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.

Modelling Costs of Interventional Pulmonary Embolism Treatment: Implications of US Trends for a European Healthcare System.

BACKGROUND: Catheter-directed treatment (CDT) of acute pulmonary embolism (PE) is entering a growth phase in Europe following a steady increase in the United States (US) in the past decade, but the potential economic impact on European healthcare systems remains unknown. METHODS AND RESULTS: We built two statistical models for the monthly trend of proportion of CDT among patients with severe (intermediate- or high-risk) PE in the US. The conservative model was based on admission data from the National Inpatient Sample (NIS) 2016-2020, and the model reflecting increasing access to advanced treatment from the PERTTM national quality assurance database registry 2018-2021. By applying these models to the forecast of annual PE-related hospitalizations in Germany, we calculated the annual number of severe PE cases and the expected increase in CDT use for the period 2025-2030. The NIS-based model yielded a slow increase, reaching 3.1% (95% CI 3.0-3.2%) among all hospitalizations with PE in 2030; in the PERT-based model, increase would be steeper, reaching 8.7% (8.3-9.2%). Based on current reimbursement rates, we estimated an increase of annual costs for PE-related hospitalizations in Germany ranging from 15.3 to 49.8 million euros by 2030. This calculation does not account for potential cost savings, including those from reduced length of hospital stay. CONCLUSION: Our approach and results, which may be adapted to other European healthcare systems, provide a benchmark for healthcare costs expected to result from CDT. Data from ongoing trials on clinical benefits and cost savings are needed to determine cost-effectiveness and inform reimbursement decisions.

Prospective Multicenter International Registry of Ultrasound-Facilitated Catheter-Directed Thrombolysis in Intermediate-High and High-Risk Pulmonary Embolism (KNOCOUT PE).

BACKGROUND: Prior clinical trials have demonstrated the efficacy of ultrasound-facilitated catheter-directed thrombolysis (USCDT) for the treatment of acute intermediate-risk pulmonary embolism (PE) using reduced thrombolytic doses and shorter infusion durations. However, utilization and safety of such strategies in broader PE populations remain unclear. The KNOCOUT PE (The EKoSoNic Registry of the Treatment and Clinical Outcomes of Patients With Pulmonary Embolism) registry is a multicenter international registry designed to study the treatment of acute PE with USCDT, with focus on safety outcomes. METHODS: The KNOCOUT PE prospective cohort included 489 patients (64 sites internationally) with acute intermediate-high or high-risk PE treated with USCDT between March 2018 and June 2020. Principal safety outcomes were independently adjudicated International Society on Thrombosis and Haemostasis major bleeding at 72 hours post-treatment and mortality within 12 months of treatment. Additional outcomes included change in right ventricular/left ventricular ratio and quality of life measures over 12 months. RESULTS: Mean alteplase (r-tPA [recombinant tissue-type plasminogen activator]) infusion duration was 10.5 hours. Mean total r-tPA dose was 18.1 mg, with 31.0% of patients receiving ≤12 mg. Major bleeding events within 72 hours occurred in 1.6% (8/489) of patients. One patient experienced worsening of a preexisting subdural hematoma after USCDT and therapeutic anticoagulation, which ultimately required surgery. All-cause mortality at 30 days was 1.0% (5/489). Improvement in PE quality of life score was observed with a 41.1% (243/489, 49.7%) and 44.2% (153/489, 31.3%) mean relative reduction by 3 and 12 months, respectively. CONCLUSIONS: In a prospective observational cohort study of patients with intermediate-high and high-risk PE undergoing USCDT, mean r-tPA dose was 18 mg, and the rates of major bleeding and mortality were low. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03426124.

Contribution of pressure and flow changes to resistance reduction after pulmonary arterial hypertension treatment: a meta-analysis of 3898 patients.

