Endothelial dysfunction associated with chronic intravascular coagulation in secondary pulmonary hypertension

The Role of the Vascular System in Degenerative Diseases: Mechanisms and Implications

Degenerative diseases, encompassing a wide range of conditions affecting various organ systems, pose significant challenges to global healthcare systems. This comprehensive review explores the intricate interplay between the vascular system and degenerative diseases, shedding light on the underlying mechanisms and profound implications for disease progression and management. The pivotal role of the vascular system in maintaining tissue homeostasis is highlighted, as it serves as the conduit for oxygen, nutrients, and immune cells to vital organs and tissues. Due to the vital role of the vascular system in maintaining homeostasis, its dysfunction, characterized by impaired blood flow, endothelial dysfunction, and vascular inflammation, emerges as a common denominator of degenerative diseases across multiple systems. In the nervous system, we explored the influence of vascular factors on neurodegenerative diseases such as Alzheimer's and Parkinson's, emphasizing the critical role of cerebral blood flow regulation and the blood-brain barrier. Within the kidney system, the intricate relationship between vascular health and chronic kidney disease is scrutinized, unraveling the mechanisms by which hypertension and other vascular factors contribute to renal dysfunction. Throughout this review, we emphasize the clinical significance of understanding vascular involvement in degenerative diseases and potential therapeutic interventions targeting vascular health, highlighting emerging treatments and prevention strategies. In conclusion, a profound appreciation of the role of the vascular system in degenerative diseases is essential for advancing our understanding of degenerative disease pathogenesis and developing innovative approaches for prevention and treatment. This review provides a comprehensive foundation for researchers, clinicians, and policymakers seeking to address the intricate relationship between vascular health and degenerative diseases in pursuit of improved patient outcomes and enhanced public health.

Cardiac Drugs in ACHD Cardiovascular Medicine

Adult congenital heart disease (ACHD) is a growing population that requires life-long care due to advances in pediatric care and surgical or catheter procedures. Despite this, drug therapy in ACHD remains largely empiric due to the lack of clinical data, and formalized guidelines on drug therapy are currently lacking. The aging ACHD population has led to an increase in late cardiovascular complications such as heart failure, arrhythmias, and pulmonary hypertension. Pharmacotherapy, with few exceptions, in ACHD is largely supportive, whereas significant structural abnormalities usually require interventional, surgical, or percutaneous treatment. Recent advances in ACHD have prolonged survival for these patients, but further research is needed to determine the most effective treatment options for these patients. A better understanding of the use of cardiac drugs in ACHD patients could lead to improved treatment outcomes and a better quality of life for these patients. This review aims to provide an overview of the current status of cardiac drugs in ACHD cardiovascular medicine, including the rationale, limited current evidence, and knowledge gaps in this growing area.

Bilateral Acute Renal Infarction Due to Paradoxical Embolism in a Patient with Eisenmenger Syndrome and a Ventricular Septal Defect

A 52-year-old man who was diagnosed with Eisenmenger syndrome due to a muscular-type ventricular septal defect 30 years previously, visited our emergency room after experiencing six hours of severe left flank pain and vomiting. On laboratory examination, azotemia and microscopic haematuria were identified. Contrast-enhanced computed tomography also revealed pulmonary embolism (PE) and bilateral acute renal infarction. The flank pain resolved after heparin was administered for anti-coagulation and aspiration thrombectomy was performed. The patient was discharged on warfarin as anticoagulant therapy. In this case, a paradoxical embolism was considered to have been the cause of PE and bilateral acute renal infarction in a patient with Eisenmenger syndrome.

Thromboembolic complications in adult congenital heart disease: the knowns and the unknowns

Despite impressive improvement in long-term survival, adults with congenital heart disease (CHD) remain exposed to a significant cardiovascular morbidity over lifetime. Thromboembolic events (TE) are a major issue. Specific anatomic groups have been shown a particular high risk of TE, including cyanotic heart disease and Fontan circulation. Many intercurrent clinical factors add a substantial risk such as intracardiac medical devices, atrial arrhythmia, endocarditis, or pregnancy. Nevertheless, what is unknown exceeds what is known, especially regarding the management of this heterogenous patient population. Anticoagulation decision should always be individualized weighing balanced with the alternative risk of hemorrhagic complications. In this review, we aim to synthetize existing literature on TE in adults with CHD, discuss management issues, highlight gaps in knowledge, and intend to suggest high priority research.

