The Significance Of Troponin Elevation In Atrial Fibrillation

Coronary artery thromboembolism as a cause of myocardial infarction with non-obstructive coronary arteries (MINOCA)

Acute myocardial infarction (AMI) usually represents the clinical manifestation of atherothrombotic coronary artery disease (CAD) resulting from atherosclerotic plaque rupture. However, there are cases in which coronary angiography or coronary computed tomography angiography reveals patients with acute coronary syndrome with non-obstructive CAD. This clinical entity is defined as myocardial infarction with non-obstructive coronary arteries (MINOCA) and often considered as a clinical dynamic working diagnosis that needs further investigations for the establishment of a final etiologic diagnosis. The main causes of a MINOCA working diagnosis include atherosclerotic, non-atherosclerotic (vessel-related and non-vessel-related), and thromboembolic causes This literature review aimed to investigate the major thromboembolic causes in patients presenting with MINOCA regarding their etiology and pathophysiologic mechanisms, as well as diagnostic and treatment methods.

Diagnostic Utility of N-Terminal Pro-B-Type Natriuretic Peptide in Identifying Atrial Fibrillation Post-Cryptogenic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) significantly contributes to acute ischemic stroke, with undetected AF being a common culprit in cryptogenic strokes. N-terminal pro-B-type natriuretic peptide (NT-proBNP), indicative of myocardial stress, has been proposed as a biomarker for AF detection, aiding in the selection of patients for extended cardiac monitoring. However, the diagnostic accuracy of NT-proBNP remains uncertain.

METHODS

We conducted a meta-analysis to evaluate the diagnostic accuracy of NT-proBNP in detecting AF among cryptogenic stroke patients. A comprehensive literature search was conducted across PubMed, Embase, and Cochrane databases to identify relevant studies. Studies reporting NT-proBNP levels in stroke patients and data on the proportion of patients with AF above a specified cut-off were included. Meta-analyses were performed using the midas command in STATA.

RESULTS

Seven studies encompassing 2171 patients were included in the analysis, of which five studies contained cohorts with cryptogenic strokes. Among patients with cryptogenic stroke, NT-proBNP demonstrated a diagnostic accuracy of 80% (Area Under the Receiver Operating Curve 0.80 [95% CI 0.76-0.83]), with a sensitivity of 81% (95% CI 0.68-0.89) and a specificity of 68% (95% CI 0.60-0.75).

CONCLUSION

Our meta-analysis indicates that NT-proBNP exhibits a good-to-very-good diagnostic accuracy for detecting AF in patients with cryptogenic stroke. These findings suggest potential implications for utilizing NT-proBNP in guiding the selection of patients for prolonged cardiac monitoring, thereby aiding in the management of cryptogenic stroke cases.

Fibrinaloid Microclots and Atrial Fibrillation

Atrial fibrillation (AF) is a comorbidity of a variety of other chronic, inflammatory diseases for which fibrinaloid microclots are a known accompaniment (and in some cases, a cause, with a mechanistic basis). Clots are, of course, a well-known consequence of atrial fibrillation. We here ask the question whether the fibrinaloid microclots seen in plasma or serum may in fact also be a cause of (or contributor to) the development of AF. We consider known 'risk factors' for AF, and in particular, exogenous stimuli such as infection and air pollution by particulates, both of which are known to cause AF. The external accompaniments of both bacterial (lipopolysaccharide and lipoteichoic acids) and viral (SARS-CoV-2 spike protein) infections are known to stimulate fibrinaloid microclots when added in vitro, and fibrinaloid microclots, as with other amyloid proteins, can be cytotoxic, both by inducing hypoxia/reperfusion and by other means. Strokes and thromboembolisms are also common consequences of AF. Consequently, taking a systems approach, we review the considerable evidence in detail, which leads us to suggest that it is likely that microclots may well have an aetiological role in the development of AF. This has significant mechanistic and therapeutic implications.

Insights into the Novel Cardiac Biomarker in Acute Heart Failure: Mybp-C

(1) Background: Given its high cardiac specificity and its capacity to directly assess the cardiac function, cardiac myosin-binding protein (MyBP-C) is a promising biomarker in patients with acute heart failure (AHF). The aim of our study was to investigate the clinical utility of this novel marker for diagnosis and short-term prognosis in subjects with AHF. (2) Methods: We measured plasma levels of MyBP-C at admission in 49 subjects (27 patients admitted with AHF and 22 controls). (3) Results: The plasma concentration of MyBP-C was significantly higher in patients with AHF compared to controls (54.88 vs. 0.01 ng/L, p < 0.001). For 30-day prognosis, MyBP-C showed significantly greater AUC (0.972, p < 0.001) than NT-proBNP (0.849, p = 0.001) and hs-TnI (0.714, p = 0.047). In a multivariate logistic regression analysis, an elevated level of MyBP-C was the best independent predictor of 30-day mortality (OR = 1.08, p = 0.039) or combined death/recurrent 30-days rehospitalization (OR = 1.12, p = 0.014). (4) Conclusions: Our data show that circulating MyBP-C is a sensitive and cardiac-specific biomarker with potential utility for the accurate diagnosis and prognosis of AHF.

