Iliac Vein Compression Syndrome in an Asymptomatic Patient Population: A Prospective Study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Iliac vein compression syndrome (IVCS) is an important cause of deep vein thrombosis, but the incidence of IVCS is still unclear. The purpose of this prospective study was to determine the incidence of IVCS in an asymptomatic patient population and to evaluate the risk factors in patients with and without IVCS.</p><p><b>METHODS</b>From October 2011 to November 2012, a total of 500 patients (228 women and 272 men; mean age of 55.4 ± 14.7 years) with no vascular-related symptoms were enrolled in this study. Computed tomography was performed to evaluate all patients. The degree of venous compression was calculated as the diameter of the common iliac vein at the site of maximal compression divided by the mean diameter of the uncompressed proximal and caudal left common iliac vein (LCIV). We compared the stenosis rate of the common iliac vein in women and men according to age and followed up patients to evaluate outcomes.</p><p><b>RESULTS</b>The mean compression degree of the LCIV was 16% (4%, 36%); 37.8% of patients had a compression degree ≥25% and 9.8% had a compression degree ≥50%. There was a significant difference between men and women in the LCIV compression degree (9% [3%, 30%] vs. 24% [8%, 42%]; U = 4.66, P< 0.01). In addition, the LCIV compression degree among younger women (≤40 years) was significantly different compared with that in older women (>40 years) (42% [31%, 50%] vs. 19% [5%, 39%]; U = 5.14, P< 0.001). Follow-up was completed in 367 patients with a mean follow-up of 39.5 months (range, 6-56 months). The incidence of IVCS in the follow-up period was 1.6%. Stenosis rate and the diameter of the site of maximal compression correlated with the incidence of IVCS. Multivariable Cox regression analysis showed that the stenosis rate was an independent risk factor of IVCS (Wald χ2 = 8.84, hazard ratio = 1.13, P< 0.001).</p><p><b>CONCLUSIONS</b>The incidence of IVCS was low and correlated with the stenosis rate of iliac vein. Preventative therapy may be warranted for common iliac vein compression in patients at an increased risk of venous thromboembolism, especially patients with a higher iliac vein compression degree.</p>

Incidence and Risk Factors of Deep Venous Thrombosis in Asymptomatic Iliac Vein Compression: A Prospective Cohort Study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Deep vein thrombosis (DVT) may be associated with iliac vein compression. Up to now, the majority of data has come from a retrospective study about the correlation between DVT and iliac vein compression. This prospective study was to determine the incidence of DVT in individuals with iliac vein compression and identify risk factors predictive of DVT.</p><p><b>METHODS</b>A total of 500 volunteers without symptoms of venous diseases of lower extremities and overt risk factors of deep venous thrombosis between October 2011 and September 2012 in Shijitan Hospital were enrolled in this cohort study. All the participants underwent contrast-enhanced abdominal computed tomography (CT) to evaluate iliac vein compression. Baseline demographic information and degree of iliac vein compression were collected. They were categorized into ≥50% or <50% iliac vein compression group. Ultrasound examination was performed to screen DVT at the time of CT examination and 3, 6, 9, and 12 months after the examination. Primary event was DVT of ipsilateral lower extremity. Correlation between DVT and iliac vein compression was estimated by multivariate Logistic regression after adjusting for age, gender, malignancy, surgery/immobilization, chemotherapy/hormonal therapy, and pregnancy.</p><p><b>RESULTS</b>In 500 volunteers, 8.8% (44) had ≥50% iliac vein compression and 91.2% (456) had <50% iliac vein compression. Ipsilateral DVT occurred in six volunteers including two in iliofemoral vein, two in popliteal vein, and two in calf vein within 1 year. Univariate analysis showed that the incidence of DVT was 6.8% in ≥50% compression group, significantly higher than that in <50% compression group (0.7%) (χ2 = 12.84, P = 0.01). Patients with malignancy had significantly higher incidence of DVT than those without malignancy (χ2 = 69.60,P< 0.01). Multivariate Logistic regression indicated that iliac vein compression and malignancy were independent risk factors of DVT. After adjustment for malignancy, patients with ≥50% iliac vein compression had 10-fold increased risk of developing DVT (adjusted relative risk [RR] = 10.162, 95% confidence interval [CI]: 1.149-89.865, P = 0.037). In subgroup analysis, patients with malignancy and ≥50% iliac vein compression had 12-fold increased the risk of DVT than those without malignance and ≥50% compression (RR = 12.389, 95% CI: 2.327-65.957, P = 0.003).</p><p><b>CONCLUSIONS</b>Iliac vein compression is common, but the incidence of DVT is low. Only individuals with ≥50% iliac vein compression or compression combined with other risk factors might have significantly increased the risk of DVT. Further study is recommended to improve prevention strategies for DVT in significant iliac vein compression.</p>

