Differences in circulating cardiac troponin I and T in acute and chronic cardiac disease

Background

Clinical practice and guidelines assume that cardiac troponin I (cTnI) and cTnT are interchangeable, reflecting identical pathophysiological processes. However, it is unknown if cTnI and cTnT really are equivalent measures in different pathophysiological settings.

Purpose

To highlight potential differences in the release of cTnI and cTnT.

Methods

Large pooled cohort analysis including extensively characterized individuals, stratified into three groups: no cardiac disease (normal aging), chronic cardiac disease, and acute cardiac disease. Circulating cTnI and cTnT concentrations were measured blinded to clinical data using high-sensitivity assays (hs-cTnI-Architect, hs-cTnT-Elecsys) and their ratio calculated. Findings were validated using a second hs-cTnI assay (hs-cTnI-Clarity).

Results

Among 8719 individuals, 29% female, 10% had no known cardiac disease, 71% chronic cardiac disease, and 20% acute cardiac disease. Baseline characteristics including renal function were comparable between individuals with chronic and acute cardiac disease. Normal aging (without cardiac disease) was associated with a disproportional increase in cTnT versus cTnI (low cTnI/cTnT ratio, median 0.50, IQR 0.38–0.68). Although older, patients with chronic cardiac disease had a slightly higher cTnI/cTnT ratio (median 0.53, IQR 0.37–0.79, p<0.05). In contrast, in patients with acute cardiac disease, cTnI concentrations were disproportionally elevated compared to cTnT concentrations, resulting in a cTnI/cTnT ratio of 1.96 (IQR 0.93–4.73, p<0.001). Internal validation using a second hs-cTnI assay confirmed these findings.

Conclusion

These findings suggest relevant differences in the release of cTnI and cTnT with a greater release of cTnT versus cTnI in normal aging and a disproportional increase in cTnI versus cTnT in acute cardiac disease.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Swiss National Science Foundation

Performance of high-sensitivity cardiac troponin T versus I for the early diagnosis of myocardial infarction

Background

Clinical practice guidelines assume that both cardiac troponin (cTn) T and cTnI concentrations reflect identical pathophysiological processes and are equally effective in the detection of myocardial injury. However, there are differences between cTnT and cTnI that have been reported.

Purpose

The aim of this study was to directly compare the diagnostic performance of high-sensitivity cardiac troponin (hs-cTn) T versus hs-cTnI for the early diagnosis of acute myocardial infarction (MI).

Methods

In a prospective multicentre study, diagnostic and prognostic accuracies of hs-cTnT and I were analyzed in consecutive patients presenting to the emergency department with acute chest pain. The final diagnosis was adjudicated by two independent cardiologists using all information pertaining to the individual patient according to the fourth universal definition of MI. Adjudication of the final diagnoses was performed twice: once using serial measurements of hs-cTnT and once using hs-cTnI. Furthermore, the clinical performance of hs-cTnT/I when embedded in the European Society of Cardiology (ESC) 0/1h-algorithm was assessed.

Results

Among 5087 consecutive patients (median [Interquartile range, IQR] age 61 [49.0, 74.0] years, 33.2% female), 951 (18.7%) and 901 patients (17.7%) had an adjudicated final diagnosis of non-ST-segment elevation myocardial infarction (NSTEMI) when using serial measurements of hs-cTnT and hs-cTnI for adjudication, respectively. Diagnostic accuracy was very high for both hs-cTnT and hs-cTnI and comparable when using hs-cTnT for adjudication (hs-cTnT: area under the curve [AUC] 0.93 [95% CI 0.92–0.94] versus hs-cTnI AUC 0.93 [95% CI 0.92–0.94]; p=0.891). However, when using serial measurements of hs-cTnI for adjudication, diagnostic accuracy was significantly higher for hs-cTnI (AUC 0.93 [95% CI 0.92–0.94] versus AUC 0.94 [95% CI 0.94–0.95], p<0.001; Figure 1). This was confirmed in subgroup analyses including early presenter (≤3h), patients with renal failure, known coronary artery disease and elderly (≥70 years). However, both assays performed excellent with very high safety for rule-out and high accuracy for rule-in MI when embedded in the ESC 0/1h-algorithm. Prognostic accuracies for 730-day all-cause mortality and cardiovascular death were significantly higher for hs-cTnT compared to hs-cTnI (Figure 2).

Conclusions

While there seem to be differences between hs-cTnT and hs-cTnI in their diagnostic and prognostic performance, clinical relevance needs to be further evaluated since both assays performed excellent when embedded in their respective early triage algorithms.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Swiss National Foundation, Swiss Heart Foundation

Combining qualitative and quantitative ECG criteria with the ESC 0/1h-hs-cTn-algorithm in the early diagnosis of non-ST-elevation myocardial infarction

Background

The electrocardiogram (ECG) is one of the three main diagnostic tools for the assessment of patients with suspected non-ST-elevation myocardial infarction (NSTEMI). However, it is unknown how established qualitative or novel quantitative ECG criteria can best be combined with high-sensitivity cardiac troponin (hs-cTn)-based diagnostic algorithms, such as the ESC 0/1h-algorithm, for the early diagnosis of NSTEMI.

Methods

ST-segment depression, T-wave inversion, and a novel modified ST-segment deviation score (1), defined as the sum of ST-segment elevation in aVR plus absolute, unsigned ST-segment depressions in the remaining leads, were assessed blinded to all clinical data among unselected patients presenting with acute chest discomfort to the emergency department in an international multicentre prospective diagnostic study. Final diagnoses were centrally adjudicated by two independent cardiologists based on complete cardiac work-up, cardiac imaging and serial hs-cTn. Direct rule-in thresholds for the modified ST-segment deviation score, achieving a positive predictive value (PPV) of >70% justifying early monitorization and management, were derived, validated and compared to ST-segment depression and T-wave inversion and applied 1) alone and 2) in combination with the ESC 0/1h-hs-cTnT/I-algorithms.

Results

Among 3299 eligible patients, NSTEMI was present in 581 (17.6%) patients. ST-segment depression identified 243/3299 patients (7.4%) with a specificity of 96.5% (95% CI 95.7–97.1) and a PPV of 60.5% (95% CI 54.2–66.4) for the rule-in of NSTEMI, while T-wave inversion had a low PPV (38.0%; 95% CI 33.1–43.1). A modified ST-segment deviation score ≥6mm triaged 108/3299 patients (3.3%) towards direct rule-in upon ED arrival, resulting in a PPV of 71.3% (95% CI 62.1–79.0) and a specificity of 98.9% (95% CI 98.4–99.2), Figure 1. Bootstrap internal validation confirmed the robustness of these findings. Most patients ruled-in by ST-segment depression or a modified ST-segment deviation score ≥6mm would have been also ruled-in by the ESC 0/1h-hs-cTnT/I-algorithm, albeit 1–2h later. Combining ST-segment depression or a modified ST-segment deviation score ≥6mm with the ESC 0/1h-hs-cTnT-algorithm (Figure 2) accelerated the rule-in in those identified already by the ECG-criteria, and resulted in a modest number of reclassifications from rule-out or observe to rule-in. These results were confirmed in a secondary analysis assessing the combination of these ECG signatures with two ESC 0/1h-hs-cTnI-algorithms (Architect and Centaur).

Conclusion

Combining either ST-segment depression or a modified ST-segment deviation Score ≥6mm with the ESC 0/1h-hs-cTnT/I-algorithms accelerated and improved the early diagnosis of NSTEMI.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss Heart Foundation (SHF) and Swiss National Science Foundation (SNSF)

Renal failure: a non-cardiac source of high sensitivity cardiac troponin T

Background

Circulating high sensitivity cardiac troponin T (hs-cTnT) levels are frequently elevated in patients with end-stage renal disease (ESRD). The underlying pathophysiology is largely unknown. Currently, accumulation of hs-cTnT due to impaired renal clearance, as well as increased production caused by chronic cardiomyocyte injury is being discussed.

Purpose

The aim of this study was to assess the relative contribution of impaired renal clearance as a non-cardiac source of elevated hs-cTnT concentrations, using renal transplantation as an in vivo model of rapidly improved renal function and on a short-term basis rather unchanged cardiac pathology.

