Hemodialysis and biomarkers of myocardial infarction - a cohort study

OBJECTIVES

End-stage renal disease is associated with a high risk of cardiovascular disease. We compared the concentration and prognostic ability of high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) and cardiac myosin-binding protein C (cMyC) among stable hemodialysis patients.

METHODS

Patients were sampled before and after hemodialysis. We measured hs-cTnI, hs-cTnT and cMyC and used Cox regressions to assess the association between quartiles of concentrations and all-cause mortality and a combination of cardiovascular events and all-cause mortality during follow-up.

RESULTS

A total of 307 patients were included, 204 males, mean age 66 years (SD 14). Before dialysis, 299 (99 %) had a hs-cTnT concentration above the 99th percentile, compared to 188 (66 %) for cMyC and 35 (11 %) for hs-cTnI. Hs-cTnT (23 %, p<0.001) and hs-cTnI (15 %, p=0.049) but not cMyC (4 %, p=0.256) decreased during dialysis. Follow-up was a median of 924 days (492-957 days); patients in the 3rd and 4th quartiles of hs-cTnT (3rd:HR 3.0, 95 % CI 1.5-5.8, 4th:5.2, 2.7-9.8) and the 4th quartile of hs-cTnI (HR 3.8, 2.2-6.8) had an increased risk of mortality. Both were associated with an increased risk of the combined endpoint for patients in the 3rd and 4th quartiles. cMyC concentrations were not associated with risk of mortality or cardiovascular event.

CONCLUSIONS

Hs-cTnT was above the 99th percentile in almost all patients. This was less frequent for hs-cTnI and cMyC. High cTn levels were associated with a 3-5-fold higher mortality. This association was not present for cMyC. These findings are important for management of hemodialysis patients.

Commercially Available Chest Radiograph AI Tools for Detecting Airspace Disease, Pneumothorax, and Pleural Effusion

Background Commercially available artificial intelligence (AI) tools can assist radiologists in interpreting chest radiographs, but their real-life diagnostic accuracy remains unclear. Purpose To evaluate the diagnostic accuracy of four commercially available AI tools for detection of airspace disease, pneumothorax, and pleural effusion on chest radiographs. Materials and Methods This retrospective study included consecutive adult patients who underwent chest radiography at one of four Danish hospitals in January 2020. Two thoracic radiologists (or three, in cases of disagreement) who had access to all previous and future imaging labeled chest radiographs independently for the reference standard. Area under the receiver operating characteristic curve, sensitivity, and specificity were calculated. Sensitivity and specificity were additionally stratified according to the severity of findings, number of findings on chest radiographs, and radiographic projection. The χ2 and McNemar tests were used for comparisons. Results The data set comprised 2040 patients (median age, 72 years [IQR, 58-81 years]; 1033 female), of whom 669 (32.8%) had target findings. The AI tools demonstrated areas under the receiver operating characteristic curve ranging 0.83-0.88 for airspace disease, 0.89-0.97 for pneumothorax, and 0.94-0.97 for pleural effusion. Sensitivities ranged 72%-91% for airspace disease, 63%-90% for pneumothorax, and 62%-95% for pleural effusion. Negative predictive values ranged 92%-100% for all target findings. In airspace disease, pneumothorax, and pleural effusion, specificity was high for chest radiographs with normal or single findings (range, 85%-96%, 99%-100%, and 95%-100%, respectively) and markedly lower for chest radiographs with four or more findings (range, 27%-69%, 96%-99%, 65%-92%, respectively) (P < .001). AI sensitivity was lower for vague airspace disease (range, 33%-61%) and small pneumothorax or pleural effusion (range, 9%-94%) compared with larger findings (range, 81%-100%; P value range, > .99 to < .001). Conclusion Current-generation AI tools showed moderate to high sensitivity for detecting airspace disease, pneumothorax, and pleural effusion on chest radiographs. However, they produced more false-positive findings than radiology reports, and their performance decreased for smaller-sized target findings and when multiple findings were present. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Yanagawa and Tomiyama in this issue.

Hemodialysis leads to plasma depletion of lectin complement pathway initiator molecule ficolin-2

INTRODUCTION

This study aimed to investigate changes in complement system-related molecules in patients undergoing hemodialysis.

METHODS

Patients >18 years of age on maintenance hemodialysis were included. Using enzyme-linked immunosorbent assays (ELISA) methods complement related molecules ficolin-1, ficolin-2, ficolin-3 mannose-binding lectin, long pentraxin 3, complement activation products C3c, and complement activation potentials were measured before and after a single hemodialysis treatment. All patients were dialyzed with synthetic high flux filters >1.6 m2 , respectively, Polyamix and Polysulfone, and the Kt/V was maintained >1.3.

