Serum anti-beta2-glycoprotein-I and anticardiolipin antibodies during thrombosis in systemic lupus erythematosus patients

PURPOSE: Antibodies to beta2-glycoprotein-I are more strongly associated with clinical antiphospholipid syndrome than are anticardiolipin antibodies. We previously found a decrease in anticardiolipin antibodies at the time of thrombosis in 6 patients with systemic lupus erythematosus (SLE). We therefore sought to determine the prevalence and levels of antibodies to beta2-glycoprotein-I and to cardiolipin before, during, and after thrombosis in patients with SLE, and to compare them with patients who did not have thrombosis. METHODS: We studied 24 patients with SLE who had at least one episode of thrombosis and 102 patients with SLE without thrombosis. Serum anticardiolipin antibodies were measured by conventional enzyme-linked immunosorbent assay (ELISA) using newborn calf serum as the blocking agent. Serum anti-beta2-glycoprotein-I antibodies were measured by ELISA on nonirradiated plates, using purified human beta2-glycoprotein-I without phospholipid. RESULTS: All patients with thrombosis had anti-beta2-glycoprotein-I antibodies, compared with only 17% of controls (P <0.0001). We observed a significant decrease in serum anti-beta2-glycoprotein-I levels at the time of thrombosis, as compared with previous and subsequent samples. The prevalence and levels of IgG and IgM anticardiolipin antibodies were similar in patients with and without thrombosis. A decrease in IgG or IgM anticardiolipin titers occurred during thrombosis in 6 patients. Anticoagulant, corticosteroid, and immunosuppressive treatments did not appear to affect anti-beta2-glycoprotein-I levels at the time of thrombosis. CONCLUSION: Anti-beta2-glycoprotein-I antibodies are strongly associated with thrombosis in patients with SLE. The decrease of anti-beta2-glycoprotein-I levels at the time of thrombosis may indicate a pathogenic role. This antibody may also be a marker of predisposition for thrombosis in these patients.     

Beh?et's Disease Complicated with Thrombosis: A Report of 93 Chinese Cases

To investigate the clinical features of Behçet''s disease (BD) complicated with thrombosis.Medical records of patients with BD at Peking Union Medical College Hospital from 1993 to 2013 were reviewed to identify thrombosis.Of the 766 patients with BD, 93 patients (16 female and 77 male) developed thrombosis. The most common thrombosis was extremity vein thrombosis (86.0%), including deep vein thrombosis (n = 78) and superficial thrombophlebitis (n = 4). The other thrombosis types associated with BD in descending frequency of order were: vena cava thrombosis (30.1%), pulmonary thromboembolism (15.1%), cerebral venous thrombosis (CVT) (12.9%), intracardiac thrombosis (8.6%), Budd–Chiari syndrome (7.5%), and renal vein thrombosis (4.3%), etc. Venous thrombosis is more frequent than arterial thrombosis, and most of patients (94.6%) experienced multiple thrombosis. A male predominance of extremity vein thrombosis and positive pathergy test, and a female predominance of CVT and genital ulcers were noted. All of these patients exhibited active disease during the emergence of thrombotic events. After treating with glucocorticosteroids, immunosuppressants, and/or anticoagulants, the thrombosis resolved in 89 patients. Three patients died from aneurysm rupture, myocardial infarction and Budd–Chiari syndrome, respectively. One patient with septic shock discontinued therapy during follow-up.Thrombosis in BD patients is male predominance, mainly multiple and venous thrombosis is more common. Active disease patients are prone to thrombosis, which suggest the key role of immunosuppressive therapy for the complication.     

Inferior vena cava thrombosis at its hepatic portion (obliterative hepatocavopathy)

The Budd-Chiari syndrome was primarily described as hepatic vein thrombosis within the liver, but it now includes inferior vena cava (IVC) thrombosis and other conditions that cause hepatic vein outflow obstruction. This author and several others maintain that primary hepatic vein thrombosis and primary IVC thrombosis represent two different clinical disorders. Primary thrombosis of the IVC most commonly occurs in its hepatic portion, which seems to be predisposed to thrombosis and has been called membranous obstruction of IVC, because the thrombus organizes into a fibrous and frequently membranous occlusion of the IVC. The hepatic vein orifices are affected to varying degrees, resulting in congestive liver damage. The cause of IVC thrombosis may be a hypercoagulable state such as coagulation factor deficiency and myeloproliferative disorders, but is more often idiopathic. In Nepal, it is endemic with a suspected association with infections. To consider IVC thrombosis and the congestive liver damage as a disease entity, this author proposes the term obliterative hepatocavopathy, separate from hepatic vein thrombosis. Clinically obliterative hepatocavopathy is less severe in its acute phase compared with hepatic vein thrombosis, but it aggravates occlusion of hepatic vein orifices with recurrent thrombosis. Primary hepatic vein thrombosis and obliterative hepatocavopathy display different hemodynamics of the hepatic veins, IVC, and portal vein; dilatation of the subcutaneous veins in the body trunk is more pronounced in obliterative hepatocavopathy because the ascending lumbar vein becomes the major collateral route. Congestive liver cirrhosis develops after a long clinical course that may be complicated by hepatocellular carcinoma.     