Methods

This single-centre study was a secondary analysis within a prospective active surveillance study program for perioperative myocardial infarction/injury (PMI). 42 consecutive high-risk patients undergoing renal transplantation without evidence of PMI were included. Serial creatinine and hs-cTnT (Elecsys, Roche) measurements were performed pre-transplant (baseline) and post-transplant on day (d) 1, between d2 and d5, and between d14 and d180. The effect of time and creatinine on hs-cTnT was estimated with a log-level non-linear mixed-effects model, where time and creatinine were treated as the fixed effects and subject as the random effect. Natural cubic splines were used to account for nonlinearity in the fixed effects.

Results

Baseline median serum creatinine concentration was 616 umol/L [interquartile range (IQR) 477–825], and significantly fell to 425 umol/L (IQR 313–619) on d1, 285 umol/L (IQR 194–509) on day2–5, and 116 umol/L (IQR 100–166) on d14–180 (p<0.001, p<0.001, and p=0.043, respectively; Figure 1A).

Pre-transplant hs-cTnT concentrations were above the 99th percentile (14ng/L) in all patients, median hs-cTnT concentration was 50 ng/L (IQR 35–70). In parallel to the fall in serum creatinine from baseline to d1, hs-cTnT concentrations significantly fell to 28 ng/L (IQR 15–40) on d1 (p<0.001), and then remained constant on d2–5 (27 ng/L (IQR 18–35)), and on d14–180 (24 ng/L (IQR 19–28); Figure 1B).

The mixed-effect model showed a significant decrease of hs-cTnT between baseline and d1 (p<0.001), whereas no significant change between d1 and d2 (p=0.82) occurred (Figure 2).

Conclusion

In contrast to the continuously falling serum creatinine levels, hs-cTnT concentrations reduced by about 50% only within the first 24 hours with a functional graft and then remained elevated above the 99th percentile. This suggests, that ESRD is a non-cardiac source of elevated circulating hs-cTnT concentrations, which contributes about 50%, while the other 50% seem related to chronic cardiomyocyte injury. Further studies assessing the long-term effect of renal transplantation on hs-cTnT levels and cardiac function are needed.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Swiss National Science FoundationSwiss Heart Foundation

Prevalence, patient characteristics and outcome of hyponatremia in acute heart failure

Background

Hyponatremia is the most common electrolyte disturbance found in hospitalized patients. Previous studies have shown that low serum sodium levels at presentation are associated with increased mortality and morbidity in patients hospitalized with acute heart failure (AHF). However, given the complicated multifactorial origin of hyponatremia, the role of serum sodium level in risk stratification in patients with AHF is still largely unknown.

Purpose

To evaluate the prevalence and prognostic value of hyponatremia in patients presenting with AHF to the emergency department (ED).

Methods

Basics in Acute Shortness of Breath EvaLuation (BASEL V) was a prospective, multicenter, diagnostic study recruiting dyspneic patients at the ED. The final diagnosis of AHF was adjudicated by 2 independent physicians. Hyponatremia was defined as a serum sodium level of <135 mmol/l. The prognostic accuracy of hyponatremia in predicting all-cause mortality and a composite outcome of death and heart failure (HF) rehospitalization was quantified using multivariable adjusted Cox regression. Adjustments were made for the following variables: age, sex, history of ischemic heart disease, previous HF, infection as a trigger of AHF, systolic blood pressure, glomerular filtration rate and log-transformed N-terminal pro-B-type natriuretic peptide (NT-proBNP) at presentation. The incremental value of hyponatremia to the MEESSI-Score, a validated AHF risk score, was quantified using area under the curve (AUC) analyses.

Results

Among 1572 patients with AHF, 1499 patients were eligible for the main analysis, of whom 215 (14.3%) had hyponatremia, 1249 (83.3%) normonatremia and 35 (2.3%) hypernatremia at presentation. Of those with hyponatremia, 21 (9.8%) and 54 (25.1%) patients died, 27 (12.6%) and 79 (36.7%) patients experienced the composite outcome within 30 and 180 days, respectively. Multivariable adjusted hazard ratios (aHR) were 0.97 (95%-CI 0.94–1.01) and 0.97 (95%-CI 0.95–0.99) for mortality, 0.97 (95%-CI 0.94–1.00) and 0.98 (95%-CI 0.95–0.99) for the composite outcome within 30 and 180 days, respectively. The risk for mortality and a composite of all-cause mortality and HF rehospitalization within 180 days after presenting to the ED with AHF rose significantly with a lower sodium level at presentation. Each 1-unit decrease in sodium level [mmol/L] was associated with a 3% and 2.7% increase in the hazard rate of mortality (aHR 0.97, p=0.01) and the composite outcome (aHR 0.98, p=0.01), respectively. While in the 30-day analyses after multivariable adjustment sodium had no significant prognostic value. The already excellent predictive ability of the MEESSI-Score for 30-day mortality was not enhanced by sodium level (AUC 0.80 versus 0.80, p=0.834).

Conclusion

Hyponatremia at presentation is associated with a higher risk of 180-day mortality in patients with AHF. However, its role as an independent prognostic marker in risk stratification remains unclear.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss National Science FoundationSchweizerische Herzstiftung

Using high-sensitivity cardiac troponin for the exclusion of inducible myocardial ischemia in patients without previously known coronary artery disease

Background

The rapid and safe exclusion of functionally relevant coronary artery disease (CAD) is a crucial, yet unmet clinical need. High-sensitivity cardiac troponin (hs-cTn) may be an attractive strategy, particularly in patients without previously known CAD.

Purpose

To derive and internally validate optimal rule-out cutoffs for an early and safe exclusion of functionally relevant CAD in symptomatic patients without previously known CAD.

Methods

In an ongoing single-center, prospective, cohort study, we enrolled consecutive patients without previously known CAD that were referred with symptoms possibly related to functionally relevant CAD. Cardiac troponin concentrations were measured at presentation using two high-sensitivity assays (Elecsys hs-cTnT and Architect hs-cTnI). Presence of functionally relevant CAD was adjudicated by 2 independent cardiologists, blinded to hs-cTn measurements, using MPI-SPECT/CT in all patients, as well as coronary angiography and fractional flow reserve measurements, whenever available. The primary diagnostic outcome was safety for early rule-out of functionally relevant CAD, quantified by sensitivity and the negative predictive value (NPV). The co-primary prognostic outcomes were cumulative incidences of cardiovascular death and all-cause death after 5 years. A NPV ≥90% and sensitivity ≥90% were predefined as acceptable performance criteria. The derived cutoffs were further evaluated in pre-specified subgroups. Internal validity was assessed with a bootstrapping procedure for a realistic estimate in similar future patients. Cumulative incidence curves stratified by the presence of functionally relevant CAD and hs-cTn concentrations below and above the derived cutoffs were constructed.

Results

Among 2111 eligible patients, 498 (23.6%) had a final diagnosis of functionally relevant CAD. Median age was 68 years and 938 (44.4%) were female. For ruling out functionally relevant CAD, a hs-cTnT concentration <5 ng/L resulted in a sensitivity of 90.8% (95% CI: 87.9–93.0%) and a NPV of 90.2% (95% CI: 87.1–92.5), triaging 468 (22.2%) patients towards rule-out. Similarly, a hs-cTnI concentration <2 ng/L resulted in a sensitivity of 91.6% (95% CI: 88.8–93.7%) and a NPV of 90.0% (95% CI: 86.8–92.6), triaging 422 (20.0%) patients. Internal validation showed robustness of these findings. The diagnostic performance of the derived cutoffs did not significantly vary across the subgroups. Hs-cTn concentrations above the derived cutoffs were associated with a substantially higher cumulative event rate of cardiovascular death (hs-cTnT: 7.0% vs. 0.8%; hs-cTnI: 6.6% vs. 1.2%) and all-cause death (hs-cTnT: 14.3% vs. 2.4%; hs-cTnI: 13.1% vs. 4.4%) during 5-years follow-up (log rank p<0.001 for all).

Conclusion

In symptomatic patients without previously known CAD, very low hs-cTn concentrations may generally allow to safely and effectively exclude functionally relevant CAD.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss National Science FoundationSwiss Heart Foundation

CA 125 in the diagnosis and risk stratification of acute heart failure

Background

Recent evidence confirms the elevation of CA 125 in non-tumor processes such as acute heart failure (AHF). However, the utility of this novel biomarker for diagnosis, prognosis, and therapy guidance in AHF remains unclear.

