Predictive value of high-sensitivity troponin I and D-dimer assays for adverse outcome in patients with acute pulmonary embolism

Effect of transitioning from conventional cardiac troponin to high-sensitivity cardiac troponin on resource utilization- a single center experience

BACKGROUND

Compared to conventional cardiac troponin (cTn), the high-sensitivity cardiac troponin (hs-cTn) assay is associated with improved detection of myocardial infarction (MI).

METHODS

We performed a descriptive retrospective analysis of resource utilization at Rush University Medical Center over the transition period (July 1, 2021) from a cTn to a hs-cTn assay. Inclusion criteria included emergency department (ED) encounters between January 1 to December 31, 2021, with chief complaints of "chest pain" or "dyspnea" with associated troponin orders. The primary endpoint was the percentage of ED discharges. Secondary endpoints included the number of cardiac studies ordered. Univariable comparisons of these endpoints were performed using Student's t-test for continuous variables and Chi-square tests for binary/categorical variables.

RESULTS

A total of 5113 encounters were analyzed. Hs-cTn was associated with an overall increase in ED patient discharges with negative troponin tests (44.1% vs. 29.9%, P < 0.01). In terms of cardiac testing per encounter, hs-cTn was associated with significant increases in the number of troponin tests (1.9 vs. 1.6, P < 0.01), electrocardiograms (3.0 vs. 2.9, P = 0.01), and echocardiograms (0.5 vs. 0.4, P < 0.01). There was a significant decrease in the utilization of stress testing (0.21 vs. 0.26, P < 0.01). There was a significant increase in total coronary angiography use during the hs-cTn period compared to cTn (227/2471 (9.2%) vs. 195/2642 (7.4%), P = 0.02).

CONCLUSION

Transitioning from cTn to hs-cTn was associated with significantly increased ED discharges and an increase in troponin tests, ECG, echocardiograms, and coronary angiograms. There was a decrease in the number of stress tests.

Optimizing Use of High-Sensitivity Troponin for Risk-Stratification of Acute Pulmonary Embolism

BACKGROUND

 High-sensitivity troponin T (HS-TnT) may improve risk-stratification in hemodynamically stable acute pulmonary embolism (PE), but an optimal strategy for combining this biomarker with clinical risk-stratification tools has not been determined.

STUDY HYPOTHESIS

 We hypothesized that different HS-TnT cutoff values may be optimal for identifying (1) low-risk patients who may be eligible for outpatient management and (2) patients at increased risk of clinical deterioration who might benefit from advanced PE therapies.

METHODS

 Retrospective analysis of hemodynamically stable patients in the University of Michigan acute ED-PE registry with available HS-TnT values. Primary and secondary outcomes were 30-day mortality and need for intensive care unit-level care. Receiver operating characteristic curves were used to determine optimal HS-TnT cutoffs in the entire cohort, and for those at higher risk based on the simplified Pulmonary Embolism Severity Index (PESI) or imaging findings.

RESULTS

 The optimal HS-TnT cutoff in the full cohort, 12 pg/mL, was significantly associated with 30-day mortality (odds ratio [OR]: 3.94, 95% confidence interval [CI]: 1.48-10.50) and remained a significant predictor after adjusting for the simplified PESI (sPESI) score and serum creatinine (adjusted OR: 3.05, 95% CI: 1.11-8.38). A HS-TnT cutoff of 87 pg/mL was associated with 30-day mortality (OR: 5.01, 95% CI: 2.08-12.06) in patients with sPESI ≥1 or right ventricular dysfunction.

CONCLUSION

 In this retrospective, single-center study of acute PE patients, we identified distinct optimal HS-TnT values for different clinical uses-a lower cutoff, which identified low-risk patients even in the absence of other risk-stratification methods, and a higher cutoff, which was strongly associated with adverse outcomes in patients at increased risk.

The Prognostic Value of the Serum Levels of Brain Natriuretic Peptide, Troponin I, and D-Dimer, in Addition to the Neutrophil-to-Lymphocyte Ratio, for the Disease Evaluation of Patients with Acute Pulmonary Embolism

Objective

The present study aims to investigate whether the serum levels of brain natriuretic peptide (BNP), troponin I (TnI), and D-dimer, in addition to the neutrophil-to-lymphocyte ratio (NLR), can be used to determine the prognosis of patients with acute pulmonary embolism (APE).

