Outcome of patients with different clinical presentations of high-risk pulmonary embolism

Aims

The 2019 European Society of Cardiology (ESC) guidelines provide a revised definition of high-risk pulmonary embolism (PE) encompassing three clinical presentations: Cardiac arrest, obstructive shock, and persistent hypotension. This study investigated the prognostic implications of this new definition.

Methods and results

Data from 784 consecutive PE patients prospectively enrolled in a single-centre registry were analysed. Study outcomes include an in-hospital adverse outcome (PE-related death or cardiopulmonary resuscitation) and in-hospital all-cause mortality. Overall, 86 patients (11.0%) presented with high-risk PE and more often had an adverse outcome (43.0%) compared to intermediate-high-risk patients (6.1%; P < 0.001). Patients with cardiac arrest had the highest rate of an in-hospital adverse outcome (78.4%) and mortality (59.5%; both P < 0.001 compared to intermediate-high-risk patients). Obstructive shock and persistent hypotension had similar rates of adverse outcomes (15.8% and 18.2%, respectively; P = 0.46), but the only obstructive shock was associated with an increased all-cause mortality risk. Use of an optimised venous lactate cut-off value (3.8 mmol/L) to diagnose obstructive shock allowed differentiation of adverse outcome risk between patients with shock (21.4%) and persistent hypotension (9.5%), resulting in a net reclassification improvement (0.24 ± 0.08; P = 0.002).

Conclusion

The revised ESC 2019 guidelines definition of high-risk PE stratifies subgroups at different risk of in-hospital adverse outcomes and all-cause mortality. Risk prediction can be improved by using an optimised venous lactate cut-off value to diagnose obstructive shock, which might help to better assess the risk-to-benefit ratio of systemic thrombolysis in different subgroups of high-risk patients.

Prognostic value of right atrial dilation in patients with pulmonary embolism

Aims

Right atrial (RA) dilation and stretch provide prognostic information in patients with cardiovascular diseases. We investigated the prevalence, confounding factors and prognostic relevance of RA dilation in patients with pulmonary embolism (PE).

Methods

Overall, 609 PE patients were consecutively included in a prospective single-centre registry between September 2008 and August 2017. Volumetric measurements of heart chambers were performed on routine non-electrocardiographic-gated computed tomography and plasma concentrations of mid-regional pro-atrial natriuretic peptide (MR-proANP) measured on admission. An in-hospital adverse outcome was defined as PE-related death, cardiopulmonary resuscitation, mechanical ventilation or catecholamine administration.

Results

Patients with an adverse outcome (11.2%) had larger RA volumes (median 120 (interquartile range 84-152) versus 102 (78-134) mL; p=0.013), RA/left atrial (LA) volume ratios (1.7 (1.2-2.4) versus 1.3 (1.1-1.7); p<0.001) and MR-proANP levels (282 (157-481) versus 129 (64-238) pmol·L^-1; p<0.001) compared to patients with a favourable outcome. Overall, 499 patients (81.9%) had a RA/LA volume ratio ≥1.0 and a calculated cut-off value of 1.8 (area under the curve 0.64, 95% CI 0.56-0.71) predicted an adverse outcome, both in unselected (OR 3.1, 95% CI 1.9-5.2) and normotensive patients (OR 2.7, 95% CI 1.3-5.6). MR-proANP ≥120 pmol·L^-1 was identified as an independent predictor of an adverse outcome, both in unselected (OR 4.6, 95% CI 2.3-9.3) and normotensive patients (OR 5.1, 95% CI 1.5-17.6).

Conclusions

RA dilation is a frequent finding in patients with PE. However, the prognostic performance of RA dilation appears inferior compared to established risk stratification markers. MR-proANP predicted an in-hospital adverse outcome, both in unselected and normotensive PE patients, integrating different prognostic relevant information from comorbidities.

Venous lactate improves the prediction of in-hospital adverse outcomes in normotensive pulmonary embolism

BACKGROUND

Arterial lactate is an established risk marker in patients with pulmonary embolism (PE). However, its clinical applicability is limited by the need of an arterial puncture. In contrast, venous lactate can easily be measured from blood samples obtained via routine peripheral venepuncture.

METHODS

We investigated the prognostic value of venous lactate with regard to in-hospital adverse outcomes and mortality in 419 consecutive PE patients enrolled in a single-center registry between 09/2008 and 09/2017.