Background: Pulmonary arterial hypertension (PAH)-targeted therapies exert significant haemodynamic changes; however, systematic synthesis is currently lacking. Methods: We searched PubMed, CENTRAL and Web of Science for studies evaluating mean pulmonary artery pressure (mPAP), cardiac index/cardiac output (CI/CO) and pulmonary vascular resistance (PVR) of PAH-targeted therapies either in monotherapy or combinations as assessed by right heart catheterisation in treatment-naïve PAH patients. We performed a random-effects meta-analysis with meta-regression. Results: We included 68 studies (90 treatment groups) with 3898 patients (age 47.4±13.2 years, 74% women). In studies with small PVR reduction (<4 WU), CI/CO increase (R2=62%) and not mPAP reduction (R2=24%) was decisive for the PVR reduction (p<0.001 and p=0.36, respectively, in the multivariable meta-regression model); however, in studies with large PVR reduction (>4 WU), both CI/CO increase (R2=72%) and mPAP reduction (R2=35%) contributed significantly to the PVR reduction (p<0.001 and p=0.01, respectively). PVR reduction as a percentage of the pre-treatment value was more pronounced in the oral+prostanoid intravenous/subcutaneous combination therapy (mean difference -50.0%, 95% CI -60.8- -39.2%), compared to oral combination therapy (-41.7%, -47.6- -35.8%), prostanoid i.v./s.c. monotherapy (-31.8%, -37.6- -25.9%) and oral monotherapy (-21.6%, -25.4- -17.8%). Changes in haemodynamic parameters were significantly associated with changes in functional capacity of patients with PAH as expressed by the 6-min walking distance. Conclusion: Combination therapies, especially with the inclusion of parenteral prostanoids, lead to remarkable haemodynamic improvement in treatment-naïve PAH patients and may unmask the contribution of mPAP reduction to the overall PVR reduction in addition to the increase in CO.

Healthcare resource utilisation and associated costs after low-risk pulmonary embolism: pre-specified analysis of the Home Treatment of Pulmonary Embolism (HoT-PE) study.

BACKGROUND: Pulmonary embolism (PE) and its sequelae impact healthcare systems globally. Low-risk PE patients can be managed with early discharge strategies leading to cost savings, but post-discharge costs are undetermined. PURPOSE: To define healthcare resource utilisation and overall costs during follow-up of low-risk PE. METHODS: We used an incidence-based, bottom-up approach and calculated direct and indirect costs over 3-month follow-up after low-risk PE, with data from the Home Treatment of Patients with Low-Risk Pulmonary Embolism (HoT-PE) cohort study. RESULTS: Average 3-month costs per patient having suffered low-risk PE were 7029.62 €; of this amount, 4872.93 € were associated with PE, accounting to 69.3% of total costs. Specifically, direct costs totalled 3019.33 €, and of those, 862.64 € (28.6%) were associated with PE. Anticoagulation (279.00 €), rehospitalisations (296.83 €), and ambulatory visits (194.95 €) comprised the majority of the 3-month direct costs. The remaining costs amounting to 4010.29 € were indirect costs due to loss of productivity. CONCLUSION: In a patient cohort with acute low-risk PE followed over 3 months, the majority of costs were indirect costs related to productivity loss, whereas direct, PE-specific post-discharge costs were low. Effective interventions are needed to reduce the burden of PE and associated costs, especially those related to productivity loss.

Prevalence and Prognostic Role of Lymphedema in Patients with Deep Venous Thrombosis and Thrombophlebitis.

Background: Deep venous thrombosis (DVT) poses a substantial disease burden. Lymphedema may present with similar symptoms making the diagnosis process more difficult. Data on the epidemiology of lymphedema are lacking. Methods: The German nationwide inpatient sample served to analyze all patients hospitalized owing to DVT and/or thrombophlebitis (referred to as DVT) of the legs in Germany between 2005 and 2020. We stratified these patients for additional lymphedema and analyzed the impact of lymphedema on adverse in-hospital events. Results: Overall, 1,136,574 hospitalizations related to DVT were recorded in Germany during 2005-2020 (53.3% women; 51.3% aged ≥70 years). Lymphedema was coded in 9974 (0.9%) patient-cases (82.0% not elsewhere classified, 17.7% secondary lymphedema). Annual numbers of hospitalizations with lymphedema among DVT patients increased from 450 (2005) to 613 (2016) (ß 0.57; 95% confidence interval [CI]: 0.48-0.66], p < 0.001) and decreased thereafter. Despite similar age, DVT patients with lymphedema had higher prevalence of cardiovascular diseases, chronic organ failure, and all types of investigated cancer. Prevalence of pulmonary embolism (PE) with shock/CPR (4.1% vs. 1.5%), acute renal failure (6.7% vs. 2.5%), and stroke (5.2% vs. 4.2%) was higher in DVT patients with lymphedema than without. Lymphedema was independently associated with PE with shock/CPR (OR: 2.1; 95% CI: 1.9-2.3) as well as death (OR: 1.3; 95% CI: 1.2-1.4). Conclusions: Comorbidity conditions like cancer, obesity, and cardiovascular risk factors, and also infectious complications, were more prevalent in DVT patients with lymphedema than in those without. Lymphedema was independently associated with severe in-hospital complications, particularly when its genesis was related to severe comorbidities.