Methods

Data were collected from 72 patients that were diagnosed with APE in our hospital from January 2015 to December 2018. These patients were divided into three groups: a high-risk group (n = 10), a moderate-risk group (n = 33), and a low-risk group (n = 29). The serum levels of BNP, TnI, and D-dimer were determined, and the NLR was measured. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of the single and combined detection of BNP, TnI, and D-dimer, and the NLR was used to determine the prognosis of patients with APE.

Results

The serum levels of BNP, TnI, and D-dimer were significantly higher in the high-risk group than they were in the moderate-risk and low-risk groups (P < 0.05). The serum levels of BNP, TnI, and D-dimer were also significantly higher in the moderate-risk group than they were in the low-risk group (P < 0.05). The serum levels of BNP, TnI, and D-dimer, as well as the NLR, were all significantly higher in the death group than they were in the survival group (P < 0.05). For the combined detection of the four indices, the area under the ROC curve was 0.92, the sensitivity was 0.889, and the specificity was 0.904; each of these values was higher than the corresponding values of single detection.

Conclusion

In patients with APE, higher serum levels of BNP, TnI, D-dimer and NLR are associated with a higher risk stratification, greater severity of disease, and an increased risk of death.

High-sensitivity troponin I for risk stratification in normotensive pulmonary embolism

While numerous studies have confirmed the prognostic role of high-sensitivity troponin T (hsTnT) in pulmonary embolism (PE), high-sensitivity troponin I (hsTnI) is inappropriately studied. This study aimed to investigate the prognostic relevance of hsTnI in normotensive PE, establish the optimal cut-off value for risk stratification and to compare the prognostic performances of hsTnI and hsTnT.

Based on data from 459 consecutive PE patients enrolled in a single-centre registry, receiver operating characteristic analysis was used to identify an optimal hsTnI cut-off value for prediction of in-hospital adverse outcomes (PE-related death, cardiopulmonary resuscitation or vasopressor treatment) and all-cause mortality.

Patients who suffered an in-hospital adverse outcome (4.8%) had higher hsTnI concentrations compared with those with a favourable clinical course (57 (interquartile range (IQR) 22–197) versus 15 (IQR 10–86) pg·mL⁻¹, p=0.03). A hsTnI cut-off value of 16 ng·mL⁻¹ provided optimal prognostic performance and predicted in-hospital adverse outcomes (OR 6.5, 95% CI 1.9–22.4) and all-cause mortality (OR 3.7, 95% CI 1.0–13.3). Between female and male patients, no relevant differences in hsTnI concentrations (17 (IQR 10–97) versus 17 (IQR 10–92) pg·mL⁻¹, p=0.79) or optimised cut-off values were observed. Risk stratification according to the 2019 European Society of Cardiology algorithm revealed no differences if calculated based on either hsTnI or hsTnT (p=0.68).

Our findings confirm the prognostic role of hsTnI in normotensive PE. HsTnI concentrations >16 pg·mL⁻¹ predicted in-hospital adverse outcome and all-cause mortality; sex-specific cut-off values do not seem necessary. Importantly, our results suggest that hsTnI and hsTnT can be used interchangeably for risk stratification.

The study confirms the prognostic relevance of high-sensitivity troponin I in normotensive pulmonary embolism. A cut-off value of 16 pg·mL⁻¹ can be used for risk stratification in male and female patients; sex-specific adjustments do not appear necessary.https://bit.ly/3lCECip

High sensitivity troponins in contemporary cardiology practice: are we turning a corner?

INTRODUCTION

Troponin is considered to be the gold standard biomarker for ruling out MI. There has been a drive to improve the diagnostic speed, and as such the high sensitivity cardiac troponin (hs-cTn) assays have been introduced into clinical practice and are now part of international guidelines. Their novel value in clinical practice more generally is becoming apparent. Areas covered: In this review we will evaluate the evidence for the use of hs-cTn assays in clinical practice, the issues with the assay and how the hs-cTn can be utilized in the future as a biomarker of cardiovascular risk. Expert commentary: The use of the hs-cTn assays as a 'rule out' test for MI is compelling, as a 'rule in' there are significant issues relating the specificity of the assay for MI. The future of the assay may lie in population screening and risk modeling.

