LR-PED rule: low risk pulmonary embolism decision rule - a new decision score for low risk pulmonary embolism

Cardiac Troponins in Low-Risk Pulmonary Embolism Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Patients with low-risk pulmonary embolism (PE) should be considered as per current scoring systems for ambulatory treatment. However, there is uncertainty whether patients with low scores and positive troponins should require hospitalization.

METHODS

We searched MEDLINE, SCOPUS, and Cochrane Library databases from inception to December 2016 and collected longitudinal studies that evaluated the prognostic value of troponins in patients with low-risk PE. The primary outcome measure was 30-day all-cause mortality. We calculated odds ratio (OR), likelihood ratios (LRs), and 95% confidence intervals (CI) by using randomeffects models.

RESULTS

The literature search identified 117 candidate articles, of which 16 met the criteria for review. Based on pulmonary embolism severity index (PESI) or simplified PESI score, 1.2% was the all-cause mortality rate across 2,662 participants identified as low-risk. A positive troponin status in patients with low-risk PE was associated with an increased risk of 30-day all-cause mortality (odds ratio [OR]: 4.79; 95% confidence interval [CI]: 1.11 to 20.68). The pooled likelihood ratios (LRs) for all-cause mortality were positive LR 2.04 (95% CI, 1.53 to 2.72) and negative LR 0.072 (95% CI, 0.37 to 1.40).

CONCLUSIONS

The use of positive troponin status as a predictor of increased mortality in low-risk PE patients exhibited relatively poor performance given the crossed negative LR CI (1.0) and modest positive LR. Larger prospective trials must be conducted to elucidate if patients with low-risk PE and positive troponin status can avoid hospitalization.

Update on the risk stratification of acute symptomatic pulmonary thromboembolism

Early mortality in patients with pulmonary thromboembolism (PTE) varies from 2% in normotensive patients to 30% in patients with cardiogenic shock. The current risk stratification for symptomatic PTE includes 4 patient groups, and the recommended therapeutic strategies are based on this stratification. Patients who have haemodynamic instability are considered at high risk. Fibrinolytic treatment is recommended for these patients. In normotensive patients, risk stratification helps differentiate between those of low risk, intermediate-low risk and intermediate-high risk. There is currently insufficient evidence on the benefit of intensive monitoring and fibrinolytic treatment in patients with intermediate-high risk. For low-risk patients, standard anticoagulation is indicated. Early discharge with outpatient management may be considered, although its benefit has still not been firmly established.

Prognostic models in acute pulmonary embolism: a systematic review and meta-analysis

OBJECTIVE

To review the evidence for existing prognostic models in acute pulmonary embolism (PE) and determine how valid and useful they are for predicting patient outcomes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

OVID MEDLINE and EMBASE, and The Cochrane Library from inception to July 2014, and sources of grey literature.

ELIGIBILITY CRITERIA

Studies aiming at constructing, validating, updating or studying the impact of prognostic models to predict all-cause death, PE-related death or venous thromboembolic events up to a 3-month follow-up in patients with an acute symptomatic PE.

DATA EXTRACTION

Study characteristics and study quality using prognostic criteria. Studies were selected and data extracted by 2 reviewers.

DATA ANALYSIS

Summary estimates (95% CI) for proportion of risk groups and event rates within risk groups, and accuracy.

RESULTS

We included 71 studies (44,298 patients). Among them, 17 were model construction studies specific to PE prognosis. The most validated models were the PE Severity Index (PESI) and its simplified version (sPESI). The overall 30-day mortality rate was 2.3% (1.7% to 2.9%) in the low-risk group and 11.4% (9.9% to 13.1%) in the high-risk group for PESI (9 studies), and 1.5% (0.9% to 2.5%) in the low-risk group and 10.7% (8.8% to12.9%) in the high-risk group for sPESI (11 studies). PESI has proved clinically useful in an impact study. Shifting the cut-off or using novel and updated models specifically developed for normotensive PE improves the ability for identifying patients at lower risk for early death or adverse outcome (0.5-1%) and those at higher risk (up to 20-29% of event rate).

CONCLUSIONS

We provide evidence-based information about the validity and utility of the existing prognostic models in acute PE that may be helpful for identifying patients at low risk. Novel models seem attractive for the high-risk normotensive PE but need to be externally validated then be assessed in impact studies.