Coagulation Profiles of Pulmonary Arterial Hypertension Patients, Assessed by Non-Conventional Hemostatic Tests and Markers of Platelet Activation and Endothelial Dysfunction

Many pathophysiologic processes of pulmonary arterial hypertension (PAH), namely, excess vasoconstriction, vascular remodeling and in situ thrombosis, involve the coagulation cascade, and more specifically, platelets. The aim of this study was to globally assess coagulation processes in PAH, by using non-conventional hemostatic tests, along with markers of platelet activation and endothelial dysfunction. We studied 44 new PAH patients (22 with idiopathic PAH and 22 with connective tissue disease) and 25 healthy controls. The following tests were performed: platelet function analyzer-100 (PFA-100), light transmission aggregometry (LTA), rotational thromboelastometry (ROTEM), endogenous thrombin potential (ETP), serotonin, thromboxane A2 and p-selectin plasma levels, and von Willebrand antigen (VWF:Ag) and activity (VWF:Ac). Our results showed that PAH patients had diminished platelet aggregation, presence of disaggregation, defective initiation of the clotting process and clot propagation, and diminished thrombin formation capacity. Serotonin, thromboxane A2 and p-selectin levels were increased, and VWF:Ag and VWF:Ac decreased in the same population. The results of this study suggest that the platelets of PAH patients are activated and present functional abnormalities. The procoagulant activity, in general, appears to be impaired probably due to a sustained and prolonged activation of the procoagulant processes. Larger observational studies are warranted to confirm these laboratory findings.

Prognostic significance of red cell distribution width and its relation to increased pulmonary pressure and inflammation in acute heart failure

BACKGROUND

Red cell distribution width (RDW) in acute heart failure (AHF) is accepted as a prognostic indicator with unclear pathophysiological ties. The aim of this study was to evaluate the prognostic value of RDW in AHF patients in relation to clinical and echocardiographic data.

METHODS

170 patients with AHF were retrospectively studied. All patients had laboratory testing and an echocardiogram performed within 24 h of admission to the Cardiology Department.

RESULTS

During the mean 193 ± 111 days of follow-up, 33 patients died. More advanced age, high RDW and low peak early diastolic velocity of the lateral mitral annulus (MVe') were independent predictors of all-cause mortality with hazard ratios of: 1.05 (95% CI 1.02-1.09), p < 0.005, 1.40 (95% CI 1.22-1.60), p < 0.001, and 0.77 (95% CI 0.63-0.93), p < 0.007, respectively. In a stepwise multiple linear regression model, RDW was correlated with hemoglobin concentration (standardized b = -0.233, p < 0.001), mean corpuscular volum (standardized b = -0.230, p < 0.001), mean corpuscular hemoglobin concentration (standardized b = -0.207, p < 0.007), the natural logarithm of C-reactive protein (CRP) (standardized b = 0.184, p < 0.004) and tricuspid regurgitation peak gradient (TRPG) values (standardized b = 0.179, p < 0.006), whereas MVe' was correlated with atrial fibrillation (standardized b = 0.269, p < 0.001).

CONCLUSIONS

The present data demonstrates a novel relation between higher levels of RDW and elevated TRPG and high sensitivity CRP values in patients with AHF. These findings suggest that RDW, the most important mortality predictor, is independently associated with elevated pulmonary pressure and systemic inflammation in patients with AHF. Moreover, in AHF patients, more advanced age and decreased MVe' are also independently associated with total mortality risk.

Early low molecular weight heparin for postpartum hemorrhage in women with pre-eclampsia. Is it effective to prevent consumptive coagulopathy?