FINDINGS

Three hundred and four patients were included. There was a modest decrease in plasma level of ficolin-1 (p < 0.001). Ficolin-2 was virtually depleted with median 3.9 (interquartile range [IQR]: 2.6-6.1, range 0.3-13.5) μg/ml before dialysis to median 0.0 (IQR: 0.0-0.5, range 0.0-5.5) μg/ml after dialysis (p < 0.001). No significant difference before and after hemodialysis was seen for mannose-binding lectin and long pentraxin 3 (p > 0.05). In a random subgroup of 160 patients ficolin-2-binding, ficolin-3-mediated lectin pathway capacity and classical pathway capacity were significantly decreased due to hemodialysis. The complement capacity of the alternative pathway was increased after hemodialysis (p = 0.0101), while mannose-binding lectin-mediated lectin pathway capacity was unaltered (p = 0.79). There was an increase in the complement activation product C3c (p < 0.0001), while the concentration of total C4 and C3 did not change (p > 0.158). Multivariate Cox proportional hazard analyses showed an increased risk for all-cause mortality with increasing ficolin-2 (p = 0.002) after hemodialysis.

DISCUSSION

Plasma ficolin-2 was virtually depleted from the circulation after hemodialysis. However, elevated plasma ficolin-2 levels after hemodialysis was independently associated with increased mortality.

Mid-regional pro-atrial natriuretic peptide levels before and after hemodialysis predict long-term prognosis

BACKGROUND

Mid-regional pro-atrial natriuretic peptide (MR-proANP) is a strong prognostic biomarker in cardiovascular disease but there is limited data for its use among patients undergoing dialysis.

METHODS

This was a cohort study of patients receiving maintenance hemodialysis from two Danish centers. Blood sampling and echocardiography were performed before and after a dialysis session. We calculated the area under the curve (AUC) for the receiver operating characteristics for diagnosing heart failure and Cox regressions for cardiovascular events and all-cause mortality.

RESULTS

Of the 306 patients, 284 (93%) had MR-proANP measurements both before and after dialysis. Median concentration was 642 pmol/L (IQR 419-858) before and 351 pmol/L (IQR 197-537) after dialysis, a mean decrease of 330 pmol/L (43%, CI 296-364, P < 0.001). MR-proANP concentration both before and after dialysis was negatively correlated to left ventricular ejection fraction with no difference in predictive ability for heart failure, AUC before and after dialysis were 0.60 (CI 0.50-0.70) and 0.61 (CI 0.51-0.71) (P = 0.40). Median follow-up was 32 months (IQR 31-33), during which 99 patients (32%) had a cardiovascular event and 110 (36%) died. A doubling of MR-proANP concentration was associated with a hazard ratio (HR) of 1.6 (CI 1.3-1.9) before and 1.7 (CI 1.4-2.0) after dialysis for mortality and a HR of 1.5 (CI 1.2-1.9) before and 1.4 (CI 1.2-1.7) after dialysis for cardiovascular events (all P < 0.001).

CONCLUSION

The MR-proANP concentration is elevated among patients undergoing hemodialysis and decreases during dialysis. MR-proANP concentration both before, after and intra-dialysis change strongly predicted cardiovascular events and all-cause mortality.

[Diagnostic imaging findings in COVID-19]

This is a review of diagnostic imaging findings in coronavirus disease-2019 (COVID-19). CT findings are frequently bilateral, multilobar and peripheral ground-glass opacities with vascular enlargements. Consolidations often appear during progression as well as crazy paving and reticulation. Lymphadenopathy, pleural effusions and pneumothorax are rare and should raise concern for other disease. Initially the CT can be normal, and the diagnostic performance for COVID-19 is not optimal. However, findings of characteristic ground-glass opacities during the ongoing epidemic should lead to considerations, that the patient may have COVID-19.

4309Structural or functional left sided heart disease found on echocardiographic screening is associated with a higher risk of death in patients with end stage renal disease receiving haemodialysis

Introduction

Cardiovascular disease is the leading cause of death in patients with end-stage renal disease on haemodialysis. Guidelines recommend echocardiography in all incident patients on dialysis and every three years, or when considered for kidney transplantation. The prognostic value of significant valve disease or reduced systolic function detected by echocardiographic screening is however not clear.

Purpose

We aimed to test the hypothesis that structural heart disease in an unselected, contemporary population of patients on maintenance dialysis is associated to a higher risk of death.