A prospective randomized control clinical trial about clopidogrel combined with warfarin versus clopidogrel alone in the prevention of restenosis after femoral-popliteal artery angioplasty / 中华外科杂志

<p><b>OBJECTIVE</b>Using two antithrombotic treatment (clopidogrel vs. clopidogrel combined warfarin) strategies after femoral-popliteal artery angioplasty prospectively, to evaluate which strategy is more effective for the restenosis prevention.</p><p><b>METHODS</b>Totally 50 patients referred for endovascular treatment (including the percutaneous transluminal angioplasty (PTA) and stent implantation) of the superficial femoral artery and popliteal artery from January 2008 to May 2009 were randomly divided into clopidogrel group (group A, 25 cases, 30 limbs) and clopidogrel plus warfarin group (group B, 25 cases, 33 limbs) before operation. Clinical outcomes and restenosis rate of the target lesions were evaluated at 3, 6 and 12 months after operation.</p><p><b>RESULTS</b>Totally 88 patients were screened for participation in the study, 56 patients were included after the follow-up of 12 months. At 3 months, the rates of restenosis were 16.7% in group A and 18.2% in group B (χ² = 0.025, P = 0.874). At 6 months, the accumulated restenosis rates were 36.7% in group A and 36.4% in group B (χ² = 0.001, P = 0.98). At 12 months, the accumulated restenosis rates were 53.3% in group A and 42.4% in group B (χ² = 0.75, P = 0.387). Analysis for the critical limb ischemia sub-group showed that follow-up of 12 months, the accumulated restenosis rate was 8/10 in group A and 6/12 in group B (χ² = 1.023, P = 0.312).</p><p><b>CONCLUSION</b>The clopidogrel alone treatment for PTA or PTA plus stent implantation of femoral popliteal artery has no statistically significant difference in comparison with the clopidogrel combined warfarin treatment in terms of the cumulative vascular restenosis rate at 3, 6, 12 months postoperatively.</p>

Application of cerebral protection to carotid endarterectomy at perioperation, intraoperation, and postoperation / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the significance of cerebral protection applied at carotid endarterectomy (CEA) at perioperation, intraoperation, and postoperation.</p><p><b>METHODS</b>Thirty patients underwent CEA with application of cerebral protection at perioperation, intraoperation, and postoperation in our hospital from January 2002 to August 2005. Perioperative carotid Doppler ultrasound and computed tomography angiography (CTA) were applied in 29 patients and carotid angiography applied in only one patient. The key methods of intraoperative cerebral protection included general anaesthesia, selective shunting, monitoring of transcranial Doppler, and careful manipulation. The methods of postoperative cerebral protection included leaving tracheal cannula and brain ice-bag, maintaining normal blood pressure, and applying dehydrant under guidance by monitoring of transcranial Doppler.</p><p><b>RESULTS</b>Among all the 30 patients, shunts were used in 10 patients (33%), and angioplasty by patch was applied in 17 patients (57%). No cranial nerve-associated complications or death was documented.</p><p><b>CONCLUSION</b>Application of cerebral protection at CEA at perioperation, intraoperation, and postoperation can effectively prevent the occurance of cranial nerve-associated complications.</p>

The effect of examination of enzymes in serum to diagnosis of acute mesenteric ischemia in rabbit / 中华外科杂志

<p><b>OBJECTIVE</b>To study the change regulation of enzymes in serum for the diagnosis and treatment of acute mesenteric ischemia by earlier period.</p><p><b>METHODS</b>Thirty-six of rabbits were divided into three groups included from artery, vein and artery with vein by interrupted in mesenteric vessels respectively and there was twelve rabbits in every groups. It was observed that ALT, AST, ALP, gamma-GT, CK, CK-MB, LDH in serum at mesenteric vessels pre-interrupted and post-interrupted 1, 3, 6, 9 h respectively and the bowel color variety was observed at the same time too.</p><p><b>RESULTS</b>After 3 h from post-occluded of mesenteric vessels, among the three groups there was bowel infarction and ALT, AST, ALP, gamma-GT, LDH in serum all to obviously go up.</p><p><b>CONCLUSION</b>It is beneficial to diagnosis of acute mesenteric ischemia at earlier by the examination of enzymes in serum.</p>