Purpose

To investigate the potential of CA 125 for diagnosis, prognosis and therapy guidance in unselected AHF patients presenting with acute dyspnea to the emergency department (ED).

Methods

We quantified CA 125 in a blinded fashion among patients presenting with acute dyspnea to the ED in a multicenter diagnostic study. Final diagnosis of AHF including AHF-phenotype was centrally adjudicated by two independent cardiologists. To further characterize CA 125's potential in AHF correlations with established biochemical and imaging markers were assessed. Diagnostic accuracy for AHF was quantified by the area under the receiver operating characteristic curve (AUC). All-cause mortality within 360 days was the prognostic endpoint.

Results

Among 470 patients eligible for this analysis, 268 (57.0%) had adjudicated AHF. CA 125 concentrations at presentation were significantly higher among AHF patients vs. patients with other final diagnoses (45.8 U/ml [interquartile range (IQR), 18.5–110.3] vs. 16.2 U/ml [IQR, 9.6–31.6], p<.001). Patients with worsening heart failure had significant higher CA 125 levels compared to other heart failure phenotypes (p=.018). There was a significant positive correlation of CA 125 and high-sensitivity cardiac troponin T and NTproBNP and a significant negative correlation of CA 125 and left ventricular ejection fraction (correlation coefficients 0.204, 0.220, −0.331, respectively; all ps<.001). CA 125's AUC for AHF was significantly lower compared to NTproBNP's in the overall population (0.72, 95% confidence interval (CI) 0.67–0.76 vs. 0.93, 95% CI 0.90–0.95, p<.001, Figure 1) and in predefined subgroups according to age, gender and renal function. Among 268 AHF patients, 84 (31.3%) died within 360 days of follow-up. CA 125 plasma concentrations above the median indicated increased risk of all-cause mortality (hazard ratio 2.06, 95% CI 1.31–3.24; p=.002, Figure 2). CA 125's prognostic accuracy for 360-days mortality was comparable with NT-proBNP's and high-sensitivity cardiac troponin T's. CA 125 did not independently predict all-cause mortality at 360 days when used in validated multivariable regression models and had no interactions with medical therapies at discharge.

Conclusion

CA 125 may aid physicians in the risk stratification and rapid triage of patients with suspected AHF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Swiss National Science FoundationSwiss Heart Foundation Figure 1. ROC curve comparisonFigure 2. Kaplan-Meier curve 360 days mortality

Derivation and validation of a novel 3-hour pathway for the observe-zone of the ESC 0/1h-algorithm

Background

The latest non-ST elevation myocardial infarction (NSTEMI) guidelines from the European Society of Cardiology (ESC) recommend a 3h cardiac troponin determination in patients triaged to the observe-zone of the ESC 0/1h-algorithm; however, no specific cut-off for further triage is endorsed.

Purpose

To derive and internally, as well as externally, validate a novel 3-hour pathway for the observe-zone of the ESC 0/1h-algorithm.

Methods

In an ongoing multicentre international diagnostic study, we prospectively enrolled unselected patients presenting to the emergency department with symptoms suggestive of myocardial infarction (MI). Final diagnoses were centrally adjudicated by two independent cardiologists applying the 4th universal definition of MI, based on complete cardiac work-up including cardiac imaging, serial high sensitivity cardiac troponin T (hs-cTnT) sampling and 90-day follow-up information. High sensitivity-cTnT concentrations were measured at presentation and after 1 and 3 hours. The primary outcome was safety, quantified by the sensitivity and NPV for early rule out of NSTEMI. External validation was performed in an independent multicentre international study.

Results

Among 2076 eligible patients, application of the ESC 0/1h-algorithm triaged 1512 patients (72.8%) to either rule-out or rule-in of NSTEMI, remaining 564 patients (27.2%) in the observe-zone (adjudicated NSTEMI prevalence 120/564 patients, 21.3%). The novel derived 3h-pathway for the observe-zone patients ruled-out NSTEMI with a 3h hs-cTnT concentration <15 ng/L and a 0/3h-hs-cTnT absolute change <4 ng/L, triaging 138 patients (25%) towards rule-out, resulting in a sensitivity of 99.2% (95% CI 96.0–99.9) and a NPV of 99.3% (95% CI 95.4–99.9). A 0/3h-hs-cTnT absolute change ≥6 ng/L ruled-in 63 patients (11.2%), resulting in a specificity of 98% (95% CI 96.2–98.9) and a PPV of 85.7% (95% CI75.0–92.3). The novel 3h-pathway reduced the number of patients in the observe zone by 36%, and the number of T1MI by 50% (Figure 1). Findings were confirmed in both internal and external validation.

Conclusions

A novel derived pathway combining a 3h hs-cTnT concentration <15 ng/L and a 0/3h absolute change <4 ng/L allowed to very safely rule-out NSTEMI in patients remaining in the observe-zone of the ESC 0/1h-algorithm.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Swiss Heart FoundationThe Swiss National Science Foundation Figure 1

Discordance in prognostic ability between physician assessed NYHA classification and self-reported health status in patients with acute heart failure

Background

Especially in patients with acute heart failure (AHF) the NYHA classification remains of uncertain representation of patients' actual health state. Alternatively, patient's subjective well-being, in terms of health-related quality of life (HRQL), showed to have an excellent prognostic ability in out clinic patients with chronic heart failure.

Objectives

It is unknown whether HRQL instruments can assess a more reliable prognostication in patients hospitalized due to AHF than the NYHA classification.

Methods

Goal Directed Afterload Reduction in Acute Congestive Cardiac Decompensation Study (GALACTIC) was a multicenter, randomized, open-label blinded-end-point trial that emphasized early intensive and sustained vasodilation in adult patients hospitalized due to AHF with NYHA functional class III/IV, however provided neutral findings. HRQL was assessed by the generic EQ-5D-3L which is a 3-leveled 5-item instrument and the disease-specific Kansas City Cardiomyopathy Questionnaire (KCCQ). Unadjusted and adjusted Cox regression models were performed after patients were grouped into low (EQ-5D −0.074<0.25; KCCQ 0<25), moderately low (0.25<0.5; 25<50), moderately high (0.5<0.75; 50<75) and high HRQL (0.75–1.0; 75–100).

Results

781 patients were enrolled in 10 centres in 5 countries over 2 continents among which 536 (69%) patientshad completed theEQ-5D and 419 (54%) the KCCQ shortly after admission. Within 180 days of follow-up69 (13%) and 54 (13%) patients died and 151 (28%) and 122 (29%) died or were rehospitalized due to AHF, respectively. Cumulative incidence as well as HRs in patients grouped according to NYHA (n=536) indicated a comparable or significantly lower risk in patients with NYHA IV: e.g. for the combined outcome HR 1.07 (95% CI 0.777–1.473) and aHR 0.463 (95% CI 0.245–0.875). Whereas HRs in patients grouped according to both, EQ-5D (n=536) and KCCQ (n=419), increased from the group with highest to the group with the lowest HRQL: e.g. aHR for moderately high 1.11 (95% CI 0.718–1.715), for moderately low 1.721 (95% CI 1.102–2.688) and for low EQ-5D index 1.891 (95% CI 1.136–3.149) referenced to high HRQL (EQ-5D index 0.75–1.0).

Conclusions

These findings corroborate and extend previous work suggesting that NYHA classification poorly discriminates AHF patients' prognosis and challenge its' extensive application. HRQL might be a possible alternative to easily assess these patients' heath state.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation A. 180-day mortality; B. composite outcome

Prognostic value of self-reported subjective exercise capacity in patients with acute dyspnea

Background

Quantitative assessment of self-reported exercise capacity as provided by the Duke Activity Status Index (DASI) is a validated measure of exercise capacity in stable ambulatory patients.

Objectives

This study aimedto test whether the quantification of self-reported exercise capacityusing the DASI may aid physicians in the risk stratification of patients presenting with acute dyspnea to the emergency department (ED).

Methods

Basics in Acute Shortness of Breath EvaLuation (BASEL V) was a prospective cohort study recruiting dyspneic patients at the ED. The prognostic value and accuracy of theDASI assessed shortly after presentation were quantified using Cox regression analyses and the Area under the curve (AUC).

