External validation of the 0/1h-algorithm and derivation of a 0/2h-algorithm using a new point-of-care Hs-cTnI assay.

BACKGROUND: The high-sensitivity cardiac troponin (hs-cTn) I point-of-care (POC) hs-cTnI-PATHFAST assay has recently become clinically available. METHODS: We aimed to externally validate the hs-cTnI-PATHFAST 0/1h-algorithm recently developed for the early diagnosis of non-ST-segment-elevation myocardial infarction (NSTEMI) and derive and validate a 0/2-algorithm in patients presenting to the emergency department with acute chest discomfort included in a multicenter diagnostic study. Two independent cardiologists centrally adjudicated the final diagnoses using all the clinical and study-specific information available including serial measurements of hs-cTnI-Architect. RESULTS: Among 1,532 patients (median age 60 years, 33% [n = 501] women), NSTEMI was the final diagnosis in 13%. External validation of the hs-cTnI-PATHFAST 0/1h-algorithm showed very high negative predictive value (NPV; 100% [95%CI, 99.5%-100%]) and sensitivity 100% (95%CI, 98.2%-100%) for rule-out of NSTEMI. Positive predictive value (PPV) and specificity for rule-in of NSTEMI were high (74.9% [95%CI, 68.3%-80.5%] and 96.4% [95%CI, 95.2%-97.3%], respectively). Among 1,207 patients (median age 61 years, 32% [n = 391] women) available for the derivation (n = 848) and validation (n = 359) of the hs-cTnI-PATHFAST 0/2h-algorithm, a 0h-concentration <3 ng/L or a 0h-concentration <4 ng/L with a 2h-delta <4ng/L ruled-out NSTEMI in 52% of patients with a NPV of 100% (95%CI, 98-100) and sensitivity of 100% (95%CI, 92.9%-100%) in the validation cohort. A 0h-concentration ≥90ng/L or a 2h-delta ≥ 55ng/L ruled-in 38 patients (11%): PPV 81.6% (95%CI, 66.6-90.8), specificity 97.7% (95%CI, 95.4-98.9%). CONCLUSIONS: The POC hs-cTnI-PATHFAST assay allows rapid and effective rule-out and rule-in of NSTEMI using both a 0/1h- and a 0/2h-algorithm with high NPV/sensitivity for rule-out and high PPV/specificity for rule-in. CLINICAL TRIAL REGISTRATION: NCT00470587.

Diagnostic discrimination of a novel high-sensitivity cardiac troponin I assay and derivation/validation of an assay-specific 0/1h-algorithm.

BACKGROUND: We aimed to assess the diagnostic utility of the Dimension EXL LOCI High-Sensitivity Troponin I (hs-cTnI-EXL) assay. METHODS: This multicenter study included patients with chest discomfort presenting to the emergency department. Diagnoses were centrally and independently adjudicated by two cardiologists using all available clinical information. Adjudication was performed twice including serial measurements of high-sensitivity cardiac troponin (hs-cTn) I-Architect (primary analysis) and serial measurements of hs-cTnT-Elecsys (secondary analysis) in addition to the clinically used (hs)-cTn. The primary objective was to assess and compare the discriminatory performance of hs-cTnI-EXL, hs-cTnI-Architect and hs-cTnT-Elecsys for acute myocardial infarction (MI). Furthermore, we derived and validated a hs-cTnI-EXL-specific 0/1h-algorithm. RESULTS: Adjudicated MI was the diagnosis in 204/1454 (14%) patients. The area under the receiver operating characteristics curve for hs-cTnI-EXL was 0.94 (95%CI, 0.93-0.96), and comparable to hs-cTnI-Architect (0.95; 95%CI, 0.93-0.96) and hs-cTnT-Elecsys (0.93; 95%CI, 0.91-0.95). In the derivation cohort (n = 813), optimal criteria for rule-out of MI were <9ng/L at presentation (if chest pain onset >3h) or <9ng/L and 0h-1h-change <5ng/L, and for rule-in ≥160ng/L at presentation or 0h-1h-change ≥100ng/L. In the validation cohort (n = 345), these cut-offs ruled-out 56% of patients (negative predictive value 99.5% (95%CI, 97.1-99.9), sensitivity 97.8% (95%CI, 88.7-99.6)), and ruled-in 9% (positive predictive value 83.3% (95%CI, 66.4-92.7), specificity 98.3% (95%CI, 96.1-99.3)). Secondary analyses using adjudication based on hs-cTnT measurements confirmed the findings. CONCLUSIONS: The overall performance of the hs-cTnI-EXL was comparable to best-validated hs-cTnT/I assays and an assay-specific 0/1h-algorithm safely rules out and accurately rules in acute MI. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number, NCT00470587.

Effect of Flu Vaccination on Severity and Outcome of Heart Failure Decompensations.