Derivation and validation of the In-hospital Mortality for PulmonAry embolism using Claims daTa (IMPACT) prediction rule

INTRODUCTION

Existing prediction rules for prospectively prognosticating early mortality following pulmonary embolism (PE) require clinical and/or laboratory data, and are rarely suitable for claims database analyses. We sought to develop a claims-based prediction rule that retrospectively classifies PE patients into low- or higher-risk in-hospital mortality categories.

MATERIALS AND METHODS

We randomly assigned MarketScan database patient admitted for PE between April 2010 and September 2013 into derivation (80%) and validation (20%) cohorts. A prediction rule (In-hospital Mortality for PulmonAry embolism using Claims daTa or IMPACT) was derived using multivariable logistic regression, with in-hospital mortality as the dependent variable and demographic/comorbidity data available in claims databases as independent variables. In-hospital mortality rates for low- and higher-risk patients were compared across the derivation and validation cohorts, and prediction rule performance was assessed by evaluating sensitivity and specificity estimates.

RESULTS

A total of 27,833 patients admitted for PE were included. The IMPACT rule consisted of 12 risk factors, and categorized 46% of patients as low-risk in both cohorts. Patients classified as low-risk by IMPACT (defined as an estimated in-hospital mortality risk ≤1.5%) had average in-hospital mortality rates of 0.81% (95% confidence interval [CI], 0.65-1.00) in the derivation and 0.77% (95% CI, 0.50-1.18) in the validation cohort. Higher-risk patients had average in-hospital mortality rates of 4.61% (95% CI, 4.25-5.01) and 5.02% (95% CI, 4.30-5.85), respectively. The IMPACT rule had high sensitivity for classifying in-hospital mortality risk (0.87 in both cohorts), but moderate specificity (0.47 for both cohorts).

LIMITATIONS

We were unable to assess 30 day mortality as an endpoint. IMPACT was only validated in an internal sample.

CONCLUSIONS

The IMPACT prediction rule may be able to retrospectively classify PE patients' in-hospital mortality risk with high sensitivity and moderate specificity.

Pulmonary embolism: whom to discharge and whom to thrombolyze?

Patients with pulmonary embolism can be divided in two groups according to their risk of death or major complication: a small group of high-risk patients defined by the presence of systemic hypotension or cardiogenic shock and a large group of normotensive patients. Among normotensive patients, further risk stratification, based on clinical grounds alone or on the combination of clinical data, biomarkers, and imaging tests, allows selection of low-risk patients and intermediate-risk patients. The safety of outpatient treatment for low-risk patients has been established mainly on the basis of retrospective and prospective cohorts using different selection tools. In most studies, about 50% of the patients have been safely treated at home. Although thrombolytic therapy has a favorable benefit to risk profile in patients with high-risk pulmonary embolism, the risk of major and especially intracranial bleeding outweighs the benefits in terms of hemodynamic decompensation in patients with intermediate-risk pulmonary embolism.

Treatment and long-term management of venous thromboembolism

Venous thromboembolism covers a range of conditions from deep vein thrombosis to pulmonary embolism. Treatment aims to alleviate symptoms, minimize acute morbidity and mortality by preventing the extension or potentially fatal embolization of the initial thrombus, and avoid postthrombotic syndrome. Anticoagulant therapy is the mainstay of treatment, but treatment decisions and the choice of an appropriate anticoagulation agent are modified according to the predisposition for venous thromboembolism, the site and extent of thrombus, the presence or absence of symptomatic embolism, and patient's bleeding risk. Newer oral anticoagulants have been developed to overcome the drawbacks of other agents, improve patient care, and simplify and improve management.

Pulmonary embolism in elderly patients: prognostic impact of the Cumulative Illness Rating Scale (CIRS) on short-term mortality

BACKGROUND

Pulmonary embolism (PE) is associated with high short-term mortality in elderly patients, even when hemodynamically stable.