Cardiac Magnetic Resonance Imaging as a Risk Stratification Tool in COVID-19 Myocarditis

The aim of this retrospective study was to identify myocardial injury after COVID-19 inflammation and explore whether myocardial damage could be a possible cause of the persistent symptoms following COVID-19 infection in previously healthy individuals. This study included 139 patients who were enrolled between January and June 2021, with a mean age of 46.7 ± 15.2 years, of whom 68 were men and 71 were women without known cardiac or pulmonary diseases. All patients underwent clinical work-up, laboratory analysis, cardiac ultrasound, and CMR on a 1.5 T scanner using a recommended protocol for morphological and functional assessment before and after contrast media application with multi-parametric sequences. In 39% of patients, late gadolinium enhancement (LGE) was found as a sign of myocarditis. Fibrinogen was statistically significantly higher in patients with LGE than in those without LGE (4.3 ± 0.23 vs. 3.2 ± 0.14 g/L, p < 0.05, respectively), as well as D-dimer (1.8 ± 0.3 vs. 0.8 ± 0.1 mg/L FEU). Also, troponin was statistically significantly higher in patients with myocardial LGE (13.1 ± 0.4 ng/L) compared to those with normal myocardium (4.9 ± 0.3 ng/L, p < 0.001). We demonstrated chest pain, fatigue, and elevated troponin to be independent predictors for LGE. Septal LGE was shown to be a predictor for arrhythmias. The use of CMR is a potential risk stratification tool in evaluating outcomes following COVID-19 myocarditis.

The Intersection of Atrial Fibrillation and Coronary Artery Disease in Middle Eastern Patients. Analysis from the Jordan Atrial Fibrillation Study

Background

There is a scarcity of clinical studies which evaluate the association of atrial fibrillation (AF) and coronary artery disease (CAD) in the Middle East. The aim of this study was to evaluate the impact of CAD on baseline clinical profiles and one-year outcomes in a Middle Eastern cohort with AF.

Methods

Consecutive AF patients evaluated in 29 hospitals and cardiology clinics were enrolled in the Jordan AF Study (May 2019-December 2020). Clinical and echocardiographic features, use of medications and one-year outcomes in patients with AF/CAD were compared to AF/no CAD patients.

Results

Of 2020 AF patients enrolled, 216 (10.7%) had CAD. Patients with AF/CAD were more likely to be men and had significantly higher prevalence of hypertension, diabetes, dyslipidemia, heart failure and chronic kidney disease compared to the AF/no CAD patients. They also had lower mean left ventricular ejection fraction and larger left atrial size. Mean CHA2DS2 VASc and HAS-BLED scores were higher in AF/CAD patients than those with AF/no CAD (4.3 ± 1.7 vs. 3.6 ± 1.8, p < 0.0001) and (2.0 ± 1.1 vs. 1.6 ± 1.1, p < 0.0001), respectively. Oral anticoagulant agents were used in similar rates in the two groups (83.8% vs. 82.9%, p = 0.81), but more patients with AF/CAD were prescribed additional antiplatelet agents compared to patients with AF/no CAD (73.7% vs. 41.5%, p < 0.0001). At one year, AF/CAD patients, compared to AF/no CAD patients had significantly higher hospitalization rate (39.4% vs. 29.2%, p = 0.003), more acute coronary syndrome and coronary revascularization (6.9% vs. 2.4%, p = 0.004), and higher all-cause mortality (18.5% vs. 10.9%, p = 0.002).

Conclusions

In this cohort of Middle Eastern patients with AF, one in 10 patients had CAD. The coexistence of AF and CAD was associated with a worse baseline clinical profile and one-year outcomes. Clinical study registration: the study is registered on clinicaltrials.gov (unique identifier number NCT03917992).

ANMCO-SIMEU consensus document: appropriate management of atrial fibrillation in the emergency department

Atrial fibrillation (AF) accounts for 2% of the total presentations to the emergency department (ED) and represents the most frequent arrhythmic cause for hospitalization. It steadily increases the risk of thromboembolic events and is often associated with several comorbidities that negatively affect patient's quality of life and prognosis. AF has a considerable impact on healthcare resources, making the promotion of an adequate and coordinated management of this arrhythmia necessary in order to avoid clinical complications and to implement the adoption of appropriate technological and pharmacological treatment options. AF management varies across regions and hospitals and there is also heterogeneity in the use of anticoagulation and electric cardioversion, with limited use of direct oral anticoagulants. The ED represents the first access point for early management of patients with AF. The appropriate management of this arrhythmia in the acute setting has a great impact on improving patient's quality of life and outcomes as well as on rationalization of the financial resources related to the clinical course of AF. Therefore, physicians should provide a well-structured clinical and diagnostic pathway for patients with AF who are admitted to the ED. This should be based on a tight and propositional collaboration among several specialists, i.e. the ED physician, cardiologist, internal medicine physician, anesthesiologist. The aim of this ANMCO-SIMEU consensus document is to provide shared recommendations for promoting an integrated, accurate, and up-to-date management of patients with AF admitted to the ED or Cardiology Department, in order to make it homogeneous across the national territory.