Functional capacity and dyspnea during follow-up after acute pulmonary embolism.

BACKGROUND: Dissecting the determinants of functional capacity during long-term follow-up after acute pulmonary embolism (PE) can help to better characterize a patient population with persisting limitation. METHODS: In a prospective cohort study, consecutive unselected survivors of acute PE underwent 3- and 12-month follow-up, including six-minute walking distance (6MWD) and dyspnea assessment with the modified Medical Research Council (mMRC) scale. We used reference equations adjusting for age, sex, and anthropometric measurements to define abnormal 6MWD. RESULTS: Overall, 323 of 363 (89.0%) patients had at least one recorded 6MWD value at one year. At 3 months, the prevalence of abnormal 6MWD was 21.9% and at 12 months it was 18.3%. At 3 and 12 months, 58.8% and 52.1% with abnormal 6MWD did not report dyspnea, respectively. On average and during follow-up, 6MWD significantly improved with time, while the mMRC dyspnea scale did not. Abnormal 6MWD was associated with younger age (odds ratio per decade, 0.91; 95% CI, 0.88-0.94), higher body mass index (1.10; 1.03-1.17), smoking (3.53; 1.34-9.31), intermediate- or high-risk PE (3.21; 1.21-8.56), and higher mMRC grading (2.28; 1.59-3.27). Abnormal 6MWD at 3 months was associated with the prospectively defined endpoint of post-PE impairment (3.72; 1.50-9.28) and with poor disease-specific and generic health-related quality of life. CONCLUSION: Three months after PE, 37% of patients reported dyspnea and 22% had abnormal 6MWD. After a year, 20% still had abnormal 6MWD. Dyspnea correlated with abnormal 6MWD, but over 50% of patients with abnormal 6MWD did not report dyspnea. Abnormal 6MWD predicted subsequent post-pulmonary embolism impairment and worse long-term quality of life. CLINICAL TRIAL REGISTRATION: German Clinical Trials Register Identifier DRKS00005939.

Pharmacological Treatments in Heart Failure With Mildly Reduced and Preserved Ejection Fraction: Systematic Review and Network Meta-Analysis.

BACKGROUND: Medical treatment for heart failure (HF) with preserved ejection (HFpEF) and with mildly reduced ejection fraction (HFmrEF) has weaker evidence compared with reduced ejection fraction, despite recent trials with an angiotensin receptor neprilysin inhibitor (ARNI) and sodium-glucose cotransporter-2 inhibitors (SGLT2i). OBJECTIVES: We aimed to estimate the aggregate therapeutic benefit of drugs for HFmrEF and HFpEF. METHODS: We performed a systematic review of MEDLINE, CENTRAL, and Web of Science for randomized trials including patients with HF and left ventricular ejection fraction (LVEF) >40%, treated with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (analyzed together as renin-angiotensin system inhibitors [RASi]), beta-blockers (BBs), mineralocorticoid receptor antagonists (MRAs), digoxin, ARNI, and SGLT2i. An additive component network meta-analysis was performed. The primary outcome was a composite of cardiovascular (CV) death and first hospitalization for heart failure (HHF); secondary outcomes were CV death, total HHF, and all-cause mortality. RESULTS: We identified 13 studies with a total of 29,875 patients and a mean LVEF of 56.3% ± 8.7%. ARNI, MRA, and SGLT2i separately, but not RASi, BB, or digoxin, reduced the primary composite outcome compared with placebo. The combination of ARNI, BB, MRA, and SGLT2i was the most effective (HR: 0.47 [95% CI: 0.31-0.70]); this was largely explained by the triple combination of ARNI, MRA, and SGLT2i (HR: 0.56 [95% CI 0.43-0.71]). Results were similar for CV death (HR: 0.63 [95% CI 0.43-0.91] for ARNI, MRA, and SGLT2i) or total HHF (HR: 0.49 [95% CI 0.33-0.71] for ARNI, MRA, and SGLT2i) alone. In a subgroup analysis, only SGLT2i had a consistent benefit among all LVEF subgroups, whereas the triple combination had the greatest benefit in HFmrEF, robust benefit in patients with LVEF 50% to 59%, and a statistically marginal benefit in patients with LVEF ≥60%. CONCLUSIONS: In patients with HF and LVEF>40%, the quadruple combination of ARNI, BB, MRA, and SGLT2i provides the largest reduction in the risk of CV death and HHF; driven by the robust effect of the triple combination of ARNI, MRA, and SGLT2i. The benefit was more pronounced in HFmrEF patients.

