Newer antiphospholipid antibodies predict adverse outcomes in patients with acute coronary syndrome

Influence of statin therapy on antiphospholipid antibodies and endothelial dysfunction in young patients with coronary artery disease and systemic lupus erythematosus

INTRODUCTION

Antiphospholipid antibodies (aPL) affect atherogenesis and may cause thromboembolism in systemic lupus erythematosus (SLE) and coronary artery disease (CAD). Intensive treatment with statins may reduce inflammation and decrease the number of thrombotic events. That may explain the beneficial effect of statin therapy in SLE and CAD. This study was established to investigate the influence of statin treatment on aPL antibody levels and selected endothelial dysfunction markers in CAD and SLE patients.

MATERIAL AND METHODS

Fifty-eight patients - 40 after coronary revascularization (age 38.9 (27-46), 35 males) and 18 with clinically stable SLE (age 38.8 (18-62), 1 male) - were enrolled in the study. In both groups intensive atorvastatin treatment was administered. At baseline and after 1 year of follow-up serology tests were performed: anticardiolipin antibodies (aCL), anti-β2 glycoprotein I (aβ2GPI), lupus anticoagulant (LA), C-reactive protein (CRP), soluble form of intracellular adhesion molecule-1 (sICAM-1), vWF:Ag.

RESULTS

Coronary artery disease patients in 1 year follow-up revealed a decrease of aβ2GPI IgG and CRP. There was a significant increase in aCL IgG, sICAM-1 and vWF:Ag. In SLE patients aPL levels showed no significant reduction after treatment.

CONCLUSIONS

In clinically stable patients IgM and IgG class aβ2GPI levels are higher in CAD than in SLE, whereas IgG class aCL levels are lower. Statin treatment decreases the CRP level in both SLE and CAD patients, while decreasing the aβ2GPI IgG level only in CAD patients.

Immunoglobulin G (IgG) anticardiolipin antibodies and recurrent cardiovascular events. A systematic review and Bayesian meta-regression analysis

BACKGROUND

Anticardiolipin antibodies of the immunoglobulin G isotype (IgG aCL) have been suggested as risk factor for arterial and venous thrombosis. No conclusive data in patients with coronary artery disease (CAD) do exist. We investigate the risk of recurrent CAD according to the presence of IgG aCL.

METHODS

We performed a systematic review and meta-analysis to evaluate the risk of recurrent major adverse cardiac events (MACE) associated with the presence of IgG aCL in patients with CAD. MEDLINE and Cochrane databases were searched. We conducted a meta-analysis of the relative risk (RR) both at 12 and 24 months.

RESULTS

We included 11 eligible studies with a total of 2425 patients, 283 IgG aCL+ and 2142 IgG aCL-. The prevalence of IgG aCL+ ranged from 6.1% to 43.3%. A total of 341 cardiac events were reported: 71 (25.1%) in IgG aCL+ and 270 (12.6%) in IgG aCL- patients. We found an increased risk of recurrent MACE in patients with high IgG aCL both at 12 (RR 2.17, 2.5-97.5%CI, 1.54-3.00) and 24 months (RR 2.11, 2.5-97.5%CI, 1.62-2.66). This association was even stronger in patients with juvenile CAD (i.e. <50 years) at both 12 (RR 3.21, 2.5-97.5%CI, 1.74-5.41) and 24 months (RR 3.24, 2.5-97.5%CI, 1.84-5.21).

CONCLUSION

Patients with CAD and elevated IgG aCL have a doubled risk of recurrent MACE at 12 and 24 months. The presence of aCL should be suspected in patients with recurrent CAD events or in patients with juvenile CAD.

The frequency of anti-phospholipid antibody syndrome in patients with premature coronary artery disease

Introduction: Coronary Artery Disease (CAD) is known as the major cause of morbidity and mortality in the world with a growing trend, especially in some developing countries. CAD commonly observed in elderly cases, however; recently it is usually found in young adults. In this study, we aimed to evaluate the prevalence of anti-phospholipid antibody syndrome (APS) in patients with premature CAD.

