Developments in the management and treatment of pulmonary embolism

Life expectancy in cancer patients with pulmonary thromboembolism: From clinical prognostic biomarkers and paraclinical investigations to therapeutic approaches (Review)

Pulmonary embolisms (PEs) are obstructions of the pulmonary arteries by thrombi, which are emboli and they most frequently originate from the deep venous system of the inferior limbs. Emboli can also come from the inferior vena cava, abdominal and pelvic veins, or the upper body venous system from the right atrium or ventricle of the heart. Thrombi can form in situ inside pulmonary arteries as well. A cancer patient is at a higher risk for thromboembolic phenomena given both the oncological pathological context and also due to the associated medical or surgical treatment they receive. PE is a high-risk medical emergency that is associated with an increased risk of early mortality, with sudden death occurring in 25% of patients. The long-term presence of this condition can result in thromboembolic pulmonary hypertension. The risk of mortality, both in the acute and long-term, is dependent on the severity of the acute form, the recurrence of the embolism and the associated conditions. The majority of deaths associated with PE can be prevented by early diagnosis. The aim of the present review was to describe the various biological and cellular parameters, together with known paraclinical investigations, to assist in the rapid diagnosis of PE. Mortality in patients with PE and neoplastic conditions may be reduced by initiating anticoagulant treatment as soon as possible. PE may be the first manifestation of an underlying silent malignancy or may represent a complication of an already diagnosed malignancy. Exclusion or confirmation of the diagnosis is of utmost importance to avoid unnecessary anticoagulant treatment associated with a high risk of bleeding or to start immediate anticoagulant treatment if required.

Prevalence of Hemorrhagic Complications in Hospitalized Patients with Pulmonary Embolism

Background: The prevalence of anticoagulant therapy-associated hemorrhagic complications in hospitalized patients with pulmonary embolism (PE) has been scarcely investigated. Aim: To evaluate the prevalence of hemorrhages in hospitalized PE patients. Methods: The Information System “ASKLIPIOS™ HOSPITAL” implemented in the Respiratory Medicine Department, University of Thessaly, was used to collect demographic, clinical and outcome data from January 2013 to April 2021. Results: 326 patients were included. Males outnumbered females. The population’s mean age was 68.7 ± 17.0 years. The majority received low molecular weight heparin (LMWH). Only 5% received direct oral anticoagulants. 15% of the population were complicated with hemorrhage, of whom 18.4% experienced a major event. Major hemorrhages were fewer than minor (29.8% vs. 70.2%, p = 0.001). Nadroparin related to 83.3% of the major events. Hematuria was the most common hemorrhagic event. 22% of patients with major events received a transfusion, and 11% were admitted to intensive care unit (ICU). The events lasted for 3 ± 2 days. No death was recorded. Conclusions: 1/5 of the patients hospitalized for PE complicated with hemorrhage without a fatal outcome. The hemorrhages were mainly minor and lasted for 3 ± 2 days. Among LMWHs, nadroparin was related to a higher percentage of hemorrhages.

Epidemiological study about the mental state of patients after a pulmonary embolism or deep venous thrombosis event

Venous thromboembolism (VTE) occurs frequently and represents a serious threat to patient health. However, its effects on mental health have not been studied sufficiently. The objective of this study was to investigate whether VTE alters the patients' mental state. We gathered questionnaire data on 100 patients (59 men, 41 women; age ranging from 24 to 85 years) concerning psychological symptoms and body image. Our results show that after a VTE, patients develop psychological symptoms, some of which persist for more than 2 years. Examples of those symptoms include depression, intrusion, and increased scrutiny of the body. Intrusion (flashbacks, nightmares, and other traumatic sensations of reliving the thrombotic event) affected 69% of patients and may lead to social isolation, occasionally including loss of employment. Depression affected more than 50% of patients. Productivity typically decreases, and body functionality and feeling of health changed in 34-76% of patients. However, anxiety, disordered impulse control, and maladjustment were less frequent (40% or less), and patients' emotional attitude to their bodies (liking their bodies or being angry with their bodies, feelings of shame and attractiveness) tended not to change over time. Nevertheless, we feel it may be advisable to identify patients with relevant psychological changes after VTE by means of a short evidence-based questionnaire and to offer them psychological treatment in order to improve management and quality of life of these patients. The goal is, therefore, to develop diagnostic and therapeutic recommendations.