METHODS

One hundred and seventy hemodynamically stable patients with confirmed PE (41<65years and 129≥65years) were prospectively followed for one month in order to assess whether comorbidities can predict short-term mortality in elderly patients. Upon admission, patients' clinical characteristics (including instrumental and laboratory parameters) were evaluated, and two clinical scores were calculated: the Cumulative Illness Rating Scale (CIRS), commonly used to evaluate comorbidities in elderly patients, and the Pulmonary Embolism Severity Index (PESI).

RESULTS

Fifteen patients (all elderly) died within one month from their PE diagnosis (mortality rate=8.8%; 95%CI:4.6-13.1%). In these non survivors, arterial partial oxygen pressure (p<0.0001) and saturation (p<0.0001), pH (p=0.001) and systolic blood pressure (p=0.017) at admission were significantly lower than in survivors, whereas their respiratory rate (p<0.0001), white blood cells (p<0.0001), lactate dehydrogenase (p<0.0001), troponin T (p=0.001) and D-dimer (p=0.023) were significantly higher. CIRS correlated with PESI (rho=0.54, p<0.0001), and was higher in non-survivors (p=0.002). The age- and sex-adjusted odds ratio of 1-month mortality was 1.91 (95%CI:1.24-2.95) for every 1-point increase in CIRS. The AUC was 0.78 (95%CI:0.67-0.89) for the logistic model containing CIRS, and 0.88 (95%CI:0.79-0.96) for that containing PESI (p=0.059).

CONCLUSIONS

In elderly patients with PE, CIRS demonstrated a fairly good performance in predicting short-term mortality. Its easiness and suitability for use in common clinical practice make CIRS a potentially useful prognostic score for short-term mortality in these patients.

A review on state-of-the-art data regarding safe early discharge following admission for pulmonary embolism: what do we know?

BACKGROUND

Although most patients with acute pulmonary embolism (PE) remain hospitalized during initial therapy, some may be suitable for partial or complete outpatient management, which may have a significant impact on healthcare costs.

HYPOTHESIS

This article reviews the state-of-the-art data regarding recognition of very-low-risk PE patients who are potentially eligible for outpatient treatment, along with the safety, management, and cost-effectiveness of this strategy. We propose an algorithm based on collected data that may be useful/practical for identifying patients truly eligible for early discharge.

METHODS

Comprehensive review of scientific data collected from the MEDLINE and Cochrane databases. Studies selected based on potential scientific interest. Qualitative information extracted regarding feasibility, safety, and cost-effectiveness of outpatient treatment, postdischarge management, and selection of truly low-risk patients.

RESULTS

Early discharge of low-risk patients seems feasible, safe, and particularly cost-effective. Several risk scores have been developed and/or tested as prediction tools for the recognition of low-risk individuals: the Pulmonary Embolism Severity Index (PESI), simplified PESI, Hestia criteria, Geneva score, the Low-Risk Pulmonary Embolism Decision rule, and the Global Registry of Acute Cardiac Events, among others. PESI is the most well-validated model, offering the safest approach at the current time, especially when combined with additional parameters such as troponin I, N-terminal prohormone of brain natriuretic peptide, and echocardiographic markers of right-ventricular dysfunction.

CONCLUSIONS

Recognition of truly low-risk patients entitled to early hospital discharge and outpatient treatment is possible with current risk-stratification schemes along with selected prognostic parameters, and it may have a colossal impact on healthcare costs.

Venous thromboembolism management: where do novel anticoagulants fit?

OBJECTIVE

To review novel oral anticoagulant (NOAC) trials in the treatment of venous thromboembolism (VTE) and the possible use of risk-stratification tools to guide their use in practice.

SCOPE

MEDLINE and Cochrane databases were searched to identify relevant journal articles published from January 1982 to February 2013. Additional references were obtained from articles extracted during the database search.

FINDINGS

NOACs have been developed to optimize VTE management and overcome the limitations of heparin and vitamin K antagonists (VKA). The AMPLIFY and EINSTEIN trials of apixaban and rivaroxaban, respectively, investigated single-drug management of VTE, whereas the edoxaban Hokusai-VTE trial and dabigatran RE-COVER and RE-COVER II trials investigated the use of NOACs with a heparin lead-in. The AMPLIFY and Hokusai-VTE trials are ongoing but the EINSTEIN and RE-COVER trials have demonstrated that rivaroxaban and dabigatran, respectively, are non-inferior to parenteral anticoagulants and warfarin in the management of VTE. Differences in study design complicate the application of study results to clinical practice. There are multiple validated DVT protocols that effectively and safely treat patients in outpatient settings. The pulmonary embolism (PE) severity index (PESI), simplified PESI (sPESI), and other prognostic tools have been used to risk stratify patients with PE by estimating mortality risk to guide outpatient eligibility.

