Amanda Walborn

Biomarkers of Inflammation, Thrombogenesis, and Collagen Turnover in Patients With Atrial Fibrillation

The purpose of this study was to determine whether there are any differences in the levels of inflammatory, thrombotic, and collagen turnover biomarkers between individuals with atrial fibrillation (AF) and healthy volunteers. Circulating plasma levels of plasminogen activator inhibitor 1 (PAI-1), CD40-ligand (CD40-L), nucleosomes (which are indicators of cell death), C-reactive protein (CRP), procollagen III N-terminal propeptide (PIIINP), procollagen III C-terminal propeptide (PIIICP), procollagen I N-terminal propeptide, tissue plasminogen activator, and von Willebrand factor were analyzed as potential biomarkers of AF. Baseline plasma was collected from patients with AF prior to ablation surgery at Loyola University Medical Center. Individuals with AF had statistically significantly increased levels of PAI-1, CD40-L, and nucleosomes, when compared to the normal population (P < .0001). Additionally, there was a statistically significant increase in the CRP (P = .01), PIIINP (P = .04), and PIIICP (P = .0008) when compared to normal individuals. From this study, it is concluded that the prothrombotic, inflammatory, and collagen turnover biomarkers PAI-1, CD40-L, nucleosomes, CRP, PIIICP, and PIIINP are elevated in AF.

Biomarker Profile of Sepsis-Associated Coagulopathy Using Biochip Assay for Inflammatory Cytokines:

Disseminated intravascular coagulation (DIC) is a major pathophysiological mechanism of sepsis and greatly increases the risk of death in septic patients. Disseminated intravascular coagulation is a complex physiological phenomenon that involves inappropriate activation of coagulation, inflammation, and endothelial processes. The purpose of this study was to analyze the levels of inflammatory cytokines in the plasma of patients with DIC in order to compare the measured levels with those from healthy individuals, draw correlations, and provide a basis for further biomarker panel development. The inflammatory biomarkers interleukin (IL) 1β, IL-6, IL-8, IL-10, interferon (IFN) γ, vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF) α, monocyte chemoattractant protein (MCP)-1, and epidermal growth factor (EGF) showed significant (P < .05) elevation in patients with DIC. Interestingly, while numerous correlations were present between IL-β, IL-6, IL-8, IL-10, IFN-γ, TNF-α, MCP-1, and many of the inflammatory cytokines measured, VEGF and EGF exhibited much less extensive correlation, suggesting that their involvement in DIC may be independent of the other investigated inflammatory markers.

Modulation of Interleukins in Sepsis-Associated Clotting Disorders: Interplay With Hemostatic Derangement.

Interleukins play a central role in the immune system and are involved in a variety of immunological, inflammatory, and infectious disease states including sepsis syndrome. Levels of interleukins may correlate with overall survival and may directly or indirectly affect some of the regulators of coagulation and fibrinolysis, thereby disrupting hemostasis and thrombosis. Our hypothesis is that in sepsis-associated coagulopathies (SACs), interleukins may be upregulated, leading to hemostatic imbalance by generating thrombogenic mediators. We profiled the levels of interleukins IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10 in addition to d-dimer (DD) in patients with SAC and in normal donors. We observed the highest increase in interleukins IL-6 (322-fold), IL-8 (48-fold), IL-10 (72-fold), and DD (18-fold). This suggests that interleukins such as IL-6 and IL-10 have a close association with coagulopathy and fibrinolytic dysregulation in sepsis and can be considered as candidates for potential therapeutic targets in SAC.

Fibrinolytic Deficit and Platelet Activation in Atrial Fibrillation and Their Postablation Modulation

This study aims to examine the effects of atrial fibrillation (AF) on the expression of the cellular mediators plasminogen activator inhibitor 1 (PAI-1) and CD40 ligand (CD40-L). Additionally, the effect of catheter ablation on the levels of the aforementioned biomarkers was also examined. In this prospective study, plasma samples were collected from patients with AF at baseline prior to ablation and at 1 and 3 months postablation. There was a statistically significant increase in CD40-L at baseline in patients with AF compared to control (P = .0034). There was a statistically significant decrease in CD40-L levels postablation at both 1 month (P < .0001) and 3 months (P < .0001) compared to baseline. Baseline levels of PAI-1 were elevated compared to the control group (mean 19.55 ± 2.17 ng/mL vs 4.85 ± 0.41 ng/mL) and a statistically significant decrease in circulating PAI-1 levels 1 month postablation (P = .05) was noted compared to preablation levels. These data suggest that inflammation plays an important role in the pathogenesis of AF and that these cellular mediators are modulated by catheter ablation.

