetic counselling is required to improve management and quality of life.

Diagnosis of congenital obstructive aortic arch anomalies in Chinese children by contrast-enhanced magnetic resonance angiography.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of contrast-enhanced magnetic resonance angiography for the diagnosis of congenital obstructive aortic arch anomalies in children and compare it with transthoracic echocardiography and other MR imaging techniques (ECG gated T1-weighted spin-echo imaging and gradient-echo cine imaging). MATERIALS AND METHODS: Contrast-enhanced magnetic resonance angiography, ECG gated T1-weighted spin-echo imaging, and gradient-echo cine imaging were performed for the diagnosis of congenital obstructive aortic arch anomalies in 416 patients from April 1999 to March 2005 (age range, 3 days to 12 years; mean age, 2.4 years) using a GE 1.5T MR scanner. Transthoracic echocardiography was performed in all patients prior to MR examination. Surgery and/or conventional X-ray angiocardiography were done in all patients to determine the final diagnosis. RESULTS: The population consisted of 416 patients. Congenital obstructive aortic arch anomalies were diagnosed in 213 patients and ruled out in 203 patients by operation and/or conventional X-ray angiocardiography. Among the 213 patients with anomalies, coarctation of aorta was diagnosed in 174, interruption of aortic arch was diagnosed in 35, and persistent fifth aortic arch with fourth aortic arch interruption was diagnosed in 4 patients. Among the 35 patients with interruption of aortic arch, 21 were of type A, and 14 were of type B. The diagnostic sensitivity, specificity and accuracy of contrast-enhanced magnetic resonance angiography for congenital obstructive aortic arch anomalies were 98% (208/213), 99% (201/203) and 98% (409/416), respectively. The diagnostic sensitivity, specificity and accuracy of transthoracic echocardiography were 88% (187/213), 92% (186/203) and 90% (373/416), respectively. The diagnostic sensitivity, specificity and accuracy of other MR imaging techniques (ECG gated T1-weighted spin-echo imaging and gradient-echo cine imaging) were 89% (189/213), 84% (170/203) and 86% (359/416), respectively. CONCLUSION: Contrast-enhanced magnetic resonance angiography is a reliable, noninvasive imaging technique for the diagnosis of congenital obstructive aortic arch anomalies in children. Occasionally, even more information can be obtained from this technique than from conventional X-ray angiocardiography. Contrast-enhanced magnetic resonance angiography is superior to transthoracic echocardiography and other MR imaging techniques (ECG gated T1-weighted spin-echo imaging and gradient-echo cine imaging) for diagnosis of congenital obstructive aortic arch anomalies in children.

Comparative analysis of autogenous infrainguinal bypass grafts in African Americans and Caucasians: the association of race with graft function and limb salvage.

OBJECTIVE: African Americans (AAs) are at risk for developing diabetes mellitus and atherosclerosis. Whether race influences the results of infrainguinal arterial reconstruction is unclear. The purpose of this study was to compare the results of autogenous infrainguinal bypasses in AAs and Caucasians to determine the association of race with graft function and limb salvage. METHODS: This was a retrospective, comparative cohort study of AA and Caucasian patients who had undergone autogenous infrainguinal bypass surgery. Only single-limb bypasses in each patient cohort were considered in this analysis. In patients who had undergone bilateral lower limb bypasses, the first limb bypass was chosen as the index bypass procedure. RESULTS: From January 1985 to December 2003, 1459 autogenous infrainguinal bypasses were performed in 1459 patients for lower limb ischemia. Within this group, 89 AA patients/vein grafts formed the study cohort. The control group comprised 1370 Caucasian patients/vein grafts. Compared with the Caucasian cohort, AA patients were significantly younger (median age, 65 vs 70 years, respectively; P = .001) and predominantly female (57% vs 41%, respectively; P = .002). AA patients also had a higher prevalence of diabetes mellitus, hypertension, cerebrovascular disease, congestive heart failure, and dialysis-dependent renal failure. More AA than Caucasian patients presented with gangrene (34% vs 16%, respectively; P = .001), and more underwent bypass surgery for limb salvage indications (91% vs 81%, respectively; P = .01). The venous conduit used was predominantly the greater saphenous vein (AA, 83%; Caucasian, 85%), and the site of distal anastomosis was at the tibial/pedal level in 67% of AA and 61% of Caucasian patients. Overall morbidity (AA, 28%; Caucasian, 23%) and 30-day mortality (AA, 3%; Caucasian, 3%) were similar. Thirty-day graft failure was significantly greater in AAs than Caucasians (12% vs 5%, respectively; P = .003). The overall 5-year primary graft patency (+/-SE) was significantly worse in AA patients (AA, 52% +/- 6%; Caucasian, 67% +/- 2%; P = .009). The 5-year limb salvage rate (+/-SE) was also significantly worse in AA patients (AA, 81% +/- 5%; Caucasian, 90% +/- 1%; P = .04). With the Cox proportional hazard model, significant risk factors associated with primary graft failure were AA race, age younger than 65 years, female sex, secondary reconstructions, tibial bypasses, and critical limb ischemia. Significant risk factors associated with limb loss were age younger than 65 years, female sex, absence of coronary disease, presence of critical limb ischemia, and secondary reconstructions. CONCLUSIONS: Autogenous infrainguinal bypass surgery in AAs is associated with poorer primary graft patency and limb salvage rates compared with those of Caucasians. This may partially account for the higher rate of limb loss in AA patients with peripheral arterial occlusive disease.

