Lipid lowering for prevention of venous thromboembolism: a network meta-analysis.

BACKGROUND AND AIMS: Studies have suggested that statins may be associated with reduced risk of venous thromboembolism (VTE). The aim of the current study was to assess the evidence regarding the comparative effect of all lipid-lowering therapies (LLT) in primary VTE prevention. METHODS: After a systematic search of PubMed, CENTRAL, and Web of Science up until 2 November 2022, randomized controlled trials (RCT) of statins (high- or low-/moderate-intensity), ezetimibe, or proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) were selected. An additive component network meta-analysis to compare VTE risk during long-term follow-up across different combinations of LLT was performed. RESULTS: Forty-five RCTs (n = 254 933 patients) were identified, reporting a total of 2084 VTE events. Compared with placebo, the combination of PCSK9i with high-intensity statin was associated with the largest reduction in VTE risk (risk ratio [RR] 0.59; 95% confidence interval [CI] 0.43-0.80), while there was a trend towards reduction for high-intensity (0.84; 0.70-1.02) and low-/moderate-intensity (0.89; 0.79-1.00) statin monotherapy. Ezetimibe monotherapy did not affect the VTE risk (1.04; 0.83-1.30). There was a gradual increase in the summary effect of VTE reduction with increasing intensity of the LLT. When compared with low-/moderate-intensity statin monotherapy, the combination of PCSK9i and high-intensity statin was significantly more likely to reduce VTE risk (0.66; 0.49-0.89). CONCLUSIONS: The present meta-analysis of RCTs suggests that LLT may have a potential for VTE prevention, particularly in high-intensity dosing and in combination therapy.

Optimisation of detecting chronic thromboembolic pulmonary hypertension in acute pulmonary embolism survivors: the InShape IV study.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is often diagnosed late in acute pulmonary embolism (PE) survivors: more efficient testing to expedite diagnosis may considerably improve patient outcomes. The InShape II algorithm safely rules out CTEPH (failure rate 0.29%) while requiring echocardiography in only 19% of patients but may be improved by adding detailed reading of the computed tomography pulmonary angiography (CTPA) diagnosing the index PE. METHODS: Twelve new algorithms, incorporating the CTEPH prediction score, ECG reading, NT-proBNP levels and dedicated CTPA reading were evaluated in the international InShape II (n=341) and part of the German FOCUS cohort (n=171). Evaluation criteria included failure rate, defined as the incidence of confirmed CTEPH in PE patients in whom echocardiography was deemed unnecessary by the algorithm, and the overall net reclassification index (NRI) compared to the InShape II algorithm. RESULTS: The algorithm starting with CTPA reading of the index PE for 6 signs of CTEPH, followed by the ECG/NTproBNP assessment and echocardiography resulted in the most beneficial change compared to InShape II with a need for echocardiography in 20% (+5%), a failure rate of 0%, and an NRI of +3.5, reflecting improved performance over the InShape II algorithm. In the FOCUS cohort, this approach lowered echocardiography need to 24% (-6%) and missed no CTEPH cases, with an NRI of +6.0. CONCLUSION: Dedicated CTPA reading of the index PE improved the performance of the InShape II algorithm and may improve the selection of PE survivors who require echocardiography to rule out CTEPH.

Extracorporeal Membrane Oxygenation and Reperfusion Strategies in High-Risk Pulmonary Embolism Hospitalizations.