Results

Among 1019 patients eligible for this analysis 529 (51.9%) had an adjudicated final diagnosis of acute heart failure, 75 (7.4%) and 297 (29.1%) patients died within 90 and 720 days after presentation. Unadjusted hazard ratios (HR) and multivariable adjusted hazard ratios (aHR) for 90-day and 720-day mortality increased continuously from the fourth (best self-reported exercise capacity) to the first DASI-quartile (worst self-reported exercise capacity). For 720-day mortality in the first quartile theHR was 9.1 (95%-CI 5.5–14.9) (aHR 6.1 [95%-CI 3.7–10.1]), in the second quartile 6.4 (95%-CI 3.9–10.6) (aHR 4.4 [95%-CI 2.6–7.3]), while in the third quartile the HR was 3.2 (95%-CI 1.9–5.5) (aHR 2.4 [95%-CI 1.4–4.0]). The prognostic accuracy of the DASI was moderate-to-high and higher than that of B-type natriuretic peptide (BNP) and NT-proBNP (N-terminal pro-BNP) concentrations, e.g. for 720-day mortality prediction AUC 0.70 versus 0.64, p=0.020; 0.72 versus 0.68, p=0.074.

Conclusions

Quantification of self-reported subjective exercise capacityusing the DASI provides moderate-to-high prognostic accuracy in patients presenting with acute dyspnea to the ED and may aid physicians in further risk stratification.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union, the Swiss National Science Foundation. Duke Activity Status Index

Early standardized clinical judgement for syncope diagnosis in the emergency department

BACKGROUND

The diagnosis of cardiac syncope remains a challenge in the emergency department (ED).

OBJECTIVE

Assessing the diagnostic accuracy of the early standardized clinical judgement (ESCJ) including a standardized syncope-specific case report form (CRF) in comparison with a recommended multivariable diagnostic score.

METHODS

In a prospective international observational multicentre study, diagnostic accuracy for cardiac syncope of ESCJ by the ED physician amongst patients ≥ 40 years presenting with syncope to the ED was directly compared with that of the Evaluation of Guidelines in Syncope Study (EGSYS) diagnostic score. Cardiac syncope was centrally adjudicated independently of the ESCJ or conducted workup by two ED specialists based on all information available up to 1-year follow-up. Secondary aims included direct comparison with high-sensitivity cardiac troponin I (hs-cTnI) and B-type natriuretic peptide (BNP) concentrations and a Lasso regression to identify variables contributing most to ESCJ.

RESULTS

Cardiac syncope was adjudicated in 252/1494 patients (15.2%). The diagnostic accuracy of ESCJ for cardiac syncope as quantified by the area under the curve (AUC) was 0.87 (95% CI: 0.84-0.89), and higher compared with the EGSYS diagnostic score (0.73 (95% CI: 0.70-0.76)), hs-cTnI (0.77 (95% CI: 0.73-0.80)) and BNP (0.77 (95% CI: 0.74-0.80)), all P < 0.001. Both biomarkers (alone or in combination) on top of the ESCJ significantly improved diagnostic accuracy.

CONCLUSION

ESCJ including a standardized syncope-specific CRF has very high diagnostic accuracy and outperforms the EGSYS score, hs-cTnI and BNP.

A comprehensive secondary prevention benchmark (2PBM) score identifying differences in secondary prevention care in patients after acute coronary syndrome

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Unrestricted grands from AstraZeneca, Boehringer Ingelheim and Sanofi

Background

Reaching secondary prevention targets improves long-term prognosis in patients after acute coronary syndrome (ACS). Although prevention targets are defined by guidelines, their achievement rates are insufficiently documented. Suitable benchmarking tools are lacking.

Purpose

 We aimed to determine the degree of secondary prevention care by creating a secondary prevention benchmark score (2PBM) and using it in patients undergoing ambulatory cardiac rehabilitation (CR) after an acute coronary syndrome. 

Methods

In this observational cohort study, 472 consecutive ACS patients who completed the local ambulatory CR programme between 2017-2019 were included. Benchmarks for secondary prevention medication, clinical and lifestyle targets were predefined and combined in the complete 2PBM with maximum 10 points. The association of patient characteristics and achievement rates of individual components and the complete 2PBM were assessed using multivariable logistic regression analysis. 

Results

Patients were on average 62 ± 11 years old and predominantly male (n = 406; 86%). Type of ACS was ST-elevation myocardial infarction (STEMI) in 241 patients (51%) and non-ST-elevation myocardial infarction in 216 patients (46%). Achievement rates for individual components of the 2PBM were 71% for medication, 35% for clinical and 61% for lifestyle benchmarks. Achievement of medication benchmark was associated with younger age [odds ratio (OR): 0.979, 95% confidence interval (CI) 0.959-0.996, p = 0.021] and history of STEMI [OR: 2.05, 95% CI 1.35-3.12, p = 0.001]. Achievement of clinical benchmark was associated with medication benchmark [OR: 1.66, 95% CI 1.03-2.71, p = 0.042]. The complete 2PBM was achieved by 74 patients (16%), while 362 patients (77%) reached ≥8 points. Achievement of complete 2PBM was independently associated with a history of STEMI [OR: 1.79, 95 CI 1.06-3.08 p = 0.032]. 

Conclusion

Benchmarking with 2PBM identifies gaps and achievements in secondary prevention care. A history of STEMI was associated with the highest 2PBM score, suggesting best secondary prevention care in patients after STEMI. 2PBM may be used for internal quality control, comparison of cohorts and future correlation studies between CR targets and outcomes.

Abstract Figure.

Development and validation of an ECG-based cardiac syncope risk calculator

Background

The early diagnosis of cardiac syncope is often challenging. We therefore developed an ECG-based risk calculator as an aid for rapid rule-out or rule-in of cardiac syncope and aimed to validate this decision tool.

Methods

In a prospective diagnostic international multicenter study (derivation cohort), 2007 patients, 40 years or older, presenting with syncope to the emergency department were recruited. The primary diagnostic outcome, cardiac syncope, was centrally adjudicated by two independent cardiologists using all clinical information obtained during syncope work-up including 12-month follow up. 12-lead ECG was recorded at presentation and read by residents blinded to clinical information. Significant ECG predictors of cardiac syncope were identified using penalized backward selection. Findings were validated in an independent US multicenter cohort with 2'269 syncope patients.

Results

In the derivation cohort (median age 71 years, 40% women), centrally adjudicated cardiac syncope was present in 267 patients (16%). Seven ECG criteria (rhythm, heart rate, corrected QT-interval, ST-segment depression, atrioventricular-block, bundle-branch-block and ventricular extrasystole/non-sustained ventricular tachycardia) were identified as significant predictors for cardiac syncope and combined into the bAseL Ecg Risk calculaTor for Cardiac Syncope (ALERT-CS). Diagnostic accuracy of ALERT-CS for cardiac syncope, as quantified by the area under the receiver-operating characteristics curve (AUC), was high (0.80, 95%-confidence interval (CI) 0.77–0.83) and significantly higher compared to the EGSYS score (0.73, 95% CI 0.70–0.76, p&lt;0.001). In combination, ALERT-CS significantly increased the AUC of BNP (0.82, 95% CI 0.79–0.85 vs 0.77, 95% CI 0.74–0.81, p=0.003), hs-cTnT (0.84, 95% CI 0.0.81–0.87 vs 0.77, 95% CI 0.74–0.80, p&lt;0.001) and integrated clinical judgment in the ED (0.90, 95% CI 0.89–0.92 vs 0.87, 95% CI 0.84–0.90, p&lt;0.001).

A predicted probability for cardiac syncope below 5.5% by ALERT-CS identified 138 patients (8%) eligible for triage towards rapid rule-out of cardiac syncope with a sensitivity of 99%. A predicted probability above 37.5% identified 181 patients (11%) eligible for triage towards rapid rule-in of cardiac syncope with a specificity of 95%. Prognostic verification for 30-day major adverse cardiac events (MACE) showed a high rate of MACE in the rule-in group and a very low rate of MACE in the rule-out group (Figure).

External validation (median age 72 years, 48% women) showed similar diagnostic accuracy (AUC 0.76, 95% CI 0.73–0.79) and prognostic results.