Current Endovascular Treatment Options in Acute Pulmonary Embolism

Acute pulmonary embolism (PE) is a significant cause of mortality and morbidity across the globe. Over the last few decades, there have been major therapeutic advances in acute PE management, including catheter-based therapy. However, the effectiveness of catheter-based therapy in acute PE is not supported by Level I evidence, making the use of this promising treatment rather controversial and ambiguous. In this paper, we discuss the risk stratification of acute PE and review the medical and endovascular treatment options. We also summarize and review the data supporting the use of endovascular treatment options in acute PE and describe the potential role of the PE response team.

Technical efficiency, short-term clinical results and safety of a large-bore aspiration catheter in acute pulmonary embolism - A retrospective case study

BACKGROUND

Mechanical thrombectomy plays an important role in the management of acute pulmonary embolism (PE), either when rapid clot dissolution is needed or when thrombolytics are contraindicated. We describe our clinical and technical experience with the FlowTriever mechanical thrombectomy device in patients with acute PE.

MATERIALS AND METHODS

A retrospective analysis was performed on all cases of acute PE treated with the FlowTriever device at a single tertiary care hospital system during the trial period (November 2019-January 2020). Technical and clinical results, including complications, are reported.

RESULTS

Technical success was achieved in all eight successive cases (seven cases of submassive and 1 case of massive PE). Mean pulmonary artery pressure (MPAP) improved significantly after mechanical thrombectomy (27.8 ± 6.4 mmHg preprocedure; 20.5 ± 3.8 mmHg postprocedure; 7.3 ± 5.2 mmHg decrease after the procedure; P = 0.016). Hemoglobin levels did not change significantly after mechanical thrombectomy (11.8 g/dl ± 3.4 preprocedure; 9.9 g/dl ± 2.1 postprocedure; P = 0.20). Reduction in MPAP was achieved in 88% of cases (7/8) and hypoxia improved in all the nonintubated patients (7/7). Mortality observed in one patient with a massive central PE, was not related to the procedure. No mortality or procedural complications were observed in patients with submassive PE.

CONCLUSIONS

The positive initial clinical experience and safety profile using the FlowTriever in the treatment of acute PE suggests, it has the potential to fill the unmet needs of a good mechanical thrombectomy device to treat massive and submassive high-risk PE especially when thrombolytics are contraindicated.

Local Thrombolysis in High-Risk Pulmonary Embolism-13 Years Single-Center Experience

To evaluate the prognosis after local thrombolysis compared to systemic thrombolysis in high-risk pulmonary embolism. Observational study during 13 years which included 37 patients with high-risk pulmonary embolism treated with local thrombolysis and 36 patients with systemic thrombolysis (streptokinase, 250 000 UI/30 minutes followed by 100 000 UI/h). Cardiogenic shock has totally remitted in the group with local thrombolysis (P = .002). The decrease in pressure gradient between right ventricle and right atrium was comparable in both groups in the acute period (the results being influenced by the higher in-hospital mortality after systemic thrombolysis), but significantly better in the next 24 months follow-up after in situ thrombolysis. Major and minor bleeding did not have significant differences. In hospital, mortality was significantly lower in the group with local thrombolysis (P = .003), but for the next 24 months follow-up, the survival was comparable in both groups. Local thrombolysis, during the hospitalization, was associated with lower mortality rate comparing with systemic thrombolysis. In the next 24 months follow-up, the evolution of residual pulmonary hypertension was significantly better after in situ thrombolysis.

Treatment of the acute severe pulmonary embolism using endovascular methods

Purpose

To present a single-centre experience with endovascular treatment of patients with severe symptoms secondary to acute pulmonary embolism (PE).

Material and methods

Twenty-five patients were treated due to contraindications or deficient effects of systemic thrombolytic therapy. The patients were treated with a combination of fragmentation and aspiration, only aspiration, or only fragmentation, and with catheter-directed thrombolytic therapy.

Results

The saturation was improved following treatment in all patients, except in one where the procedure could not be completed. There were no immediate or late procedure-related complications.

Conclusions

Endovascular treatment of severe PE is a safe and efficient option in patients with failing effect or contraindication to systemic thrombolysis.