A nationwide analysis of reperfusion therapies for pulmonary embolism in older patients with frailty.

BACKGROUND: Reperfusion therapy is challenging in the elderly. Catheter-directed therapies are an alternative for higher-risk pulmonary embolism (PE) patients if systemic thrombolysis (ST) is contraindicated or has failed. Their safety has not been evaluated in specific vulnerable populations. AIMS: We aimed to assess the safety of reperfusion therapies in elderly and frail patients in the real world. METHODS: In the US Nationwide Inpatient Sample from 2016 to 2020, we identified hospitalisations of patients ≥65 years with PE and defined a frailty subgroup using the Johns Hopkins Adjusted Clinical Groups frailty-defining diagnosis indicator. We investigated reperfusion therapies (ST, catheter-directed thrombolysis [CDT], catheter-based thrombectomy [CBT], surgical embolectomy [SE]) and their associated safety outcomes (overall and major bleeding). RESULTS: Among 980,245 hospitalisations of patients ≥65 years with PE (28.0% frail), reperfusion therapies were used in 4.9% (17.6% among high-risk PE). ST utilisation remained stable, while the use of catheter-directed therapies increased from 1.7% in 2016 to 3.2% in 2020. Among all hospitalisations with reperfusion, CDT, compared to ST, was associated with reduced major bleeding (5.8% vs 12.2%, odds ratio [OR] 0.58, 95% confidence interval [CI]: 0.49-0.70); these results also applied to frail patients. CBT, compared to SE, was also associated with reduced major bleeding (11.0% vs 22.4%, OR 0.63, 95% CI: 0.43-0.91), but not among frail patients. These differences were particularly significant in patients with non-high-risk PE. Differences persisted for overall bleeding as well. CONCLUSIONS: Catheter-directed therapies may be a safer alternative to classical reperfusion therapies for elderly and frail patients with PE requiring reperfusion treatment.

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.

Circulating microRNAs predict recurrence and death following venous thromboembolism.

BACKGROUND: Recurrent events frequently occur after venous thromboembolism (VTE) and remain difficult to predict based on established genetic, clinical, and proteomic contributors. The role of circulating microRNAs (miRNAs) has yet to be explored in detail. OBJECTIVES: To identify circulating miRNAs predictive of recurrent VTE or death, and to interpret their mechanistic involvement. METHODS: Data from 181 participants of a cohort study of acute VTE and 302 individuals with a history of VTE from a population-based cohort were investigated. Next-generation sequencing was performed on EDTA plasma samples to detect circulating miRNAs. The endpoint of interest was recurrent VTE or death. Penalized regression was applied to identify an outcome-relevant miRNA signature, and results were validated in the population-based cohort. The involvement of miRNAs in coregulatory networks was assessed using principal component analysis, and the associated clinical and molecular phenotypes were investigated. Mechanistic insights were obtained from target gene and pathway enrichment analyses. RESULTS: A total of 1950 miRNAs were detected across cohorts after postprocessing. In the discovery cohort, 50 miRNAs were associated with recurrent VTE or death (cross-validated C-index, 0.65). A weighted miRNA score predicted outcome over an 8-year follow-up period (HRSD, 2.39; 95% CI, 1.98-2.88; P < .0001). The independent validation cohort validated 20 miRNAs (ORSD for score, 3.47; 95% CI, 2.37-5.07; P < .0001; cross-validated-area under the curve, 0.61). Principal component analysis revealed 5 miRNA networks with distinct relationships to clinical phenotype and outcome. Mapping of target genes indicated regulation via transcription factors and kinases involved in signaling pathways associated with fibrinolysis. CONCLUSION: Circulating miRNAs predicted the risk of recurrence or death after VTE over several years, both in the acute and chronic phases.