Coronary artery disease among patients admitted with atrial fibrillation and chest pain

INTRODUCTION

Patients who present to the emergency department with chest pain during an episode of atrial fibrillation (AF) impose a clinical challenge regarding the source of pain - being coronary artery disease (CAD) or AF in origin. The aim of this study was to identify clinical, imaging or laboratory markers which can predict significant CAD among patients with an AF episode and chest pain.

METHODS

We included 57 consecutive patients admitted to our hospital with AF and chest pain. All patients underwent coronary evaluation. Significant CAD was defined as >50% stenosis in a major coronary artery by coronary angiography or cardiac CT. We compared CAD and non-CAD groups and analyzed risk factorsby regression analysis.

RESULTS

Twenty-four patients (42%) were diagnosed with- and 33 patients (58%) without obstructive CAD. In a multivariate analysis of regional wall motion abnormality (RWMA), elevated troponin and hypertension were found to be predictors for CAD [odds ratio (OR), 22.4 (confidence interval (CI), 1.8-272.4; P  = 0.02); OR, 5.6 (CI, 1-31.0; P  = 0.05) and OR, 21.4 (CI, 1.6-284.6; P  = 0.02), respectively]. There were no significant differences regarding the rate of typical chest pain at presentation in the CAD vs. the non-CAD group [13 (54%) vs. 20 (60%), P  = 0.374], or in ECG ST-changes [12 (50%) vs.9 (27%), respectively; P  = 0.08].

CONCLUSION

In patients who present acutely with chest pain and AF, troponin elevation and RWMA appear to be highly predictive of obstructive CAD, whereas clinical symptoms and ECG changes are not predictive. These findings may be helpful for guiding the management of patients admitted with AF and chest pain.

Cytotoxic CD8+ T Cells Are Involved in the Thrombo-Inflammatory Response during First-Diagnosed Atrial Fibrillation

BACKGROUND

Atrial myopathy and atrial fibrillation (AF) accompany thrombo-inflammation. This facilitates disease progression and promotes major adverse cardiovascular events (MACEs). Thrombin receptor (protease-activated receptor 1, PAR1) signalling is central in mediating thrombo-inflammation. We hypothesised that PAR1 signalling links coagulation and inflammation through cytotoxic CD8⁺ T lymphocytes in patients presenting with first-diagnosed AF (FDAF).

METHODS

A total of 210 patients were studied. We included data and blood samples from patients presenting with FDAF (n = 160), cardiac tissue from patients with paroxysmal AF (n = 32) and 20 controls.

RESULTS

During early AF, a pro-inflammatory and cytotoxic subset of T lymphocytes (CD8⁺) circulated more frequently when compared to patients with chronic cardiovascular disease but without AF, accompanied by elevated plasma levels of CD8⁺ effector molecules, which corresponded to biomarkers of adverse cardiac remodelling and atrial dysfunction. Activation of tissue factor (TF) and PAR1 was associated with pro-inflammatory and cytotoxic effector functions. PAR1-related CD8⁺ cell activation was more frequent in FDAF patients that experienced a MACE.

CONCLUSIONS

In patients with FDAF, the TF-factor Xa-factor IIa-axis contributes to thrombo-inflammation via PAR1 in CD8⁺ T cells. Intervening in this cascade might be a promising synergistic approach to reducing disease progression and the vascular complications of AF.

Chest pain workup in the presence of atrial fibrillation: impacts on troponin testing, myocardial infarction diagnoses, and long-term prognosis

AIMS

Patients presenting to the emergency department (ED) with chest pain require evaluation for acute coronary syndrome (ACS). Atrial fibrillation (AF) can lead to troponin (cTn) elevation in the absence of ACS. There is limited evidence informing the impact of AF on the diagnostic performance of cTn testing for the diagnosis of Type 1 myocardial infarction (T1MI), or the association between AF and long-term outcomes in this context.

METHODS AND RESULTS

This study used the IMPACT and ADAPT study databases to compile a combined cohort of 3496 adults presenting to ED with chest pain between 2007 and 2014, with early cTn testing during ED workup. The mean age was 56.6 years, and 40.2% were female. Outcomes included adjudicated diagnoses for the index admission and mortality to 1-year after presentation. The specificity of initial cTn testing for T1MI diagnosis was lower for patients in AF compared with those not in AF (79.2% vs. 95.4%, P < 0.001), largely due to a relative increase in Type 2 myocardial infarction diagnoses. Sensitivity for T1MI did not differ between patients with or without AF (88.5% vs. 91.5%, P = 0.485). AF was associated with increased 1-year mortality (10.4% vs. 2.3%, P < 0.001), although this was not significant on multivariable analysis.

CONCLUSION

The specificity of serial cTn testing for the diagnosis of T1MI in patients presenting to ED with chest pain is reduced in the presence of AF. Further studies are needed to establish whether optimised cTn thresholds for patients with AF can improve workup and outcomes.