OBJECTIVE: To investigate the relationship of seasonal flu vaccination with the severity of decompensation and long-term outcomes of patients with heart failure (HF). METHODS: We analyzed 6147 consecutively enrolled patients with decompensated HF who presented to 33 Spanish emergency departments (EDs) during January and February of 2018 and 2019, grouped according to seasonal flu vaccination status. The severity of HF decompensation was assessed by the Multiple Estimation of Risk Based on the Emergency Department Spanish Score in Patients With Acute Heart Failure (MEESSI-AHF) + MEESSI scale, need of hospitalization and in-hospital all-cause mortality. The long-term outcomes analyzed were 90-day postdischarge adverse events and 90-day all-cause death. Associations between vaccination, HF decompensation severity and long-term outcomes were explored by unadjusted and adjusted logistic and Cox regressions by using 14 covariables that could act as potential confounders. RESULTS: Overall median (IQR) age was 84 (IQR = 77-89) years, and 56% were women. Vaccinated patients (n = 1139; 19%) were older, had more comorbidities and had worse baseline status, as assessed by New York Heart Association class and Barthel index, than did unvaccinated patients (n = 5008; 81%). Infection triggering decompensation was more common in vaccinated patients (50% vs 41%; P < 0.001). In vaccinated and unvaccinated patients, high or very-high risk decompensation was seen in 21.9% and 21.1%; hospitalization occurred in 72.5% and 73.7%; in-hospital mortality was 7.4% and 7.0%; 90-day postdischarge adverse events were 57.4% and 53.2%; and the 90-day mortality rate was 15.8% and 16.6%, respectively, with no significant differences between cohorts. After adjusting, vaccinated decompensated patients with HF had decreased odds for hospitalization (OR = 0.823, 95%CI = 0.709-0.955). CONCLUSION: In patients with HF, seasonal flu vaccination is associated with less severe decompensations.

Hyperacute T Wave in the Early Diagnosis of Acute Myocardial Infarction.

STUDY OBJECTIVE: The diagnostic performance of T-wave amplitudes for the detection of myocardial infarction is largely unknown. We aimed to address this knowledge gap. METHODS: T-wave amplitudes were automatically measured in 12-lead ECGs of patients presenting with acute chest discomfort to the emergency department within a prospective diagnostic multicenter study. The final diagnosis was centrally adjudicated by 2 independent cardiologists. Patients with left ventricular hypertrophy, complete left bundle branch block, or paced ventricular depolarization were excluded. The performance for lead-specific 95th-percentile thresholds were reported as likelihood ratios (lr), specificity, and sensitivity. RESULTS: Myocardial infarction was the final diagnosis in 445 (18%) of 2457 patients. In most leads, T-wave amplitudes tended to be greater in patients without myocardial infarction than those with myocardial infarction, and T-wave amplitude exceeding the 95th percentile had positive and negative lr close to 1 or with confidence intervals (CIs) crossing 1. The exceptions were leads III, aVR, and V1, which had positive lrs of 3.8 (95% CI, 2.7 to 5.3), 4.3 (95% CI, 3.1 to 6.0) and 2.0 (95% CI, 1.4 to 2.9), respectively. These leads normally have inverted T waves, so T-wave amplitude exceeding the 95th percentile reflects upright rather than increased-amplitude hyperacute T waves. CONCLUSION: Hyperacute T waves, when defined as increased T-wave amplitude exceeding the 95th percentile, did not provide useful information in diagnosing myocardial infarction in this sample.

International Validation of the Canadian Syncope Risk Score : A Cohort Study.

BACKGROUND: The Canadian Syncope Risk Score (CSRS) was developed to predict 30-day serious outcomes not evident during emergency department (ED) evaluation. OBJECTIVE: To externally validate the CSRS and compare it with another validated score, the Osservatorio Epidemiologico della Sincope nel Lazio (OESIL) score. DESIGN: Prospective cohort study. SETTING: Large, international, multicenter study recruiting patients in EDs in 8 countries on 3 continents. PARTICIPANTS: Patients with syncope aged 40 years or older presenting to the ED within 12 hours of syncope. MEASUREMENTS: Composite outcome of serious clinical plus procedural events (primary outcome) and the primary composite outcome excluding procedural interventions (secondary outcome). RESULTS: Among 2283 patients with a mean age of 68 years, the primary composite outcome occurred in 7.2%, and the composite outcome excluding procedural interventions occurred in 3.1% at 30 days. Prognostic performance of the CSRS was good for both 30-day composite outcomes and better compared with the OESIL score (area under the receiver-operating characteristic curve [AUC], 0.85 [95% CI, 0.83 to 0.88] vs. 0.74 [CI, 0.71 to 0.78] and 0.80 [CI, 0.75 to 0.84] vs. 0.69 [CI, 0.64 to 0.75], respectively). Safety of triage, as measured by the frequency of the primary composite outcome in the low-risk group, was higher using the CSRS (19 of 1388 [0.6%]) versus the OESIL score (17 of 1104 [1.5%]). A simplified model including only the clinician classification of syncope (cardiac syncope, vasovagal syncope, or other) variable at ED discharge-a component of the CSRS-achieved similar discrimination as the CSRS (AUC, 0.83 [CI, 0.80 to 0.87] for the primary composite outcome). LIMITATION: Unable to disentangle the influence of other CSRS components on clinician classification of syncope at ED discharge. CONCLUSION: This international external validation of the CSRS showed good performance in identifying patients at low risk for serious outcomes outside of Canada and superior performance compared with the OESIL score. However, clinician classification of syncope at ED discharge seems to explain much of the performance of the CSRS in this study. The clinical utility of the CSRS remains uncertain. PRIMARY FUNDING SOURCE: Swiss National Science Foundation & Swiss Heart Foundation.

