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.

Developmental or Procedural Vena Cava Interruption and Venous Thromboembolism: A Review.

The inferior vena cava (IVC) and superior vena cava are the main conduits of the systemic venous circulation into the right atrium. Developmental or procedural interruptions of vena cava might predispose to stasis and deep vein thrombosis (DVT) distal to the anomaly and may impact the subsequent rate of pulmonary embolism (PE). This study aimed to review the various etiologies of developmental or procedural vena cava interruption and their impact on venous thromboembolism. A systematic search was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines per each clinical question. For management questions with no high-quality evidence and no mutual agreements between authors, Delphi methods were used. IVC agenesis is the most common form of congenital vena cava interruption, is associated with an increased risk of DVT, and should be suspected in young patients with unexpected extensive bilateral DVT. Surgical techniques for vena cava interruption (ligation, clipping, and plication) to prevent PE have been largely abandoned due to short-term procedural risks and long-term complications, although survivors of prior procedures are occasionally encountered. Vena cava filters are now the most commonly used method of procedural interruption, frequently placed in the infrarenal IVC. The most agreed-upon indication for vena cava filters is for patients with acute venous thromboembolism and coexisting contraindications to anticoagulation. Familiarity with different forms of vena cava interruption and their local and systemic adverse effects is important to minimize complications and thrombotic events.

The prognostic value of blood cellular indices in pulmonary embolism.

Prognostication in acute pulmonary embolism (PE) requires reliable markers. While cellular indices such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) appear promising, their utility in PE prognostication needs further exploration. We utilized data from the RIETE registry and the Loyola University Medical Center (LUMC) to assess the prognostic value of NLR, PLR, and SII in acute PE, using logistic regression models. The primary outcome was 30-day all-cause mortality. We compared their prognostic value versus the simplified Pulmonary Embolism Severity Index (sPESI) alone. We included 10 085 patients from RIETE and 700 from the LUMC. Thirty-day mortality rates were 4.6% and 8.3%, respectively. On multivariable analysis, an elevated NLR (>7.0) was associated with increased mortality (adjusted odds ratio [aOR]: 3.46; 95% CI: 2.60-4.60), outperforming the PLR > 220 (aOR: 2.36; 95% CI: 1.77-3.13), and SII > 1600 (aOR: 2.52; 95% CI: 1.90-3.33). The c-statistic for NLR in patients with low-risk PE was 0.78 (95% CI: 0.69-0.86). Respective numbers were 0.66 (95% CI: 0.63-0.69) and 0.68 (95% CI: 0.59-0.76) for intermediate-risk and high-risk patients. These findings were mirrored in the LUMC cohort. Among 9810 normotensive patients in RIETE, those scoring 0 points in sPESI and with an NLR ≤ 7.0 (35% of the population) displayed superior sensitivity (97.1%; 95% CI: 95.5-98.7) and negative predictive value (99.7%; 95% CI: 99.5-99.8) than sPESI alone (87.1%; 95% CI: 83.9-90.3, and 98.7%; 95% CI: 98.4-99.1, respectively) for 30-day mortality. The NLR is a significant prognostic marker for 30-day mortality in PE patients, especially useful to identify patients with very low-risk PE.

Outcomes of venous thromboembolism in patients with inherited thrombophilia treated with direct oral anticoagulants: insights from the RIETE registry.