OBJECTIVES: To investigate the contemporary use of extracorporeal membrane oxygenation (ECMO) in conjunction with reperfusion strategies in high-risk pulmonary embolism (PE). DESIGN: Observational epidemiological analysis. SETTING: The U.S. Nationwide Inpatient Sample (NIS) (years 2016-2020). PATIENTS: High-risk PE hospitalizations. MEASUREMENTS AND MAIN RESULTS: Use of ECMO in conjunction with thrombolysis-based reperfusion (systemic thrombolysis or catheter-directed thrombolysis) or mechanical reperfusion (surgical embolectomy or catheter-based thrombectomy) with regards to in-hospital mortality and major bleeding. We identified high-risk PE hospitalizations in the NIS (years 2016-2020) and investigated the use of ECMO in conjunction with thrombolysis-based (systemic thrombolysis or catheter-directed thrombolysis) and mechanical (surgical embolectomy or catheter-based thrombectomy) reperfusion strategies with regards to in-hospital mortality and major bleeding. Among 122,735 hospitalizations for high-risk PE, ECMO was used in 2,805 (2.3%); stand-alone in 1.4%, thrombolysis-based reperfusion in 0.4%, and mechanical reperfusion in 0.5%. Compared with neither reperfusion nor ECMO, ECMO plus thrombolysis-based reperfusion was associated with reduced in-hospital mortality (adjusted odds ratio [aOR] 0.61; 95% CI, 0.38-0.98), whereas no difference was found with ECMO plus mechanical reperfusion (aOR 1.03; 95% CI, 0.67-1.60), and ECMO stand-alone was associated with increased in-hospital mortality (aOR 1.60; 95% CI, 1.22-2.10). In the cardiac arrest subgroup, ECMO was associated with reduced in-hospital mortality (aOR 0.71; 95% CI, 0.53-0.93). Among all patients on ECMO, thrombolysis-based reperfusion was significantly associated (aOR 0.55; 95% CI, 0.33-0.91), and mechanical reperfusion showed a trend (aOR 0.75; 95% CI, 0.47-1.19) toward reduced in-hospital mortality compared with no reperfusion, without increases in major bleeding. CONCLUSIONS: In patients with high-risk PE and refractory hemodynamic instability, ECMO may be a valuable supportive treatment in conjunction with reperfusion treatment but not as a stand-alone treatment especially for patients suffering from cardiac arrest.

Fibrinolytic Agents in Thromboembolic Diseases: Historical Perspectives and Approved Indications.

Fibrinolytic agents catalyze the conversion of the inactive proenzyme plasminogen into the active protease plasmin, degrading fibrin within the thrombus and recanalizing occluded vessels. The history of these medications dates to the discovery of the first fibrinolytic compound, streptokinase, from bacterial cultures in 1933. Over time, researchers identified two other plasminogen activators in human samples, namely urokinase and tissue plasminogen activator (tPA). Subsequently, tPA was cloned using recombinant DNA methods to produce alteplase. Several additional derivatives of tPA, such as tenecteplase and reteplase, were developed to extend the plasma half-life of tPA. Over the past decades, fibrinolytic medications have been widely used to manage patients with venous and arterial thromboembolic events. Currently, alteplase is approved by the U.S. Food and Drug Administration (FDA) for use in patients with pulmonary embolism with hemodynamic compromise, ST-segment elevation myocardial infarction (STEMI), acute ischemic stroke, and central venous access device occlusion. Reteplase and tenecteplase have also received FDA approval for treating patients with STEMI. This review provides an overview of the historical background related to fibrinolytic agents and briefly summarizes their approved indications across various thromboembolic diseases.

Cardiopulmonary exercise testing during follow-up after acute pulmonary embolism.

BACKGROUND: Cardiopulmonary exercise testing (CPET) may provide prognostically valuable information during follow-up after pulmonary embolism (PE). Our objective was to investigate the association of patterns and degree of exercise limitation, as assessed by CPET, with clinical, echocardiographic and laboratory abnormalities and quality of life (QoL) after PE. METHODS: In a prospective cohort study of unselected consecutive all-comers with PE, survivors of the index acute event underwent 3- and 12-month follow-ups, including CPET. We defined cardiopulmonary limitation as ventilatory inefficiency or insufficient cardiocirculatory reserve. Deconditioning was defined as peak O2 uptake (V'O2 ) <80% with no other abnormality. RESULTS: Overall, 396 patients were included. At 3 months, prevalence of cardiopulmonary limitation and deconditioning was 50.1% (34.7% mild/moderate; 15.4% severe) and 12.1%, respectively; at 12 months, it was 44.8% (29.1% mild/moderate; 15.7% severe) and 14.9%, respectively. Cardiopulmonary limitation and its severity were associated with age (OR per decade 2.05, 95% CI 1.65-2.55), history of chronic lung disease (OR 2.72, 95% CI 1.06-6.97), smoking (OR 5.87, 95% CI 2.44-14.15) and intermediate- or high-risk acute PE (OR 4.36, 95% CI 1.92-9.94). Severe cardiopulmonary limitation at 3 months was associated with the prospectively defined, combined clinical-haemodynamic end-point of "post-PE impairment" (OR 6.40, 95% CI 2.35-18.45) and with poor disease-specific and generic health-related QoL. CONCLUSIONS: Abnormal exercise capacity of cardiopulmonary origin is frequent after PE, being associated with clinical and haemodynamic impairment as well as long-term QoL reduction. CPET can be considered for selected patients with persisting symptoms after acute PE to identify candidates for closer follow-up and possible therapeutic interventions.