Prevalence, Related Factors and Association of Left Bundle Branch Block With Prognosis in Patients With Acute Heart Failure: a Simultaneous Analysis in 3 Independent Cohorts.

OBJECTIVES: To determine the prevalence, characteristics and association with prognosis of left bundle branch block (LBBB) in 3 different cohorts of patients with acute heart failure (AHF). METHODS AND RESULTS: We retrospectively analyzed 12,950 patients with AHF who were included in the EAHFE (Epidemiology Acute Heart Failure Emergency), RICA (National Heart Failure Registry of the Spanish Internal Medicine Society), and BASEL-V (Basics in Acute Shortness of Breath Evaluation of Switzerland) registries. We independently analyzed the relationship between baseline and clinical characteristics and the presence of LBBB and the potential association of LBBB with 1-year all-cause mortality and a 90-day postdischarge combined endpoint (Emergency Department reconsultation, hospitalization or death). The prevalence of LBBB was 13.5% (95% confidence interval: 12.9%-14.0%). In all registries, patients with LBBB more commonly had coronary artery disease and previous episodes of AHF, were taking chronic spironolactone treatment, had lower left ventricular ejection fraction and systolic blood pressure values and higher NT-proBNP levels. There were no differences in risk for patients with LBBB in any cohort, with adjusted hazard ratios (95% confidence interval) for 1-year mortality in EAHFE/RICA/BASEL-V cohorts of 1.02 (0.89-1.17), 1.15 (0.95-1.38) and 1.32 (0.94-1.86), respectively, and for 90-day postdischarge combined endpoint of 1.00 (0.88-1.14), 1.14 (0.92-1.40) and 1.26 (0.84-1.89). These results were consistent in sensitivity analyses. CONCLUSIONS: Less than 20% of patients with AHF present LBBB, which is consistently associated with cardiovascular comorbidities, reduced left ventricular ejection fraction and more severe decompensations. Nonetheless, after taking these factors into account, LBBB in patients with AHF is not associated with worse outcomes.

Soluble urokinase plasminogen activator receptor and functionally relevant coronary artery disease: a prospective cohort study.

BACKGROUND: Soluble urokinase plasminogen activator receptor (suPAR) is an emerging biomarker associated with anatomical CAD burden and cardiovascular outcomes including myocardial infarction (MI) and death. We aimed to validate previous findings of the prognostic value of suPAR and to evaluate its diagnostic potential for functional relevant CAD (fCAD). METHODS: Consecutive patients with suspected fCAD were enrolled. Adjudication of fCAD was performed blinded to suPAR concentrations by myocardial perfusion single-photon emission tomography (MPI-SPECT) and coronary angiography. Prognostic outcome measures included all-cause death, cardiovascular death, and incident MI during 2-year follow-up. RESULTS: Among consecutive 968 patients, suPAR concentrations were higher in patients with fCAD compared to those without (3.45 vs. 3.20 ng/mL, p = 0.007), but did not provide acceptable diagnostic accuracy (area under the curve [AUC]: 0.56, 95%CI 0.52-0.60). SuPAR correlated with high-sensitivity cardiac-troponin T (Spearman's rho (ρ) 0.393, p < 0.001), NT-proBNP (ρ = 0.327, p < 0.001), age (ρ = 0.364, p < 0.001) and very weakly with coronary atherosclerosis (ρ = 0.123, p < 0.001). Prognostic discrimination of suPAR was moderate for cardiovascular death (AUC = 0.72, 95%CI 0.62-0.81) and all-cause death (AUC = 0.72, 95%CI 0.65-0.79) at 2-years. SuPAR remained a significant predictor for all-cause death in multivariable Cox regression (HR = 1.96, p = 0.001). CONCLUSIONS: SuPAR was an independent predictor of all-cause death, without diagnostic utility for fCAD. CLINICAL TRIAL REGISTRATION: NCT01838148.

Performance of the ESC 0/2h-algorithm using high-sensitivity cardiac troponin I in the early diagnosis of myocardial infarction.