While direct oral anticoagulants (DOACs) are frequently used to treat venous thromboembolism (VTE), the outcomes of patients with inherited thrombophilia (IT) receiving DOACs for VTE remain understudied. We used data from the international RIETE registry to compare the rates of VTE recurrences, major bleeding, and mortality during anticoagulant treatment in VTE patients with and without IT, grouped by the use of DOACs or standard anticoagulant therapy. Among 103,818 enrolled patients, 21,089 (20.3%) were tested for IT, of whom 8422 (39.9%) tested positive: Protein C deficiency 294, Protein S deficiency 726, Antithrombin deficiency 240, Factor V Leiden 2248, Prothrombin gene mutation 1434, combined IT 3480. Overall, 14,189 RIETE patients (6.2% with IT) received DOACs, and 89,629 standard anticoagulation (8.4% with IT), mostly with heparins followed by vitamin K antagonists. Proportions of patients receiving DOACs did not differ between IT-positive and IT-negative patients. Rates of VTE recurrence on anticoagulant treatment were highest in patients with AT deficiency (P < 0.01). Rates of on-treatment major bleeding and all-cause mortality were lowest among patients with Factor V Leiden (FVL) or PT G20210A mutations, compared with patients who tested negative. Patients with IT who received DOACs had lower rates of major bleeding than those receiving standard anticoagulation. Excluding FVL and Protein S deficiency, patients with IT had lower rates of VTE recurrence with DOACs than with standard anticoagulation. DOACs are equally safe and effective in VTE patients with IT, with lower bleeding rates than those on standard anticoagulation.

Machine learning to predict major bleeding during anticoagulation for venous thromboembolism: possibilities and limitations.

Predictive tools for major bleeding (MB) using machine learning (ML) might be advantageous over traditional methods. We used data from the Registro Informatizado de Enfermedad TromboEmbólica (RIETE) to develop ML algorithms to identify patients with venous thromboembolism (VTE) at increased risk of MB during the first 3 months of anticoagulation. A total of 55 baseline variables were used as predictors. New data prospectively collected from the RIETE were used for further validation. The RIETE and VTE-BLEED scores were used for comparisons. External validation was performed with the COMMAND-VTE database. Learning was carried out with data from 49 587 patients, of whom 873 (1.8%) had MB. The best performing ML method was XGBoost. In the prospective validation cohort the sensitivity, specificity, positive predictive value and F1 score were: 33.2%, 93%, 10%, and 15.4% respectively. F1 value for the RIETE and VTE-BLEED scores were 8.6% and 6.4% respectively. In the external validation cohort the metrics were 10.3%, 87.6%, 3.5% and 5.2% respectively. In that cohort, the F1 value for the RIETE score was 17.3% and for the VTE-BLEED score 9.75%. The performance of the XGBoost algorithm was better than that from the RIETE and VTE-BLEED scores only in the prospective validation cohort, but not in the external validation cohort.

The rationale, design, and methods of a trial to evaluate the efficacy and safety of oxygen therapy in patients with intermediate-risk acute pulmonary embolism.

BACKGROUND: In patients with intermediate-risk pulmonary embolism (PE), reversal of hypoxic vasoconstriction could constitute a target for treatment that protects the right ventricular (RV) function until endogenous fibrinolysis occurs. The Air vs oxygen for Intermediate-Risk pulmonary embolism (AIR) trial aims to assess the effect of oxygen therapy in patients with intermediate-risk acute PE who do not have hypoxemia at baseline. METHODS AND ANALYSES: AIR is a prospective, multicenter, randomized, open-label, parallel-group, proof-of-concept trial. A total of 90 patients hospitalized with intermediate-risk PE and an oxygen saturation of 90% or higher at baseline will be randomized in a 1:1 fashion to receive supplemental oxygen or ambient air. The primary outcome is a RV/LV diameter ratio equal or less than 1.0 on echocardiography measured 48 hours after the start of treatment. Secondary efficacy outcomes are the numerical change in the ratio of the RV to the LV diameter measured 48 hours and 7 days after the start of treatment, with respect to the baseline ratio measured at randomization. Clinical adverse events will be also collected. RESULTS: Enrollment started in July 2019 and is expected to proceed until 2022. Median age of the first 50 patients was 74 years (interquartile range, 61-81), and 50% were female. CONCLUSIONS: This multicenter trial will provide information about the value of supplemental oxygen in patients with intermediate-risk acute PE who do not have hypoxemia at baseline. The results will contribute to research that may assist patients with intermediate-risk PE in the future.

Pulmonary Embolism in Patients with COVID-19: Comparison between Different Care Settings.