Methods: The cross-sectional study was conducted in Baqiyatallah hospital from April 2012 to April 2016. Patients with premature CAD were included in the study. The data regarding the laboratory tests, echocardiography, and angiography were obtained from all cases.

Results: Overall 133 eligible patients were included in the study. In the first set of the laboratory test, 18 patients were recognized to have APS (13.53%). The second confirmatory APA test was showing 3 of 18 patients were considered to have APS (2.25%).

Conclusion: The results showed there is an association between the risk of developing Premature CAD and APS could potentially. The APS may have significant effects on the risk of coronary heart disease, especially in young adults.

Antiphospholipid syndrome combined with acute coronary syndrome: Case report

RATIONALE

Antiphospholipid syndrome (APS) combined with acute coronary syndrome (ACS) is rarely reported.

PATIENT CONCERNS

One male patient with APS was admitted to our hospital, who had recent unstable angina (UA).

DIAGNOSIS

The preliminary diagnosis of ACS and UA (BraunwaldiB) was then made.

INTERVENTIONS

This patient received secondary preventative therapy for coronary heart disease (CHD) in combination with percutaneous transluminal coronary angioplasty (PTCA) and implantation of NeoVas Bioresorbable Coronary Scaffold.

OUTCOMES

The patient was followed up, without new UA episodes were observed at 6 months, 1 year, and 2 year after surgery, respectively.

LESSONS

It was thus concluded that percutaneous coronary intervention (PCI) is effective for APS patients and NeoVas scaffold implantation is presumed safe.

Oxidized Low-Density Lipoprotein-β2-Glycoprotein I Complex But Not Free Oxidized LDL Is Associated With the Presence and Severity of Coronary Artery Disease

Oxidized low-density lipoprotein (oxLDL) and β2-glycoprotein I (β2GPI) have been identified in human atherosclerotic lesions and when complexed have been implicated as a pro-atherothrombotic antigen. We examined the association of free oxLDL and oxLDL-β2GPI complex in patients with coronary artery disease who underwent elective cardiac catheterization. Serum was collected from patients with suspected coronary artery disease immediately before elective cardiac catheterization who were either treated (n = 385) or not treated (n = 150) with statins and from healthy volunteers (n = 134). OxLDL and oxLDL-β2GPI complex levels were determined by enzyme-linked immunosorbent assay. Disease severity was defined angiographically as none-minimal (<20%), moderate (20% to 75%), and severe (>75%) luminal diameter obstruction of any major coronary vessel. Both oxLDL and oxLDL-β2GPI complex were lower in patients on statins (p <0.001). In statin-naive patients, oxLDL-β2GPI complex, but not free oxLDL, was associated with severe coronary artery disease (p = 0.036). However, no association was observed in patients on statins. LDL4 and triglycerides increased with oxLDL-β2GPI complex quartiles (p = 0.001). OxLDL-β2GPI complex (>0.32 U/ml) was predictive of severe atherosclerosis by receiver-operating characteristic curve analysis in statin-naive patients (area under the curve 0.66, p = 0.002). In conclusion, oxLDL-β2GPI appears more predictive of coronary artery disease severity than oxLDL alone in statin-naive patients.

Impact of Antiphospholipid Syndrome and/or Systemic Lupus Erythematosus on the Long-term Adverse Cardiovascular Outcomes in Patients After Percutaneous Coronary Intervention: A Systematic Review and Meta-analysis

Antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) are 2 rare autoimmune disorders which commonly affect women. Several previous studies showed APS to have been evolved from SLE. Secondary APS often coexists with SLE. One common feature relating these 2 diseases are the antiphospholipid antibodies, which are found in most of the patients with APS and in approximately 30% to 40% of patients with SLE, among which, about 10% develop APS. The leading cause of death in these patients is from cardiovascular disease due to accelerated atherosclerosis, which often progresses more rapidly, compared with the general population. However, the impact of APS and/or SLE on the cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) is controversial. Therefore, to solve this issue, we aim to compare the long-term (≥1 year) adverse cardiovascular outcomes after PCI, in patients with APS and/or SLE, and those without these disorders.Medline and EMBASE databases were searched for studies comparing the long-term adverse cardiovascular outcomes between SLE and non-SLE, APS and non-APS, or SLE + APS and non-SLE + non-APS after PCI. We calculated odd ratios (OR) and 95% confidence intervals (CIs) for these categorical variables, and the pooled analyses were performed with RevMan 5.3.Seven studies consisting of a total of 253,436 patients (568 patients in the experimental group and 252,868 patients in the control group) were included in this meta-analysis. During a follow-up period of ≥1 year, mortality and myocardial Infarction (MI) were significantly higher in the experimental group (OR 2.02, 95% CI 1.63-2.49, P < 0.00001 and OR 1.59, 95% CI 1.23-2.05, P = 0.0004, respectively). Major adverse cardiac events and repeated revascularization were also significantly higher in the SLE/APS group (OR 2.40, 95% CI 1.42-4.03, P = 0.001 and OR 2.59, 95% CI 1.26-5.31, P = 0.01, respectively).Antiphospholipid syndrome and SLE are associated with significantly higher long-term (≥1 year) adverse cardiovascular outcomes after PCI. However, because of the limited number of patients and researches done, and due to a larger percentage of heterogeneity observed among several subgroups, this analysis may not generate a powerful result.

Pathophysiology and Treatments of Oxidative Injury in Ischemic Stroke: Focus on the Phagocytic NADPH Oxidase 2

SIGNIFICANCE

Phagocytes play a key role in promoting the oxidative stress after ischemic stroke occurrence. The phagocytic NADPH oxidase (NOX) 2 is a membrane-bound enzyme complex involved in the antimicrobial respiratory burst and free radical production in these cells.

RECENT ADVANCES

Different oxidants have been shown to induce opposite effects on neuronal homeostasis after a stroke. However, several experimental models support the detrimental effects of NOX activity (especially the phagocytic isoform) on brain recovery after stroke. Therapeutic strategies selectively targeting the neurotoxic ROS and increasing neuroprotective oxidants have recently produced promising results.

CRITICAL ISSUES

NOX2 might promote carotid plaque rupture and stroke occurrence. In addition, NOX2-derived reactive oxygen species (ROS) released by resident and recruited phagocytes enhance cerebral ischemic injury, activating the inflammatory apoptotic pathways. The aim of this review is to update evidence on phagocyte-related oxidative stress, focusing on the role of NOX2 as a potential therapeutic target to reduce ROS-related cerebral injury after stroke.

FUTURE DIRECTIONS

Radical scavenger compounds (such as Ebselen and Edaravone) are under clinical investigation as a therapeutic approach against stroke. On the other hand, NOX inhibition might represent a promising strategy to prevent the stroke-related injury. Although selective NOX inhibitors are not yet available, nonselective compounds (such as apocynin and fasudil) provided encouraging results in preclinical studies. Whereas additional studies are needed to better evaluate this therapeutic potential in human beings, the development of specific NOX inhibitors (such as monoclonal antibodies, small-molecule inhibitors, or aptamers) might further improve brain recovery after stroke.

Circulating anti-β2-glycoprotein I antibodies of peripheral arterial disease patients trigger a genomic overexpression of Toll-like receptor 4 in endothelial cells

OBJECTIVE

Circulating anti-β2-glycoprotein I (ABGPI) antibodies are associated with peripheral arterial disease (PAD) and induce the expression of leukocyte adhesion molecules and proinflammatory cytokines by endothelial cells. Our aim is to study a transcriptional activation pathway of the innate immune system through the cellular signalling cascade triggered by receptors Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) of endothelial cells after the exposure of these cells to seropositive ABGPI human serum obtained from PAD patients.

METHODS

We obtained serum samples from PAD patients and controls without PAD. ABGPI serum titer was detected using indirect immunofluorescence. Our sample was stratified into three groups: group I (PAD and ABGPI titer ≥1:100; n = 15), group II (PAD and ABGPI titer <1:100; n = 15), and control participants (no PAD; n = 15). All serum samples were incubated with human aortic endothelial cell (HAEC) culture. Genomic expression of TLR2 and TLR4 receptors and their shared intracellular signalling molecules, myeloid differentiation primary response gene 88 (MyD88), and interleukin (IL)-1 receptor-associated kinase (1IRAK1), were measured after the exposure of HAECs to each serum.