Independent association of uric acid levels with peripheral arterial disease in Taiwanese patients with Type 2 diabetes.

AIMS: Hyperuricaemia may be a risk factor for atherosclerotic disease. Its association with peripheral arterial disease (PAD) has not been studied in Taiwanese patients with Type 2 diabetes. METHODS: Uric acid (UA) levels and PAD were evaluated in 508 Taiwanese outpatients with Type 2 diabetes (210 men, 298 women; mean age +/- sd, 63.8 +/- 10.6 years). PAD was diagnosed when the ankle-brachial index was < 0.9. Patients with an ankle-brachial index of > or = 1.3 were excluded because of possible medial arterial calcification. Potential confounding variables with P < 0.10 were adjusted for in multivariate analyses. RESULTS: In univariate analyses, UA levels were higher in patients with PAD than in those without PAD (345.0 +/- 95.2 vs. 309.3 +/- 89.2 micromol/l; P < 0.0005). Prevalences of PAD for quintiles of UA levels were 6.8, 8.9, 10.2, 13.1 and 16.5%, respectively (P-trend < 0.05). With UA level as a continuous variable, the multivariate-adjusted odds ratio (95% confidence interval) for PAD was 1.005 (1.001-1.008) (P < 0.01). The optimal cut-off point for UA as determined by the receiver operating characteristic curve was 264.7 micromol/l. The sensitivity and specificity at this cut-off point was 82.6 and 33.3%, respectively. The area under curve was 0.60 (95% confidence interval: 0.53-0.68). The multivariate-adjusted odds ratio for PAD for UA above this level was 2.736 (1.239-6.043) (P < 0.05). The results after excluding 56 cases using diuretics were similar. CONCLUSIONS: Elevated uric acid level is a significant and independent risk factor for PAD in Taiwanese patients with Type 2 diabetes.

Lower extremity nontraumatic amputation among veterans with peripheral arterial disease: is race an independent factor?

OBJECTIVES: To determine if race/ethnicity is independently associated with an increased risk for nontraumatic lower extremity amputation versus lower extremity bypass revascularization among patients with peripheral arterial disease (PAD). METHODS: Data were analyzed from the National VA Surgical Quality Improvement Program (NSQIP) and from the Veterans Affairs Patient Treatment File (PTF). Race/ethnicity was defined as non-Hispanic white, black, or Hispanic. Variables that were univariately associated (P < or = 0.05) with the outcome of amputation were placed into a multiple logistic regression model to determine independent predictors for the dependent variable, lower extremity amputation versus lower extremity bypass revascularization. RESULTS: Three thousand eighty-five lower extremity amputations and 8409 lower extremity bypass operations were identified. Among all cases included, there were 416 Hispanic patients (3.6%), 2337 black patients (20.3%), and 8741 non-Hispanic white patients (76.1%). Among all variables within the model, Hispanic and black race were each associated with a greater risk for amputation than a history of rest pain/gangrene (Hispanic race 1.4, 95% CI 1.1, 1.9; black race 1.5, 95% CI 1.4, 1.7; rest pain/gangrene 1.1, 95% CI 1.0, 1.3). The final model had a c statistic of 0.83. CONCLUSION: Hispanic race and black race were independent risk factors for lower extremity amputation in patients with PAD. Although the burden of certain atherosclerotic risk factors (eg, diabetes and hypertension) is higher in minority patients, the impact of this burden does not account for the increased risk for the outcome of lower extremity amputation in these two populations. Further research is needed to better understand the reason(s) why race/ethnicity is independently associated with poor outcomes in PAD.

Aorto-iliac occlusive disease in the different population groups--clinical pattern, risk profile and results of reconstruction.

BACKGROUND: It has previously been accepted that atherosclerotic disease is uncommon among blacks worldwide; however, recent studies have increasingly reported atherosclerotic disease in this group. STUDY DESIGN: Prospective study of hospital patients with aorto-iliac occlusive disease presenting to the vascular service of the Durban metropolitan hospitals. The study was designed to assess clinical pattern, risk profile and results of reconstruction in these patients. METHODS: This is a study of 688 patients with aorto-iliac occlusive disease managed over 9 years in Durban, with clinical pattern and risk factors compared in the different population groups. A subgroup of 492 patients underwent aortobifemoral bypass, providing material for comparison of the results of reconstruction in the different population groups. RESULTS: More black patients presented with gangrene and threatened limb, whereas whites tended to present early with claudication. All groups had hypertension and diabetes as risk factors. In addition, whites and Indians had ischaemic heart disease, which was not found among blacks. Mortality was 5% (blacks 1.8%, whites 8.5%, Indians 5%). Medium-term occlusion rates were 19% in blacks, 13% in Indians and 5% among whites. Five-year cumulative patency rates were 92% for whites, 77% for Indians and 74% for blacks. CONCLUSION: Whites do significantly better than blacks, who tend to present at an advanced stage of the disease. The presence of ischaemic heart disease among whites and Indians contributes to the higher mortality in these groups.

Intracranial stenosis in Chinese patients with acute stroke.

We studied 100 consecutive acute stroke patients in a Chinese population with transcranial Doppler and CT. Twenty patients had intracerebral hemorrhage and 14 patients did not have adequate temporal windows for transcranial Doppler examination. Among the remaining 66 patients, 22 patients (33%) had intracranial occlusive diseases and 3 (6%) had extracranial carotid stenosis. Our data showed that intracranial occlusive disease is the most commonly found vascular lesion in our acute stroke patients.