A Newly Defined CHA2DS2-VA Score for Predicting Obstructive Coronary Artery Disease in Patients with Atrial Fibrillation-A Cross-Sectional Study of Older Persons Referred for Elective Coronary Angiography

Purpose: Atrial fibrillation (AF) can be a valuable indicator of non-obstructive coronary artery disease (CAD) among older patients indicated for elective coronary angiography (CAG). Appropriate stratification of AF patients is crucial for avoiding unnecessary complications. The objective of this study was to identify independent predictors that can allow diagnosing obstructive CAD in AF patients over 65 years who were indicated to undergo elective CAG. Patients and methods: This cross-sectional study included 452 (23.9%) AF patients over 65 years old who were directed to the Department of Invasive Cardiology at the Medical University of Bialystok for elective CAG during 2014−2016. The participants had CAD and were receiving optimal therapy (median age: 73 years, interquartile range: 69−77 years; 54.6% men). The prevalence and health correlates of obstructive CAD were determined, and a multivariate logistic regression model was generated with predictors (p < 0.1). Predictive performance was analyzed using a receiver-operating characteristic (ROC) curve analysis. Results: Stenosis (affecting ≥ 50% of the diameter of the left coronary artery stem or ≥70% of that of the other important epicardial vessels) was significant in 184 (40.7%) cases. Multivariate regression analysis revealed that only the male sex (odds ratio [OR]: 1.80, 95% confidence interval [CI]: 1.14−2.84, p = 0.01) and the newly created CHA2DS2-VA score (OR: 3.96, 95% CI: 2.96−5.31, p < 0.001) significantly increased the chance of obstructive CAD, while controlling for chronic kidney disease and anemia. The ROC curve analysis indicated that the CHA2DS2-VA scale may be a useful screening tool for the diagnosis of obstructive CAD (area under the ROC curve: 0.79, 95% CI: 0.75−0.84, p < 0.001), with ≥4 being the optimal cutoff value. Conclusions: Our study has proven that several older AF patients who are advised to undergo elective CAG have nonobstructive CAD. The CHA2DS2-VA score can contribute to improving the selection of patients for invasive diagnosis of CAD, but further investigation is required.

Cardiac troponins and adverse outcomes in European patients with atrial fibrillation: A report from the ESC-EHRA EORP atrial fibrillation general long-term registry

BACKGROUND

Cardiac troponins (cTn) have been reported to be predictors for adverse outcomes in atrial fibrillation (AF), patients, but their actual use is still unclear.

AIM

To assess the factors associated with cTn testing in routine practice and evaluate the association with outcomes.

METHODS

Patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry were stratified into 3 groups according to cTn levels as (i) cTn not tested, (ii) cTn in range (≤99th percentile), (iii) cTn elevated (>99th percentile). The composite outcome of any thromboembolism /any acute coronary syndrome/cardiovascular (CV) death, defined as Major Adverse Cardiovascular Events (MACE) and all-cause death were the main endpoints.

RESULTS

Among 10 445 AF patients (median age 71 years, 40.3% females) cTn were tested in 2834 (27.1%). cTn was elevated in 904/2834 (31.9%) and in-range in 1930/2834 (68.1%) patients. Female sex, in-hospital enrollment, first-detected AF, CV risk factors, history of coronary artery disease, and atypical AF symptoms were independently associated with cTn testing. Elevated cTn were independently associated with a higher risk for MACE (Model 1, hazard ratio [HR] 1.74, 95% confidence interval [CI] 1.40-2.16, Model 2, HR 1.62, 95% CI 1.28-2.05; Model 3 HR 1.76, 95% CI 1.37-2.26) and all-cause death (Model 1, HR 1.45, 95% CI 1.21-1.74; Model 2, HR 1.36, 95% CI 1.12-1.66; Model 3, HR 1.38, 95% CI 1.12-1.71).

CONCLUSIONS

Elevated cTn levels were associated with an increased risk of all-cause mortality and adverse CV events. Clinical factors that might enhance the need to rule out CAD were associated with cTn testing.

Atrial fibrillation is a predictor of nonobstructive coronary artery disease in elective angiography in old age: a cross-sectional study in Poland and Russia

BACKGROUND

Significant changes in the coronary vessels are not confirmed in a large proportion of patients undergoing cardiac catheterization.

AIMS

The present study aimed to determine correlates and independent predictors of nonobstructive coronary artery disease (CAD) in older adults referred for elective coronary angiography.

METHODS

A cross-sectional study was conducted involving 2,214 patients referred to two medical centers (in Poland and Russia) between 2014 and 2016 for elective coronary angiography due to exacerbated angina, despite undergoing optimal therapy for CAD. The median age was 72 years (IQR: 68-76), and 49.5% patients were women.

RESULTS

Significant stenosis (defined as stenosis of 50% or more of the diameter of the left main coronary artery stem or stenosis of 70% or more of the diameter of the remaining major epicardial vessels) was diagnosed only in 1135 (51.3%) patients. Female sex (odds ratio [OR], 3.01; 95% confidence interval [CI], 2.44-3.72; p < 0.001) and atrial fibrillation (OR, 1.87; 95% CI 1.45-2.40; p < 0.001) were the main independent predictors of nonobstructive CAD. Significantly lower ORs were observed for diabetes (OR, 0.75; 95% CI 0.59-0.95; p = 0.02), chronic kidney disease (OR, 0.76; 95% CI 0.61-0.96; p = 0.02), and anemia (OR, 0.69; 95% CI 0.50-0.95; p = 0.02) after controlling for age, chronic heart failure, BMI, and study center.