RESULTS

HAEC genomic expression of TLR4 was higher after the exposure to group I serum than after the exposure to group II serum (log10×10-relative quantification [RQ]: 1.80 ± 0.42 vs 1.37 ± 0.39; P = .01) or control serum (log10×10-RQ: 1.80 ± 0.42 vs 1.09 ± 0.26; P < .01). TLR4 expression was higher in group II than in the control group (log10×10-RQ: 1.37 ± 0.39 vs 1.09 ± 0.26; P = .04). TLR4 expression correlated with MyD88 (r = 0.54; P < .01) and IRAK1 (r = 0.55; P < .01) expression. We recorded a positive correlation between MyD88 and IRAK1 genomic expression (r = 0.58; P < .01).

CONCLUSIONS

Our results suggest that serum from PAD patients with elevated ABGPI antibodies induces a genomic overexpression of TLR4 and its cellular signalling molecules in endothelial cells.

Proatherogenic oxidized low-density lipoprotein/β2-glycoprotein I complexes in arterial and venous disease

OxLDL/β2GPI complexes have been implicated in the initiation and progression of atherosclerosis and associated with disease severity and adverse outcomes. We investigate the significance of anti-oxLDL/β2GPI antibodies and oxLDL/β2GPI complexes in patients with arterial and idiopathic venous disease. A cohort of 61 arterial disease patients, 32 idiopathic venous disease patients, and 53 healthy controls was studied. Because statins influence oxLDL/β2GPI, these complexes were analyzed on subjects not taking statins. Arterial and venous groups expressed higher levels of IgG anti-oxLDL/β2GPI antibodies than controls without any other significant clinical association. OxLDL/β2GPI complexes were significantly elevated in arterial (0.69 U/mL, P = 0.004) and venous disease (0.54 U/mL, P = 0.025) than controls (0.39 U/mL). Among arterial diseases, oxLDL/β2GPI was 0.85 U/mL for carotid artery disease, 0.72 U/mL for peripheral artery disease, and 0.52 U/mL for abdominal aortic aneurysm. There was a significant association with male gender, age, hypertension, and history of thrombosis. Subjects with oxLDL/β2GPI above the median (0.25 U/mL) were more likely to have arterial (OR 4.5, P = 0.004) or venous disease (OR 4.1, P = 0.008). Multivariate regression indicated that males (P = 0.021), high cholesterol (P = 0.011), and carotid disease (P = 0.023) were significant predictors of oxLDL/β2GPI. The coexistence of oxLDL/β2GPI in arterial and venous disease may suggest a common oxidative mechanism that independently predicts carotid artery disease.

Antiphospholipid antibodies predict progression of abdominal aortic aneurysms

Antiphospholipid antibodies (aPLs) frequently occur in autoimmune and cardiovascular diseases and correlate with a worse clinical outcome. In the present study, we evaluated the association between antiphospholipid antibodies (aPLs), markers of inflammation, disease progression and the presence of an intra-aneurysmal thrombus in abdominal aortic aneurysm (AAA) patients.

APLs ELISAs were performed in frozen serum samples of 96 consecutive AAA patients and 48 healthy controls yielding positive test results in 13 patients (13.5%) and 3 controls (6.3%; n.s.). Nine of the 13 aPL-positive AAA patients underwent a second antibody testing >12 weeks apart revealing a positive result in 6 cases. APL-positive patients had increased levels of inflammatory markers compared to aPL-negative patients. Disease progression was defined as an increase of the AAA diameter >0.5 cm/year measured by sonography. Follow-up was performed in 69 patients identifying 41 (59.4%) patients with progressive disease. Performing multipredictor logistic regression analysis adjusting for classical AAA risk factors as confounders, the presence of aPLs at baseline revealed an odds ratio of 9.4 (95% CI 1.0–86.8, p = 0.049) to predict AAA progression. Fifty-five patients underwent a computed tomography in addition to ultrasound assessment indicating intra-aneurysmal thrombus formation in 82.3%. Median thrombus volume was 46.7 cm³ (1.9–377.5). AAA diameter correlated with the size of the intra-aneurysmal thrombus (corr_coeff = 0.721, p<0.001), however neither the presence nor the size of the intra-aneurysmal thrombus were related to the presence of aPLs.