International Normalized Ratio Relevance to the Observed Coagulation Abnormalities in Warfarin Treatment and Disseminated Intravascular Coagulation

The development of coagulation abnormalities is common in patients with sepsis. Sepsis-associated coagulopathy (SAC) is typically diagnosed by prothrombin time (PT) prolongation or elevated international normalized ratio (INR) in conjunction with reduced platelet count. INR is also used to monitor warfarin-treated patients. However, due to the different natures of SAC and warfarin anticoagulation, it is likely that the same INR value provides different information in these two patient populations. The purpose of this study was to compare measures of coagulation function and clotting factor levels in patients with SAC to those observed in patients receiving warfarin anticoagulation. Deidentified plasma samples were collected at baseline from patients diagnosed with SAC and from patients receiving warfarin. These plasma samples were evaluated for PT/INR, activated partial thromboplastin time (aPTT), fibrinogen, and functional and immunologic levels of factors VII, IX, and X. Both aPTT and fibrinogen correlated with INR in patients with SAC, but not in patients treated with warfarin. Factors VII, IX, and X showed an inverse relationship with INR in the anticoagulated patients; however, no relationship between factor level and INR was observed in patients with SAC. Distinct patterns of coagulopathy were observed in patients with SAC and patients receiving warfarin anticoagulation, and equivalent INR values were associated with distinct coagulation profiles in the two patient groups. These results suggest that an abnormal INR provides different information about the coagulation status in patients with disseminated intravascular coagulation than in patients receiving warfarin. This may indicate that an equivalently increased INR predicts different bleeding risks in these two patient groups.

Biomarker Profiling of Neurovascular Diseases in Patients with Stage 5 Chronic Kidney Disease

Patients with stage 5 chronic kidney disease (CKD5D) have a higher risk of developing neurocognitive deficits. Stroke, cervical carotid artery disease (CCAD), and intracranial atherosclerotic disease (ICAD) are causes of such deficits in CKD5D. Chronic inflammation from renal failure elevates risk for these diseases through oxidative stress and vascular dysfunction. The adverse impact on the carotid and intracranial vasculatures contributes to the multifactorial pathophysiology of stroke. Eleven plasma biomarker levels in patients with CKD5D (n = 97) and healthy controls (n = 17-50) were measured using sandwich enzyme-linked immunosorbent assay (ELISA) method. Of the 97 patients with CKD5D, 24 had CCAD, 19 had ICAD, and 23 had acute stroke. Elevations in NACHT, LRR, and PYD domains-containing protein 3 (NALP3) levels in patients with CKD5D (+)CCAD (1.80 ± 0.11 ng/mL) compared to patients with (−)CCAD (1.55 ± 0.08 ng/mL) were statistically significant (P = .0299). Differences in D-dimer levels were also found to be statistically significant (P = .0258) between CKD5D (+)stroke (1.83 ± 0.42 μg/mL) and (−)stroke (0.89 ± 0.13 μg/mL) groups. The ages of the (+) neurovascular disease groups were found to be significantly elevated compared to the (−) neurovascular disease groups (P = .0002 carotid AD; P < .0001 ICAD; P = .0157 stroke). D-dimer levels were positively correlated with age in CKD5D (P = .0375). With the possible exception of NALP3 for CCAD, profiling levels of specific biomarkers for risk stratification of neurovascular diseases in the CKD5D population warrants further investigation.

Angiopoietin 2 Levels in the Risk Stratification and Mortality Outcome Prediction of Sepsis-Associated Coagulopathy