Fibrinolysis and the risk of venous and arterial thrombosis

PURPOSE OF REVIEW: The fibrinolytic system is often regarded as just an innocent bystander in the pathogenesis of venous and arterial thrombosis, while (hyper)coagulation as a risk factor has been studied extensively. In this review, we evaluated studies that investigated the association between fibrinolysis and thrombosis. RECENT FINDINGS: There is some evidence for an association between impaired overall fibrinolytic activity and increased risk of venous or arterial thrombosis. Plasminogen levels were found not to be related to thrombosis. Plasma levels of tissue-type plasminogen activator were related to arterial thrombosis in a number of studies but not to venous thrombosis. Thrombin activatable fibrinolysis inhibitor levels appeared to be associated with venous thrombosis. Studies on the association between thrombin activatable fibrinolysis inhibitor or plasminogen activator inhibitor-1 and arterial thrombosis had conflicting results. SUMMARY: Current evidence on an association between fibrinolysis and thrombosis is inconclusive. Although overall assays point to an association, not all individual factors have an association with thrombosis. Most importantly, plasminogen deficiency is not related to thrombosis, which suggests that the fibrinolytic system as a whole is unimportant in the occurrence of thrombosis. Certain components of the fibrinolytic system, however, appear to be involved in processes unrelated to fibrin degradation but related to other processes important in the development of thrombosis.     

Late coronary stent thrombosis: early vs. late stent thrombosis in the stent era.

The incidence of coronary stent thrombosis is < 1%-2% in recent studies, with the highest-risk period considered to be the first 30 days following stent implantation. Recently, stent thrombosis after 30 days has been reported in patients undergoing brachytherapy with stenting. We reviewed the incidence of stent thrombosis causing myocardial infarction in nonbrachytherapy patients at our institution between 1 January 1996 and 30 November 1999. A case control methodology was employed with a 1:3 ratio of stent thrombosis to control patients. Of 1,191 patients undergoing coronary stenting, acute (< 24 hr) plus subacute (1-30 days) stent thrombosis occurred in 0.92% (11 of 1,191 patients). A further 0.76% (9 of 1,191 patients) developed late stent thrombosis after 30 days. There were no clinical or angiographic features at the time of the initial procedure that were associated with stent thrombosis as an entire group compared with control group, but early (acute and subacute) stent thrombosis patients had a smaller final stent minimal lumen diameter and longer stent length compared with patients who had late stent thrombosis or controls. Late stent thrombosis occurs in nonbrachytherapy patients and is almost as frequent as early stent thrombosis. Further studies are required to determine whether longer-term poststent pharmacological treatment may decrease or prevent this complication.     

Thrombosis prophylaxis in hospitalised medical patients: does prophylaxis in all patients make sense?

BACKGROUND: Most studies on thrombosis prophylaxis focus on postoperative venous thrombosis. In medical wards thrombosis prophylaxis is generally restricted to patients who are immobilised. Our primary aim was to investigate the incidence of venous thrombosis in a general internal ward, to assess whether more rigorous prophylaxis would be feasible. METHODS: We investigated the incidence of venous thrombosis in patients hospitalised from 1992 to 1996 and related our findings to literature reports. RESULTS: The incidence of symptomatic venous thrombosis in internal patients during hospitalisation was 39/6332 (0.6%). Among these 39 patients, 24 had a malignancy, whereas 876 out of all 6332 patients had a known malignancy. So, the incidence in this group with cancer was 2.7% compared with 0.3% (15/5456) in the non-cancer group (relative risk for venous thrombosis due to malignancy was 10.0 (95%C.I. 5.3-18.9). CONCLUSION: The incidence of venous thrombosis during hospitalisation in a department of general internal medicine is low and does not justify prophylaxis in all internal patients. Cancer is a strong risk factor for hospital-acquired thrombosis in the medical ward. Further studies may answer the question as to whether thrombosis prophylaxis in this subgroup is feasible.     