Fibrin and D-dimer bind to monomeric GPVI

Fibrin has recently been shown to activate platelets through the immunoglobulin receptor glycoprotein VI (GPVI). In the present study, we show that spreading of human platelets on fibrin is abolished in patients deficient in GPVI, confirming that fibrin activates human platelets through the immunoglobulin receptor. Using a series of proteolytic fragments, we show that D-dimer, but not the E fragment of fibrin, binds to GPVI and that immobilized D-dimer induces platelet spreading through activation of Src and Syk tyrosine kinases. In contrast, when platelets are activated in suspension, soluble D-dimer inhibits platelet aggregation induced by fibrin and collagen, but not by a collagen-related peptide composed of a repeat GPO sequence or by thrombin. Using surface plasmon resonance, we demonstrate that fibrin binds selectively to monomeric GPVI with a K_D of 302 nM, in contrast to collagen, which binds primarily to dimeric GPVI. These results establish GPVI as the major signaling receptor for fibrin in human platelets and provide evidence that fibrin binds to a distinct configuration of GPVI. This indicates that it may be possible to develop agents that selectively block the interaction of fibrin but not collagen with the immunoglobulin receptor. Such agents are required to establish whether selective targeting of either interaction has the potential to lead to development of an antithrombotic agent with a reduced effect on bleeding relative to current antiplatelet drugs.

Postoperative Acute Pulmonary Embolism Following Pulmonary Resections

Postoperative acute pulmonary embolism after pulmonary resections is highly fatal complication. Many literatures have documented cancer to be the highest risk factor for acute pulmonary embolism after pulmonary resections. Early diagnosis of acute pulmonary embolism is highly recommended and computed tomographic pulmonary angiography is the gold standard in diagnosis of acute pulmonary embolism. Anticoagulants and thrombolytic therapy have shown a great success in treatment of acute pulmonary embolism. Surgical therapies (embolectomy and inferior vena cava filter replacement) proved to be lifesaving but many literatures favored medical therapy as the first choice. Prophylaxis pre and post operation is highly recommended, because there were statistical significant results in different studies which supported the use of prophylaxis in prevention of acute pulmonary embolism. Having reviewed satisfactory number of literatures, it is suggested that thoroughly preoperative assessment of patient conditions, determining their risk factors complicating to pulmonary embolism and the use of appropriate prophylaxis measures are the key options to the successful minimization or eradication of acute pulmonary embolism after lung resections.

Predictors of early death in patients with acute pulmonary embolism

AIM

We aimed to determine the predictors of early death in the course of acute pulmonary embolism (APE).

MATERIALS AND METHODS

We included 206 patients who had been admitted to our hospital between January 2011 and April 2013 with the diagnosis of APE. We derived a new model including corrected QT interval dispersion (QTcd) and P wave dispersion (Pd), echocardiographic findings, laboratory markers, and blood cell count indices to predict early death in patients with APE.

RESULTS

Thirty patients (14.5%) died; 176 patients (85.5%) lived after diagnosis of APE. Logistic regression (LR) analysis found that troponin I (odds ratio [OR], 1.084 [95% confidence interval {CI}, 1.009-1.165]), creatinine (OR, 4.153 [95% CI, 1.375-12.541]), mean platelet volume (OR, 1.991 [95% CI, 1.230-3.223]), neutrophil to lymphocyte ratio (NLR) (OR, 1.079 [95% CI, 1.005-1.160]), QTcd (OR, 1.084 [95% CI, 1.043-1.127]), Pd (OR, 1.049 [95% CI, 1.004-1.096]) were associated with early death in APE. New LR model (area under the curve [AUC], 0.970) performed better than the simplified pulmonary embolism severity index (sPESI) score (AUC, 0.859) in predicting early death in APE (P=.021). The predictivity of the sPESI score significantly improved after its single combination with creatinine, QTcd, or troponin I. When the combined model was constructed together with these 6 independent variables and sPESI score, stepwise LR model automatically excluded Pd and NLR, and the AUC from the rest of the combined model was 0.976, which is significantly different from the AUC of sPESI (0.859) (P=.0031).

CONCLUSIONS

Creatinine, troponin I, and QTcd significantly improves sPESI score. A new model with troponin I, creatinine, mean platelet volume, NLR, QTcd, and Pd seems to have greater prognostic power than the sPESI scoring system.