It has been well established that angiopoietin 2 (Ang-2), a glycoprotein involved in activation of the endothelium, plays an integral role in the pathophysiology of sepsis and many other inflammatory conditions. However, the role of Ang-2 in sepsis-associated coagulopathy (SAC) specifically has not been defined. The aim of this study was to measure Ang-2 plasma levels in patients with sepsis and suspected disseminated intravascular coagulation (DIC) in order to demonstrate its predictive value in SAC severity determination and 28-day mortality outcome. Plasma samples were collected from 102 patients with sepsis and suspected DIC at intensive care unit (ICU) admission. The Ang-2 plasma levels were quantified using a sandwich enzyme-linked immunosorbent assay method. The International Society on Thrombosis and Haemostasis DIC scoring system was used to compare the accuracy of Ang-2 levels versus clinical illness severity scores in predicting SAC severity. Mean Ang-2 levels in patients with sepsis and DIC were significantly higher in comparison to healthy controls (P < 0.0001), and median Ang-2 levels showed a downward trend over time (P = 0.0008). Baseline Ang-2 levels and clinical illness severity scores were higher with increasing severity of disease, and Ang-2 was a better predictor of DIC severity than clinical illness scores. This study demonstrates that Ang-2 levels are significantly upregulated in SAC, and this biomarker can be used to risk stratify patients with sepsis into non-overt DIC and overt DIC. Furthermore, the Ang-2 level at ICU admission in a patient with sepsis and suspected DIC may provide a predictive biomarker for mortality outcome.

Postoperative Changes in the Systemic Inflammatory Milieu in Older Surgical Patients

Dysregulated inflammation is a central component of wound healing following surgery. We prospectively enrolled older patients (n = 25, age 65 ± 7 years) undergoing elective total knee arthroplasty or total hip arthroplasty secondary to advanced osteoarthritis (OA) and healthy controls (n = 48). Inflammatory, proangiogenic (vascular endothelial growth factor [VEGF], monocyte chemoattractant protein-1 [MCP-1], and interleukin-8 [IL-8]), and antiangiogenic (interferon γ [IFN-γ] and IL-4) factors were measured using a high-sensitivity biochip. Patients with OA had significantly higher baseline VEGF (10.5 ± 1.2 pg/mL vs 4.8 ± 0.2 pg/mL, P < .001), MCP-1 (130.6 ± 7.7 pg/mL vs 88.6 ± 3.9 pg/mL, P < .0001), and IL-8 (4.0 ± 0.5 pg/mL vs 2.6 ± 0.1 pg/mL, P < .05). Postoperatively, the levels of VEGF (10.5 ± 1.2 pg/mL vs 18.8 ± 1.5 pg/mL, P < .001) and MCP-1 (130.6 ± 7.7 pg/mL vs 153.1 ± 11.5 pg/mL, P < .05) increased significantly. Baseline and postoperative MCP-1 levels correlated positively and significantly with age. The levels of IFN-γ and IL-4 (which has anti-inflammatory properties) did not significantly differ at baseline in patients with OA compared to controls and did not significantly rise postoperatively. We conclude that systemic levels of pro-inflammatory and angiogenic proteins are increased in patients with OA and rise further postoperatively, while proteins that restrain inflammation and angiogenesis do not coordinately rise. These findings implicate imbalance in inflammatory pathways in OA that may contribute to its pathobiology.

Disseminated Intravascular Coagulation: An Update on Pathogenesis, Diagnosis, and Therapeutic Strategies

Disseminated intravascular coagulation (DIC) is an acquired clinicobiological syndrome characterized by widespread activation of coagulation leading to fibrin deposition in the vasculature, organ dysfunction, consumption of clotting factors and platelets, and life-threatening hemorrhage. Disseminated intravascular coagulation is provoked by several underlying disorders (sepsis, cancer, trauma, and pregnancy complicated with eclampsia or other calamities). Treatment of the underlying disease and elimination of the trigger mechanism are the cornerstone therapeutic approaches. Therapeutic strategies specific for DIC aim to control activation of blood coagulation and bleeding risk. The clinical trials using DIC as entry criterion are limited. Large randomized, phase III clinical trials have investigated the efficacy of antithrombin (AT), activated protein C (APC), tissue factor pathway inhibitor (TFPI), and thrombomodulin (TM) in patients with sepsis, but the diagnosis of DIC was not part of the inclusion criteria. Treatment with APC reduced 28-day mortality of patients with severe sepsis, including patients retrospectively assigned to a subgroup with sepsis-associated DIC. Treatment with APC did not have any positive effects in other patient groups. The APC treatment increased the bleeding risk in patients with sepsis, which led to the withdrawal of this drug from the market. Treatment with AT failed to reduce 28-day mortality in patients with severe sepsis, but a retrospective subgroup analysis suggested possible efficacy in patients with DIC. Clinical studies with recombinant TFPI or TM have been carried out showing promising results. The efficacy and safety of other anticoagulants (ie, unfractionated heparin, low-molecular-weight heparin) or transfusion of platelet concentrates or clotting factor concentrates have not been objectively assessed.