Health risk stratification based on computed tomography pulmonary artery obstruction index for acute pulmonary embolism

Early effective identification of high-risk patients for acute pulmonary embolism (APE) contributes to timely treatment. The pulmonary artery obstruction index (PAOI) in computed tomography angiography (CTA) is a semi-quantitative observation index, commonly used to evaluate the severity of a patient's condition. This study explores the ability of PAOI to assess the risk stratification of APE. Thirty patients with APE were analysed. They were classified according to the guidelines, and the PAOI and cardiovascular parameters were measured in CTA. The difference of PAOI between different risk stratification patients was compared, and the predictive value of the PAOI for high-risk stratification was evaluated by the receiver operating characteristic curve. The correlation between PAOI and cardiovascular parameters was also analysed by Spearman correlation analysis. The PAOI in low- and high-risk patients was (33.2 ± 18.6)% and (68.1 ± 11.8)% respectively, and the difference was statistically significant. The PAOI was strongly predictive for high-risk patients. The cut-off value was 52.5%, with a sensitivity of 100% and specificity of 81.0%. The PAOI was correlated with the main cardiovascular parameters. We conclude that the PAOI in CTA is helpful for assessing risk stratification in patients with APE, which contributes to the selection of both the treatment plan and prognostic evaluation.

Effect of simvastatin on the SIRT2/NF-κB pathway in rats with acute pulmonary embolism

CONTEXT

Statins have been widely used in acute pulmonary embolism (APE), while simvastatin has been well-established for the prevention of pulmonary hypertension, which was supposed to be an attractive recommendation for APE treatment.

OBJECTIVE

The current article studies the effect of simvastatin on the SIRT2/NF-κB pathway in rats with APE.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into four groups (n = 24 per group): control group, rats were treated with saline once daily for 14 days before administration of saline (sham group) or a suspension of autologous emboli (APE group), or rats were treated with simvastatin (10 mg/kg) for 14 days before administration of autologous emboli (APE + simvastatin) group. The RVSP, mPAP and the arterial blood gas was analyzed. Besides, plasma inflammatory cytokines and MMPs levels, as well as the expression of SIRT2/NF-κB pathway were determined.

RESULTS

Compared with the control and sham groups, the levels of mPAP (31.06 ± 3.47 mmHg), RVSP (35.12 ± 6.02 mmHg), A-aDO₂ (33.14 ± 6.16 mmHg) and MMP-9 (6.89 ± 0.84 ng/mL) activity were significantly elevated, but PaO₂ (66.87 ± 7.85 mmHg) was highly decreased in rats from APE group at 24 h after APE. Meanwhile, the inflammatory changes were aggravated by the enhanced levels of TNF-α (138.85 ± 22.69 pg/mL), IL-1β (128.47 ± 22.14 pg/mL), IL-6 (103.16 ± 13.58 pg/mL) and IL-8 (179.28 ± 25.79 pg/mL), as well as increased NF-κB (5.29 ± 0.47 fold), but reduced SIRT2 (59 ± 6% reduction), and eNOS (61 ± 5% reduction) mRNA in APE rats. APE rats treated with simvastatin led to a significant opposite trend of the above indexes.

CONCLUSIONS

Simvastatin protects against APE-induced pulmonary artery pressure, hypoxemia and inflammatory changes probably due to the regulation of SIRT2/NF-κB signalling pathway, which suggest that simvastatin may have promising protective effects in patients with APE.

Thrombolysis Followed by Apixaban for Massive Pulmonary Embolism and Free-floating Thrombus in Right Ventricle in a Patient with Breast Cancer

Free-floating thrombus in the right ventricle, associated with a massive acute pulmonary embolism (PE), is a rare phenomenon. PE is an important clinical entity with considerable mortality despite advances in diagnosis and treatment. The prognosis of PE depends on right ventricular dysfunction, myocardial injury markers, and early treatment. In this report, we present the case of a 71-year-old woman with a history of breast cancer admitted to intensive care unit for PE complicated by syncope. Although our case may seem complex because it is not represented in the guidelines, the result was satisfactory and showed how treatment with new anticoagulants (in this case apixaban) after massive thrombolysis of PE could be considered and included in the new guidelines.