Protein expression profiling suggests relevance of noncanonical pathways in isolated pulmonary embolism.

Patients with isolated pulmonary embolism (PE) have a distinct clinical profile from those with deep vein thrombosis (DVT)-associated PE, with more pulmonary conditions and atherosclerosis. These findings suggest a distinct molecular pathophysiology and the potential involvement of alternative pathways in isolated PE. To test this hypothesis, data from 532 individuals from the Genotyping and Molecular Phenotyping of Venous ThromboEmbolism Project, a multicenter prospective cohort study with extensive biobanking, were analyzed. Targeted, high-throughput proteomics, machine learning, and bioinformatic methods were applied to contrast the acute-phase plasma proteomes of isolated PE patients (n = 96) against those of patients with DVT-associated PE (n = 276) or isolated DVT (n = 160). This resulted in the identification of shared molecular processes between PE phenotypes, as well as an isolated PE-specific protein signature. Shared processes included upregulation of inflammation, response to oxidative stress, and the loss of pulmonary surfactant. The isolated PE-specific signature consisted of 5 proteins: interferon-γ, glial cell line-derived neurotrophic growth factor, polypeptide N-acetylgalactosaminyltransferase 3, peptidyl arginine deiminase type-2, and interleukin-15 receptor subunit α. These proteins were orthogonally validated using cis protein quantitative trait loci. External replication in an independent population-based cohort (n = 5778) further validated the proteomic results and showed that they were prognostic for incident primary isolated PE in individuals without history of VTE (median time to event: 2.9 years; interquartile range: 1.6-4.2 years), supporting their possible involvement in the early pathogenesis. This study has identified molecular overlaps and differences between VTE phenotypes. In particular, the results implicate noncanonical pathways more commonly associated with respiratory and atherosclerotic disease in the acute pathophysiology of isolated PE.

Risk of venous thromboembolic events after COVID-19 infection: a systematic review and meta-analysis.

Data regarding the occurrence of venous thromboembolic events (VTE), including acute pulmonary embolism (PE) and deep vein thrombosis (DVT) in recovered COVID-19 patients are scant. We performed a systematic review and meta-analysis to assess the risk of acute PE and DVT in COVID-19 recovered subject. Following the PRIMSA guidelines, we searched Medline and Scopus to locate all articles published up to September 1st, 2022, reporting the risk of acute PE and/or DVT in patients recovered from COVID-19 infection compared to non-infected patients who developed VTE over the same follow-up period. PE and DVT risk were evaluated using the Mantel-Haenszel random effects models with Hazard ratio (HR) as the effect measure with 95% confidence interval (CI) while heterogeneity was assessed using Higgins I2 statistic. Overall, 29.078.950 patients (mean age 50.2 years, 63.9% males), of which 2.060.496 had COVID-19 infection, were included. Over a mean follow-up of 8.5 months, the cumulative incidence of PE and DVT in COVID-19 recovered patients were 1.2% (95% CI:0.9-1.4, I2: 99.8%) and 2.3% (95% CI:1.7-3.0, I2: 99.7%), respectively. Recovered COVID-19 patients presented a higher risk of incident PE (HR: 3.16, 95% CI: 2.63-3.79, I2 = 90.1%) and DVT (HR: 2.55, 95% CI: 2.09-3.11, I2: 92.6%) compared to non-infected patients from the general population over the same follow-up period. Meta-regression showed a higher risk of PE and DVT with age and with female gender, and lower risk with longer follow-up. Recovered COVID-19 patients have a higher risk of VTE events, which increase with aging and among females.

Towards personalized antithrombotic management with drugs and devices across the cardiovascular spectrum.