The 2020 guidelines of the European Society of Cardiology (ESC) recommend a novel ESC 0/2h-algorithm as the preferred alternative to the ESC 0/1h-algorithm in the early triage for rule-out and/or rule-in of Non-ST-segment-elevation myocardial infarction (NSTEMI). The aim was to prospectively validate the performance of the ESC 0/2h-algorithm using the high-sensitivity cardiac troponin I (hs-cTnI) assay (ARCHITECT) in an international, multicenter diagnostic study enrolling patients presenting with acute chest discomfort to the emergency department.

Using High-Sensitivity Cardiac Troponin for the Exclusion of Inducible Myocardial Ischemia in Symptomatic Patients: A Cohort Study.

Background: The optimal noninvasive method for surveillance in symptomatic patients with stable coronary artery disease (CAD) is unknown. Objective: To apply a novel approach using very low concentrations of high-sensitivity cardiac troponin I (hs-cTnI) for exclusion of inducible myocardial ischemia in symptomatic patients with CAD. Design: Prospective diagnostic cohort study. (ClinicalTrials.gov: NCT01838148). Setting: University hospital. Patients: 1896 consecutive patients with CAD referred with symptoms possibly related to inducible myocardial ischemia. Measurements: Presence of inducible myocardial ischemia was adjudicated using myocardial perfusion imaging with single-photon emission computed tomography, as well as coronary angiography and fractional flow reserve measurements where available. Staff blinded to adjudication measured circulating hs-cTn concentrations. An hs-cTnI cutoff of 2.5 ng/L, derived previously in mostly asymptomatic patients with CAD, was assessed. Predefined target performance criteria were at least 90% negative predictive value (NPV) and at least 90% sensitivity for exclusion of inducible myocardial ischemia. Sensitivity analyses were based on measurements with an hs-cTnT assay and an alternative hs-cTnI assay with even higher analytic sensitivity (limit of detection, 0.1 ng/L). Results: Overall, 865 patients (46%) had inducible myocardial ischemia. The hs-cTnI cutoff of 2.5 ng/L provided an NPV of 70% (95% CI, 64% to 75%) and a sensitivity of 90% (CI, 88% to 92%) for exclusion of inducible myocardial ischemia. No hs-cTnI cutoff reached both performance characteristics predefined as targets. Similarly, using the alternative assays for hs-cTnI or hs-cTnT, no cutoff achieved the target performance: hs-cTnT concentrations less than 5 ng/L yielded an NPV of 66% (CI, 59% to 72%), and hs-cTnI concentrations less than 2 ng/L yielded an NPV of 68% (CI, 62% to 74%). Limitation: Data were generated in a large single-center diagnostic study using central adjudication. Conclusion: In symptomatic patients with CAD, very low hs-cTn concentrations, including hs-cTnI concentrations less than 2.5 ng/L, do not generally allow users to safely exclude inducible myocardial ischemia. Primary Funding Source: European Union, Swiss National Science Foundation, Kommission für Technologie und Innovation (Innosuisse), Swiss Heart Foundation, Cardiovascular Research Foundation Basel, University of Basel, University Hospital Basel, Roche, Abbott, and Singulex.

B-Type Natriuretic Peptides and Cardiac Troponins for Diagnosis and Risk-Stratification of Syncope.

BACKGROUND: The utility of BNP (B-type natriuretic peptide), NT-proBNP (N-terminal proBNP), and hs-cTn (high-sensitivity cardiac troponin) concentrations for diagnosis and risk-stratification of syncope is incompletely understood. METHODS: We evaluated the diagnostic and prognostic accuracy of BNP, NT-proBNP, hs-cTnT, and hs-cTnI concentrations, alone and against those of clinical assessments, in patients >45-years old presenting with syncope to the emergency department in a prospective diagnostic multicenter study. BNP, NT-proBNP, hs-cTnT and hs-cTnI concentrations were measured in a blinded fashion. Cardiac syncope, as adjudicated by 2 physicians based on all information available including cardiac work-up and 1-year follow-up, was the diagnostic end point. EGSYS (Evaluation of Guidelines in Syncope Study), a syncope-specific diagnostic score, served as the diagnostic comparator. Death and major adverse cardiac events at 30 and 720 days were the prognostic end points. Major adverse cardiac events were defined as death, cardiopulmonary resuscitation, life-threatening arrhythmia, implantation of pacemaker/implantable cardioverter defibrillator, acute myocardial infarction, pulmonary embolism, stroke/transient ischemic attack, intracranial bleeding, or valvular surgery. ROSE (Risk Stratification of Syncope in the Emergency Department), OESIL (Osservatorio Epidemiologico della Sincope nel Lazio), SFSR (San Fransisco Syncope Rule), and CSRS (Canadian Syncope Risk Score) served as the prognostic comparators. RESULTS: Among 1538 patients eligible for diagnostic assessment, cardiac syncope was the adjudicated diagnosis in 234 patients (15.2%). BNP, NT-proBNP, hs-cTnT, and hs-cTnI were significantly higher in cardiac syncope versus other causes (P<0.01). The diagnostic accuracy for cardiac syncope, as quantified by the area under the curve, was 0.77 to 0.78 (95% CI, 0.74-0.81) for all 4 biomarkers, and superior to EGSYS (area under the curve, 0.68 [95%-CI 0.65-0.71], P<0.001). Combining BNP/NT-proBNP with hs-cTnT/hs-cTnI further improved diagnostic accuracy to an area under the curve of 0.81 (P<0.01). BNP, NT-proBNP, hs-cTnT, and hs-cTnI cut-offs, achieving predefined thresholds for sensitivity and specificity (95%), allowed for rule-in or rule-out of ≈30% of all patients. A total of 450 major adverse cardiac events occurred during follow-up. The prognostic accuracy of BNP, NT-proBNP, hs-cTnI, and hs-cTnT for major adverse cardiac events was moderate-to-good (area under the curve, 0.75-0.79), superior to ROSE, OESIL, and SFSR, and inferior to CSRS. CONCLUSIONS: BNP, NT-proBNP, hs-cTnT, and hs-cTnI concentrations provide useful diagnostic and prognostic information in emergency department patients with syncope. CLINICAL TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT01548352.