The clinical characteristics and outcomes of patients with coronavirus disease 2019 (COVID-19) who develop pulmonary embolism (PE) in the full spectrum of patient care settings need to be elucidated. The aim of this study was to compare the clinical characteristics, treatment, and 90-day outcomes in patients diagnosed with PE while recovering from COVID-19 in the outpatient setting versus those who were diagnosed with PE while being hospitalized with COVID-19. Data from the international Registro Informatizado de Enfermedad TromboEmbólica (RIETE) registry were used. The major study outcomes were all-cause death, major bleeding, and venous thromboembolism (VTE) recurrences during the first 90 days after PE. From March 2020 to March 2021, 737 patients with COVID-19 experienced acute PE. Of these, 340 (46%) were recovering from COVID-19 as outpatients (267 patients who had been treated at home for COVID-19 and 73 discharged after being hospitalized with COVID-19). Compared with inpatients with COVID-19, those recovering in the outpatient setting upon PE were less likely to be men (odds ratio [OR]: 0.54; 95% confidence interval [CI]: 0.40-0.72) and less likely to have hypertension (OR: 0.55; 95% CI: 0.41-0.74) or diabetes (OR: 0.51; 95% CI: 0.33-0.76). At 90-day follow-up, eight patients (none recovering from COVID-19 as outpatient vs. 2.4% of inpatients with COVID-19) developed recurrent VTE, 34 (1.9 vs. 7.9%) had major bleeding, and 128 (10 vs. 24%) died. On multivariable analysis, inpatients with COVID-19 were at a higher risk of major bleeding (adjusted hazard ratio [HR]: 6.80; 95% CI: 1.52-30.4) or death (adjusted HR: 2.24; 95% CI: 1.40-3.58). In conclusion, using a large multinational registry of patients with COVID-19 who experienced PE, thromboembolic episodes occurring in those recovering from COVID-19 as outpatients were associated with less ominous outcomes than inpatients with COVID-19.

Sex-Related Differences in Patient Characteristics, Risk Factors, and Symptomatology in Older Adults with Pulmonary Embolism: Findings from the SERIOUS-PE Study.

Sex-specific factors are implicated in pulmonary embolism (PE) presentation in young patients, as indicated by increased risk in pregnancy. Whether sex differences exist in PE presentation, comorbidities, and symptomatology in older adults, the age group in which most PEs occur, remains unknown. We identified older adults (aged ≥65 years) with PE in a large international PE registry replete with information about relevant clinical characteristics (RIETE registry, 2001-2021). To provide national data from the United States, we assessed sex differences in clinical characteristics and risk factors of Medicare beneficiaries with PE (2001-2019). The majority of older adults with PE in RIETE (19,294/33,462, 57.7%) and in the Medicare database (551,492/948,823, 58.7%) were women. Compared with men, women with PE less frequently had atherosclerotic diseases, lung disease, cancer, or unprovoked PE, but more frequently had varicose veins, depression, prolonged immobility, or history of hormonal therapy (p < 0.001 for all). Women less often presented with chest pain (37.3 vs. 40.6%) or hemoptysis (2.4 vs. 5.6%) but more often with dyspnea (84.6 vs. 80.9%) (p < 0.001 for all). Measures of clot burden, PE risk stratification, and use of imaging modalities were comparable between women and men. PE is more common in elderly women than in men. Cancer and cardiovascular disease are more common in men, whereas transient provoking factors including trauma, immobility, or hormone therapy are more common in elderly women with PE. Whether such differences correlate with disparities in treatment or differences in short- or long-term clinical outcomes warrants further investigation.

Comparison of Presentation, Treatment, and Outcomes of Venous Thromboembolism in Long-Term Immobile Patients Based on Age.