Background: Postpartum hemorrhage has been one of the most common cause of maternal morbidity and mortality. An association between pre-eclampsia (PE) and postpartum hemorrhage has been shown in previous studies. The aim of this study was to compare some characteristics of postpartum hemorrhage between women with and without PE.Methods: Some characteristics of postpartum hemorrhage were compared between women with (n = 34) and without PE (n = 34). Majority of the cases underwent low molecular heparin administration at postpartum eighth hour, however, in cases who did not give satisfactory responses to blood product transfusions, to block suspected disseminated intravascular coagulation (DIC) secondary to the PE induced vascular injury, low molecular weight heparins were started within 2 h of postpartum hemorrhage. Some characteristics of cases with and without PE and with and without early low molecular weight heparin administration were compared.Results: There were five cases who needed massive transfusions in group with PE, conversely, no case required massive transfusion in group without PE (p < .05), in these five cases prophylactic dose low molecular weight heparin was started within 2 h of postpartum period, these cases determined according to the changes in hematocrit, platelet, and fibrinogen levels with corresponding transfusions. Mean systolic and diastolic blood pressures were significantly higher in PE group. Highest lactate dehydrogenase (LDH) level during follow up was significantly higher in group with PE. Mean numbers of erythrocyte, thrombocyte, and fibrinogen transfusions were significantly higher in PE group. Duration of hospital stay was also significantly higher in group with PE.Conclusions: Postpartum hemorrhage in women with PE may be resistant to blood product transfusions due to DIC and vicious cycle can be blocked by early low molecular weight heparin administration.

Platelet and coagulation disorders in newly diagnosed patients with pulmonary arterial hypertension

There is a complex and not fully elucidated association between pulmonary arterial hypertension (PAH) and coagulation disorders. The goal of this study was to evaluate platelet function, coagulation and fibrinolysis in PAH patients at diagnosis, before PAH-specific treatment initiation. We enrolled 20 healthy controls and 30 PAH patients (20 with connective tissue disease (CTD-PAH) and 10 idiopathic (iPAH)). None of the participants was on any antiplatelet or anticoagulation therapy. Blood samples from PAH patients were collected during the initial right heart catheterization. All subjects were assessed with platelet function analyzer-100 (PFA-100), epinephrine (Epi) and ADP-induced light transmission aggregometry (LTA), thromboelastometry (ROTEM) and endogenous thrombin potential (ETP). Our results showed that Epi and ADP-LTA values were significantly lower in newly diagnosed PAH patients compared to controls. Disaggregation was present in 73% of patients, a characteristic not seen in healthy individuals. In ROTEM assay, CT and CFT measurements were significantly higher and a angle lower compared to controls. ETP testing revealed significantly reduced outcomes in AUC, Cmax and Tmax. When CTD-PAH and iPAH patient groups were compared, iPAH ADP-LTA values were significantly decreased compared to CTD-PAH. In conclusion, newly diagnosed PAH patients presented with decreased platelet aggregation, clot propagation and thrombin generation, along with delayed initiation of the coagulation process. These hemostatic deficits could indicate an "exhaustion" of the coagulation process that could be caused by endothelial dysfunction and chronic activation of the procoagulant pathways. Further studies are warranted to confirm these laboratory findings and assess their potential clinical significance.

Age-Dependent Likelihood of In Situ Thrombosis in Secondary Pulmonary Hypertension

Pulmonary arterial thrombosis (PAT) may complicate the clinical course of pulmonary hypertension associated with congenital heart disease (so-called Eisenmenger syndrome, ES). In this study, variables were sought that could represent risk factors for the occurrence of this complication. Twenty patients aged 11 to 53 (median, 33) years were studied. The presence of PAT (spiral computed tomography angiography) was correlated with age, gender group, PAP, hematocrit, peripheral oxygen saturation (SpO2), and plasma levels of endothelial and coagulation dysfunction markers: von Willebrand factor antigen (vWF: Ag), tissue plasminogen activator (t-PA), and D-dimer (enzyme immunoassay). Patients were classified according to the presence (group 1, N=7), or absence (group 2, N=13) of PAT. Group 1 patients were older (42±8 vs. 27±10 years in group 2, p=0.0051), had lower SpO2 (82±7% vs. 89±6% in group 2, p=0.0462) and increased D-dimer levels (637 vs. 149 ng/mL in group 2, median values, p=0.0235). A trend was observed toward an increase in vWF: Ag (125±29 vs. 103±18 U/dL in group 2, p=0.0789) and t-PA (15.7 vs. 9.4 ng/mL in group 2, median values, p=0.0689). Age was the main variable influencing the occurrence of PAT in multivariate analysis (p=0.0026), with odds ratio of 1.204 per year. The age of 35 years was 86% sensitive and 85% specific for occurrence of PAT. Age correlated positively with t-PA (r=0.57, p=0.0111). Thus, PAT is highly prevalent in ES as an age-dependent event, probably associated with endothelial dysfunction. Prophylactic anticoagulation should be considered before the age of 30 years, in particular in subjects with low SpO2 and increased D-dimer levels.