DISCUSSION AND CONCLUSIONS

The results confirmed that nonobstructive CAD occurs in a high percentage of older patients referred for elective coronary angiography. This suggests the need to improve patient stratification for invasive diagnosis of CAD, especially for older women and patients with atrial fibrillation. Trial registration number and date of registration: NCT04537507, September 3, 2020.

Minor troponin T elevation and mortality in patients with atrial fibrillation presenting to the emergency department

BACKGROUND

There are limited data on the association of minor troponin elevation in unselected patients with atrial fibrillation (AF) presenting to the emergency department (ED) with adverse events. In this study, we sought to assess the early and mid-term mortality of these patients.

METHODS

In this observational study, 2911 patients with AF were admitted to the ED. They were divided into 3 groups based on peak high-sensitivity troponin (TnT) levels: normal (<15 ng/L), 15-50 ng/L and 51-100 ng/L. The primary outcomes of this study were all-cause mortality at 30 days and 1 year.

RESULTS

All-cause mortality was 6.7% (n = 196) at 30 days and 22.2% (n = 646) at 1 year. Mortality rate increased along with increasing levels of TnT irrespective of baseline covariates, primary discharge diagnosis and type of AF. A significant association between TnT levels and all-cause mortality was observed. The adjusted hazard ratio (HR) at 30 days was 6.02 (95% CI 2.62-13.83) for TnT 15-50 ng/L and 11.28 (95% CI 4.87-26.12) for TnT 51-100 ng/L (P<.001 for both) compared to TnT <15 ng/L. At 1 year, the adjusted HRs were 3.08 (95% CI 2.15-4.40) and 5.07 (95% CI 3.49-7.35), respectively (P < .001). When patients with TnT <15 ng/L were divided into two groups at the median value, TnT elevation of 10 to 14 ng/L was also associated with increased 1-year mortality (HR 2.51; 95% CI 1.09-5.74; P = .03).

CONCLUSIONS

Among patients with AF admitted to the ED, increased TnT levels were associated with increased early and mid-term all-cause mortality irrespective of baseline covariates and type of AF.

Recent-onset atrial fibrillation: a study exploring the elements of Virchow's triad after cardioversion

Purpose

Atrial fibrillation (AF) imposes an inherent risk for stroke and silent cerebral emboli, partly related to left atrial (LA) remodeling and activation of inflammatory and coagulation systems. The aim was to explore the effects of cardioversion (CV) and short-lasting AF on left atrial hemodynamics, inflammatory, coagulative and cardiac biomarkers, and the association between LA functional recovery and the presence of a prior history of AF.

Methods

Patients referred for CV within 48 h after AF onset were prospectively included. Echocardiography and blood sampling were performed immediately prior, 1–3 h after, and at 7–10 days after CV. The presence of chronic white matter hyperintensities (WMH) on magnetic resonance imaging was related to biomarker levels.

Results

Forty-three patients (84% males), aged 55±9.6 years, with median CHA₂DS₂-VASc score 1 (IQR 0–1) were included. The LA emptying fraction (LAEF), LA peak longitudinal strain during reservoir, conduit, and contractile phases improved significantly after CV. Only LAEF normalized within 10 days. Interleukin-6, high-sensitivity cardiac-troponin-T (hs-cTNT), N-terminal-pro-brain-natriuretic peptide, prothrombin-fragment 1+2 (PTf1+2), and fibrinogen decreased significantly after CV. There was a trend towards higher C-reactive protein, hs-cTNT, and PTf1+2 levels in patients with WMH (n=21) compared to those without (n=22). At 7–10 days, the LAEF was significantly lower in patients with a prior history of AF versus those without.

Conclusion

Although LA stunning resolved within 10 days, LAEF remained significantly lower in patients with a prior history of AF versus those without. Inflammatory and coagulative biomarkers were higher before CV, but subsided after 7–10 days, which altogether might suggest an enhanced thrombogenicity, even in these low-risk patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10840-021-01078-9.

Immunoinflammatory, Thrombohaemostatic, and Cardiovascular Mechanisms in COVID-19

The global coronavirus disease 2019 (COVID-19) pandemic has deranged the recent history of humankind, afflicting more than 27 million individuals to date. While the majority of COVID-19 patients recuperate, a considerable number of patients develop severe complications. Bilateral pneumonia constitutes the hallmark of severe COVID-19 disease but an involvement of other organ systems, namely the cardiovascular system, kidneys, liver, and central nervous system, occurs in at least half of the fatal COVID-19 cases. Besides respiratory failure requiring ventilation, patients with severe COVID-19 often display manifestations of systemic inflammation and thrombosis as well as diffuse microvascular injury observed postmortem. In this review, we survey the mechanisms that may explain how viral entry and activation of endothelial cells by severe acute respiratory syndrome coronavirus 2 can give rise to a series of events including systemic inflammation, thrombosis, and microvascular dysfunction. This pathophysiological scenario may be particularly harmful in patients with overt cardiovascular disease and may drive the fatal aspects of COVID-19. We further shed light on the role of the renin-angiotensin aldosterone system and its inhibitors in the context of COVID-19 and discuss the potential impact of antiviral and anti-inflammatory treatment options. Acknowledging the comorbidities and potential organ injuries throughout the course of severe COVID-19 is crucial in the clinical management of patients affecting treatment approaches and recovery rate.