RESULTS

An optimised venous lactate cut-off value of 3.3 mmol/l predicted both, in-hospital adverse outcome (OR 11.0 [95% CI 4.6-26.3]) and all-cause mortality (OR 3.8 [95%CI 1.3-11.3]). The established cut-off value for arterial lactate (2.0 mmol/l) and the upper limit of normal for venous lactate (2.3 mmol/l) had lower prognostic value for adverse outcomes (OR 3.6 [95% CI 1.5-8.7] and 5.7 [95% CI 2.4-13.6], respectively) and did not predict mortality. If added to the 2019 European Society of Cardiology (ESC) algorithm, venous lactate <2.3 mmol/l was associated with a high negative predictive value (0.99 [95% CI 0.97-1.00]) for adverse outcomes in intermediate-low-risk patients, whereas levels ≥3.3 mmol/l predicted adverse outcomes in the intermediate-high-risk group (OR 5.2 [95% CI 1.8-15.0]).

CONCLUSION

Venous lactate above the upper limit of normal was associated with increased risk for adverse outcomes and an optimised cut-off value of 3.3 mmol/l predicted adverse outcome and mortality. Adding venous lactate to the 2019 ESC algorithm may improve risk stratification. Importantly, the established cut-off value for arterial lactate has limited specificity in venous samples and should not be used.

Venous lactate predicts adverse outcomes in normotensive pulmonary embolism

Background/Introduction

Arterial lactate is an established risk marker in patients with acute pulmonary embolism (PE). However, its clinical application is limited by the need for an arterial puncture, a procedure not routinely performed in haemodynamically stable PE patients. In contrast, information on venous lactate can be easily obtained via peripheral venepuncture and might thus be more suitable for risk assessment in normotensive PE.

Purpose

To investigate the prognostic value of peripheral venous lactate for outcome prediction in normotensive patients with acute PE.

Methods

Consecutive normotensive PE patients enrolled in a prospective single-centre registry between 09/2008 and 03/2018 were studied. Study outcomes included in-hospital adverse outcome (PE-related death, cardiopulmonary resuscitation or vasopressor treatment) and all-cause mortality. An optimised venous lactate cut-off concentration was identified using receiver operating curve analysis and its prognostic value compared to the established cut-off value for arterial lactate (2.0 mmol/l) and the upper limit of normal for venous lactate (2.3 mmol/l). Furthermore, we tested if addition of venous lactate to the 2019 European Society of Cardiology (ESC) risk stratification algorithm improves risk prediction.

Results

We analysed data from 419 (age 70 [interquartile range (IQR) 57–79] years; 53% female) patients. Patients with an in-hospital adverse outcome had higher venous lactate concentrations than those with a favourable clinical course (3.1 [IQR 1.3–4.9] vs. 1.6 [IQR 1.2–2.3] mmol/l, p=0.001). An optimized cut-off value of 3.3 mmol/l predicted both, adverse outcome (OR 11.0 [95% CI 4.6–26.3]) and all-cause mortality (OR 3.8 [95% CI 1.3–11.3]). Venous lactate ≥2.0 mmol/l and ≥2.3 mmol/l had lower predictive value for an adverse outcome (OR 3.6 [95% CI 1.5–8.7] and OR 5.7 [95% CI 2.4–13.6], respectively) and did not predict all-cause mortality. If venous lactate was added to the 2019 ESC algorithm (Figure), a cut-off concentration of 2.3 mmol/l had high negative predictive value (0.99 [95% CI 0.97–1.00]) for an adverse outcome in intermediate-low-risk patients, whereas levels ≥3.3 mmol/l predicted adverse outcomes in the intermediate-high-risk group (OR 5.2 (95% CI 1.8–15.0).

Conclusions

Even modest venous lactate elevations above the upper limit of normal (2.3 mmol/l) were associated with increased risk for an in-hospital adverse outcome and a cut-off value of 3.3 mmol/l provided optimal prognostic performance predicting both, an adverse outcome and all-cause mortality. Adding venous lactate to the 2019 ESC algorithm seems to further improve risk stratification. Importantly, the established cut-off value for arterial lactate (2.0 mmol/l) has limited specificity in venous samples and should not be used.

Venous lactate for risk stratification

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This study was supported by the German Federal Ministry of Education and Research (BMBF 01EO1503). The authors are responsible for the contents of this publication. BRAHMS GmbH, part of Thermo Fisher Scientific, Hennigsdorf/Berlin, Germany provided financial support for biomarker measurements. The sponsor was neither involved in biomarker measurements, statistical analyses, writing of the abstract nor had any influence on the scientific contents.

Atrial fibrillation is frequent but does not affect risk stratification in pulmonary embolism

BACKGROUND

Although prior studies indicate a high prevalence of atrial fibrillation (AF) in patients with pulmonary embolism (PE), the exact prevalence and prognostic impact are unknown.