High-sensitivity cardiac troponin T 30 days all-come mortality in patients with acute heart failure. A Propensity Score-Matching Analysis Based on the EAHFE Registry. TROPICA4 Study.

BACKGROUND: Acute heart failure (AHF) patients with high troponin levels have a worse prognosis. High-sensitive troponin T (hs-TnT) has been used as a tool to stratify prognosis in many scales but always as a qualitative and not as a quantitative variable. OBJECTIVES: The main objective of this study was to determine the best hs-TnT cut-off for prediction of 30-day all-cause mortality. METHODS: The EAHFE registry, a prospective follow-up cohort of patients with AHF, was analysed. We performed a propensity score analysis of the optimal hs-TnT cut-off point previously determined by receiver operating characteristic (ROC) curve analysis. RESULTS: Of the 13 791 patients in the EAHFE cohort, we analysed 3190 patients in whom hs-TnT determination was available. The area under the ROC curve for 30-day all-cause mortality was 0.70 (CI95% 0.68 to 0.71; P < .001), establishing an optimal cut-off of hs-TnT of 35 ng/L. The sensitivity and specificity of this cut-off were 76.2 and 55.5%, respectively, with a negative predictive value (NPV) of 95.3%. A propensity score was made with 34 variables showing differences based on the cut-off of 35 ng/L for hs-TnT. In the analysis of the population obtained with the propensity score, patients with hs-TnT > 35 ng/L showed a greater 30-day all-cause mortality, with a HR of 2.95 (CI95% 1.83-4.75; P < .001). External validation reported similar results. CONCLUSIONS: An hs-TnT value of 35 ng/L is an adequate cut-off to evaluate the prediction of 30-day all-cause mortality with a NPV of 95.3%.

Incidence, characteristics, determinants, and prognostic impact of recurrent syncope.

AIMS: The aim of this study is to characterize recurrent syncope, including sex-specific aspects, and its impact on death and major adverse cardiovascular events (MACE). METHODS AND RESULTS: We characterized recurrent syncope in a large international multicentre study, enrolling patients ≥40 years presenting to the emergency department (ED) with a syncopal event within the last 12 h. Syncope aetiology was centrally adjudicated by two independent cardiologists using all information becoming available during syncope work-up and long-term follow-up. Overall, 1790 patients were eligible for this analysis. Incidence of recurrent syncope was 20% [95% confidence interval (CI) 18-22%] within the first 24 months. Patients with an adjudicated final diagnosis of cardiac syncope (hazard ratio (HR) 1.50, 95% CI 1.11-2.01) or syncope with an unknown aetiology even after central adjudication (HR 2.11, 95% CI 1.54-2.89) had an increased risk for syncope recurrence. Least Absolute Shrinkage and Selection Operator regression fit on all patient information available early in the ED identified >3 previous episodes of syncope as the only independent predictor for recurrent syncope (HR 2.13, 95% CI 1.64-2.75). Recurrent syncope carried an increased risk for death (HR 1.87, 95% CI 1.26-2.77) and MACE (HR 2.69, 95% CI 2.02-3.59) over 24 months of follow-up, however, with a time-dependent effect. These findings were confirmed in a sensitivity analysis excluding patients with syncope recurrence or MACE before or during ED evaluation. CONCLUSION: Recurrence rates of syncope are substantial and vary depending on syncope aetiology. Importantly, recurrent syncope carries a time-dependent increased risk for death and MACE. TRIAL REGISTRATION: BAsel Syncope EvaLuation (BASEL IX, ClinicalTrials.gov registry number NCT01548352).

External Validation of the MEESSI Acute Heart Failure Risk Score: A Cohort Study.