Prognostic Value of Troponin in Patients with Atrial Fibrillation Admitted to an Emergency Department: Review and Meta-Analysis

Introduction

Elevated levels of cardiac troponin (cTn) indicate underlying heart disease and is known to predict adverse events in multiple conditions. Its role in atrial fibrillation (AF) in the acute setting is still not conclusive. We aimed to assess the prognostic value of c-Tn in patients with AF admitted to an emergency department (ED).

Methods

Systematic searches were conducted using PubMed and the Cochrane Library and the International Clinical Trials Registry Platform to identify studies from year 2009 to October 2019 reporting on the prognostic value of cTn on all-cause mortality or major adverse cardiac events (MACE) in adult patients with AF in the ED. We pooled hazard ratio (HR) and 95% confidence interval (CI) using fixed and random effects models according the heterogeneity. We planned to conduct a sensitivity and subgroup analyses.

Results

Five studies involving 5750 patients were identified. The mean follow-up ranged from 12 to 35 months. An increase in mortality was observed in the elevated cTn group compared to the controls, HR=2.7 (95% CI 1.55-4.72), P for effect<0.001, I2=80%). For MACE, the pooled HR was 2.17 (95%CI 1.60-2.94), P for effect<0.001, I2=0%). In the subgroup analysis we found no significant difference in type of troponin used and study design.

Conclusions

The elevation of cardiac troponin was significantly associated with higher mortality and major adverse cardiac events in patients with AF admitted to an ED. In this setting the use of c-Tn could provide prognostic information.

Predictors of time to conversion of new-onset atrial fibrillation to sinus rhythm with amiodarone therapy

BACKGROUND

New-onset atrial fibrillation (AF) is a frequent cause of presentation to the emergency department (ED). Epicardial fat thickness (EFT) is associated with the presence and recurrence of AF. However, no study has investigated the predictors of the time to conversion of AF to sinus rhythm with amiodarone therapy. The aim of this study was to investigate predictors of time to conversion of AF to sinus rhythm in patients with new-onset AF.

METHODS

A total of 122 patients admitted to the ED with symptoms of hemodynamically stable new-onset AF (lasting <48 hours) were registered consecutively. These patients received intravenous amiodarone. EFT was measured using 2D echocardiography in parasternal long-axis views.

RESULTS

A significant positive correlation was determined between EFT and conversion time (rho = 0.267, P = .017) in all patients. The median time for conversion from the start of amiodarone infusion was 410 min (150-830 minutes). Based on the median conversion time, patients were classified as early conversion (time < 410 minutes; n = 41) and late conversion (time > 410 minutes; n = 40). Multivariate logistic regression analysis demonstrated that EFT (P = .033, odds ratio [OR]: 1.68, 95% confidence interval [CI]: 1.6-2.7), higher troponin I level > 0.04 (P = .034, OR: 5.3, 95% CI: 1.1-24.8), and lower age (P = .003, OR: 0.8, 95% CI: 0.8-0.9) were significantly associated with longer conversion time.

CONCLUSIONS

We determined that EFT and high troponin level affected the time to conversion to sinus rhythm in patients with new-onset AF.

Characterization of troponin I levels post synchronized direct current cardioversion of atrial arrhythmias in patients with and without cardiomyopathy

BACKGROUND

Cardiac-specific markers of myocardial injury, such as troponin I (TnI), are often elevated following procedures that stimulate the myocardium. This study aimed to determine the effect of synchronized direct current (DC) cardioversion of atrial arrhythmias on myocardial injury 6-h post-procedure, as measured by cardiac TnI in patients with and without cardiomyopathy.

METHODS

Seventy-three individuals (59 M:14 F) participated in this study. Inclusion criteria were subjects 18 and older undergoing DC cardioversion for an atrial arrhythmia, including elective and non-elective admissions. Exclusion criteria included MI or CABG within the past month, cardioversion for a ventricular arrhythmia, or recent shock by implantable internal cardioverter defibrillator. Patients underwent standard DC cardioversion procedure with blood work (TnI and CRP) prior to and 6-h post-cardioversion. Primary outcome was change in TnI. Secondary outcomes included changes in CRP, correlation of TnI with cumulative energy and LVM, and a sub-group analysis in patients with cardiomyopathy.

RESULTS

There was no significant change in TnI following cardioversion (20.4 ± 7.9 vs. 17.5 ± 6.5 ng/L, F(1,72) = 2.651, p = 0.108). When stratified by cardiomyopathy status, there was a statistically significant reduction in TnI following cardioversion in the non-cardiomyopathy group (6.7 ± 3.7 ng/L vs. 6.2 ± 3.2 ng/L, F(1,58) = 6.481, p = 0.014) and a clinically significant reduction in the cardiomyopathy group (74.4 ± 136.7 ng/L vs. 54.6 ± 104.3 ng/L, F(1,13) = 3.676, p = 0.07). There was no significant relationship between change in TnI and cumulative energy or LVM (r = 0.137, p = 0.306 and r = 0.125, p = 0.412 respectively).