Intravascular thrombus formation and embolization are among the most frequent events leading to a number of cardiovascular conditions with high morbidity and mortality. The underlying causes are stasis of the circulating blood, genetic and acquired coagulation disorders, and reduced antithrombotic or prothrombotic properties of the vascular wall (Virchow's triad). In the venous system, intravascular thrombi can cause venous thrombosis and pulmonary and even peripheral embolism including ischaemic stroke [through a patent foramen ovale (PFO)]. Thrombi in the left atrium and its appendage or ventricle form in the context of atrial fibrillation and infarction, respectively. Furthermore, thrombi can form on native or prosthetic aortic valves, within the aorta (in particular at sites of ulcers, aortic dissection, and abdominal aneurysms), and in cerebral and peripheral arteries causing stroke and critical limb ischaemia, respectively. Finally, thrombotic occlusion may occur in arteries supplying vital organs such the heart, brain, kidney, and extremities. Thrombus formation and embolization can be managed with anticoagulants and devices depending on where they form and embolize and on patient characteristics. Vitamin K antagonists are preferred in patients with mechanical valves, while novel oral anticoagulants are first choice in most other cardiovascular conditions, in particular venous thromboembolism and atrial fibrillation. As anticoagulants are associated with a risk of bleeding, devices such as occluders of a PFO or the left atrial appendage are preferred in patients with an increased bleeding risk. Platelet inhibitors such as aspirin and/or P2Y12 antagonists are preferred in the secondary prevention of coronary artery disease, stroke, and peripheral artery disease either alone or in combination depending on the clinical condition. A differential and personalized use of anticoagulants, platelet inhibitors, and devices is recommended and reviewed in this article.

Chronic thromboembolic pulmonary hypertension and impairment after pulmonary embolism: the FOCUS study.

AIMS: To systematically assess late outcomes of acute pulmonary embolism (PE) and to investigate the clinical implications of post-PE impairment (PPEI) fulfilling prospectively defined criteria. METHODS AND RESULTS: A prospective multicentre observational cohort study was conducted in 17 large-volume centres across Germany. Adult consecutive patients with confirmed acute symptomatic PE were followed with a standardized assessment plan and pre-defined visits at 3, 12, and 24 months. The co-primary outcomes were (i) diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH), and (ii) PPEI, a combination of persistent or worsening clinical, functional, biochemical, and imaging parameters during follow-up. A total of 1017 patients (45% women, median age 64 years) were included in the primary analysis. They were followed for a median duration of 732 days after PE diagnosis. The CTEPH was diagnosed in 16 (1.6%) patients, after a median of 129 days; the estimated 2-year cumulative incidence was 2.3% (1.2-4.4%). Overall, 880 patients were evaluable for PPEI; the 2-year cumulative incidence was 16.0% (95% confidence interval 12.8-20.8%). The PPEI helped to identify 15 of the 16 patients diagnosed with CTEPH during follow-up (hazard ratio for CTEPH vs. no CTEPH 393; 95% confidence interval 73-2119). Patients with PPEI had a higher risk of re-hospitalization and death as well as worse quality of life compared with those without PPEI. CONCLUSION: In this prospective study, the cumulative 2-year incidence of CTEPH was 2.3%, but PPEI diagnosed by standardized criteria was frequent. Our findings support systematic follow-up of patients after acute PE and may help to optimize guideline recommendations and algorithms for post-PE care.

Common laboratory tests and their correlation with the clinical presentation and prognosis of Lemierre syndrome.

INTRODUCTION: Lemierre syndrome is a thromboembolic complication following an acute bacterial infection of the head/neck area, often due to anaerobes. Data on the prognostic role of laboratory parameters is lacking. METHODS: We analyzed individual-patient level data from a multinational cohort of patients with Lemierre-syndrome. Patients had an infection in the head/neck area, and contiguous vein thrombosis or septic embolism, irrespective of the causal pathogen. We studied the patterns of white blood cell count, platelet count, and C-reactive protein concentration investigating their association with baseline characteristics and in-hospital clinical outcomes (septic embolism, major bleeding, all-cause death). RESULTS: A total of 447 (63%) patients had complete data for analysis. White blood cells were elevated across all subgroups (median 17 × 103/µL; Q1-Q3:12-21). Median platelet count was 61 × 103/µL (Q1-Q3:30-108) with decreasing levels with increasing age. Males, patients with renal failure or cardiopulmonary impairment, and those with typical Lemierre syndrome (tonsillitis, septic thromboembolism, positivity for Fusobacterium spp.) had the lowest platelet count. Median C-reactive protein was 122 (Q1-Q3:27-248) mg/L with higher values in patients who also had more severe thrombocytopenia. The overall risk of complications was similar across subgroups of patients stratified according to white blood cell and C-reactive protein levels. Patients in the lowest third of platelet count (<42 × 103/µL) had the highest rate of complications (26%), as opposed to those in the highest third (11%), notably septic embolic events. CONCLUSIONS: Common laboratory tests correlate with the clinical presentation of Lemierre syndrome. However, extreme values did not appear to be prognostically relevant for in-hospital complications and potentially able to improve clinical management.