In conclusion, the presence of aPLs is associated with elevated levels of inflammatory markers and is an independent predictor of progressive disease in AAA patients.

Rapidly progressive coronary artery disease as the first manifestation of antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune multisystem disorder characterised by high incidence of arterial and venous thrombosis. Cardiovascular manifestations also include valvular heart disease, ventricular thrombi and higher risk for coronary artery disease (CAD). In this case report, we describe a 61-year-old woman who had no significant risk factors for CAD, and presented with aggressive disease in native and graft vessels that required multiple coronary interventions. The extent of her aggressive CAD could not be explained by her risk factors profile. Therefore autoantibodies screening was carried out and showed a strongly positive anticardiolipin and β2 glycoprotein-I antibody, and hence a diagnosis of antiphospholipid syndrome was made.

Subclinical atherosclerosis in systemic lupus erythematosus and antiphospholipid syndrome: focus on β2GPI-specific T cell response

OBJECTIVE

Systemic Lupus Erythematosus (SLE) and antiphospholipid syndrome (APS) are associated with a high prevalence of atherosclerosis. β2 glycoprotein I (β2GPI) represents a link between autoimmunity and endothelial dysfunction. Recently, β2GPI reactive T cells have been identified; however, their role in atherosclerosis is still under investigation. We evaluated early atherosclerosis in patients with SLE and APS and investigated T cell reactivity to β2GPI and its relationship with atherosclerotic process.

APPROACH AND RESULTS

Fifty SLE, 18 patients with primary APS (PAPS), and 25 healthy controls were enrolled. Demographic and clinical data, including traditional cardiovascular risk factors, were recorded. Monocyte β2GPI and Tissue Factor (TF) expression and peripheral blood mononuclear cell response to β2GPI stimulation were evaluated. Doppler ultrasound was performed to investigate flow-mediated dilatation (FMD) and carotid intima-media thickness (IMT). We detected an increase in mean IMT and a decrease in FMD in patients with SLE versus controls (P<0.05 and P=0.0001, respectively) and a decrease in FMD in patients with PAPS versus controls (P<0.05). Monocyte β2GPI and TF expression was higher in patients with SLE and PAPS than in controls (P=0.006 and P=0.001, respectively); no correlation of monocyte β2GPI and TF with IMT or FMD was detected. β2GPI induced peripheral blood mononuclear cell proliferation in 32% of patients with SLE, 25% of patients with PAPS yet in none of the controls. Proliferative response to β2GPI correlated with a history of arterial thrombosis, thrombocytopenia, and IMT >0.9 mm.

CONCLUSIONS

A significant percentage of patients with SLE and PAPS show a β2GPI-specific T cell reactivity, which is associated with subclinical atherosclerosis.

Auto-antibodies as emergent prognostic markers and possible mediators of ischemic cardiovascular diseases

During the last 15 years, a growing body of evidence supported the fact that auto-antibodies represent not only emergent markers but also active mediators of cardiovascular disease (CVD), clinically represented mostly by acute coronary syndrome (ACS) and stroke. There is a contrasted relationship between auto-antibodies and CVD, some being protective, while others acting as potential risk factors. Therefore, we performed a review of the literature on the respective cardiovascular prognostic value of the most relevant auto-antibodies in ACS and stroke, and their putative pathophysiological properties in atherogenesis. This review highlights auto-antibodies as active modulators of the innate immune system in atherogenesis (either toward a pro- or anti-inflammatory response), or by affecting basal heart rate regulation (anti-apoA-1 IgG). Given their apparent prognostic independency towards traditional cardiovascular risk factors, the data available in the literature indicates that some of those auto-antibodies could be of valuable help for cardiovascular risk stratification in the future, especially because their deleterious effects have been shown to be potentially abrogated in vivo and in vitro by existing therapeutic modalities. Although evidence in humans is currently lacking, these studies may open innovative therapeutic perspectives for CVD in the future.