Left ventricular thrombosis and cerebrovascular accident in acute myocardial infarction

In a prospective study of 90 consecutive patients with acute myocardial infarction, 15 (28.3%) of 53 patients with an anterior wall infarction developed a left ventricular thrombosis diagnosed by cross sectional echocardiography. Patients received anticoagulants only after a left ventricular thrombosis had been diagnosed. Twenty eight patients had an inferior infarction, but none of these had a left ventricular thrombosis. Five (5.5%) of the 90 patients suffered a cerebrovascular accident, and all had an anterior wall infarction. In four of these five patients a left ventricular thrombosis was confirmed by echocardiography before the cerebrovascular accident. All patients with left ventricular thrombosis had apical akinesis. The incidence of a thrombosis did not differ in patients with a first anterior myocardial infarction and with reinfarctions. Among the 40 patients with a first anterior wall infarction, 12 with a thrombosis had a significantly higher incidence of enlarged heart on chest radiographs and significantly higher serum aspartate aminotransferase enzyme activity than those without. Thus patients with a large anterior wall infarction and with akinesis in the apical region are at high risk of developing a left ventricular thrombosis, which may be a source of peripheral emboli. Left ventricular thrombosis appears to be rare with infarctions in other locations.     

Left ventricular thrombosis and cerebrovascular accident in acute myocardial infarction.

In a prospective study of 90 consecutive patients with acute myocardial infarction, 15 (28.3%) of 53 patients with an anterior wall infarction developed a left ventricular thrombosis diagnosed by cross sectional echocardiography. Patients received anticoagulants only after a left ventricular thrombosis had been diagnosed. Twenty eight patients had an inferior infarction, but none of these had a left ventricular thrombosis. Five (5.5%) of the 90 patients suffered a cerebrovascular accident, and all had an anterior wall infarction. In four of these five patients a left ventricular thrombosis was confirmed by echocardiography before the cerebrovascular accident. All patients with left ventricular thrombosis had apical akinesis. The incidence of a thrombosis did not differ in patients with a first anterior myocardial infarction and with reinfarctions. Among the 40 patients with a first anterior wall infarction, 12 with a thrombosis had a significantly higher incidence of enlarged heart on chest radiographs and significantly higher serum aspartate aminotransferase enzyme activity than those without. Thus patients with a large anterior wall infarction and with akinesis in the apical region are at high risk of developing a left ventricular thrombosis, which may be a source of peripheral emboli. Left ventricular thrombosis appears to be rare with infarctions in other locations.     

Central venous catheter related thrombosis in haematology patients and prediction of risk by screening with Doppler-ultrasound

Patients with a central venous catheter (CVC) who receive intensive chemotherapy or a stem cell transplantation for haematological disease are at risk for developing CVC-related thrombosis. To study the incidence of thrombosis, 105 consecutive patients underwent serial Doppler-ultrasound and we evaluated whether clinically manifest thrombosis could be predicted by screening with Doppler-ultrasound. Patients with subclavian or jugular inserted CVCs were clinically assessed each day for signs and symptoms of thrombosis. Additional Doppler-ultrasound screens were performed weekly by an independent physician in all patients until CVC removal. Doppler-ultrasound recordings were assessed by two blinded observers. In cases of clinically suspected thrombosis, the attending physicians followed routine diagnostic and therapeutic procedures. The overall cumulative incidence of CVC-related thrombosis was 28.6% (30 of 105 patients). Of the 30 patients with thrombosis, 26 had subclinical thrombosis by Doppler-ultrasound, nine of whom developed clinically manifest thrombosis later. Four patients had clinically manifest thrombosis without prior abnormal Doppler-ultrasound. In cases of subclinical thrombosis the risk of developing symptomatic disease increased sevenfold (34.6% vs. 5.1%). Doppler-ultrasound screening may be useful to identify those patients that are at high and low risk for clinically manifest CVC-related thrombosis.     