From acute pulmonary embolism to post-pulmonary embolism sequelae.

Aim of this narrative review is to summarize the functional and hemodynamic implications of acute PE and PE sequelae, namely the post-PE syndrome. Briefly, we will first describe the epidemiology, diagnostic procedures, and therapeutic approaches of acute PE. Then, we will provide a definition of the post-PE syndrome and present the so far accumulated evidence regarding its epidemiology and the implications that arise for further diagnosis and treatment. Lastly, we will explore the most devastating long-term complication of PE, namely chronic thromboembolic pulmonary hypertension (CTEPH), and recent advances in its management.

Ultrasound-facilitated, catheter-directed thrombolysis vs anticoagulation alone for acute intermediate-high-risk pulmonary embolism: Rationale and design of the HI-PEITHO study.

BACKGROUND: Due to the bleeding risk of full-dose systemic thrombolysis and the lack of major trials focusing on the clinical benefits of catheter-directed treatment, heparin antiocoagulation remains the standard of care for patients with intermediate-high-risk pulmonary embolism (PE). METHODS AND RESULTS: The Higher-Risk Pulmonary Embolism Thrombolysis (HI-PEITHO) study (ClinicalTrials.gov Identifier: NCT04790370) is a multinational multicenter randomized controlled parallel-group comparison trial. Patients with: (1) confirmed acute PE; (2) evidence of right ventricular (RV) dysfunction on imaging; (3) a positive cardiac troponin test; and (4) clinical criteria indicating an elevated risk of early death or imminent hemodynamic collapse, will be randomized 1:1 to treatment with a standardized protocol of ultrasound-facilitated catheter-directed thrombolysis plus anticoagulation, vs anticoagulation alone. The primary outcome is a composite of PE-related mortality, cardiorespiratory decompensation or collapse, or non-fatal symptomatic and objectively confirmed PE recurrence, within 7 days of randomization. Further assessments cover, apart from bleeding complications, a broad spectrum of functional and patient-reported outcomes including quality of life indicators, functional status and the utilization of health care resources over a 12-month follow-up period. The trial plans to include 406 patients, but the adaptive design permits a sample size increase depending on the results of the predefined interim analysis. As of May 11, 2022, 27 subjects have been enrolled. The trial is funded by Boston Scientific Corporation and through collaborative research agreements with University of Mainz and The PERT Consortium. CONCLUSIONS: Regardless of the outcome, HI-PEITHO will establish the first-line treatment in intermediate-high risk PE patients with imminent hemodynamic collapse. The trial is expected to inform international guidelines and set the standard for evaluation of catheter-directed reperfusion options in the future.

Role of angiopoietin-2 in venous thrombus resolution and chronic thromboembolic disease.