Pulmonary embolism and in situ pulmonary artery thrombosis in paediatrics

Data on paediatric pulmonary embolism (PE) are scarce. We sought to systematically review the current literature on childhood PE and conducted a search on paediatric PE via PubMed (1946–2013) and Embase (1980–2013). There was significant heterogeneity in reported data. Two patterns were noted: classic thromboembolic PE (TE-PE) and in situ pulmonary artery thrombosis (ISPAT). Mean age of presentation for TE-PE was 14.86 years, and 51% of cases were males. The commonest method for diagnosis of TE-PE was contrast CT with angiography (74% of patients). The diagnosis of TE-PE was often delayed. Although 85% of children with TE-PE had an elevated D-dimer at presentation, it was non-discriminatory for the diagnosis. In paediatric TE-PE, the prevalence of central venous catheters was 23%, immobilisation 38%, systemic infection 31% and obesity 13%, elevated Factor VIII or von Willebrand factor levels 27%, Protein C deficiency 17%, Factor V Leiden 14% and Protein S deficiency 7%. In patients with TE-PE, pharmacologic thrombolysis was used in 29%; unfractionated heparin was the most common initial anticoagulant treatment in 64% and low-molecular-weight heparins the most common follow-up treatment in 83%. Duration of anticoagulant therapy was variable and death was reported in 26% of TE-PE patients. In contrast to TE-PE, patients with ISPAT were not investigated systematically for presence of thrombophilia, had more surgical interventions as the initial management and were often treated with anti-platelet medications. This review summarises important data and identifies gaps in the knowledge of paediatric PE, which may help to design future studies.

Predictive Value of Mean Platelet Volume for Pulmonary Embolism Recurrence

PURPOSE

Recurrence is a major clinical problem in patients with pulmonary embolism and can affect mortality. The decision to discontinue treatment is important for recurrence and is based on patients' clinical features as well as certain blood parameters. Our aim in this study was to evaluate whether mean platelet volume (MPV) and platelet distribution width (PDW) have utility as new predictive parameters for recurrence and mortality in pulmonary embolism.

MATERIALS AND METHODS

A total of 440 patients with pulmonary embolism underwent computed tomography, Doppler ultrasonography, and echocardiography before and at the conclusion of treatment. Thrombocyte count, MPV, PDW, and D-dimer parameters were also evaluated at the same time points.

RESULTS

MPV and PDW were significantly higher in deceased patients (8.8 ± 1.2 fl and 17.4 ± 0.8) compared to surviving patients (7.7 ± 0.9 fl and 17 ± 0.9) (p < 0.0001). Initial MPV and PDW were also significantly higher in patients with recurrence (8.4 ± 0.7 vs 7.6 ± 0.8 fl, p < 0.0001 and 17.3 ± 0.8 vs 16.9 ± 0.9, p = 0.002, respectively) than in patients without recurrence. At the end of treatment, MPV was still higher in patients with recurrence compared to patients without recurrence (8.7 ± 0.5 and 7.5 ± 0.7 fl, respectively, p < 0.0001). MPV values over 8.05 fl at the end of treatment predicted recurrence with 91% sensitivity and 77% specificity.

CONCLUSION

MPV seems to be an indicator of recurrence in pulmonary embolism and may have utility in the prediction of recurrence. Elevated MPV can also be used to predict mortality in pulmonary embolism.

A new prognostic strategy for adult patients with acute pulmonary embolism eligible for outpatient therapy

We sought to derive a parsimonious predictive model to identify a subgroup of patients that will experience a low number of adverse events within 14 days of the diagnosis of pulmonary embolism. Retrospective cohort study of adult patients with acute pulmonary embolism at the Ottawa Hospital between 2007 and 2012. Primary outcome was defined as the composite of all-cause mortality, recurrent venous thromboembolism and major bleeding within 14 days. Multivariate logistic regression models were fit to model the occurrence of the primary outcome so as to guide either outpatient therapy or early discharge after initial admission. Calibration and discrimination were assessed in both the derivation and internal validation cohorts. 1143 patients were included, of whom 42% were treated as outpatients. At pulmonary embolism diagnosis, final score to predict the primary outcome included age, malignancy, intravenous drug or oxygen requirement and systolic blood pressure <90 mmHg, with an area under the curve (AUC) of 0.79 (95% CI 0.73-0.84) and 0.82 (95% CI 0.75-0.89) in the derivation and validation cohorts respectively. Conversely, final score to predict primary outcome after initial admission included age, malignancy, intravenous drug requirement and systolic blood pressure <90 mmHg (AUC: 0.70 (95% CI 0.64-0.76) and 0.72 (95% CI 0.66-0.79) in the derivation and validation cohorts). We have developed two simple clinical scores that may identify patients with pulmonary embolism at low risk of clinically meaningful outcomes during the first 14 days of follow up.

HR+, HER2- Advanced Breast Cancer and CDK4/6 Inhibitors: Mode of Action, Clinical Activity, and Safety Profiles

BACKGROUND

Cyclin-dependent kinase (CDK) 4/6 inhibitor-based therapies have shown great promise in improving clinical outcomes for patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer.