Hughes syndrome (the antiphospholipid syndrome): a disease of our time

A pro-thrombotic condition was described in 1983 which was characterised by the presence of circulating antiphospholipid antibodies, as well as peripheral thrombosis (e.g. DVT), a tendency to internal organ involvement, repeated miscarriage, and, occasionally, thrombocytopenia (aPL) (Hughes, Br Med J 287:1088-1089, 1983). Previously, there had been a number of observations, mainly in patients with lupus having "false positive" tests for syphilis, miscarriage and circulating lupus anticoagulants. The description in 1983 had three notable features (a) a detailed comprehensive clinical picture of the syndrome; (b) this description differed from other coagulopathies in showing a propensity for arterial thrombosis (e.g. stroke and heart attack); and (c) this was a syndrome quite independent from lupus. There are indications that the primary antiphospholipid syndrome will turn out to be more common than lupus, though this could still be a reflection of referral practice.

Antiphospholipid syndrome (Hughes syndrome): 10 clinical topics

This year in Galveston, Texas, Silvia Pierangeli hosts the 13th International Congress on Antiphospholipid Antibodies. Twenty-six years after the first antiphospholipid syndrome meeting, the number of interested colleagues has multiplied, and the subject has become more scientifically understood. So also has the clinical picture. In this short contribution, I will highlight a number of clinical observations which may, or may not, contribute to our understanding of antiphospholipid syndrome.

Oxidized-LDL/beta(2)-glycoprotein I complexes are associated with disease severity and increased risk for adverse outcomes in patients with acute coronary syndromes

Oxidized low-density lipoprotein (oxLDL)/beta(2)-glycoprotein I (beta2GPI) complexes have been implicated in atherogenesis. oxLDL/beta2GPI complexes were measured in 339 patients with suspected acute coronary syndromes. Approximately 68% had angiographically documented coronary artery disease (CAD) and significantly higher mean + or - SD levels of oxLDL/beta2GPI (3.75 + or - 6.31 U/mL) than patients with normal coronary arteries (2.21 + or - 3.03 U/mL; P = .0026). Patients with severe CAD had significantly higher mean + or - SD levels of oxLDL/beta2GPI (8.71 + or - 12.87 U/mL) compared with the overall mean of 3.25 U/mL (P < .05) and a significantly higher rate (28.9%) of adverse events than the overall rate of 11.2% (P < .05). Patients with adverse events had higher mean + or - SD levels of oxLDL/beta2GPI (4.05 + or - 5.38 U/mL) than patients without adverse events (3.15 + or - 5.53; P = .029). The relative risk for adverse events in higher oxLDL/beta2GPI quartiles was 3.1 (95% confidence interval, 1.0-9.1; P = .06) for quartile 3 and 3.5 (95% confidence interval, 1.2-10.4; P = .02) for quartile 4. Our results support the concept that oxLDL/beta2GPI complexes are associated with severity of CAD and a 3.5-fold increased risk for adverse outcomes.

Pathophysiology of β2-glycoprotein I in antiphospholipid syndrome

Since β2-glycoprotein I (β2GPI) was described as the major antigenic target for antiphospholipid antibodies, many studies have focused their attention to the physiological role of β2GPI and anti-β2GPI antibodies on autoimmune-mediated thrombosis. Studies reporting the physiological role of β2GPI have been numerous, but the exact mechanism of action(s) has yet to be completely determined. β2GPI’s epitopes for anti-β2GPI autoantibodies have been characterized, however, not all of the heterogeneous anti-β2GPI antibodies are pathogenic. The pathophysiologic role of β2GPI has been reported in the fields of coagulation, fibrinolysis, angiogenesis, and atherosclerosis. Our understanding of the impact of β2GPI, its metabolites and autoantibodies to β2GPI on these physiological functions may contribute to the development of better therapeutic strategies to treat and prevent autoimmune-mediated atherothrombotic vascular disease. Lupus (2010) 19, 379—384.