CONCLUSIONS

NOACs provide physicians with new therapeutic options in the management of VTE. While heparin and VKAs compose the current standard treatment for VTE, their use will likely disappear as physicians grow comfortable with the adoption of NOACs. As studies have not clearly defined the efficacy of these agents in certain patient populations, further data in special patient populations and risk stratification through the use of VTE severity scores could potentially be adapted to guide anticoagulant management and outpatient treatment eligibility.

Atrial fibrillation in acute pulmonary embolism: prognostic considerations

AIMS

Although it is accepted that atrial fibrillation (AF) may be both the contributing factor and the consequence of pulmonary embolism (PE), data on the prognostic role of AF in patients with acute venous thromboembolism are scarce. Our aim was to study whether AF had a prognostic role in patients with acute PE.

METHODS

Retrospective cohort study involving 270 patients admitted for acute PE. Collected data: past medical history, analytic/gasometric parameters, admission ECG and echocardiogram, thoracic CT angiography. Patients followed for 6 months. An analysis was performed in order to clarify whether history of AF, irrespective of its timing, helps predict intrahospital, 1-month and 6-month all-cause mortality.

RESULTS

Patients with history of AF, irrespective of its timing (n=57, 21.4%), had higher intrahospital (22.8% vs 13.1%, p=0.052, OR 2.07, 95% CI 0.98 to 4.35), 1-month (35.1% vs 16.9%, p=0.001, OR 3.16, 95% CI 1.61 to 6.21) and 6-month (45.6% vs 17.4%, p<0.001, OR 4.67, 95% CI 2.37 to 9.21) death rates. The prognostic power of AF was independent of age, NT-proBNP values, renal function and admission blood pressure and heart rate and additive to mortality prediction ability of simplified PESI (AF: p=0.021, OR 2.31, CI 95% 1.13 to 4.69; simplified PESI: p=0.002, OR 1.47, CI 95% 1.15 to 1.89). The presence of AF at admission added prognostic value to previous history of AF in terms of 1-month and 6-month all-cause mortality prediction, although it did not increase risk for intrahospital mortality.

CONCLUSIONS

The presence of AF, irrespective of its timing, may independently predict mortality in patients with acute PE. These data should be tested and validated in prospective studies using larger cohorts.

Identification of patients with low-risk pulmonary embolism suitable for outpatient treatment using the pulmonary embolism severity index (PESI)

BACKGROUND

There is increasing evidence that outpatient treatment of patients with low-risk stable pulmonary embolism (PE) is safe, effective and potentially reduces costs. It is not clear how many patients presenting to an Irish Emergency Department (ED) are potentially suitable for outpatient management.

AIMS

To identify how many patients presenting to our ED over a 1-year period who were diagnosed with acute PE are potentially suitable for outpatient treatment.

METHODS

A retrospective observational study was conducted over a 1-year period. Clinical notes for patients who had a positive computed tomographic pulmonary angiogram (CTPA) within 24 h of presentation to the ED were examined to risk stratify the patients according to the pulmonary embolism severity index (PESI).

RESULTS

Forty-seven patients who presented to our ED were diagnosed with a PE. Clinical notes were missing for 3 cases, and 44 cases were analysed further. The mean age was 64.3 (±16.8 SD) years and 24 (54.5 %, 95 % CI 40-68.3 %) were males. Six patients (13.6 %, 95 % CI 6.4-26.7 %) had a background of cancer. Fifteen cases (34.1 %, 95 % CI 21.9-48.7 %) were deemed to be low risk as they were categorised as PESI risk class I or II. Our study found that 61/420 (14.5 %, 95 % CI 11.5-18.2) of CTPAs done were positive for PE.

CONCLUSION

This study suggests that a significant percentage of patients diagnosed with acute PE are low risk as per PESI and therefore potentially suitable for outpatient management.