BACKGROUND: Defective angiogenesis, incomplete thrombus revascularisation and fibrosis are considered critical pathomechanisms of chronic thromboembolic pulmonary hypertension (CTEPH) after pulmonary embolism. Angiopoietin-2 (ANGPT2) has been shown to regulate angiogenesis, but its importance for thrombus resolution and remodelling is unknown. METHODS: ANGPT2 plasma concentrations were measured in patients with CTEPH (n=68) and acute pulmonary embolism (n=84). Tissue removed during pulmonary endarterectomy (PEA) for CTEPH was analysed (immuno)histologically. A mouse model of inferior vena cava ligation was used to study the kinetics of venous thrombus resolution in wild-type mice receiving recombinant ANGPT2 via osmotic pumps, and in transgenic mice overexpressing ANGPT2 in endothelial cells. RESULTS: Circulating ANGPT2 levels were higher in CTEPH patients compared to patients with idiopathic pulmonary arterial hypertension and healthy controls, and decreased after PEA. Plasma ANGPT2 levels were elevated in patients with pulmonary embolism and diagnosis of CTEPH during follow-up. Histological analysis of PEA specimens confirmed increased ANGPT2 expression, and low levels of phosphorylated TIE2 were observed in regions with early-organised pulmonary thrombi, myofibroblasts and fibrosis. Microarray and high-resolution microscopy analysis could localise ANGPT2 overexpression to endothelial cells, and hypoxia and transforming growth factor-ß1 were identified as potential stimuli. Gain-of-function experiments in mice demonstrated that exogenous ANGPT2 administration and transgenic endothelial ANGPT2 overexpression resulted in delayed venous thrombus resolution, and thrombi were characterised by lower TIE2 phosphorylation and fewer microvessels. CONCLUSION: Our findings suggest that ANGPT2 delays venous thrombus resolution and that overexpression of ANGPT2 contributes to thrombofibrosis and may thus support the transition from pulmonary embolism to CTEPH.

Survival and quality of life after early discharge in low-risk pulmonary embolism.

INTRODUCTION: Early discharge of patients with acute low-risk pulmonary embolism requires validation by prospective trials with clinical and quality-of-life outcomes. METHODS: The multinational Home Treatment of Patients with Low-Risk Pulmonary Embolism with the Oral Factor Xa Inhibitor Rivaroxaban (HoT-PE) single-arm management trial investigated early discharge followed by ambulatory treatment with rivaroxaban. The study was stopped for efficacy after the positive results of the predefined interim analysis at 50% of the planned population. The present analysis includes the entire trial population (576 patients). In addition to 3-month recurrence (primary outcome) and 1-year overall mortality, we analysed self-reported disease-specific (Pulmonary Embolism Quality of Life (PEmb-QoL) questionnaire) and generic (five-level five-dimension EuroQoL (EQ-5D-5L) scale) quality of life as well as treatment satisfaction (Anti-Clot Treatment Scale (ACTS)) after pulmonary embolism. RESULTS: The primary efficacy outcome occurred in three (0.5%, one-sided upper 95% CI 1.3%) patients. The 1-year mortality was 2.4%. The mean±sd PEmb-QoL decreased from 28.9±20.6% at 3 weeks to 19.9±15.4% at 3 months, a mean change (improvement) of -9.1% (p<0.0001). Improvement was consistent across all PEmb-QoL dimensions. The EQ-5D-5L was 0.89±0.12 at 3 weeks after enrolment and improved to 0.91±0.12 at 3 months (p<0.0001). Female sex and cardiopulmonary disease were associated with poorer disease-specific and generic quality of life; older age was associated with faster worsening of generic quality of life. The ACTS burden score improved from 40.5±6.6 points at 3 weeks to 42.5±5.9 points at 3 months (p<0.0001). CONCLUSIONS: Our results further support early discharge and ambulatory oral anticoagulation for selected patients with low-risk pulmonary embolism. Targeted strategies may be necessary to further improve quality of life in specific patient subgroups.

Trends in thrombolytic treatment and outcomes of acute pulmonary embolism in Germany.

AIMS: Pulmonary embolism (PE) is the third most common cardiovascular cause of death; systemic thrombolysis is potentially lifesaving treatment in patients presenting with haemodynamic instability. We investigated trends in the use of systemic thrombolysis and the outcome of patients with acute PE. METHODS AND RESULTS: We analysed data on the characteristics, comorbidities, treatment, and in-hospital outcome of 885 806 PE patients in Germany between 2005 and 2015. Incidence of acute PE was 99/100 000 population/year and increased from 85/100 000 in 2005 to 109/100 000 in 2015 [ß 0.32 (0.26-0.38), P < 0.001]. During the same period, in-hospital case fatality rates decreased from 20.4% to 13.9% [ß -0.51 (-0.52 to -0.49), P < 0.001]. The overall proportion of patients treated with systemic thrombolysis increased from 3.1% in 2005 to 4.4% in 2015 [ß 0.28 (0.25-0.31), P < 0.001]. Thrombolysis was associated with lower in-hospital mortality rates in patients with haemodynamic instability, both in those with shock not necessitating cardiopulmonary resuscitation (CPR) or mechanical ventilation [odds ratio (OR) 0.42 (0.37-0.48), P < 0.001], and in those who underwent CPR [OR 0.92 (0.87-0.97), P = 0.002]. This association was independent from age, sex, and comorbidities. However, systemic thrombolysis was administered to only 23.1% of haemodynamically unstable patients. CONCLUSION: Although the proportion of PE patients treated with systemic thrombolysis increased slightly in Germany between 2005 and 2015, only the minority of haemodynamically unstable patients currently receive this treatment. In the nationwide inpatient cohort, thrombolytic therapy was associated with reduced in-hospital mortality rates in PE patients with shock, and also in those who underwent CPR.