Methods

Adult chronic haemodialysis patients in two large dialysis centers had transthoracic echocardiography performed immediately prior to dialysis and were followed prospectively. Significant structural or functional left sided heart disease was defined as moderate or severe left-sided valve disease or left ventricular ejection fraction (LVEF) ≤40%.

Results

Among the 247 included patients (66 [IQR 64–67] years of age, 68% male), 54 (22%) had significant structural or functional left sided heart disease. An LVEF ≤40% was observed in 31 patients (13%). Severe or moderate aortic stenosis was present in 4 (2%) and 16 (7%) patients respectively, moderate mitral regurgitation in 4 (2%) patients and mitral stenosis in one (0.4%) patient. In more than half of the patients (56%), significant structural or functional left sided heart disease was not recognized prior to the study. After 2.8 years of follow-up, all-cause mortality was 52% for patients with significant heart disease and 32% for patients without significant structural heart disease (hazard ratio [HR] 1.95 (95% CI 1.25–3.06) (Figure). On multivariable adjusted Cox proportional hazard analysis, including age, sex, ischemic heart disease, diabetes, hypertension and time on dialysis, structural heart disease was an independent predictor of mortality with a HR of 1.60 (95% CI 1.01–2.55) along with age (HR per year 1.05 [95% CI 1.03–1.07]).

Kaplan-Meier estimate of survival

Conclusion

Left ventricular systolic dysfunction and moderate to severe valve disease are common and often unrecognized in patients with end-stage renal failure on haemodialysis and are associated with a higher risk of death.

The Copenhagen Triage Algorithm is non-inferior to a traditional triage algorithm: A cluster-randomized study

Introduction

Triage systems with limited room for clinical judgment are used by emergency departments (EDs) worldwide. The Copenhagen Triage Algorithm (CTA) is a simplified triage system with a clinical assessment.

Methods

The trial was a non-inferiority, two-center cluster-randomized crossover study where CTA was compared to a local adaptation of Adaptive Process Triage (ADAPT). CTA involves initial categorization based on vital signs with a final modification based on clinical assessment by an ED nurse. We used 30-day mortality with a non-inferiority margin at 0.5%. Predictive performance was compared using Receiver Operator Characteristics.

Results

We included 45,347 patient visits, 23,158 (51%) and 22,189 (49%) were triaged with CTA and ADAPT respectively with a 30-day mortality of 3.42% and 3.43% (P = 0.996) a difference of 0.01% (95% CI: -0.34 to 0.33), which met the non-inferiority criteria. Mortality at 48 hours was 0.62% vs. 0.71%, (P = 0.26) and 6.38% vs. 6.61%, (P = 0.32) at 90 days for CTA and ADAPT. CTA triaged at significantly lower urgency level (P<0.001) and was superior in predicting 30-day mortality, Area under the curve: 0.67 (95% CI 0.65–0.69) compared to 0.64 for ADAPT (95% CI 0.62–0.66) (P = 0.03). There were no significant differences in rate of admission to the intensive care unit, length of stay, waiting time nor rate of readmission within 30 or 90 days.

Conclusion

A novel triage system based on vital signs and a clinical assessment by an ED nurse was non-inferior to a traditional triage algorithm by short term mortality, and superior in predicting 30-day mortality.

Trial registration

Clinicaltrials.gov NCT02698319

The prognostic significance of lung function in stable heart failure outpatients

BACKGROUND

This study investigated the impact on all-cause mortality of airflow limitation indicative of chronic obstructive pulmonary disease or restrictive spirometry pattern (RSP) in a stable systolic heart failure population.

HYPOTHESIS

Decreased lung function indicates poor survival in heart failure.

METHODS

Inclusion criteria: NYHA class II-IV and left ventricular ejection fraction (LVEF) < 45%. Prognosis was assessed with multivariate Cox proportional hazards models. Two criteria of obstructive airflow limitation were applied: FEV₁ /FVC < 0.7 (GOLD), and FEV₁ /FVC < lower limit of normality (LLN). RSP was defined as FEV₁ /FVC > 0.7 and FVC<80% or FEV₁ /FVC > LLN and FVC <LLN.