Factors associating with the presence of residual thrombosis after 3-month treatment of acute pulmonary embolism

The present study aimed to investigate the factors associating with the presence of residual thrombosis in patients with acute pulmonary embolism (APE) after at least 3-month anticoagulant therapy. Demographic and clinical data of 180 cases in the affiliated hospital of Qingdao University from January 2005 to June 2015 were retrospectively analyzed. APE in all patients were confirmed by computed tomography pulmonary angiography (CTPA). Patients were then detected for the presence of residual thrombosis according to a second CTPA. After appropriate comparison test, multivariate logistic regression analysis was performed to identify predictors for residual thrombosis. Among 180 patients, complete clearance of thrombosis occurred in 115 (63.9%) patients. Residual thrombosis remained in 65 (36.1%) patients. The independent factors associating with residual thrombosis include unprovoked APE (OR 0.231, 95% CI 0.062–0.861) and fibrinogen level in acute phase (OR 1.958, 95% CI 1.282–2.911). Furthermore, these two variables were both associated with the presence of residual thrombosis in patients receiving different parenteral anticoagulants (unfractionated heparin or low-molecular-weight heparin). Pulmonary thrombosis in some patients with APE are not completely dissolved after at least 3-month treatment. Additionally, unprovoked APE is positive predictor of decreased residual thrombosis and fibrinogen level in acute phase is a risk factor of the presence of residual thrombosis.     

Thrombosis in multiple myeloma (MM)

Thrombosis is a frequent feature in individuals with myeloma, particularly those treated with oral immunomodulatory drugs (IMID) such as thalidomide or lenalidomide concomitantly with anthracyclines or dexamethasone. Up to a third of these individuals may develop venous thrombosis if not given the benefit of prophylaxis. Interestingly, in contrast to individuals with solid tumors in whom thrombosis is a marker of poor prognosis, thrombosis does not impact overall survival in patients with myeloma. This finding suggests that the mechanisms of thrombosis in hematological neoplasms may differ from solid epithelial tumors and that thrombosis in the former may be driven by therapy and not by a procoagulant phenotype of the neoplastic plasma cells. This may also explain why thrombosis in the context of IMID-based therapy may be prevented by the use of prophylactic aspirin. In this text, we review the pathogenesis of thrombosis in myeloma, its relation to different chemotherapeutic regimens and the use of thrombo-prophylaxis.     

Incidence and risk factors of early venous thrombosis associated with permanent pacemaker leads

INTRODUCTION: Pacemaker lead implantation can cause thrombosis, which can be associated with serious local morbidity and complicated by pulmonary embolism. Few reliable estimates of the incidence of thrombosis have been reported. The contribution of established risk factors to venous thrombosis in patients with implanted pacemaker leads is unknown. METHODS AND RESULTS: One hundred forty-five consecutive patients n = 145) underwent routine clinical and Doppler ultrasound evaluation for thrombosis before and 3, 6, and 12 months after lead implantation. Established risk factors for venous thrombosis were assessed in detail for all patients. Clinical outcome, including clinically manifest thrombosis, pulmonary embolism, associated pacemaker lead infection, complicated reinterventions, and death, was evaluated. Thrombosis was observed in 34 (23%) of 145 patients. Thrombosis did not cause any signs or symptoms in 31 patients but resulted in overt clinical symptoms in 3 patients. The absence of anticoagulant therapy, use of hormone therapy, and a personal history of venous thrombosis were associated with an increased risk of thrombosis. The risk of thrombosis increased in the presence of multiple pacemaker leads compared to a single lead. CONCLUSION: Established risk factors for venous thrombosis and the presence of multiple pacemaker leads contribute substantially to the occurrence of thrombosis associated with permanent pacemaker leads. Risk factor assessment prior to implantation may be useful for identifying patients at risk for thrombotic complications. Preventive management in these patients is warranted.     

PAI-1 gene 4G/5G genotype: A risk factor for thrombosis in vessels of internal organs

Although the common 4G/5G polymorphism in the promoter of the PAI-1 gene was suggested to be a risk factor for some of the thrombotic disorders, its significance in the development of thrombosis is still controversial. This study presents the data on a total of 357 patients with different types of thrombosis and 281 unrelated healthy controls. It was found that the 4G/4G genotype is associated with a higher risk of thrombosis (OR, 1.7; 95% CI, 1.1-2.5). Patients were divided into five distinct groups according to the site of thrombosis. Both 4G/4G and 4G/5G genotypes were associated with a higher risk of thrombosis development in a group of 69 patients with internal organ thrombosis (OR, 6.35; 95% CI, 2.5-16.1 and OR, 4.85; 95% CI, 2.0-12.1, respectively). Interestingly, this association was even stronger in a subgroup of 33 patients with portal vein thrombosis (PVT) and 4G/4G and 4G/5G genotypes conferred more than 10- and 6-fold increases in the risk of developing PVT (95% CI: 2.3-47.1 and 1.4-28.8), respectively. No statistically significant association was found between 4G/4G genotype and the groups of deep vein thrombosis (126 patients), cerebral thrombosis (80 patients), retinal thrombosis (72 patients), and purpura fulminans (16 patients). Factor V Leiden or prothrombin G20210A mutations did not emerge as additional risk factors for thrombosis in any of the groups studied. To conclude, this study suggests that there may be an association between 4G/4G and 4G/5G genotypes and the thrombosis in vessels of internal organs especially in the portal veins.     