BACKGROUND: Chronic immobility is prevalent, especially as people age. However, little is known about venous thromboembolism (VTE) outcomes in this population. OBJECTIVE: To compare the presentation, treatment, and outcomes in chronically immobile (>8 weeks) patients older vs. younger than 75 who presented with VTE. DESIGN: An observational international registry of patients with VTE. PARTICIPANTS: Patients with acute VTE from the "Registro Informatizado Enfermedad TromboEmbolica" (RIETE) registry who were chronically immobile. MAIN MEASURES: Baseline characteristics, presenting signs and symptoms, treatment and outcomes including major bleeding, recurrent VTE, and mortality. KEY RESULTS: Among 4612 immobile patients (mean age 75.7 years, 34% male), 2127 (46%) presented with pulmonary embolism (PE). Patients >75 years presented more often with dyspnea (44% vs. 38%) or altered mental status (23% vs. 8.1%) and less often with chest pain (13% vs. 18%). The median duration of anticoagulation was shorter in older compared with younger patients [126 vs. 169 days]. During the first 90 days of anticoagulation, major bleeding (4.0% vs. 2.2%), PE-related death (2.5% vs. 1.1%), and bleeding-related death (0.78% vs. 0.26%) occurred more frequently among older patients. In 3550 patients who received anticoagulation beyond 90 days, older patients had more major bleeding [4.23 vs. 2.21 events per 100 patient years]. After anticoagulation discontinuation, recurrent VTE and major bleeding occurred in 11.8 and 9.25 and 1.49 and 0.69 events per 100 patient years, respectively, both in similar rates in both groups. In multivariable analysis, after stopping anticoagulation, VTE recurrence was inversely associated with long-term facility residence [OR 0.51 (0.28-0.92)], anemia [OR 0.63 (0.42-0.95)], and anticoagulation duration < 90 days [OR 0.38 (0.27-0.54)]. CONCLUSIONS: Chronically immobilized patients older than 75 years presenting with VTE experience a high rate of adverse events including major bleeding and recurrent VTE. When considering treatment beyond 90 days, we should account for bleeding, recurrence risk, and associated mortality.

Risk for recurrence of symptomatic upper-extremity deep vein thrombosis in patients without cancer: Analysis of three RIETE cohorts.

BACKGROUND: The natural history of patients with a pacemaker-related upper-extremity deep vein thrombosis (UEDVT) has not been consistently studied. METHODS: We used the RIETE registry data to compare the outcomes during anticoagulation and after its discontinuation in noncancer patients with symptomatic UEDVT associated with a pacemaker, other catheters, or no catheter. The major outcome was the composite of symptomatic pulmonary embolism or recurrent DVT. RESULTS: As of February 2022, 2578 patients with UEDVT were included: 156 had a pacemaker-related UEDVT, 557 had other catheters, and 1865 had no catheter. During anticoagulation, 61 patients (2.3%) developed recurrent VTE, 38 had major bleeding (1.4%), and 90 died (3.4%). After its discontinuation, 52 patients (4.4%) had recurrent acute venous thromboembolism (VTE) and six had major bleeding (0.5%). On multivariable analysis, there were no differences among subgroups in the rates of VTE recurrences or major bleeding during anticoagulation. After its discontinuation, patients with a pacemaker-related UEDVT had a higher risk for VTE recurrences than those with no catheter (adjusted OR: 4.59; 95% CI: 1.98-10.6). CONCLUSIONS: Patients with pacemaker-related UEDVT are at increased risk for VTE recurrences after discontinuing anticoagulation. If our findings are validated in adequately designed trials, this may justify changes in the current recommendations on the duration of anticoagulation.

Randomised controlled trial of a prognostic assessment and management pathway to reduce the length of hospital stay in normotensive patients with acute pulmonary embolism.