Clinical profile and outcome of isolated pulmonary embolism: a systematic review and meta-analysis.

Background: Isolated pulmonary embolism (PE) appears to be associated with a specific clinical profile and sequelae compared to deep vein thrombosis (DVT)-associated PE. The objective of this study was to identify clinical characteristics that discriminate both phenotypes, and to characterize their differences in clinical outcome. Methods: We performed a systematic review and meta-analysis of studies comparing PE phenotypes. A systematic search of the electronic databases PubMed and CENTRAL was conducted, from inception until January 27, 2023. Exclusion criteria were irrelevant content, inability to retrieve the article, language other than English or German, the article comprising a review or case study/series, and inappropriate study design. Data on risk factors, clinical characteristics and clinical endpoints were pooled using random-effects meta-analyses. Findings: Fifty studies with 435,768 PE patients were included. In low risk of bias studies, 30% [95% CI 19-42%, I 2 = 97%] of PE were isolated. The Factor V Leiden [OR: 0.47, 95% CI 0.37-0.58, I 2 = 0%] and prothrombin G20210A mutations [OR: 0.55, 95% CI 0.41-0.75, I 2 = 0%] were significantly less prevalent among patients with isolated PE. Female sex [OR: 1.30, 95% CI 1.17-1.45, I 2 = 79%], recent invasive surgery [OR: 1.31, 95% CI 1.23-1.41, I 2 = 65%], a history of myocardial infarction [OR: 2.07, 95% CI 1.85-2.32, I 2 = 0%], left-sided heart failure [OR: 1.70, 95% CI 1.37-2.10, I 2 = 76%], peripheral artery disease [OR: 1.36, 95% CI 1.31-1.42, I 2 = 0%] and diabetes mellitus [OR: 1.23, 95% CI 1.21-1.25, I 2 = 0%] were significantly more frequently represented among isolated PE patients. In a synthesis of clinical outcome data, the risk of recurrent VTE in isolated PE was half that of DVT-associated PE [RR: 0.55, 95% CI 0.44-0.69, I 2 = 0%], while the risk of arterial thrombosis was nearly 3-fold higher [RR: 2.93, 95% CI 1.43-6.02, I 2 = 0%]. Interpretation: Our findings suggest that isolated PE appears to be a specific entity that may signal a long-term risk of arterial thrombosis. Randomised controlled trials are necessary to establish whether alternative treatment regimens are beneficial for this patient subgroup. Funding: None.

Social determinants of health in pulmonary embolism management and outcome in hospitals: Insights from the United States nationwide inpatient sample.

Background: The role of social determinants in the treatment and course of acute pulmonary embolism (PE) is understudied. Objective: To investigate the association between social determinants of health with in-hospital management and early clinical outcomes following acute PE. Methods: We identified hospitalizations of adults with acute PE discharge diagnosis from the nationwide inpatient sample (2016-2018). Multivariable regression was used to investigate the association between race/ethnicity, type of expected primary payer, and income with the use of advanced PE therapies (thrombolysis, catheter-directed treatment, surgical embolectomy, extracorporeal membrane oxygenation), length of stay, hospitalization charges, and in-hospital death. Results: A total of 1,124,204 hospitalizations with a PE diagnosis were estimated from the 2016-2018 nationwide inpatient sample, corresponding to a hospitalization rate of 14.9/10,000 adult persons-year. The use of advanced therapies was lower in Black and Asian/Pacific Islander (vs. White patients: adjusted odds ratio [ORadjusted], 0.87; 95% confidence interval [CI], 0.81-0.92 and ORadjusted 0.76; 95% CI, 0.59-0.98) and in Medicare- or Medicaid-insured (vs. privately-insured; ORadjusted, 0.73; 95% CI, 0.69-0.77 and ORadjusted, 0.68; 95% CI, 0.63-0.74), although they had the greatest length of stay and hospitalization charges. In-hospital mortality was higher in the lowest income quartile (vs. highest quartile; ORadjusted, 1.09; 95% CI, 1.02-1.17). Among high-risk PE, patients of other than the White race had the highest in-hospital mortality. Conclusion: We observed inequalities in advanced therapies used for acute PE and higher in-hospital mortality in races other than White. Low socioeconomic status was also associated with lesser use of advanced treatment modalities and greater in-hospital mortality. Future studies should further explore and consider the long-term impact of social inequities in PE management.