CONCLUSIONS

Synchronized DC cardioversion of an atrial arrhythmia did not cause myocardial injury 6-h post-cardioversion. Sub-group analysis suggests that cardioversion of patients with cardiomyopathy may result in normalization of TnI levels.

Prognostic significance of troponin level in 3121 patients presenting with atrial fibrillation (The NIHR Health Informatics Collaborative TROP-AF study)

Background Patients presenting with atrial fibrillation (AF) often undergo a blood test to measure troponin, but interpretation of the result is impeded by uncertainty about its clinical importance. We investigated the relationship between troponin level, coronary angiography, and all-cause mortality in real-world patients presenting with AF. Methods and Results We used National Institute of Health Research Health Informatics Collaborative data to identify patients admitted between 2010 and 2017 at 5 tertiary centers in the United Kingdom with a primary diagnosis of AF. Peak troponin results were scaled as multiples of the upper limit of normal. A total of 3121 patients were included in the analysis. Over a median follow-up of 1462 (interquartile range, 929-1975) days, there were 586 deaths (18.8%). The adjusted hazard ratio for mortality associated with a positive troponin (value above upper limit of normal) was 1.20 (95% CI, 1.01-1.43; P<0.05). Higher troponin levels were associated with higher risk of mortality, reaching a maximum hazard ratio of 2.6 (95% CI, 1.9-3.4) at ≈250 multiples of the upper limit of normal. There was an exponential relationship between higher troponin levels and increased odds of coronary angiography. The mortality risk was 36% lower in patients undergoing coronary angiography than in those who did not (adjusted hazard ratio, 0.61; 95% CI, 0.42-0.89; P=0.01). Conclusions Increased troponin was associated with increased risk of mortality in patients presenting with AF. The lower hazard ratio in patients undergoing invasive management raises the possibility that the clinical importance of troponin release in AF may be mediated by coronary artery disease, which may be responsive to revascularization.

Association of Serum Troponin Obtained During Stroke Codes with Cardioembolic Strokes

BACKGROUND

Troponin is a marker of cardiac ischemia and is elevated in about 30% of stroke patients. We investigated if the elevation of troponin during an acute stroke code is associated with a cardioembolic source.

METHODS

We performed a retrospective chart review of patients evaluated for acute strokes from July 2014 to March 2018. Patients included in the study were all given intravenous alteplase, had blood drawn for troponins during the acute stroke code and had confirmation of a new stroke on neuroimaging during hospitalization. Patients who were on dialysis or had a glomerular filtration rate of less than or equal to 40 ml/minutes on initial laboratory evaluation were excluded. Stroke etiology was classified into noncardioembolic (NCE) and cardioembolic (CE), according to Trial of Org 10172 in Acute Stroke Treatment criteria. The NCE group was compared with the CE group with respect to troponin levels. Troponin was considered as a dichotomous categorical variable, with a cut-off point at greater than or equal to.05 ng/ml.

RESULTS

144 patients met the inclusion criteria. In our cohort, 40.74% of patients in the CE group had troponin levels of greater than or equal to .05 ng/mL compared to 12.22% in NCE group. A troponin level of greater than or equal to.05 ng/ml obtained during a stroke code showed a significant difference between cardioembolic and noncardioembolic strokes (OR, 4.94; 95% CI, 2.15-11.35; P < .001), with high specificity (87.78%) but low sensitivity (40.74%) to exclude noncardioembolic stroke.

CONCLUSIONS

A troponin level of greater than or equal to .05 ng/ml obtained during a stroke code showed a significant difference between CE and NCE strokes. This finding may have implications for clinical workup, and patients with admission troponin levels of greater than or equal to .05 ng/mL may need further clinical investigations to look for a cardioembolic source. A troponin level of greater than or equal to .05 ng/ml may prompt a more thorough search for a cardioembolic source in cases in which such a source is not identified on initial evaluation.

Etiology of Minor Troponin Elevations in Patients with Atrial Fibrillation at Emergency Department-Tropo-AF Study

Patients with atrial fibrillation (AF) presenting to the emergency department (ED) often have elevated cardiac troponin T (TnT) levels without evidence of type 1 myocardial infarction. We sought to explore the causes and significance of minor TnT elevations in patients with AF at the ED. All patients with AF admitted to the ED of Turku University Hospital between 1 March, 2013 and 11 April, 2016, and at least two TnT measurements, were screened. Overall, 2911 patients with a maximum TnT of 100 ng/L during hospitalization were analyzed. TnT was between 15 and 100 ng/L in 2116 patients. The most common primary discharge diagnoses in this group were AF (18.1%), infection (18.3%), ischemic stroke/transient ischemic attack (10.7%), and heart failure (5.0%). Acute coronary syndrome (ACS) was equally uncommon both in patients with normal TnT and elevated TnT (4.4% vs. 4.5%). Age ≥75 years, low estimated glomerular filtration rate (eGFR), high C-reactive protein (CRP), and hemoglobin <10.0 g/dL, were the most important predictors of elevated TnT. Importantly, TnT elevation was a very frequent (>93%) finding in elderly (≥75 years) AF patients with either low eGFR or high CRP. In conclusion, minor TnT elevations carry limited diagnostic value in elderly AF patients with comorbidities.