BACKGROUND: The length of hospital stay (LOS) for acute pulmonary embolism (PE) varies considerably. Whether the upfront use of a PE prognostic assessment and management pathway is effective in reducing the LOS remains unknown. METHODS: We conducted a randomised controlled trial of adults hospitalised for acute PE: patients were assigned either to a prognostic assessment and management pathway involving risk stratification followed by predefined criteria for mobilisation and discharge (intervention group) or to usual care (control group). The primary end-point was LOS. The secondary end-points were the cost of prognostic tests and of hospitalisation, and 30-day clinical outcomes. RESULTS: Of 500 patients who underwent randomisation, 498 were included in the modified intention-to-treat analysis. The median LOS was 4.0 days (interquartile range (IQR) 3.7-4.2 days) in the intervention group and 6.1 days (IQR 5.7-6.5 days) in the control group (p<0.001). The mean total cost of prognostic tests was EUR 174.76 in the intervention group, compared with EUR 233.12 in the control group (mean difference EUR -58.37, 95% CI EUR -84.34- to -32.40). The mean total hospitalisation cost per patient was EUR 2085.66 in the intervention group, compared with EUR 3232.97 in the control group (mean difference EUR -1147.31, 95% CI EUR -1414.97- to -879.65). No significant differences were observed in 30-day readmission (4.0% versus 4.8%), all-cause mortality (2.4% versus 2.0%) or PE-related mortality (0.8% versus 1.2%) rates. CONCLUSIONS: The use of a prognostic assessment and management pathway was effective in reducing the LOS for acute PE.

Sustained low-density lipoprotein-cholesterol <70 mg/dl is associated with improved cardiovascular outcomes in the clinical setting.

BACKGROUND AND AIMS: Clinical trials have shown that intensive low-density lipoprotein cholesterol (LDL-C) lowering improves cardiovascular outcomes among patients with atherosclerotic cardiovascular disease (ASCVD), but data are limited in real clinical practice, particularly for patients with ASCVD informing different territories. METHODS: FRENA was a prospective registry of consecutive outpatients with coronary, cerebrovascular or peripheral artery disease. We compared the incidence of recurrent events in patients with sustained LDL-C levels <70 mg/dl compared with those with ≥70 mg/dl. RESULTS: As of December 2018, 1182 patients were eligible for this study. Among them, 172 (14.5%) had mean LDL-C levels ≤70 mg/dl, and 1010 (85.5%) had <70 mg/dl. Their clinical characteristics at baseline were similar. During 5 years of follow-up, 252 patients (21%) suffered major adverse cardiovascular events (MACE). The incidence rates of MACE were 3.42 events per 100 patient-years (95% confidence interval [95% CI] 2.17-5.14) in patients with levels <70 mg/dl and 5.57 (95% CI, 4.87-6.34) in those with ≥70 mg/dl; the rate ratio was 0.61 (95% CI, 0.39-0.92), p = 0.019. On multivariable analysis, patients with LDL-C levels <70 mg/dl were at lower risk for MACE (hazard ratio [HR]: 0.61 [95% CI, 0.39-0.93] p < 0.05). MACE reduction was driven by a decrease in coronary and peripheral events with no significant effect on stroke. CONCLUSIONS: Long-term sustained LDL-C <70 mg/dl in the clinical practice is associated with reduction in cardiovascular and peripheral vascular events with no apparent effect on stroke.

Major bleeding in patients with pulmonary embolism presenting with syncope.

INTRODUCTION: Syncope has been shown to be a risk factor of bleeding in patients receiving thrombolytic therapy for acute pulmonary embolism (PE). Whether syncope predicts bleeding in a broader population of patients with PE remains unknown. METHODS: We used the RIETE registry data to assess whether initial presentation with syncope could predict bleeding in PE patients receiving anticoagulant therapy, and to explore the association between presence of syncope and timing and site of major bleeding events. RESULTS: Among 45,765 patients with acute PE from March 2001 to January 2021, 6760 (14.8%) had syncope. Patients with syncope were older and more likely to have hypotension, tachycardia, hypoxaemia or elevated troponin levels than those without syncope. They also were more likely to receive thrombolytics. During the first 90 days, 1097 patients (2.4%) suffered major bleeding (gastrointestinal 335, hematoma 271 and intracranial 163) and 3611 died (158 had fatal bleeding). Patients with syncope had a higher rate of major bleeding (odds ratio [OR]: 1.63; 95% CI: 1.41-1.89) and a nonsignificantly higher rate of fatal bleeding (OR: 1.47; 95% CI: 0.99-2.17) than those without syncope. Multivariable analysis confirmed that patients with syncope were at increased risk for major bleeding (adjusted hazard ratio [aHR]: 1.34; 95% CI: 1.15-1.55). On sensitivity analysis, the increased risk for major bleeding was confirmed in patients initially receiving anticoagulant therapy without thrombolytics at 7 days (aHR: 1.47; 95% CI: 1.13-1.91) and 90 days (aHR: 1.33; 95%CI: 1.13-1.56). DISCUSSION: Syncope is a predictor of major bleeding events in patients with PE, even among those receiving anticoagulation monotherapy.