Factor V Leiden in central venous catheter-associated thrombosis

Subclavian vein thrombosis is a well-recognized complication following central venous catheter insertion and is associated with significant morbidity. The factor V Leiden mutation is an important risk factor for deep venous thrombosis and pulmonary embolism. Whether this mutation also predisposes patients fitted with a central venous catheter to subclavian vein thrombosis is not known. The occurrence of central venous catheter-associated thrombosis was investigated in 277 consecutive patients receiving an allogeneic bone marrow transplantation. All patients received a tunnelled double or triple catheter positioned in the subclavian vein. Catheter-associated thrombosis was diagnosed on the basis of clinical signs of thrombosis, i.e. swelling and/or redness of the limb or venous engorgement and was confirmed with a colour-flow Doppler ultrasound. Thirteen patients were heterozygous for the factor V Leiden mutation. Seven of these patients had a subclavian vein thrombosis (54%), while this occurred in only 9% of the factor V Leiden-negative patients, corresponding with a relative risk of 7.7 (95% CI 3.3-17.9). Factor V Leiden is attributable for 17.3% of all thrombosis in patients with central venous catheters. The majority of patients with the factor V Leiden mutation with a central venous catheter will develop thrombosis. Patients with a factor V Leiden mutation should receive adequate thrombosis prophylaxis upon catheter introduction and the catheter should be removed immediately after the treatment. Based on this very high risk, we advise testing for factor V Leiden in all bone marrow transplantation patients receiving a central venous catheter.     

In-Hospital Risks and Management of Deep Venous Thrombosis According to Location of the Thrombus

BackgroundWhether deep venous thrombosis involving the pelvic veins or inferior vena cava is associated with higher in-hospital mortality or higher prevalence of in-hospital pulmonary embolism than proximal or distal lower extremity deep venous thrombosis is not known.MethodsThis was a retrospective cohort study based on administrative data from the Nationwide Inpatient Sample, 2016, 2017. Patients hospitalized with a primary diagnosis of deep venous thrombosis at known locations were identified by International Classification of Diseases-10-Clinical Modification codes.ResultsIn-hospital all-cause mortality with deep venous thrombosis involving the inferior vena cava in patients treated only with anticoagulants was 2.2% versus 0.8% with pelvic vein deep venous thrombosis (p<0.0001), 0.7% with proximal deep venous thrombosis (p<0.0001) and 0.2% with distal deep venous thrombosis (p<0.0001). Mortality with anticoagulants was similar with pelvic vein deep venous thrombosis compared with proximal lower extremity deep venous thrombosis, 0.8% versus 0.7% (p=0.39). Lower mortality was shown with pelvic vein deep venous thrombosis treated with thrombolytics than with anticoagulants, 0% versus 0.8% (p<0.0001). In-hospital pulmonary embolism occurred in 11% to 23%, irrespective of the site of deep venous thrombosis.ConclusionPatients with deep venous thrombosis involving the inferior vena cava had higher in-hospital mortality than patients with deep venous thrombosis at other locations. Pelvic vein deep venous thrombosis did not result in higher mortality or more in-hospital pulmonary embolism than proximal lower extremity deep venous thrombosis. The incidence of in-hospital pulmonary embolism was considerable with deep venous thrombosis at all sites.     

Hepatic vein thrombosis in Beh?et's disease

We describe four patients with hepatic vein thrombosis caused by Beh?et's disease and review the 17 previously published cases. In addition, we compared these 21 cases of hepatic vein thrombosis to our 24 cases of hepatic vein thrombosis caused by primary myeloproliferative disorders. In patients with Beh?et's disease, a male predominance (male/female ratio, 19:1) contrasted with the female predominance found in patients with hepatic vein thrombosis complicating primary myeloproliferative disorders (sex ratio = 1:3). The mean age at clinical onset was younger in patients with Beh?et's disease than in those with primary myeloproliferative disorders (29 vs. 35 yr). Obstruction of the inferior vena cava was found in 90% of patients with hepatic vein thrombosis caused by Beh?et's disease. Inferior vena caval thrombosis appears to be the main pathophysiological mechanism of hepatic vein thrombosis in patients with Beh?et's disease. Unlike patients with primary myeloproliferative disorders who often had a progressive course, one third of patients with Beh?et's disease had acute liver failure and died within 2 wk of clinical onset. These findings suggest that, in patients with Beh?et's disease, hepatic vein thrombosis is a sudden event usually related to the extension of a caval thrombus to the ostium of the hepatic veins.     