Biomarkers in the risk assessment for stroke and dementia in atrial fibrillation

PURPOSE OF REVIEW

Atrial fibrillation is one of the most common clinically encountered arrhythmias exhibiting a strong association with a spectrum of cerebral injuries from the occurrence of clinical stroke, subclinical stroke, dementia, and cognitive decline. Dynamic noninvasive specific and sensitive diagnostic tests may allow a personalized approach to the atrial fibrillation patient's treatment based upon quantitative parameters, aiming to prevent or delay stroke, dementia, progressive cognitive decline, or to assess responses to these therapies. This review will explore molecular markers that have been shown to have an association with atrial fibrillation, and have a potential to be predictive for the risk for stroke, cognitive dysfunction, and dementia in these patients.

RECENT FINDINGS

Circulating biomarkers of vascular disease, fibrosis, thrombosis, and inflammation are associated with risk of stroke in patients with atrial fibrillation. These biomarkers are additive to the predictive utility of the CHADS2 and CHA2DS2-VASc scores, and in some cases allow for additional risk prognostication of the broad categories allocated by CHADS2 and CHA2DS2-VASc scores of low, medium, and high.

SUMMARY

Across the spectrum of cerebral injuries in patients with atrial fibrillation, biomarkers hold the promise of personalized risk stratification and management to minimize risks of disease.

Evaluation of Molecularly Imprinted Polymers for Point-of-Care Testing for Cardiovascular Disease

Molecular imprinting is a rapidly growing area of interest involving the synthesis of artificial recognition elements that enable the separation of analyte from a sample matrix and its determination. Traditionally, this approach can be successfully applied to small analyte (<1.5 kDa) separation/ extraction, but, more recently it is finding utility in biomimetic sensors. These sensors consist of a recognition element and a transducer similar to their biosensor counterparts, however, the fundamental distinction is that biomimetic sensors employ an artificial recognition element. Molecularly imprinted polymers (MIPs) employed as the recognition elements in biomimetic sensors contain binding sites complementary in shape and functionality to their target analyte. Despite the growing interest in molecularly imprinting techniques, the commercial adoption of this technology is yet to be widely realised for blood sample analysis. This review aims to assess the applicability of this technology for the point-of-care testing (POCT) of cardiovascular disease-related biomarkers. More specifically, molecular imprinting is critically evaluated with respect to the detection of cardiac biomarkers indicative of acute coronary syndrome (ACS), such as the cardiac troponins (cTns). The challenges associated with the synthesis of MIPs for protein detection are outlined, in addition to enhancement techniques that ultimately improve the analytical performance of biomimetic sensors. The mechanism of detection employed to convert the analyte concentration into a measurable signal in biomimetic sensors will be discussed. Furthermore, the analytical performance of these sensors will be compared with biosensors and their potential implementation within clinical settings will be considered. In addition, the most suitable application of these sensors for cardiovascular assessment will be presented.

Elevation of high-sensitivity cardiac troponin T at admission is associated with increased 3-month mortality in acute ischemic stroke patients treated with thrombolysis

Background

Elevated levels of cardiac troponin T (cTnT) have been associated with unfavorable outcomes in cardiac patients. However, no studies, to date, have discussed the prognostic value of high‐sensitivity cTnT (hs‐cTnT) in thrombolyzed patients with acute ischemic stroke (AIS).

Hypothesis

We hypothesized that elevated levels of hs‐cTnT would be associated with poorer clinical outcomes in AIS patients treated with intravenous tissue‐type plasminogen activator (IV tPA).

Methods

From January 2017 to February 2018, a total of 241 AIS patients treated with IV tPA within 4.5 hours of onset were recruited. On admission, patients were stratified into either normal or elevated hs‐cTnT groups according to a cutoff value of 14 ng/L. Multivariable logistic regression analyses were conducted to identify determinants of hs‐cTnT elevation and to detect whether elevated hs‐cTnT was associated with disability and/or mortality.

Results

In multivariable regression analysis, older age (P < .001) and stroke etiology (P = .024) were significantly associated with elevated hs‐cTnT levels. After adjusting for demographic and clinical characteristics, hs‐cTnT elevation was still significantly associated with 14‐day major disability (modified Rankin Scale (mRS) 3‐5, model 1, P = .019, odds ratio [OR] 2.677; model 2, P = .015, OR 2.834), 14‐day composite unfavorable outcome (mRS 3‐6, model 1, P = .005, OR 3.525; model 2, P = .003, OR 3.976), 30‐day mortality (P = .049, OR 4.545) and 90‐day mortality (P = .049, OR 3.835).

Conclusions

Elevation of hs‐cTnT at admission is associated with an increased risk of 90‐day mortality in AIS patients treated with IV tPA.