Imaging modalities for confirming pulmonary embolism during pregnancy: results from a multicenter international study.

OBJECTIVES: We explored the variations in use of imaging modalities for confirming pulmonary embolism (PE) according to the trimester of pregnancy. METHODS: We included all pregnant patients with confirmed acute PE from RIETE, a prospective registry of patients with PE (03/2001-02/2020). Imaging modalities included computed tomography pulmonary angiography (CTPA), ventilation-perfusion (V/Q) scan, or presence of signs of acute PE along with imaging-confirmed proximal deep vein thrombosis (pDVT) without pulmonary vascular imaging. We compared the imaging modalities to postpartum patients with PE, and other non-pregnant women with PE. RESULTS: There were 157 pregnant patients (age: 32.7 ± 0.5), 228 postpartum patients (age: 33.9 ± 0.5), and 23,937 non-pregnant non-postpartum women (age: 69.5 ± 0.1). CTPA was the most common modality for confirming PE, from 55.7% in first trimester to 58.3% in second trimester, and 70.0% in third trimester. From first trimester to third trimester, V/Q scanning was used in 21.3%, 16.7%, and 18.3% of cases, respectively. Confirmed pDVT along with the presence of signs/symptoms of PE was the confirmatory modality for PE in 21.3% of patients in first trimester, 19.4% in second trimester, and 6.7% in third trimester. The proportion of postpartum patients confirmed with CTPA (85.5%) was comparable to that of non-pregnant non-postpartum women (83.2%). From the first trimester of pregnancy to postpartum period, there was a linear increase in the proportion of patients with PE diagnosed with CTPA (p = 0.039). CONCLUSION: CTPA was the primary modality for confirming PE in all trimesters of pregnancy, although its proportional use was higher in later stages of pregnancy. KEY POINTS: • Computed tomography pulmonary angiography (CTPA) was the primary modality of diagnosis in all trimesters of pregnancy among patients with confirmed pulmonary embolism, even in the first trimester. • From the first trimester of pregnancy to postpartum period, there was a linear increase in the proportion of patients with pulmonary embolism who were diagnosed based on CTPA. • In the postpartum period, use of CTPA as the modality to confirm pulmonary embolism was comparable to non-pregnant patients.

Prognostic impact of acute kidney injury in patients with acute pulmonary embolism data from the RIETE registry.

Risk stratification is recommended for patients with pulmonary embolism (PE), and usually starts with the assessment of the hemodynamic status and the simplified Pulmonary Embolism Severity Index (sPESI). The influence of acute kidney injury (AKI) on the prognostic stratification has not been evaluated according to the "Kidney Disease: Improving Global Outcomes" (KDIGO). AKI was computed according to the KDIGO definition in patients with acute PE in the RIETE (Registro Informatizado Enfermedad TromboEmbolica) registry. Patients with hemodynamic instability were considered high-risk. Normotensive patients were stratified according to the sPESI score (low-risk: sPESI = 0; intermediate-risk: sPESI > 0). The primary outcome was all-cause 30-day mortality. Secondary outcomes were major bleeding and VTE recurrences during the same period. Among 30,532 patients with PE, 1108 (3.6%) were classified to be at high-risk, 10,577 (34.6%) at low-risk, and the remaining 18,847 (61.8%) at intermediate-risk of adverse events. At baseline, 7879 (26%) had AKI. Overall, 1543 of 30,532 patients (5.1%) died within the first 30 days. The presence of AKI was associated with increased mortality rates in all subgroups of patients: in those at low-risk it increased from 0.46 to 3%, in intermediate-risk from 5.4 to 10%, and in high-risk patients from 9.4 to 18%. The presence of AKI was also associated with an increased risk of major bleeding in all subgroups. The addition of the AKI status to the sPESI score improved the prediction of the 30-day mortality and may be particularly helpful for decisions such as identification of low-risk patient for home discharge.