Early discharge and home treatment of patients with low-risk pulmonary embolism with the oral factor Xa inhibitor rivaroxaban: an international multicentre single-arm clinical trial.

AIMS: To investigate the efficacy and safety of early transition from hospital to ambulatory treatment in low-risk acute PE, using the oral factor Xa inhibitor rivaroxaban. METHODS AND RESULTS: We conducted a prospective multicentre single-arm investigator initiated and academically sponsored management trial in patients with acute low-risk PE (EudraCT Identifier 2013-001657-28). Eligibility criteria included absence of (i) haemodynamic instability, (ii) right ventricular dysfunction or intracardiac thrombi, and (iii) serious comorbidities. Up to two nights of hospital stay were permitted. Rivaroxaban was given at the approved dose for PE for ≥3 months. The primary outcome was symptomatic recurrent venous thromboembolism (VTE) or PE-related death within 3 months of enrolment. An interim analysis was planned after the first 525 patients, with prespecified early termination of the study if the null hypothesis could be rejected at the level of α = 0.004 (<6 primary outcome events). From May 2014 through June 2018, consecutive patients were enrolled in seven countries. Of the 525 patients included in the interim analysis, three (0.6%; one-sided upper 99.6% confidence interval 2.1%) suffered symptomatic non-fatal VTE recurrence, a number sufficiently low to fulfil the condition for early termination of the trial. Major bleeding occurred in 6 (1.2%) of the 519 patients comprising the safety population. There were two cancer-related deaths (0.4%). CONCLUSION: Early discharge and home treatment with rivaroxaban is effective and safe in carefully selected patients with acute low-risk PE. The results of the present trial support the selection of appropriate patients for ambulatory treatment of PE.

Lysed Erythrocyte Membranes Promote Vascular Calcification.

BACKGROUND: Intraplaque hemorrhage promotes atherosclerosis progression, and erythrocytes may contribute to this process. In this study we examined the effects of red blood cells on smooth muscle cell mineralization and vascular calcification and the possible mechanisms involved. METHODS: Erythrocytes were isolated from human and murine whole blood. Intact and lysed erythrocytes and their membrane fraction or specific erythrocyte components were examined in vitro using diverse calcification assays, ex vivo by using the murine aortic ring calcification model, and in vivo after murine erythrocyte membrane injection into neointimal lesions of hypercholesterolemic apolipoprotein E-deficient mice. Vascular tissues (aortic valves, atherosclerotic carotid artery specimens, abdominal aortic aneurysms) were obtained from patients undergoing surgery. RESULTS: The membrane fraction of lysed, but not intact human erythrocytes promoted mineralization of human arterial smooth muscle cells in culture, as shown by Alizarin red and van Kossa stain and increased alkaline phosphatase activity, and by increased expression of osteoblast-specific transcription factors (eg, runt-related transcription factor 2, osterix) and differentiation markers (eg, osteopontin, osteocalcin, and osterix). Erythrocyte membranes dose-dependently enhanced calcification in murine aortic rings, and extravasated CD235a-positive erythrocytes or Perl iron-positive signals colocalized with calcified areas or osteoblast-like cells in human vascular lesions. Mechanistically, the osteoinductive activity of lysed erythrocytes was localized to their membrane fraction, did not involve membrane lipids, heme, or iron, and was enhanced after removal of the nitric oxide (NO) scavenger hemoglobin. Lysed erythrocyte membranes enhanced calcification to a similar extent as the NO donor diethylenetriamine-NO, and their osteoinductive effects could be further augmented by arginase-1 inhibition (indirectly increasing NO bioavailability). However, the osteoinductive effects of erythrocyte membranes were reduced in human arterial smooth muscle cells treated with the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide or following inhibition of NO synthase or the NO receptor soluble guanylate cyclase. Erythrocytes isolated from endothelial NO synthase-deficient mice exhibited a reduced potency to promote calcification in the aortic ring assay and after injection into murine vascular lesions. CONCLUSIONS: Our findings in cells, genetically modified mice, and human vascular specimens suggest that intraplaque hemorrhage with erythrocyte extravasation and lysis promotes osteoblastic differentiation of smooth muscle cells and vascular lesion calcification, and also support a role for erythrocyte-derived NO.