Background: The MEESSI-AHF (Multiple Estimation of risk based on the Emergency department Spanish Score In patients with AHF) score was developed to predict 30-day mortality in patients presenting with acute heart failure (AHF) to emergency departments (EDs) in Spain. Whether it performs well in other countries is unknown. Objective: To externally validate the MEESSI-AHF score in another country. Design: Prospective cohort study. (ClinicalTrials.gov: NCT01831115). Setting: Multicenter recruitment of dyspneic patients presenting to the ED. Participants: The external validation cohort included 1572 patients with AHF. Measurements: Calculation of the MEESSI-AHF score using an established model containing 12 independent risk factors. Results: Among 1572 patients with adjudicated AHF, 1247 had complete data that allowed calculation of the MEESSI-AHF score. Of these, 102 (8.2%) died within 30 days. The score predicted 30-day mortality with excellent discrimination (c-statistic, 0.80). Assessment of cumulative mortality showed a steep gradient in 30-day mortality over 6 predefined risk groups (0 patients in the lowest-risk group vs. 35 [28.5%] in the highest-risk group). Risk was overestimated in the high-risk groups, resulting in a Hosmer-Lemeshow P value of 0.022. However, after adjustment of the intercept, the model showed good concordance between predicted risks and observed outcomes (P = 0.23). Findings were confirmed in sensitivity analyses that used multiple imputation for missing values in the overall cohort of 1572 patients. Limitations: External validation was done using a reduced model. Findings are specific to patients with AHF who present to the ED and are clinically stable enough to provide informed consent. Performance in patients with terminal kidney failure who are receiving long-term dialysis cannot be commented on. Conclusion: External validation of the MEESSI-AHF risk score showed excellent discrimination. Recalibration may be needed when the score is introduced to new populations. Primary Funding Source: The European Union, the Swiss National Science Foundation, the Swiss Heart Foundation, the Cardiovascular Research Foundation Basel, the University of Basel, and University Hospital Basel.

Clinical Utility of Procalcitonin in the Diagnosis of Pneumonia.

BACKGROUND: The clinical utility of procalcitonin in the diagnosis and management of pneumonia remains controversial. METHODS: We assessed the clinical utility of procalcitonin in 2 prospective studies: first, a multicenter diagnostic study in patients presenting to the emergency department with acute dyspnea to directly compare the diagnostic accuracy of procalcitonin with that of interleukin 6 and C-reactive protein (CRP) in the diagnosis of pneumonia; second, a randomized management study of procalcitonin guidance in patients with acute heart failure and suspected pneumonia. Diagnostic accuracy for pneumonia as centrally adjudicated by 2 independent experts was quantified with the area under the ROC curve (AUC). RESULTS: Among 690 patients in the diagnostic study, 178 (25.8%) had an adjudicated final diagnosis of pneumonia. Procalcitonin, interleukin 6, and CRP were significantly higher in patients with pneumonia than in those without. When compared to procalcitonin (AUC = 0.75; 95% CI, 0.71-0.78), interleukin 6 (AUC = 0.80; 95% CI, 0.77-0.83) and CRP (AUC = 0.82; 95% CI, 0.79-0.85) had significantly higher diagnostic accuracy (P = 0.010 and P < 0.001, respectively). The management study was stopped early owing to the unexpectedly low AUC of procalcitonin in the diagnostic study. Among 45 randomized patients, the number of days on antibiotic therapy and the length of hospital stay were similar (both P = 0.39) in patients randomized to the procalcitonin-guided group (n = 25) and usual-care group (n = 20). CONCLUSIONS: In patients presenting with dyspnea, diagnostic accuracy of procalcitonin for pneumonia is only moderate and lower than that of interleukin 6 and CRP. The clinical utility of procalcitonin was lower than expected. SUMMARY: Pneumonia has diverse and often unspecific symptoms. As the role of biomarkers in the diagnosis of pneumonia remains controversial, it is often difficult to distinguish pneumonia from other illnesses causing shortness of breath. The current study prospectively enrolled unselected patients presenting with acute dyspnea and directly compared the diagnostic accuracy of procalcitonin, interleukin 6, and CRP for the diagnosis of pneumonia. In this setting, diagnostic accuracy of procalcitonin for pneumonia was lower as compared to interleukin 6 and CRP. The clinical utility of procalcitonin was lower than expected. CLINICALTRIALSGOV IDENTIFIER: NCT01831115.

Clinical Use of a New High-Sensitivity Cardiac Troponin I Assay in Patients with Suspected Myocardial Infarction.