Ventilation/perfusion (V/Q) scanning in contemporary patients with pulmonary embolism: utilization rates and predictors of use in a multinational study.

Ventilation/perfusion (V/Q) imaging and computed tomography pulmonary angiography (CTPA) are common tools for acute pulmonary embolism (PE) diagnosis. Limited contemporary data exist about the utilization of each modality, including the predictors of using V/Q versus CTPA. We used the data from patients diagnosed with PE using V/Q or CTPA from 2007 to 2019 in Registro Informatizado Enfermedad ThromboEmbolica, an international prospective registry of patients with venous thromboembolism. Outcomes was to determine the trends in utilization of V/Q vs. CTPA and, in a contemporary subgroup fitting with current practices, to evaluate predictors of V/Q use with multivariable logistic regression. Among 26,540 patients with PE, 89.2% were diagnosed with CTPA, 7.1% with V/Q and 3.7% with > 1 thoracic imaging modality. Over time, the proportional use of V/Q scanning declined (13.9 to 3.3%, P < 0.001). In multivariable analysis, heart failure history (odds ratio [OR]:1.5; 95% confidence interval [CI] 1.14-1.98), diabetes ([OR 1.71; 95% CI 1.39-2.10]), moderate and severe renal failure (respectively [OR 1.87; 95% CI 1.47-2.38] and [OR 9.36; 95% CI 6.98-12.55]) were the patient-level predictors of V/Q utilization. We also observed an influence of geographical and institutional factors, partly explained by time-limited V/Q availability (less use over weekends) and regional practices. Use of V/Q for the diagnosis of PE decreased over time, but it still has an important role in specific situations with an influence of patient-related, institution-related and logistical factors. Local and regional resources should be evaluated to improve V/Q accessibility than could benefit for this population.

Prognostic Impact of Active Cigarette Smoking on Mortality in Patients with Acute Venous Thromboembolic Events, Findings from Real World Data.

Background and Objectives: The influence of smoking habits on mortality, VTE recurrence, and major bleeding in patients receiving anticoagulant therapy for venous thromboembolism (VTE) has not been consistently evaluated. Materials and Methods: We used data from the RIETE (Registro Enfermedad TromboEmbólica) registry to compare mortality, VTE recurrence, and major bleeding risk in smoking versus non-smoking patients with acute VTE. Results: 50,881 patients (43,426 non-smoking and 7455 smoking patients) were included. After a median follow-up of 8.8 months, 7110 patients died (fatal PE 292 and fatal bleeding 281), 3243 presented VTE recurrence, and 1579 had major bleeding. At multivariate analysis, smoking behavior was associated with a higher hazard of death, (HR: 1.28; 95% CI: 1.19-1.40). The risk of VTE recurrence was marginally increased in smoking patients compared to non-smoking patients (1.14; 95% CI: 1.02-1.27). Major bleeding did not differ in smoking and non-smoking patients (1.15; 95% CI: 0.96-1.38). The presence of cancer did not appear to influence the association between smoking habits and death (HR: 1.34; 95% CI: 1.22-1.47 in cancer patients and HR: 1.23; 95% CI: 1.04, 1.45 in non-cancer patients, respectively) Conclusions: the risk of death after an acute episode of VTE appeared to be higher in smoking than in non-smoking patients and this risk is higher between patients presenting PE at the onset of symptoms.

Risk of recurrent venous thromboembolism in patients with autoimmune diseases: data from the Registro Informatizado de Enfermedad TromboEmbólica (RIETE) registry.

Autoimmune disease is a risk factor for first incident venous thromboembolism (VTE). However, data on the risk of recurrent VTE in people with autoimmune disease is sparse. We explored the risk of recurrent VTE using the RIETE registry, comparing people with autoimmune disease (n = 1305) to those without (n = 50608). Overall rates were 6.5 and 5.1 recurrent VTE/100 years for patients with autoimmune disease vs controls, respectively. After adjustment for sex and unprovoked/provoked VTE yielded an adjusted hazard ratio of 1.29 (95%CI 1.03-1.62). The analysis was limited by short median follow up time (161 days overall), precluding definitive conclusions on recurrent VTE risks.