Conclusion

Combining seven ECG criteria within the simple ALERT-CS may aid ED physicians in the early rule-out or rule-in of cardiac syncope.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, Swiss Heart Foundation

Early diagnosis of acute myocardial infarction in patients with a history of percutaneous coronary intervention

Background

Recurrence of acute chest pain after percutaneous coronary intervention (PCI) is common. The early detection of acute myocardial infarction (AMI) as a possible cause of acute chest pain can be challenging in patients with a history of PCI due to e.g. pre-existing electrocardiographic abnormalities. It is unknown, whether high-sensitivity cardiac troponin T (hs-cTnT) concentrations and hs-cTnT-based rapid algorithms perform equally well in patients with a history of PCI.

Purpose

To investigate the impact of prior PCI on the diagnostic performance of hs-cTnT concentrations for early rule-out and rule-in of AMI.

Methods

In an ongoing multicentre international study, we prospectively enrolled unselected patients presenting to the emergency department (ED) with symptoms suggestive of AMI. Final diagnoses were centrally adjudicated by two independent cardiologists using all available medical records obtained during clinical care including 90 day follow-up information and cardiac imaging. High-sensitivity cTnT concentrations at presentation and after 1h were compared against the adjudicated final diagnosis. Patients were stratified according to the presence or absence of previous PCI.

Results

Among 5536 patients (1313 with and 4223 without previous PCI), incidence of AMI was significantly higher in patients with previous PCI (26.3% versus 21.4%; p&lt;0.001). Patients with prior PCI and a final diagnoses other than AMI had significantly higher concentrations of hs-cTnT at presentation to the ED (median 9ng/l [IQR 6 to 15.8] vs 5.5ng/l [IQR 3 to 10]; p&lt;0.001). However, in patients with final adjudicated diagnosis of AMI, hs-TnT concentrations at presentation were lower in patients with previous PCI (median 46ng/l [IQR 23 to 94] vs 55ng/l [IQR 25 to 175]; p=0.003). The diagnostic accuracy of hs-cTnT was high in patients with history of PCI, but significantly lower compared to patients without PCI (AUC 0.91 [95% CI 0.89–0.92] versus AUC 0.94 [95% CI 0.94–0.95]; p&lt;0.001, respectively). When applying the ESC 0/1-algorithm among patients with previous history of PCI, the rule out pathway showed also very high safety in patients with a history of PCI (sensitivity 99.2 [95% CI 97.2–99.8] and negative predictive value 99.6 [95% CI 98.5–99.9]). However, the efficacy of the ESC 0/1h-algorithm for early rule out of NSTEMI was lower in the PCI group compared to no PCI (45.2% vs 65.1%; P&lt;0.001, respectively), triaging more patients to the observe zone (36.8% versus 18.8%; p&lt;0.001). Time to discharge from the ED was significantly longer in patients with prior PCI (334 min vs 290 min; p&lt;0.001). When stratified for index AMI, patients with history of PCI waited longer for a final diagnoses of AMI (285 vs 217 min; p&lt;0.001).

Conclusions

History of PCI impacts on the diagnostic performance of hs-cTnT. Although the ESC 0/1h-algorithm still performs very safe when applied to patients with a history of PCI, its efficacy is significantly reduced.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the KTI, the Stiftung für kardiovaskuläre Forschung Basel the University of Basel and the University Hospital Basel

Incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope

Background

Cardiac syncope has been shown to carry the highest hazard for all-cause death compared to other causes of syncope including vasovagal and orthostatic syncope. However, little is known about the incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope.

Purpose

To evaluate the incidence, characteristics and prognosis of different cardiac etiologies underlying cardiac syncope.

Methods

We enrolled patients presenting to the emergency department (ED) with syncope in a large prospective international multicentre study. The cause of syncope (cardiac vs non-cardiac) including the detailed cardiac aetiology (if cardiac) was centrally adjudicated by two independent cardiologists based on detailed in-hospital as well as outpatient cardiac work-up during 360 days following presentation. Cardiac syncope was classified into four groups: bradyarrhythmia, tachyarrhythmia, structural disease and other (cardiopulmonary and great vessels), as recommended in the ESC Syncope Guidelines. All-cause death during 2-years follow-up was the primary outcome.

Results

Among 2025 patients presenting with syncope to the ED, cardiac syncope was the final adjudicated diagnoses in 318 (15.7%) patients. The incidence rate of all-cause death among cardiac syncope patients was 103 cases per 1000 person-years. Bradyarrhythmia was the most frequent primary cause of cardiac syncope (n=146, 45.9%) followed by tachyarrhythmia (n=75, 23.6%), structural disease (n=64, 20.1%) and other cardiac (n=26, 8.2%). Patients were 37% female with a median age of 77 years (IQR 67–83) showing no statistically significant difference between subgroups. Clinical characteristics differed significantly among the four subgroups. E.g. syncope occurred during exercise in 12 patients (8.2%) with bradyarrhythmia, 10 patients (13.3%) with tachyarrhythmia, 16 patients (25%) with structural disease, and 5 patients (19%) with other cardiac (p&lt;0.01). Likely of most importance, long-term mortality differed significantly among the four different cardiac subgroups. The multivariable-adjusted hazard ratios (HR) among patients with bradyarrhythmia, tachyarrhythmia, structural disease and other cardiac as compared to patients with vasovagal syncope, the HR were 1.3 (95% CI 0.7–2.5), 4.6 (95% CI 2.3–9.1), 3.1 (95% CI 1.5–6.4) and 5.9 (95% CI 2.3–15.2), respectively (Figure 1).

Conclusions

Bradyarrhythmia, tachyarrhythmia, and structural cardiac disease are the dominant causes of cardiac syncope. Interestingly, with the appropriate therapy initiated long-term mortality of bradyarrhythmia is comparable to that of vasovagal syncope, while long-term mortality of tachyarrhythmia and structural cardiac disease were substantially increased 3 to 5 fold.

Figure 1. Kaplan-Meier curve

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Swiss National Science Foundation, the Swiss Heart Foundation, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel and the University Hospital Basel.

External validation of a clinical decision rule to identify patients at low risk for acute coronary syndrome who do not need objective coronary artery disease testing

Background

Rapid high-sensitivity cardiac troponin (hs-cTn) based algorithms have substantially improved the early rule-out of acute myocardial infarction (AMI) and thereby facilitated the selection of patients eligible for outpatient management. However, it remains unclear, which patients after rule-out of AMI should still undergo objective anatomic or functional cardiac testing for the detection of relevant coronary artery disease. A pilot study has derived a clinical decision rule for the selection of patients who do not need objective anatomic or functional cardiac testing for coronary artery disease (“No Objective Testing” (NOT) rule).

Purpose

To externally validate the performance of the NOT-rule in a multicentre study.

Methods

Patients presenting to the ED with symptoms suggestive of an acute coronary syndrome (ACS) were enrolled in a large prospective international multicentre study at 12 study sites in five European countries. Two independent cardiologists centrally adjudicated the final diagnosis using all clinical data including cardiac imaging and at least 90-day follow-up. The NOT-rule is applied in patients, in whom a 2h accelerated diagnostic protocol (using hs-cTnI concentrations at 0h/2h and ECG data) has ruled-out AMI and based on clinical variables. In brief, the first rule is a weighted score derived from independent predictors of ACS that classifies patients as low-risk if they score ≤4 points. The second rule was simplified and ruled patients out if they were younger than 50 years, had no history of an AMI or known CAD, and no prescribed nitrates. The third rule equals the second except nitrate use was omitted. Primary objective was the safety and efficacy of the NOT-rules for rule-out of major adverse cardiac events (MACE) including AMI, unstable angina pectoris, urgent or emergency revascularisation or cardiovascular death at 30-days of follow-up. Secondary objective was the safety and efficacy for rule-out of MACE at 2-years.

Results

Out of 3188 enrolled patients, 2162 (68%) had hs-cTnI concentrations at 0h and 2h below the 99th centile as well as a non-diagnostic ECG and were therefore eligible for the analysis. MACE at 30-days occurred in 302 (14%) patients. The second and third rule offered highest safety and efficacy for rule-out of MACE at 30-days. Both identified 492 (23%) patients at low-risk with a sensitivity of 99.7% (95% CI 98.2–99.9%) and a negative predictive value (NPV) of 99.8% (95% CI 98.6–99.9%). One MACE was missed within 30-days (revascularisation of a one-vessel CAD). Sensitivity 98.9% (95% CI 97.1–99.7%) and NPV 99.2% (95% CI 97.8–99.7) were also very high for 1-year MACE, as well as 2-year MACE 98.4% (95% CI 96.5–99.4%) and 98.4% (95% CI 96.5–99.3%), respectively.