METHODS

We aimed to investigate the prevalence, risk factors and prognostic impact of AF on risk stratification, in-hospital adverse outcomes and mortality in 528 consecutive PE patients enrolled in a single-centre registry between 09/2008 and 09/2017.

RESULTS

Overall, 52 patients (9.8%) had known AF and 57 (10.8%) presented with AF on admission; of those, 34 (59.6%) were newly diagnosed with AF. Compared to patients with no AF, overt hyperthyroidism was associated with newly diagnosed AF (OR 7.89 [2.99-20.86]), whilst cardiovascular risk comorbidities were more frequently observed in patients with known AF. Patients with AF on admission had more comorbidities, presented more frequently with tachycardia and elevated cardiac biomarkers and were hence stratified to higher risk classes. However, AF on admission had no impact on in-hospital adverse outcome (8.3%) and in-hospital mortality (4.5%). In multivariate logistic regression analyses corrected for AF on admission, NT-proBNP and troponin elevation as well as higher risk classes in risk assessment models remained independent predictors of an in-hospital adverse outcome.

CONCLUSION

Atrial fibrillation is a frequent finding in PE, affecting more than 10% of patients. However, AF was not associated with a higher risk of in-hospital adverse outcomes and did not affect the prognostic performance of risk assessment strategies. Thus, our data support the use of risk stratification tools for patients with acute PE irrespective of the heart rhythm on admission.

P5021Hypoperfusion markers identify patients with acute pulmonary embolism at highest risk for an adverse outcome

Background/Introduction

According to the European Society of Cardiology (ESC) 2014 guideline, systemic hypotension (HT) is the critical variable defining high-risk in patients with pulmonary embolism (PE). However, signs of organ hypoperfusion might more adequately identify PE patients with cardiogenic shock due to right ventricular (RV) failure.

Purpose

We investigated whether hypoperfusion markers provide superior prognostic information for identifying PE patients at highest risk of early adverse outcomes.

Methods

Consecutive PE patients enrolled in a prospective single-centre registry between 09/2008 and 03/2018 were included. We analysed the predictive value of symptoms and findings suggesting hypoperfusion for in-hospital adverse outcome (catecholamine treatment, resuscitation or PE-related death) and in-hospital all-cause mortality.

Results

We analysed 814 patients, including 83 (10.2%) ESC 2014 high-risk patients. Patients presenting with cardiac arrest (CA, 4.5%) were a priori defined as high risk. Markers suggesting hypoperfusion of the brain (altered metal status, odds ratio [OR] 8.2 [95% CI, 4.2–16.0]), lung (respiratory insufficiency, 25.0 [9.4–66.7]) and tissue (venous lactate ≥2.2 mmol/l, 6.4 [3.2–12.9]) as well as HT (13.5 [6.7–27.2]) predicted an adverse outcome. The risk for an adverse outcome increased with the number of positive markers (AUC 0.86 [0.80–0.93]). Patients with ≥3 positive hypoperfusion markers had an OR of 42.9 (11.0–167.3) and patients defined as high-risk by the ESC 2014 an OR of 17.2 (8.8–33.3) with regard to an adverse outcome (Figure 1; Table 1).

A new definition of high-risk (CA or ≥3 hypoperfusion markers) was associated with an OR of 73.2 (31.3–171.1) for an in-hospital adverse outcome and 26.2 (12.1–56.7) for in-hospital mortality.

Table 1. Prognostic performance of hypoperfusion markers Adverse outcome (if negative) Adverse outcome (if positive) Sensitivity Specificity LR+ OR (95% CI) ≥1 hypoperfusion marker 1.1% 21.0% 91.9% 68.2% 2.9 24.4 (7.3–80.8) ≥2 hypoperfusion markers 4.7% 50.0% 48.6% 95.5% 10.9 20.3 (9.1–45.1) ≥3 hypoperfusion markers 6.5% 75.0% 24.3% 99.3% 32.7 42.9 (11.0–167.3) ESC 2014 high-risk 5.7% 51.1% 35.0% 96.9% 11.4 17.2 (8.8–33.3) Cardiac arrest 8.4% 86.5% 33.0% 99.3% 47.3 70.1 (26.4–186.1) Abbreviations: LR+, positive likelihood ratio; OR, odds ratio; CI, confidence interval.

Figure 1. Frequency of adverse outcome

Conclusions

Markers of organ hypoperfusion have high predictive value for early adverse outcomes in acute PE. Risk increases with the number of positive markers and is critically elevated in patients presenting with CA or ≥3 markers.

Acknowledgement/Funding

This study was supported by the German Federal Ministry of Education and Research (BMBF 01EO1503).