Clinical characteristics and 3-month outcomes in cancer patients with incidental versus clinically suspected and confirmed pulmonary embolism.

BACKGROUND: Current guidelines suggest treating cancer patients with incidental pulmonary embolism (PE) similarly to those with clinically suspected and confirmed PE. However, the natural history of these presentations has not been thoroughly compared. METHODS: We used the data from the RIETE (Registro Informatizado de Enfermedad TromboEmbólica) registry to compare the 3-month outcomes in patients with active cancer and incidental PE versus those with clinically suspected and confirmed PE. The primary outcome was 90-day all-cause mortality. Secondary outcomes were PE-related mortality, symptomatic PE recurrences and major bleeding. RESULTS: From July 2012 to January 2019, 946 cancer patients with incidental asymptomatic PE and 2274 with clinically suspected and confirmed PE were enrolled. Most patients (95% versus 90%) received low-molecular-weight heparin therapy. During the first 90 days, 598 patients died, including 42 from PE. Patients with incidental PE had a lower all-cause mortality rate than those with suspected and confirmed PE (11% versus 22%; OR 0.43, 95% CI 0.34-0.54). Results were consistent for PE-related mortality (0.3% versus 1.7%; OR 0.18, 95% CI 0.06-0.59). Multivariable analysis confirmed that patients with incidental PE were at lower risk of death (adjusted OR 0.43, 95% CI 0.34-0.56). Overall, 29 (0.9%) patients developed symptomatic PE recurrences, and 122 (3.8%) had major bleeding. There were no significant differences in PE recurrences (OR 0.62, 95% CI 0.25-1.54) or major bleeding (OR 0.78, 95% CI 0.51-1.18). CONCLUSIONS: Cancer patients with incidental PE had a lower mortality rate than those with clinically suspected and confirmed PE. Further studies are required to validate these findings, and to explore optimal management strategies in these patients.

Presenting Characteristics, Treatment Patterns, and Outcomes among Patients with Venous Thromboembolism during Hospitalization for COVID-19.

Venous thromboembolism (VTE) is common in patients with coronavirus disease-2019 (COVID-19). However, limited data exist on patient characteristics, treatments, and outcomes. To describe the clinical characteristics, treatment patterns, and short-term outcomes of patients diagnosed with VTE during hospitalization for COVID-19. This is a prospective multinational study of patients with incident VTE during the course of hospitalization for COVID-19. Data were obtained from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) registry. All-cause mortality, VTE recurrences, and major bleeding during the first 10 days were separately investigated for patients in hospital wards versus those in intensive care units (ICUs). As of May 03, 2020, a total number of 455 patients were diagnosed with VTE (83% pulmonary embolism, 17% isolated deep vein thrombosis) during their hospital stay; 71% were male, the median age was 65 (interquartile range, 55-74) years. Most patients (68%) were hospitalized in medical wards, and 145 in ICUs. Three hundred and seventeen (88%; 95% confidence interval [CI]: 84-91%) patients were receiving thromboprophylaxis at the time of VTE diagnosis. Most patients (88%) received therapeutic low-molecular-weight heparin, and 15 (3.6%) received reperfusion therapies. Among 420 patients with complete 10-day follow-up, 51 (12%; 95% CI: 9.3-15%) died, no patient recurred, and 12 (2.9%; 95% CI: 1.6-4.8%) experienced major bleeding. The 10-day mortality rate was 9.1% (95% CI: 6.1-13%) among patients in hospital wards and 19% (95% CI: 13-26%) among those in ICUs. This study provides characteristics and early outcomes of patients diagnosed with acute VTE during hospitalization for COVID-19. Additional studies are needed to identify the optimal strategies to prevent VTE and to mitigate adverse outcomes associated.