OBJECTIVES

1. Discuss the mode of action of the three CDK4/6 inhibitors in late clinical development: palbociclib (PD-0332991; Pfizer), ribociclib (LEE011; Novartis), and abemaciclib (LY2835219; Lilly). 2. Describe the efficacy and safety data relating to their use in HR+, HER2- advanced breast cancer. 3. Discuss the key side effects associated with CDK4/6 inhibitors along with considerations for adverse event management and patient monitoring.

METHOD

Relevant information and data were assimilated from manuscripts, congress publications, and online sources.

RESULTS

CDK4/6 inhibitors have demonstrated improved progression-free survival in combination with endocrine therapy compared with endocrine therapy alone. The side-effect profile of each agent is described, along with implications for patient monitoring, and considerations for patient care providers and pharmacists.

CONCLUSION

Addition of a CDK4/6 inhibitor to endocrine therapy increases efficacy and delays disease progression. Insight into the unique side-effect profiles of this class of agents and effective patient monitoring will facilitate the successful use of CDK4/6 inhibitor-based therapies in the clinic.

Prothrombotic Fibrin Clot Phenotype Is Associated With Recurrent Pulmonary Embolism After Discontinuation of Anticoagulant Therapy

OBJECTIVE

Pulmonary embolism (PE) is a life-threatening manifestation of venous thromboembolism with a high recurrence rate after anticoagulation cessation. Recently, we have reported that prothrombotic clot phenotype in venous thromboembolism patients is associated with an increased risk of recurrent deep-vein thrombosis.

APPROACH AND RESULTS

We tested whether abnormal clot properties are predictive of recurrent PE. We investigated 156 consecutive white patients aged 18 to 65 years after the first-ever provoked or unprovoked PE (n=89), with or without deep-vein thrombosis. Plasma fibrin clot permeability (K_s), turbidity measurements, calibrated automated thrombography, and efficiency of fibrinolysis using clot lysis time, maximum D-dimer levels, and rate of increase in D-dimer levels were evaluated at ≥3 months of anticoagulant therapy, at least 4 weeks since the anticoagulation withdrawal. The primary end point was recurrent PE during a median follow-up of 50 months. Recurrent PE was diagnosed in 23 (14.7%; 5%/yr) patients. Recurrent PE was associated with formation of denser fibrin networks reflected by lower K_s (P=0.007) and impaired fibrinolysis, as evidenced by prolonged clot lysis time (P=0.012) and reduced maximum rate of increase in D-dimer levels in the lysis assay (P=0.004). Patients with recurrent PE had higher plasma D-dimer (P<0.001) and thrombin peak (P=0.007) compared with the remainder, whereas turbidity measurements and maximum D-dimer levels did not differ in the recurrence. Multivariate model showed that independent predictors of recurrent PE were female sex, unprovoked venous thromboembolism, higher plasma D-dimer, reduced K_s, and reduced maximum rate of increase in D-dimer levels in the lysis assay (all P<0.05).

CONCLUSIONS

Altered fibrin clot properties including formation of more compact clots displaying impaired susceptibility to lysis may predispose to recurrent PE.

Is Routine Thromboprophylaxis Needed in Korean Patients Undergoing Unicompartmental Knee Arthroplasty?

This study was undertaken to determine the prevalence and the natural course of venous thromboembolism (VTE) without thromboprophylaxis to ascertain whether routine thromboprophylaxis is necessary following unicompartmental knee arthroplasty (UKA) in Korean patients. The medical records and multidetector row computed tomography (MDCT) imaging of the consecutive 77 UKAs in 70 patients were reviewed. In all patients, MDCTs were undertaken preoperatively and at 1-week after surgery, and VTE symptoms were evaluated. At postoperative 6-months, follow-up MDCTs were undertaken in all patients in whom VTEs were newly detected after surgery. VTE lesions were newly detected in 18 (26%) of the 70 patients. However, none of the patients complained of VTE-related symptoms and MDCT demonstrated that all VTEs were small and involved limited portion without lower leg edema or pleuroparenchymal complication. At the 6-month follow up MDCT, all types of VTEs were shown to be completely resolved, regardless of their location. All of the VTE lesions maintained an asymptomatic status for 6-month after surgery. VTE following UKA in Korean patients who do not receive thromboprophylaxis seems to occur frequently, but all of the VTEs are clinically insignificant and all VTEs are spontaneously regressed. Routine thromboprophylaxis or thrombolytic treatment in Korean patients undergoing UKA may not be necessary.