Inherited and acquired risk factors for venous thromboembolism

Venous thrombosis, or venous thromboembolism, comprises deep vein thrombosis with or without symptomatic pulmonary embolus. The development of symptomatic venous thrombosis is highly dependent on gene-environment interaction. In most instances this interaction results in hypercoagulability (the intermediate phenotype) sufficient to result in intraluminal clot formation (the disease phenotype). The genetic framework underlying venous thrombosis is complex, and there is a large material contribution from disease and interaction with environmental factors. For example, venous thrombosis is related to recent hospitalization in approximately half of all adult cases. After a first episode of venous thrombosis patients are 40 times more likely to suffer a further event compared with previously unaffected individuals. However, the risk differs between patients. Duration of anticoagulation (lifelong or not) should be made with reference to whether an episode of thrombosis was provoked and the presence of other risk factors. The results of testing for heritable thrombophilia rarely influence duration of treatment.     

Risk factors for thrombosis in lupus patients.

Lupus anticoagulant, concentrations of anticardiolipin antibodies, antithrombin III, plasminogen, (free) protein S, protein C, prothrombin, platelet counts, and bleeding times were determined in 74 lupus patients (58 with systemic lupus erythematosus; 16 with lupus-like disease) to establish the presence of risk factors for thrombosis in these patients. Of the variables evaluated, lupus anticoagulant had the strongest association with a history of thrombosis. Both positive anticardiolipin antibody concentrations and the presence of (mild) thrombocytopenia were significantly associated with a history of thrombosis and the presence of lupus anticoagulant. Reduced concentrations of antithrombin III, plasminogen, (free) protein S, and protein C were found in some patients but were not associated with either thrombosis or lupus anticoagulant. Mean concentrations of total protein S were significantly lower in patients with thrombosis than in those without and in patients with lupus anticoagulant than in those without. The antigenic concentration of prothrombin was reduced in 3/74 (4%) lupus patients. These three patients had lupus anticoagulant but no history of thrombosis, which suggests that a low prothrombin concentration protects patients with lupus anticoagulant from the development of thrombosis. A prolonged bleeding time was associated with the presence of lupus anticoagulant but not with a history of thrombosis. Analysis by stepwise logistic regression did not disclose additional risk factors for thrombosis in lupus patients with lupus anticoagulant. Increased antithrombin III concentrations and decreased free protein S concentrations are often found in lupus patients, unrelated to lupus anticoagulant or thrombosis.     

Primary Thrombosis Prophylaxis in Antiphospholipid Antibody–Positive Patients: Where Do We Stand?

Persistently positive antiphospholipid antibodies (aPLs) with thrombosis and/or pregnancy morbidity are the hallmark of the antiphospholipid syndrome. However, aPL-positive patients with no prior history of thrombosis exist. On the basis of a limited number of studies that predominantly included systemic lupus erythematosus patients, aPL-positive patients without previous thrombosis have a 0% to 3.8% annual incident thrombosis risk. Given that every positive aPL test is not clinically significant and every aPL-positive patient does not have the same thrombosis risk, risk stratification (based on aPL profile, age, systemic autoimmune diseases, and traditional cardiovascular disease or venous thrombosis risk factors) is crucial to determine the first thrombosis risk in aPL-positive patients. The optimal primary thrombosis prevention strategy in patients with clinically significant aPL profiles should include 1) regular monitoring and elimination of non-aPL thrombosis risk factors, 2) aggressive management of clinical and subclinical systemic autoimmune disease activity, and 3) patient counseling and education. The protective effect of low-dose aspirin against incident thrombosis in patients with clinically significant aPL profiles is not supported by randomized controlled data; general population cardiovascular disease risk prediction tools and prevention guidelines formulated based on risk–benefit calculations should play a role in the decision whether to recommend low-dose aspirin. The effectiveness of hydroxychloroquine, statins, or their combination remains to be determined by well-designed randomized controlled trials.