Prognostic value of right ventricular dysfunction or elevated cardiac biomarkers in patients with low-risk pulmonary embolism: a systematic review and meta-analysis.

AIMS: Patients with acute pulmonary embolism (PE) classified as low risk by the Pulmonary Embolism Severity Index (PESI), its simplified version (sPESI), or the Hestia criteria may be considered for early discharge. We investigated whether the presence of right ventricular (RV) dysfunction may aggravate the early prognosis of these patients. METHODS AND RESULTS: We did a systematic review and meta-analysis of studies including low-risk patients with acute PE to investigate the prognostic value of RV dysfunction. Diagnosis of RV dysfunction was based on echocardiography or computed tomography pulmonary angiography. In addition, we investigated the prognostic value of elevated troponin or natriuretic peptide levels. The primary outcome was all-cause mortality at 30 days or during hospitalization. We included 22 studies (N = 3295 low-risk patients) in the systematic review: 21 were selected for quantitative analysis. Early all-cause mortality rates in patients with vs. without RV dysfunction on imaging were 1.8% [95% confidence interval (CI) 0.9-3.5%] vs. 0.2% (95% CI 0.03-1.7%), respectively, [odds ratio (OR) 4.19, 95% CI 1.39-12.58]. For troponins, rates were 3.8% (95% CI 2.1-6.8%) vs. 0.5% (95% CI 0.2-1.3%), (OR 6.25, 95% CI 1.95-20.05). For natriuretic peptides, only data on early PE-related mortality were available: rates were 1.7% (95% CI 0.4-6.9%) vs. 0.4% (95% CI 0.1-1.1%), (OR 3.71, 95% CI 0.81-17.02). CONCLUSIONS: In low-risk patients with acute PE, the presence of RV dysfunction on admission was associated with early mortality. Our results may have implications for the management of patients who appear at low risk based on clinical criteria alone, but present with RV dysfunction as indicated by imaging findings or laboratory markers.

Differential impact of syncope on the prognosis of patients with acute pulmonary embolism: a systematic review and meta-analysis.

Aims: Controversial reports exist in the literature regarding the prognostic role and therapeutic implications of syncope in patients with acute pulmonary embolism (PE). We conducted a systematic review and meta-analysis to investigate the association between syncope and short-term adverse outcomes, taking into account the presence or absence of haemodynamic compromise at acute PE presentation. Methods and results: The literature search identified 1664 studies, 29 of which were included for a total of 21 956 patients with PE (n = 3706 with syncope). Syncope was associated with higher prevalence of haemodynamic instability [odds ratio (OR) 3.50; 95% confidence interval (CI) 2.67-4.58], as well as with echocardiographic signs of right ventricular (RV) dysfunction (OR 2.10; CI 1.60-2.77) at presentation. Patients with syncope had a higher risks of all-cause early (either in-hospital or within 30 days) death (OR 1.73; CI 1.22-2.47) and PE-related 30-day adverse outcomes (OR 2.00; CI 1.11-3.60). The absolute risk difference (95% CI) for all-cause death was +6% (+1% to +10%) in studies including unselected patients, but it was -1% (-2% to +1%) in studies restricted to normotensive patients. We observed no prognostic impact of syncope in studies with a lower score at formal quality assessment and in those conducted retrospectively. Conclusion: Syncope as a manifestation of acute PE was associated with a higher prevalence of haemodynamic instability and RV dysfunction at presentation, and an elevated risk for early PE-related adverse outcomes. The association with an increased risk of early death appeared more prominent in studies including unselected patients, when compared with those focusing on normotensive patients only.