BACKGROUND: We aimed to validate the clinical performance of the high-sensitivity cardiac troponin I [VITROS® Immunodiagnostic Products hs Troponin I (hs-cTnI-VITROS)] assay. METHODS: We enrolled patients presenting to the emergency department with symptoms suggestive of acute myocardial infarction (AMI). Final diagnoses were centrally adjudicated by 2 independent cardiologists considering all clinical information, including cardiac imaging: first, using serial hs-cTnT-Elecsys (primary analysis) and, second, using hs-cTnI-Architect (secondary analysis) measurements in addition to the clinically used (hs)-cTn. hs-cTnI-VITROS was measured at presentation and at 1 h in a blinded fashion. The primary objective was direct comparison of diagnostic accuracy as quantified by the area under the ROC curve (AUC) of hs-cTnI-VITROS vs hs-cTnT-Elecsys and hs-cTnI-Architect, and in a subgroup also hs-cTnI-Centaur and hs-cTnI-Access. Secondary objectives included the derivation and validation of an hs-cTnI-VITROS-0/1-h algorithm. RESULTS: AMI was the adjudicated final diagnosis in 158 of 1231 (13%) patients. At presentation, the AUC for hs-cTnI-VITROS was 0.95 (95% CI, 0.93-0.96); for hs-cTnT-Elecsys, 0.94 (95% CI, 0.92-0.95); and for hs-cTnI-Architect, 0.92 (95% CI, 0.90-0.94). AUCs for hs-cTnI-Centaur and hs-cTnI-Access were 0.95 (95% CI, 0.94-0.97). Applying the derived hs-cTnI-VITROS-0/1-h algorithm (derivation cohort n = 519) to the validation cohort (n = 520), 53% of patients were ruled out [sensitivity, 100% (95% CI, 94.1-100)] and 14% of patients were ruled in [specificity, 95.6% (95% CI, 93.4-97.2)]. Patients ruled out by the 0/1-h algorithm had a survival rate of 99.8% at 30 days. Findings were confirmed in the secondary analyses using the adjudication including serial measurements of hs-cTnI-Architect. CONCLUSIONS: The hs-cTnI-VITROS assay has at least comparable diagnostic accuracy with the currently best validated hs-cTnT and hs-cTnI assays. CLINICALTRIALSGOV IDENTIFIER: NCT00470587.

Two-Hour Algorithm for Rapid Triage of Suspected Acute Myocardial Infarction Using a High-Sensitivity Cardiac Troponin I Assay.

BACKGROUND: We aimed to derive and externally validate a 0/2-h algorithm using the high-sensitivity cardiac troponin I (hs-cTnI)-Access assay. METHODS: We enrolled patients presenting to the emergency department with symptoms suggestive of acute myocardial infarction (AMI) in 2 prospective diagnostic studies using central adjudication. Two independent cardiologists adjudicated the final diagnosis, including all available medical information including cardiac imaging. hs-cTnI-Access concentrations were measured at presentation and after 2 h in a blinded fashion. RESULTS: AMI was the adjudicated final diagnosis in 164 of 1131 (14.5%) patients in the derivation cohort. Rule-out by the hs-cTnI-Access 0/2-h algorithm was defined as 0-h hs-cTnI-Access concentration <4 ng/L in patients with an onset of chest pain >3 h (direct rule-out) or a 0-h hs-cTnI-Access concentration <5 ng/L and an absolute change within 2 h <5 ng/L in all other patients. Derived thresholds for rule-in were a 0-h hs-cTnI-Access concentration ≥50 ng/L (direct rule-in) or an absolute change within 2 h ≥20 ng/L. In the derivation cohort, these cutoffs ruled out 55% of patients with a negative predictive value (NPV) of 99.8% (95% CI, 99.3-100) and sensitivity of 99.4% (95% CI, 96.5-99.9), and ruled in 30% of patients with a positive predictive value (PPV) of 73% (95% CI, 66.1-79). In the validation cohort, AMI was the adjudicated final diagnosis in 88 of 1280 (6.9%) patients. These cutoffs ruled out 77.9% of patients with an NPV of 99.8% (95% CI, 99.3-100) and sensitivity of 97.7% (95% CI, 92.0-99.7), and ruled in 5.8% of patients with a PPV of 77% (95% CI, 65.8-86) in the validation cohort. CONCLUSIONS: Safety and efficacy of the l hs-cTnI-Access 0/2-h algorithm for triage toward rule-out or rule-in of AMI are very high. TRIAL REGISTRATION: APACE, NCT00470587; ADAPT, ACTRN1261100106994; IMPACT, ACTRN12611000206921.

High-Sensitivity Cardiac Troponin I Assay for Early Diagnosis of Acute Myocardial Infarction.