Conclusions

The NOT rules proved to be a safe tool that identifies nearly one-fourth of patients at very low risk for MACE, who may not need objective anatomic or functional cardiac testing for coronary artery disease.

Performance of NOT rules

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the KTI, the European Union, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel, the University Hospital Basel

Prognostic value of health-related quality of life in patients with acute dyspnea

Background

Previous studies have shown the prognostic value of health-related quality of life (HRQL) in stable and ambulatory chronic heart failure patients. However, it is unknown whether HRQL can predict all-cause mortality in patients presenting to the emergency department (ED) after acute onset of symptoms. In order to address this unmet need, the aim of this study was to assess the prognostic value of HRQL in patients with acute dyspnea caused by acute heart failure (AHF) and other dyspnea aetiologies for 360-day mortality.

Purpose

To assess prognostic value of HRQL using the generic EQ-5D and visual analogue scale (EQ VAS) in patients with acute dyspnea.

Methods

Basics in Acute Shortness of Breath EvaLuation (BASEL V) is a prospective, multicenter, diagnostic study enrolling adult patients presenting with acute dyspnea to the ED. For this analysis, only patients with a complete set of variables necessary for calculation of EQ-5D (range 0–10; with higher score indicating worse HRQL) and EQ VAS (range 0–100; with 100 being the best imaginable health state) at baseline were included. The endpoint was the prognostic value of EQ-5D and EQ VAS at 360 days of follow-up regarding all-cause death. Prognostic accuracy was calculated using c-statistics. In a cox regression analysis EQ-5D was treated as both, a continuous and categorical variable. Adjustments were made for clinically relevant covariates (age, sex, orthopnoea, edema, level of N-terminal pro-B-type natriuretic peptide (NT-proBNP) at presentation, history of coronary artery disease and chronic obstructive pulmonary disease, diuretics, β-blockers and ACE-inhibitors at discharge).

Results

Among 2605 patients enrolled, 1141 (43,8%) had a complete set of variables allowing the calculation of EQ-5D and EQ VAS. Of these patients 594 (52.1%) had an adjudicated final diagnosis of AHF. 211 (18.5%) patients died within 360 days of follow-up. Median EQ-5D was 3 (interquartile range (IQR) 1.5–5) and median EQ VAS was 50 (IQR 40–70). The prognostic accuracy for 360-day mortality was 0.65 (95% confidence interval ((CI) 0.61–0.69) and 0.58 (95% CI 0.54–0.62) for EQ-5D and EQ VAS, respectively (p=0.002). After combining EQ-5D and EQ VAS in a logistic regression model c-statistics regarding all-cause mortality within 360 days did not improve. The prognostic accuracy of EQ-5D was comparable to that of NT-proBNP (c-statistics 0.69, p=0.385). In an adjusted cox regression analysis the hazard ratio for patients with EQ-5D &gt;4 was 2.2 (95% CI 1.7–2.9; p&lt;0.001).

Conclusions

In patients presenting with acute dyspnea HRQL is a strong prognostic instrument. Independently of the aetiology of the dyspnea the prognostic value of the generic EQ-5D for 360-day mortality is comparable to NT-proBNP. Patients with an EQ-5D &gt;4 are at significantly higher risk for mortality within 360 days.

Figure 1. Prognostic value of HRQL

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, Swiss Heart Foundation

Direct comparison of BNP and NT-proBNP for mortality prediction in patients with acute dyspnea

Background

It is unclear whether BNP or NT-proBNP, their admission or discharge measurement or percentage change during hospitalization are preferable for mortality prediction in patients with acute dyspnea.

Purpose

To directly compare BNP and NT-proBNP regarding their potential in mortality prediction in patients with acute dyspnea and in patients with dyspnea due to AHF.

Methods

In a prospective multicenter diagnostic study the presence of AHF was centrally adjudicated by two independent cardiologists among patients presenting with acute dyspnea. The levels of BNP and NT-proBNP were measured at presentation and discharge. Patients were stratified according to their natriuretic peptide response (responders vs. non-responders: natriuretic peptide decrease ≥25% vs. &lt;25% before discharge). Prognostic accuracy for 720-day mortality was quantified using the area under the receiver-operating-characteristic curve (AUC). Cox proportional hazard models were constructed to identify significant predictors for 720-day mortality.

Results

Among 1156 patients presenting with acute dyspnea, 353 (30.5%) died within 720 days of follow-up. Prognostic accuracy for death at 720 days was significantly higher for discharge compared to admission measurements for BNP (AUC 0.750 vs. 0.711, p&lt;0.001) and NT-proBNP (AUC 0.769 vs. 0.720, p&lt;0.001). When directly comparing discharge measurements, NT-proBNP levels exhibited a significantly higher accuracy (p=0.013). 632 (54.6%) and 600 (51.9%) patients were BNP and NT-proBNP non-responders, respectively. Among BNP and NT-proBNP non-responders 202 (32%) and 207 (34.5%) patients died within 720 days of follow-up. After adjusting for common covariates NTproBNP response was the strongest predictor for 720-day mortality in a Cox regression model (Hazard ratio for NT-proBNP non-responders: 2.096 (95% CI 1.550–2.835), p&lt;0.001). Results were confirmed in a sensitivity analysis of 687 (59.4%) patients with adjudicated AHF.

Conclusion

Percentage change of NT-proBNP during hospitalization seems to be the strongest predictor for long-term mortality in patients with acute dyspnea in general and in those with dyspnea due to AHF in particular.

ROC curve for direct comparison

Funding Acknowledgement

Type of funding source: None

External validation of a suggested extension of the ESC 0/1h-algorithm for early rule out of myocardial infarction

Background

The European Society of Cardiology (ESC) high sensitivity cardiac troponin T 0/1h-algorithm has substantially improved the management of patients with suspected acute myocardial infarction (AMI) by triaging about 75% of patients to rapid rule-out and/or rapid rule-in. However, about 25% of patients remain in the “observe-zone”, and the optimal management of these patients is unknown. Recently, a pilot single center study with a low prevalence of AMI suggested that an absolute change of less than 7ng/L between the 0h and 3h hs-cTnT concentration would allow to help in the evaluation of patients in the observe-zone and allow triage towards rule-out with very high negative predictive value [NPV].

Purpose

To externally validate this suggested modification of the ESC 0/1h-algorithm for early rule out of AMI.

Methods

In an ongoing multicentre international study, we prospectively enrolled unselected patients presenting to the emergency department with symptoms suggestive of MI. Final diagnoses were centrally adjudicated by two independent cardiologists using all available medical records obtained during clinical care including 90 day follow-up information and cardiac imaging. High sensitivity-cTnT (Elecsys) concentrations were measured at presentation and after 1 and 3 hours. The primary outcome was safety, quantified by the sensitivity and NPV for early rule out of NSTEMI.

Results

Among 1633 enrolled patients with available 0, 1 and 3h hs-cTnT concentrations, NSTEMI was the adjudicated final diagnosis in 337 (20.6%) patients. The ESC 0/1h-algorithm ruled out 918 (56.2%) patients, with a sensitivity of 98.8% (95% confidence interval [CI], 97.0–99.5) and a NPV of 99.6% (95% CI, 98.9–99.8). A total of 428 patients (26.2%) remained in the observe zone. After applying the suggested 0–3 hour absolute change cut-off criteria of 7ng/L, 393 (92.0%) additional patients from the observe zone were triaged towards ruled out. However, the safety of this triage step was poor with 62 patients with NSTEMI missed, resulting in a sensitivity of 33.3% and a NPV of 84.2% for rule-out.

Conclusions

The suggested 0/3h absolute change cut-off of 7ng/L for patients remaining in the observe zone of the ESC 0/1h-algorithm does NOT allow safe rule-out of AMI and should therefore NOT be implemented into routine clinical care.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Swiss National Science Foundation, the Swiss Heart Foundation, the Stiftung für kardiovaskuläre Forschung Basel, the University of Basel and the University Hospital Basel

Quantifying inflammation using interleukin-6 for improved phenotyping and risk stratification in acute heart failure

Background

Acute heart failure (AHF) is the most common cause of hospital admission and continues to have unacceptable high rates of mortality and morbidity. In contrast to acute myocardial infarction, the pathophysiology of AHF is incompletely understood and risk-prediction is poorly defined.