Plasma biomarkers of pulmonary hypertension identified by Fourier transform infrared spectroscopy and principal component analysis

The main goal of this study was to find specific plasma spectral markers associated with pulmonary arterial hypertension (PAH) induced by monocrotaline injection in rats. FTIR was used to monitor biochemical changes in plasma caused by PAH as compared with the systemic hypertension induced by partial ligation on the left artery and with the control group. Both pathologies, systemic and pulmonary hypertension, induced a unique response in the biochemical content of plasma, mainly related to the composition and secondary structure of plasma proteins. For PAH, β-pleated sheet components of plasma proteins were identified whereas the protein composition in systemic hypertension was dominated by unordered structures. In addition, a higher concentration of tyrosine-rich proteins was found in plasma in PAH than in systemic hypertension. The differences between both pathologies were identified also in terms of lipid composition/metabolism as well as in the content of RNA and glucose, suggesting that lipid peroxidation appears upon pulmonary hypertension development. In summary, this work demonstrates that FTIR spectroscopy supported by principal component analysis (PCA) has the potential to become a fast and non-destructive method for biochemical characterization of plasma that consequently could have a diagnostic significance in pulmonary hypertension.

Inflammatory markers are elevated in Eisenmenger syndrome

Inflammation may be an important contributing factor to the progression of Eisenmenger syndrome (ES). Markers of systemic inflammation in ES have not been systematically studied. Inflammatory markers including high-sensitivity C-reactive protein (hs-CRP), interleukin-2 (IL-2), IL-6, and interferon-γ (IFN-γ) were measured in 42 consecutive ES patients (mean age, 24.3 ± 10.6 years) compared with their levels in 22 healthy control subjects. The patients were followed up for a mean duration of 16.3 ± 13.7 months. The levels of inflammatory markers were correlated with clinical and hemodynamic variables at baseline and the outcomes of death, hospitalization, and worsening World Health Organization (WHO) functional class at follow-up evaluation. Compared with the control subjects, ES patients showed a significant elevation in hs-CRP (2.99 ± 3.5 vs 1.1 ± 0.9 mg/dl; p = 0.002) and IFN-γ (41.3 ± 43.6 vs 10.4 ± 6.9 pg/ml; p < 0.001) levels. The levels of IL-2 and IL-6 also were elevated but did not differ significantly from those in the control subjects. The patients with hs-CRP levels higher than 3 mg/dl were significantly older (28.9 ± 10.6 vs 21.5 ± 9.8 years) and had a significantly shorter 6-min walk distance (421.5 ± 133.2 vs 493.3 ± 74.8 m). The levels of inflammatory markers did not correlate with baseline parameters or clinical outcomes. To conclude, the levels of hs-CRP and IFN-γ are significantly elevated in ES. Elevated hs-CRP in ES was associated with older age and shorter 6-min walk distance, but the levels of inflammatory markers were not predictive of clinical events.

Cutaneous vascular anomalies in the neonatal period

Vascular birthmarks can be difficult to diagnose in the perinatal period due to varied growth characteristics and similar initial appearances. Location and type of birthmark can provide signals that extracutaneous involvement may be a concern. This article provides a baseline framework that can help diagnose, define associations and guide workup and treatment in these neonates.

Pulmonary arterial thrombosis in a patient with an atrial septal defect and eisenmenger syndrome

Pulmonary hypertension is characterized by elevated pulmonary arterial pressure and secondary right ventricular failure. A thromboembolic occlusion of the proximal or distal pulmonary vasculature results in chronic thromboembolic pulmonary hypertension. We report an uncommon case that presented to our hospital with symptoms of dyspnea on exertion over 2 years. The patient had been treated for profound pulmonary thrombosis and right ventricular failure with adequate anticoagulation and sildenafil. Our echocardiography disclosed a large atrial septal defect with severe pulmonary hypertension and right ventricular failure. A diagnosis of Eisenmenger syndrome with pulmonary artery thrombosis was made. Although Eisenmenger syndrome with pulmonary thrombosis is well described in western societies, a huge pulmonary thrombosis is seldom reported in eastern countries. Profound pulmonary thrombosis may obfuscate the actual diagnosis of pulmonary artery hypertension with underlying congenital heart disease. A physical examination and echocardiography are essential in patients with pulmonary hypertension.