BACKGROUND: The aim of this study was to validate the clinical performance of the Beckman Access high-sensitivity cardiac troponin I (hs-cTnI) assay. METHODS: We enrolled patients presenting to the emergency department with symptoms suggestive of acute myocardial infarction (AMI). Final diagnoses were centrally adjudicated by 2 independent cardiologists with all clinical information including cardiac imaging twice: first, using serial hs-cTnT (Elecsys, primary analysis), and second, using hs-cTnI (Architect, secondary analysis) measurements in addition to the clinically used hs-cTn. hs-cTnI Access was measured at presentation and at 1 h. The primary objective was a direct comparison of diagnostic accuracy as quantified by the area under the ROC curve (AUC) of hs-cTnI Access vs the hs-cTnT Elecsys and hs-cTnI Architect assays. Secondary objectives included the derivation and validation of an hs-cTnI Access-specific 0/1-h algorithm. RESULTS: AMI was the adjudicated final diagnosis in 243 of 1579 (15.4%) patients. The AUC at presentation for hs-cTnI Access was 0.95 (95% CI, 0.94-0.96), higher than hs-cTnI Architect [0.92 (95% CI, 0.91-0.94; P < 0.001)] and comparable to hs-cTnT Elecsys [0.94 (95% CI, 0.93-0.95; P = 0.12)]. Applying the derived hs-cTnI Access 0/1-h algorithm (derivation cohort n = 686) to the validation cohort (n = 680), 60% of patients were ruled out [sensitivity, 98.9% (95% CI, 94.3-99.8)], and 15% of patients were ruled in [specificity, 95.9% (95% CI, 94.0-97.2)]. Patients ruled out by the 0/1-h algorithm had a survival rate of 100% at 30 days. Findings were confirmed in the secondary analyses by the adjudication including serial measurements of Architect hs-cTnI. CONCLUSIONS: Diagnostic accuracy and clinical utility of the Beckman hs-cTnI Access assay are very high and at least comparable to Roche hs-cTnT and Abbott hs-cTnI assays. ClinicalTrials.gov Identifier: NCT00470587.

Predicting Acute Myocardial Infarction with a Single Blood Draw.

BACKGROUND: We desired to determine cardiac troponin (cTn) concentrations necessary to achieve a positive predictive value (PPV) of ≥75% for acute myocardial infarction (AMI) to justify immediate admission of patients to a monitored unit and, in general, early coronary angiography. METHODS: In a prospective multicenter diagnostic study enrolling patients presenting to the emergency department with symptoms suggestive of AMI, final diagnoses were adjudicated by 2 independent cardiologists based on clinical information including cardiac imaging. cTn concentrations were measured using 5 different sensitive and high-sensitivity cTn (hs-cTn) assays in a blinded fashion at presentation and serially thereafter. The diagnostic end point was PPV for rule-in of AMI of initial cTn concentrations alone and in combination with early changes. RESULTS: Among 3828 patients, 616 (16%) had an AMI. At presentation, 7% to 14% of patients had cTnT/I concentrations associated with a PPV of ≥75%. Adding absolute or relative changes did not significantly further increase the PPV. PPVs increased from 46.5% (95% CI, 43.6-49.4) for hs-cTnT at presentation >14 ng/L to 78.9% (95% CI, 74.7-82.5) for >52 ng/L (P < 0.001), whereas PPVs in higher hs-cTnT strata remained largely unchanged [e.g., 82.4% (95% CI, 77.5-86.7) for >80 ng/L vs 83.9% (95% CI, 76.0-90.1) for >200 ng/L (P = 0.72)]. The addition of early changes in hs-cTnT further increased the PPV up to 60 ng/L, but not for higher concentrations. CONCLUSIONS: Serial sampling does not seem necessary for predicting AMI and concurrent decision-making in about 10% of patients, as it only marginally increases the PPV for AMI and not in a statistically or clinically significant way. CLINICALTRIALSGOV IDENTIFIER: NCT00470587.

Prevalence and determinants of exercise-induced left ventricular dysfunction in patients with coronary artery disease.

BACKGROUND: The phenomenon of exercise-induced left ventricular dysfunction (LVD) is incompletely understood. Better understanding of its prevalence and determinants might help to address the current potential oversimplification of the relation between physical activity and cardiac health in patients with coronary artery disease (CAD). METHODS: We prospectively assessed the prevalence and determinants of exercise-induced LVD in patients with stable CAD and normal LV function at rest undergoing bicycle rest/stress myocardial perfusion imaging single-photon emission computed tomography (MPI-SPECT). Exercise-induced LVD was defined as a relevant (5% or more) drop in left ventricular ejection fraction after maximal exercise. High-sensitivity cardiac troponin I/T (Hs-cTnI/T) and N-terminal probrain natriuretic peptide (NT-proBNP) concentrations were measured before exercise to quantify cardiomyocyte injury and hemodynamic cardiac stress, respectively. RESULTS: Among 317 patients, exercise-induced LVD was present in 83 (26%) patients. Exercise-induced LVD was associated with the extent of exercise-inducible myocardial ischaemia as well as transient ischaemic dilatation. Still, 43% of patients developing exercise-induced LVD did not have functionally relevant CAD. Neither baseline characteristics, nor the quantification of the extent of cardiomyocyte injury and hemodynamic cardiac stress using hs-cTnI/T and NT-proBNP concentrations, respectively, allowed predicting exercise-induced LVD. CONCLUSION: One out of four patients with stable CAD develops exercise-induced LVD after bicycle exercise test. While the extent of exercise-inducible myocardial ischaemia is a predictor, other still unrecognized mechanisms also seem to play a major role, as nearly half of all patients with exercise-induced LVD do not have functionally relevant CAD.