Aim

We aimed to quantify systemic inflammation to assess its possible role in the pathophysiology and risk stratification of patients with AHF.

Methods

Using a novel Interleukin-6 immunoassay with unprecedented sensitivity (limit of detection 0.01ng/l) we quantified systemic inflammation in unselected patients presenting with acute dyspnea to the emergency department in a multicenter study. Plasma concentrations of NT-proBNP (open label) and Interleukin-6 (blinded) were measured at presentation and at discharge. The final diagnosis of AHF and the AHF phenotype were adjudicated by two independent cardiologists. 1-year mortality was the prognostic endpoint.

Results

Among 2042 patients, 1026 (50.2%) had an adjudicated diagnosis of AHF. Interleukin-6 concentrations were significantly higher in AHF patients compared to patients with other causes of dyspnoea (11.2 [6.1–26.5] ng/l vs 9.0 [3.2–32.3] ng/l, p&lt;0.0005). Among patients with AHF Interleukin-6 concentrations were elevated (&gt;4.45ng/l) in 83.7% of them. Among the different AHF phenotypes, Interleukin-6 concentrations were highest in patients with cardiogenic shock (25.7 [14.0–164.2] ng/l) and lowest in patients with hypertensive HF (9.3 [4.8–21.6] ng/l, p=0.001). Inflammation as quantified by Interleukin-6 was a strong predictor of 1-year mortality both in AHF as well as in other causes of acute dyspnea (Figure). During in-hospital treatment Interleukin-6 concentrations significantly decreased in AHF patients. However, changes in the extend of systemic inflammation (delta Interleukin-6) were poorly correlated with changes in hemodynamic stress as quantified by NT-proBNP (delta NT-proBNP, Φc=0.11, p=0.004).

Conclusions

An unexpectedly high percentage of patients with AHF have subclinical systemic inflammation that can be quantified by Interleukin-6, which seems to contribute to the AHF phenotype and to the risk of death.

Kaplan Meier curves for mortality

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Swiss National Science Foundation, Swiss Heart Foundation, European Union, Stiftung für kardiovaskuläre Forschung Basel, University of Basel, University Hospital Basel

P2617Activity of the adrenomedullin system to personalize post-discharge treatment in acute heart failure

Objectives

Activity of the adrenomedullin system was quantified by using bioactive-adrenomedullin (bio-ADM), the biologically active moiety, and midregional proadrenomedullin (MR-proADM), a prohormone fragment, to 1) identify acute heart failure (AHF) phenotypes with disproportional benefit or harm from specific treatments at hospital discharge, 2) predict mortality, and 3) compare the prognostic utility of both biomarkers.

Methods

This prospective multicentre study using central adjudication of AHF measured bio-ADM in all patients and MR-proADM in a predefined subgroup in a blinded fashion on admission. Both biomarkers were measured at discharge as well. Interaction with specific treatments at hospital discharge and the biomarkers' prognostic utility during 365 days' follow-up were assessed.

Results

Among 1,886 patients with adjudicated AHF, 514 patients (27.3%) died during the 365 days' follow-up. Patients with bio-ADM plasma concentrations above the median were at a much higher risk of death (HR 1.87, 95% CI 1.57–2.24; p<0.001). After adjusting for age, creatinine plasma concentrations, and medical treatment at discharge, those patients derived disproportional benefit if treated with diuretics and/or angiotensin-converting-enzyme inhibitors/angiotensin receptor blocker (interaction p-values <0.05). These findings were confirmed only for the diuretics treatment when quantifying the adrenomedullin system using MR-proADM plasma concentrations (n=764). For predicting mortality, both biomarkers performed well and MR-proADM had a higher predictive accuracy as compared to bio-ADM (p<0.001).

Table 1. Interaction p-values in multivariate models using a cox proportional hazard analysis for predicting all-cause mortality at 365 days including age, bio-ADM or MR-proADM, creatinine at discharge, and medication at discharge Diuretics ACE inhibitors or ARB Beta blockers Aldosterone antagonists lg bio-ADM*, ng/l <0.001 0.011 0.760 0.175 lg bio-ADM†, ng/l <0.001 0.020 0.807 0.396 lg MR-proADM*, nmol/l 0.031 0.095 0.169 0.441 lg MR-proADM†, nmol/l 0.001 0.126 0.741 0.272 *At admission; †at discharge. ACE: Angiotensin-converting-enzyme; ARBs: Angiotensin receptor blocker; bio-ADM: bioactive adrenomedullin; MR-proADM: midregional proadrenomedullin.

Figure 1

Conclusion

Quantifying the activity of the adrenomedullin system helps to personalize post-discharge treatment and risk-prediction in AHF.

Acknowledgement/Funding

Swiss National Science Foundation, Swiss Heart Foundation, University of Base, Sphingotec

2409ALERT-CS - Development of an ECG-based cardiac syncope risk calculator

Background

Syncope is a common symptom with rising incidence, often leading to emergency department (ED) visits. Early determination of diagnosis is often difficult in patients with syncope and there is an unmet clinical need for tools that can support physicians in their decision making. We hypothesized that an electrocardiogram (ECG)-based cardiac syncope risk calculator might create a simple and attractive clinical decision tool for the diagnosis and risk stratification of patients with syncope.

Methods

Based on a large prospective diagnostic international multicenter study enrolling patients who presented to the ED with syncope, we derived a cardiac syncope risk calculator by penalized stepwise backward-selection and multivariable logistic regression utilizing predefined ECG criteria. Primary diagnostic endpoint was cardiac syncope, as adjudicated by two independent physicians taking into account all available information including cardiac work-up and 12-month follow-up. Major adverse cardiac events (MACE) including life-threatening arrhythmias, myocardial infarction, pulmonary embolism, stroke, transient ischemic attack, valvular surgery, and death within 30 days were the prognostic endpoint.

Results

Median age in our cohort was 71 years and 40% of patients were women. Of all 2007 patients enrolled, 1696 patients were eligible for the prognostic analysis and 1550 patients were eligible for the diagnostic analysis.

We identified seven ECG criteria (rhythm, heart rate, corrected QT-interval, ST-segment depression, atrioventricular-block, bundle-branch-block and ventricular extrasystole/non-sustained ventricular tachycardia) as significant predictors for cardiac syncope and combined them into the bAseL Ecg Risk calculaTor for Cardiac Syncope (ALERT-CS). Diagnostic accuracy for cardiac syncope, as quantified by the area under the receiver operating characteristic curve (AUC), was high (AUC 0.80, 95%-confidence interval (CI) 0.77 to 0.83), and significantly higher compared to that of the EGSYS score (AUC 0.73, 95%-CI 0.70 to 0.76, p<0.001). Prognostic verification of the ALERT-CS to predict 30-day overall MACE showed similar accuracy (AUC 0.75, 95%-CI 0.71 to 0.79).

Comparison of diagnostic discrimination

Conclusion

Combining seven ECG criteria within a simple risk calculator for cardiac syncope may aid physicians in the diagnosis and risk stratification of patients presenting to the ED with syncope.

Acknowledgement/Funding

Swiss National Science Foundation, Swiss Heart Foundation, Cardiovascular Research Foundation Basel, University Basel

P792Cardiac myosin-binding protein C for the diagnosis and long-term prognosis of acute heart failure

Background

Cardiac myosin-binding protein C (cMyC) is a novel biomarker quantifying cardiac injury. Its utility for the diagnosis, prognosis, and therapy guidance in acute heart failure (AHF) is unclear.

Methods

In a prospective diagnostic multicentre study, unselected patients presenting with acute dyspnoea to the emergency department were enrolled. cMyC, high-sensitive cardiac troponin T (hs-cTnT), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) plasma concentrations were measured. Two independent cardiologists/internists centrally adjudicated the final diagnosis using all individual patient's information. Co-primary outcome measures were cMyC's: diagnostic safety and efficacy; prognostic accuracy.