The evolving role of cardiac troponin in the evaluation of cardiac disorders

Due to their tissue specificity and ease of detection, the cardiac troponins (cTn) have emerged as the most important and most utilized biomarkers for the diagnosis of acute myocardial infarction (AMI). The recent achievement of greater sensitivity by cTn assay systems, however, has resulted in the detection of cTn in a wide array of medical conditions, highlighting myocardial cellular necrosis as a feature in several, seemingly unrelated medical conditions, yet complicating the interpretation of a positive test. Since elevated cTn levels are associated with worse clinical outcomes and, thereby, influence medical decisions, careful consideration should be given to the method by which these biomarkers are measured, the patient population on which the test is being applied, and applicable thresholds based on particular clinical conditions. The objective of this review is to trace the clinical evolution of the cTn biomarker from a test for AMI to a general marker of myocardial cellular necrosis with clinically important prognostic information.

Fluorescence immunoassay of human D-dimer in whole blood

BACKGROUND

D-dimer is a widely used biomarker for the initial clinical assessment of suspected deep vein thrombosis and pulmonary embolism. Here, we presented a new fluorescence (FL) D-dimer assay system, which was developed with a platform of point-of-care test (POCT) for clinical applications.

METHODS

Whole blood was mixed with FL-labeled anti-D-dimer detector antibody, and then loaded onto a disposable cartridge. After 12 min of incubation, the FL intensity was acquired by scanning of test cartridge and converted as level of D-dimer in a laser FL scanner. The analytical performance of FL immunoassay was evaluated by linearity, recovery, and precision tests. The comparability of the developed assay was examined with automated reference methods.

RESULTS

The FL assay system showed a good linearity, and the analytical mean recovery of control was 103% in a dynamic working range. The imprecision of intra- and inter-as-say of coefficient of variations from assay system was less than 8%. The developed FL assay system showed strong correlation with two automated reference assays, Vidas D-dimer (r = 0.973) and Stalia D-dimer (r = 0.971).

CONCLUSION

The new FL immunoassay for D-dimer is a user-friendly, precise, and reproducible platform of POCT in whole blood.

D-dimer levels and 90-day outcome in patients with acute pulmonary embolism with or without cancer

BACKGROUND

The prognostic value of D-dimer testing in patients with acute pulmonary embolism (PE) has not been thoroughly studied.

METHODS

We used the RIETE Registry data to assess the 90-day prognostic value of increased IL Test D-dimer levels at baseline in patients with PE, according to the presence or absence of cancer.

RESULTS

As of May 2013, 3,283 patients with acute PE underwent D-dimer testing using IL Test D-dimer. Among 2,588 patients without cancer, those with D-dimer levels in the highest quartile had a higher rate of fatal PE (2.6% vs. 0.9%; p=0.002), fatal bleeding (1.1% vs. 0.3%; p=0.017) and all-cause death (9.1% vs. 4.4%; p<0.001) at 90 days compared with those with levels in the lowest quartiles. Among 695 patients with cancer, those with levels in the highest quartile had a similar rate of fatal PE or fatal bleeding but higher mortality (35% vs. 24%; p<0.01). On multivariate analysis, non-cancer patients with D-dimer levels in the highest quartile had an increased risk for fatal PE (odds ratio [OR]: 3.3; 95% CI: 1.6-6.6), fatal bleeding (OR: 4.3; 95% CI: 1.4-13.7) and all-cause death (OR: 2.1; 95% CI: 1.4-3.1) compared with patients with levels in the lowest quartiles.

CONCLUSIONS

Non-cancer patients with acute PE and IL Test D-dimer levels in the highest quartile had an independently higher risk for fatal PE, fatal bleeding and all-cause death at 90 days than those with levels in the lowest quartiles. In patients with cancer, D-dimer levels failed to predict fatal PE or fatal bleeding.

The emperor's new clothes: hypersensitivity of the new cardiac isoenzymes

Right ventricular (RV) myocardial infarction (MI) and pulmonary embolism (PE) are commonly recognized as two of the most challenging and vexing entities in clinical practice. When either is considered in a differential diagnosis, they warrant close consideration because of the life-threatening nature of these conditions. Their signs and symptoms overlap and, on rare occasions, they both can be simultaneously present in a single patient. Cardiac troponins are considered reliable markers of myocardial injury and are critical to the diagnosis of acute coronary syndromes. However, they can also be elevated in cases of PE. We herewith present a case of a woman who initially presented with syncope and then subsequently dyspnea. She manifested elevated cardiac isoenzymes, right-sided electrocardiogram abnormalities, and RV hypokinesis on echocardiography. She was initially diagnosed with RV infarct and managed with an interventional cardiology approach. However, her symptom of dyspnea persisted and the patient was eventually diagnosed with PE. Clinicians should entertain the diagnosis of PE in patients with elevated troponin I and evidence of right-sided cardiac compromise.