Pulmonary thromboembolism in a patient with rheumatic mitral valve stenosis: a fortuitous association?

In this case report, we illustrate our experience with a patient simultaneously suffering from rheumatic mitral valve stenosis and pulmonary thromboembolism who successfully underwent mitral valve replacement and pulmonary thromboendarterectomy. Physical examination and transthoracic echocardiography revealed mitral stenosis, atrial fibrillation, and a large thrombus in the left atrium. The preoperative workup led to the diagnosis of pulmonary thromboembolism. This case emphasizes the importance of preoperative evaluation for pulmonary thromboembolism in symptomatic patients with mitral valve stenosis and atrial fibrillation.

Calibrated automated thrombography demonstrates hypercoagulability in patients with idiopathic pulmonary arterial hypertension

INTRODUCTION

Pathogenesis of idiopathic pulmonary arterial hypertension (iPAH) includes endothelial dysfunction and in situ thrombosis. A hypercoagulable state has also been postulated but never demonstrated. Our objective was to determine whether patients with iPAH had a hypercoagulable state using calibrated automated thrombography (CAT), a new tool to phenotype coagulation in vitro.

PATIENTS AND METHODS

16 patients with iPAH and 29 controls were studied. In vitro platelet dependent coagulation phenotyping by CAT monitored the activity of thrombin generation over time. Plasma levels of soluble thrombomodulin, tissue factor pathway inhibitor (TFPI) and von Willebrand factor (VWF) were measured as endothelial biomarkers.

RESULTS

Endogenous thrombin potential (ETP) in the absence of activated protein C (APC) tended to be increased in patients compared to controls (1769 versus 1656 nM.min; p=0.053). ETP was higher in the presence of APC 25 nM (ETP-APC) in patients (781 versus 494 nM.min; p=0.005). Five patients had ETP-APC higher than the 95th centile of controls. Other CAT parameters (lag time, peak thrombin and time to peak) were all consistent with some degree of hypercoagulability in patients. Regarding endothelial plasma biomarkers sTM was lower (28.4 versus 40.6 μg/l, p=0.0108) in patients; TFPI antigen and activity (respectively: 14.3 versus 10.5 μg/l, p=0.0167; 1.155 versus 1.070, p=0.0021) and VWF (1300 versus 976%, p=0.0108) were higher in patients.

CONCLUSION

We have demonstrated that at least some patients with iPAH have a hypercoagulable phenotype.

Procoagulant membrane microparticles correlate with the severity of pulmonary arterial hypertension

RATIONALE

Procoagulant microparticles constitute valuable hallmarks of cell damage. Microparticles also behave as cellular effectors.

OBJECTIVES

We hypothesized that the extent of the vascular cell damage measured by circulating microparticles could be related to the severity of pulmonary arterial hypertension (PAH).

METHODS

Circulating biomarkers of vascular damage and cell activation were measured in blood samples from 20 patients with PAH. Samples were withdrawn from occluded pulmonary artery and jugular vein. Peripheral venous blood samples were obtained in 23 control subjects. The microparticle procoagulant abilities were quantified by functional prothrombinase and tissue factor assays and their cellular origin was determined.

MEASUREMENTS AND MAIN RESULTS

Soluble vascular cellular adhesion molecule-1 and proinflammatory markers, such as monocyte chemoattractant protein-1 and highly specific C-reactive protein, were elevated in patients with PAH compared with control subjects. Microparticles bearing active tissue factor and CD105 (endoglin) were also elevated in patients with PAH compared with control subjects (29 +/- 13 vs. 16 +/- 6 fmol/L, P < 0.001, and 1.10 +/- 0.46 vs. 0.49 +/- 0.33 nmol/L phosphatidylserine equivalent, P < 0.001, respectively). A further increase in endothelium-derived CD105 microparticles was observed in pulmonary arterial blood compared with venous blood in patients with PAH (1.73 +/- 0.77, P = 0.038). Microparticles bearing active tissue factor were at a higher level in patients in functional class III and IV and who were walking fewer than 380 m with the six-minute-walk test.