Unsupervised clustering of venous thromboembolism patients by clinical features at presentation identifies novel endotypes that improve prognostic stratification.

BACKGROUND: Individuals with acute venous thromboembolism (VTE) constitute a heterogeneous group of patients with diverse clinical characteristics and outcome. OBJECTIVES: To identify endotypes of individuals with acute VTE based on clinical characteristics at presentation through unsupervised cluster analysis and to evaluate their molecular proteomic profile and clinical outcome. METHODS: Data from 591 individuals from the Genotyping and Molecular phenotyping of Venous thromboembolism (GMP-VTE) project were explored. Hierarchical clustering was applied to 58 variables to define VTE endotypes. Clinical characteristics, three-year incidence of thromboembolic events or death, and acute-phase plasma proteomics were assessed. RESULTS: Four endotypes were identified, exhibiting different patterns of clinical characteristics and clinical course. Endotype 1 (n = 300), comprising older individuals with comorbidities, had the highest incidence of thromboembolic events or death (HR [95 % CI]: 3.76 [1.96-7.19]), followed by endotype 4 (n = 127) (HR [95 % CI]: 2.55 [1.26-5.16]), characterised by men with history of VTE and provoking risk factors, and endotype 3 (n = 57) (HR [95 % CI]: 1.57 [0.63-3.87]), composed of young women with provoking risk factors, vs. reference endotype 2 (n = 107). The reference endotype was constituted by individuals diagnosed with PE without comorbidities, who had the lowest incidence of the investigated endpoint. Differentially expressed proteins associated with the endotypes were related to distinct biological processes, supporting differences in molecular pathophysiology. The endotypes had superior prognostic ability compared to existing risk stratifications such as provoked vs unprovoked VTE and D-dimer levels. CONCLUSION: Four endotypes of VTE were identified by unsupervised phenotype-based clustering that diverge in clinical outcome and plasmatic protein signature. This approach might support the future development of individualized treatment in VTE.

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.

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.

Preexisting Chronic Thromboembolic Pulmonary Hypertension in Acute Pulmonary Embolism.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is considered a complication of pulmonary embolism (PE). However, signs of CTEPH may exist in patients with a first symptomatic PE. RESEARCH QUESTION: Which radiologic findings on CT pulmonary angiography (CTPA) at the time of acute PE could indicate the presence of preexisting CTEPH? STUDY DESIGN AND METHODS: This study included unselected patients with acute PE who were prospectively followed up for 2 years with a structured visit schedule. Two expert radiologists independently assessed patients' baseline CTPAs for preexisting CTEPH; in case of disagreement, a decision was reached by a 2:1 majority with a third expert radiologist. In addition, the radiologists checked for predefined individual parameters suggesting chronic PE and pulmonary hypertension. RESULTS: Signs of chronic PE or CTEPH at baseline were identified in 46 of 303 included patients (15%). Intravascular webs, arterial narrowing or retraction, dilated bronchial arteries, and right ventricular hypertrophy were the main drivers of the assessment. Five (1.7%) patients were diagnosed with CTEPH during follow-up. All four patients diagnosed with CTEPH early (83-108 days following acute PE) were found in enriched subgroups based on the experts' overall assessment or fulfilling a minimum number of the predefined radiologic criteria at baseline. The specificity of preexisting CTEPH diagnosis and the level of radiologists' agreement improved as the number of required criteria increased. INTERPRETATION: Searching for predefined radiologic parameters suggesting preexisting CTEPH at the time of acute PE diagnosis may allow for targeted follow-up strategies and risk-adapted CTEPH screening, thus facilitating earlier CTEPH diagnosis.