RESULTS

There where 573 patients in the cohort (85% of eligible patients in study period). Median follow-up was 4.7 years and 176 patients died (31%). Age, NYHA class, smoking, body mass index and LVEF were independent prognostic factors (p<0.01). Obstructive airflow limitation increased mortality using both criteria (HR_GOLD 2.07 [95% CI 1.45-2.95] p<0.01 and HR_LLN 2.00 [1.40-2.84] p<0.01) and was an independent marker when using LLN criteria (HR 1.74 [1.17-2.59] p=0.006). RSP was independently associated with mortality when defined as FVC < LLN (HR 1.54 [1.01-2.35] p=0.04) but not as FVC < 80%. Multivariate hazard ratios for a 10% decrease in predicted value of FEV1 or FVC were 1.42 (p<0.001) and 1.33 (p<0.001) in patients exhibiting airflow obstruction, and 1.36 (p=0.031) and 1.38 (p=0.041) in RSP.

CONCLUSIONS

Presence of obstructive airflow limitation indicative of COPD or RSP were associated with increased all-cause mortality, however only independently when using the LLN definition.

The Copenhagen Triage Algorithm: a randomized controlled trial

Background

Crowding in the emergency department (ED) is a well-known problem resulting in an increased risk of adverse outcomes. Effective triage might counteract this problem by identifying the sickest patients and ensuring early treatment. In the last two decades, systematic triage has become the standard in ED’s worldwide. However, triage models are also time consuming, supported by limited evidence and could potentially be of more harm than benefit. The aim of this study is to develop a quicker triage model using data from a large cohort of unselected ED patients and evaluate if this new model is non-inferior to an existing triage model in a prospective randomized trial.

Methods

The Copenhagen Triage Algorithm (CTA) study is a prospective two-center, cluster-randomized, cross-over, non-inferiority trial comparing CTA to the Danish Emergency Process Triage (DEPT). We include patients ≥16 years (n = 50.000) admitted to the ED in two large acute hospitals. Centers are randomly assigned to perform either CTA or DEPT triage first and then use the other triage model in the last time period. The CTA stratifies patients into 5 acuity levels in two steps. First, a scoring chart based on vital values is used to classify patients in an immediate category. Second, a clinical assessment by the ED nurse can alter the result suggested by the score up to two categories up or one down. The primary end-point is 30-day mortality and secondary end-points are length of stay, time to treatment, admission to intensive care unit, and readmission within 30 days.

Discussion

If proven non-inferior to standard DEPT triage, CTA will be a faster and simpler triage model that is still able to detect the critically ill. Simplifying triage will lessen the burden for the ED staff and possibly allow faster treatment.

Trial registration

Clinicaltrials.gov: NCT02698319, registered 24. of February 2016, retrospectively registered

The formation and design of the TRIAGE study--baseline data on 6005 consecutive patients admitted to hospital from the emergency department

BACKGROUND

Patient crowding in emergency departments (ED) is a common challenge and associated with worsened outcome for the patients. Previous studies on biomarkers in the ED setting has focused on identification of high risk patients, and and the ability to use biomarkers to identify low-risk patients has only been sparsely examined. The broader aims of the TRIAGE study are to develop methods to identify low-risk patients appropriate for early ED discharge by combining information from a wide range of new inflammatory biomarkers and vital signs, the present baseline article aims to describe the formation of the TRIAGE database and characteristize the included patients.

METHODS

We included consecutive patients ≥ 17 years admitted to hospital after triage staging in the ED. Blood samples for a biobank were collected and plasma stored in a freezer (-80 °C). Triage was done by a trained nurse using the Danish Emergency Proces Triage (DEPT) which categorizes patients as green (not urgent), yellow (urgent), orange (emergent) or red (rescusitation). Presenting complaints, admission diagnoses, comorbidities, length of stay, and 'events' during admission (any of 20 predefined definitive treatments that necessitates in-hospital care), vital signs and routine laboratory tests taken in the ED were aslo included in the database.

RESULTS

Between September 5(th) 2013 and December 6(th) 2013, 6005 patients were included in the database and the biobank (94.1 % of all admissions). Of these, 1978 (32.9 %) were categorized as green, 2386 (39.7 %) yellow, 1616 (26.9 %) orange and 25 (0.4 %) red. Median age was 62 years (IQR 46-76), 49.8 % were male and median length of stay was 1 day (IQR 0-4). No events were found in 2658 (44.2 %) and 158 (2.6 %) were admitted to intensive or intermediate-intensive care unit and 219 (3.6 %) died within 30 days. A higher triage acuity level was associated with numerous events, including acute surgery, endovascular intervention, i.v. treatment, cardiac arrest, stroke, admission to intensive care, hospital transfer, and mortality within 30 days (p < 0.001).

CONCLUSION

The TRIAGE database has been completed and includes data and blood samples from 6005 unselected consecutive hospitalized patients. More than 40 % experienced no events and were therefore potentially unnecessary hospital admissions.