Results

Among 1,330 recruited patients, 247 from an AHF substudy were not included in the diagnostic analysis. Accordingly, 548 patients (51%) in this analysis had an adjudicated diagnosis of AHF. For the rapid rule-out of AHF, the cMyC cut-off concentration at 16 ng/L achieved a sensitivity of 95% (95% CI, 93–97%), a negative predictive value of 88% (95% CI, 84–92%), and allowed to rule-out 21% of the patients. Correspondingly, cMyC's efficacy and safety in the triage of AHF were slightly lower than NT-proBNP's. Of the 790 AHF patients in the prognostic analysis, 222 (28%) died during the 360 days' follow-up. Patients with cMyC plasma concentrations above the median had significantly shorter mean time to death (274 versus 320 days, p=0.001). Compared to hs-cTnT and discharge NT-proBNP, cMyC showed non-inferior prognostic accuracy. No significant interactions between cMyC and cardiac medical therapies at discharge in predicting 360 days survival were present.

Conclusion

cMyC performs well in the rapid triage and prognosis of AHF.

Acknowledgement/Funding

European Union, Swiss National Science Foundation, Swiss Heart Foundation, Cardiovascular Research Foundation Basel, University Hospital of Basel

P3532Quantifying hemodynamic cardiac stress and cardiomyocyte injury in hypertensive and normotensive acute heart failure

Background

Better characterization of the different pathophysiological mechanisms involved in normotensive and hypertensive acute heart failure (AHF) might help to develop novel individualized treatment strategies.

Methods

The extent of hemodynamic cardiac stress and cardiomyocyte injury was quantified by measuring B-type natriuretic peptide (BNP) as well as high-sensitive cardiac troponin T (hs-cTnT) in 1,152 unselected patients presenting with AHF to the emergency department (derivation cohort). Systolic blood pressure (SBP) of 90 - 140 mmHg at presentation was used to define normotensive AHF. Findings regarding hemodynamic cardiac stress and cardiomyocyte injury were validated in a second independent AHF cohort (validation cohort; n=324).

Results

In the derivation cohort 667 (58%) patients had hypertensive AHF. Hemodynamic cardiac stress, as quantified by BNP levels, was significantly higher in normotensive AHF as compared to hypertensive AHF (1,105 pg/mL versus 827 pg/mL, p<0.001). In addition, the extent of cardiomyocyte injury, as quantified by hs-cTnT, was significantly higher in normotensive AHF as compared to hypertensive AHF (41 ng/L versus 33 ng/L, p<0.001). These findings were confirmed in the validation cohort.

Table 1. Cardiac stress and myocardial necrosis as quantified by BNP and hs-cTnT plasma concentrations Overall Hypertensive AHF Normotensive AHF p-value BNP in pg/ml, median (IQR) 974 (536–1,712) 827 (448–1,419) 1,105 (611–1,956) <0.001 hs-cTnT in ng/L, median (IQR) 37 (22–67) 33 (19–59) 41 (24–71) <0.001 BNP = B-type natriuretic peptide; hs-cTnT = high-sensitivity cardiac Troponin T; IQR = inter-quartile range.

Figure 1

Conclusion

Biomarker profiling revealed that the extent of hemodynamic stress and cardiomyocyte injury is different in patients with normotensive and hypertensive AHF. This characterization could help to understand AHF phenotypes better, which in turn may lead to more specific management in future, thus improving the dismal prognosis in these patients.

Acknowledgement/Funding

European Union, Swiss National Science Foundation, Swiss Heart Foundation, Cardiovascular Research Foundation Basel, University of Basel

P1765Hyperacute T-wave in the early diagnosis of acute myocardial infarction

Background

The clinical significance of prominent T-waves, also referred as hyperacute T-waves, in the early diagnosis of acute myocardial infarction (AMI) is unknown.

Purpose

To evaluate the clinical utility of hyperacute T-waves in the early diagnosis of AMI.

Methods

In a prospective diagnostic study enrolling patients presenting to the emergency department (ED) with symptoms suggestive of AMI, final diagnoses were adjudicated by two independent cardiologists based on clinical information including cardiac imaging. Electronic electrocardiogram data were available in 2946 consecutive patients. Patients with left ventricular hypertrophy, complete left bundle branch block or pacemaker were excluded from further analysis. In the remaining 2382 patients, the T-wave amplitude was automatically derived from the standard 10 seconds 12-lead ECG recorded at presentation to the ED using an established algorithm.

Results

Median (IQR) time from chest pain onset (CPO) to ED presentation was 5 (IQR [2.5, 12.2]) hours. A total of 219 patients (9%) presented to the ED within 1h or less from CPO. AMI was the final diagnosis in 18% (NSTEMI in 15%, STEMI in 3%) of patients. High T-wave amplitude in leads AVF, III and V1 were associated with AMI. Optimal cut-offs were derived to achieve a predefined positive predictive value (PPV) of at least 75%. These criteria were 473mV, 357mV and 483mV for AVF, III and V1, respectively. With these cut-offs 1.4%, 4.2% and 0.9% of all patients with AMI were detected and specificity was 99.9% (95% CI [99.7%, 100%]), 99.7% (95% CI [99.4%, 99.9%]) and 99.9% (95% CI [99.8%, 100%]). However, majority of the patients with AMI correctly identified by the hyperacute T-wave had also significant ST-element elevations (AVF: 5 out of 6; [83.3%]; III: 10 out of 18 [56%]; V1:1 out of 4; [25%]).

Conclusion

In patients presenting to the ED with symptoms suggestive of AMI, only leads AVF, III and V1 showed hyperacute T-waves with high PPV. However, incidence of this finding is very low. In addition, majority of the cases correctly identified by hyperacute T-waves also had concomitant ST-segment elevations. Therefore, hyperacute T-waves have only very limited utility in the early diagnosis of AMI in the ED.

Acknowledgement/Funding

Swiss National Science Foundation, the Swiss Heart Foundation, the KTI, the European Union,the Stiftung für kardiovaskuläre Forschung Basel

P1656Incremental value of interleukin-6 and C-reactive protein to the MEESSI acute heart failure risk score

Background

The MEESSI-acute heart failure (AHF) risk score has high accuracy in the prediction of 30-day mortality in patients presenting with AHF and may be considered the current gold standard for this indication.

Purpose

As the original MEESSI model does not include measurements of inflammatory biomarkers, the impact of interleukin-6 or C-reactive protein (CRP) on the model's goodness of fit is unknown.

Methods

In a prospective multicenter diagnostic study the presence of AHF was centrally adjudicated by two independent cardiologists among patients presenting with acute dyspnea to the ED. The MEESSI-AHF risk score was calculated using a recalibrated model containing 12 independent risk factors. The incremental value of interleukin-6 and CRP was examined by the use of logistic regression analysis and enter method variable selection with an entry criterion of p<0.05. Goodness of fit tests were performed to measure the updated model's discrimination and calibration.

Results

In 1247 patients with adjudicated AHF, the MEESSI-AHF risk score was calculated. Of these, 1113 patients (89.3%) had available measurements of interleukin-6 and CRP. In the logistic regression analysis both biomarkers had a highly significant impact on the MEESSI model (p<0.001, respectively). Compared to the original MEESSI-Model (c-statistic, 0.79 (95% CI, 0.75–0.83)) the addition of interleukin-6 (c-statistic, 0.81 (95% CI, 0.77–0.85)) or CRP (c-statistic, 0.83 (95% CI, 0.79–0.86)) significantly improved the model's discrimination (p=0.022 and p=0.011, respectively). When assessing the cumulative mortality, the gradient in 30-day mortality over six predefined risk groups was increased by addition of interleukin-6 or CRP. 30-day mortality rates in the lowest and highest risk groups of the original model were 0.4% and 32.5% compared to 0% and 34.9% in the model updated with interleukin-6 and 0.6% and 37.6% in the model updated with CRP. All compared models showed good overall calibration (Hosmer-Lemeshow p=0.302 (original model), p=0.136 (model updated by interleukin-6) and p=0.902 (model updated by CRP)).

Discrimination original_updated

Conclusion

There is significant incremental value of interleukin-6 and CRP to the MEESSI score as indicated by the improved goodness of fit compared to the original model.

Acknowledgement/Funding

European Union, the Swiss National Science Foundation, the Swiss Heart Foundation, the Cardiovascular Research Foundation Basel,