CONCLUSIONS

Circulating markers of endothelium damage, proinflammatory markers, and cell stimulation estimated with circulating microparticles appear to be valuable tools in determining the severity of PAH.

Pulmonary hypertension in thalassemia: association with platelet activation and hypercoagulable state

The pathogenesis of pulmonary hypertension (PAH), a serious complication in thalassemia, is not well understood. Thromboembolism has been postulated as one of the causative factors; however, there are currently limited specific data on its role. To examine whether increased platelet activation and hypercoagulability are linked to PAH, 25 beta-thalassemia major and beta-thalassemia intermedia patients were evaluated with Doppler echocardiograms for estimation of pulmonary artery pressure and with laboratory assays for indications of a prothrombotic state. The association of clinical variables and abnormal coagulation assays with PAH was determined. PAH was identified in 17 (68%) patients; mean pulmonary artery systolic pressure was 39.8 +/- 5.4 mm Hg. PAH was significantly associated with prior splenectomy, older age, and evidence for chronic hemolysis, diagnosed in both transfused (n = 10) and nontransfused (n = 7) patients. Increased platelet activation, measured by P-selectin, was significantly associated with PAH (P = 0.001). Increased thrombin-antithrombin III level was more prevalent in the presence of PAH, but increased fibrinolysis or low protein C levels were not. This study underscores the role of platelet activation in the development of PAH and stresses its occurrence even among patients who are regularly transfused, especially those who are older and have had splenectomies.

Eisenmenger syndrome: medical prevention and management strategies

The original definition of Eisenmenger syndrome refers to an unrestrictive post-tricuspid valve congenital systemic-to-pulmonary shunt. When the pulmonary arterial systolic pressure becomes equal to the systemic arterial systolic pressure, the direction of the shunt becomes pulmonary-to-systemic. The latter leads to progressive cyanosis, and exercise intolerance is initially proportional to the degree of hypoxaemia. Later, congestive heart failure may occur . The management principle is to avoid any factors that destabilise this delicately balanced physiology. Until recently, this could only be achieved by symptomatic therapy; however, when patients are severely incapacitated, transplantation is needed. At present, new drugs, which are more selective pulmonary vasodilators, are available to interfere with the ongoing disease process to improve functional capacity and delay the decision for transplantation.

Pulmonary thrombosis in adults with Eisenmenger syndrome

OBJECTIVES

We sought to determine the prevalence of pulmonary artery thrombosis in patients with Eisenmenger syndrome and to identify individuals at highest risk.

BACKGROUND

Eisenmenger syndrome is associated with pulmonary arterial thrombus formation. Both the prevalence and the determinants of pulmonary arterial thrombosis are unknown.

METHODS

This is a review of patients with Eisenmenger syndrome seen at the Toronto Congenital Cardiac Centre for Adults, Canada. Patients underwent a contrast-enhanced computed tomographic (CT) scan of the thorax.

RESULTS

Forty-nine consecutive patients with Eisenmenger syndrome were seen in our hospital. Fifteen patients did not undergo CT angiograms; therefore, 34 patients (mean age 42 +/- 10 years) were included in the study. Responsible shunts included ventricular septal defect (65%), atrial septal defect (15%), patent ductus arteriosus (9%), and other (11%). The prevalence of proximal pulmonary artery thrombus was 21% (7/34) of patients. Evidence of more distal vessel thrombosis was observed in 43% (3/7) of the patients who had visible thrombus in the proximal pulmonary arteries. Patients with thrombus were more likely to be female (86% vs. 37%, p = 0.04) and to have lower oxygen saturations (72% +/- 9% vs. 85% +/- 6%, p = 0.01). Differences in functional status did not identify patients at highest risk for thrombosis.

CONCLUSIONS

Patients with Eisenmenger syndrome have a substantial risk of pulmonary artery thrombus formation. Women and patients with lower oxygen saturations are at the highest risk of developing thrombosis. In the context of an increased bleeding tendency in these patients, the role of anticoagulation treatment needs to be determined.