Elevated troponin levels as a predictor of mortality in patients with acute stroke: a systematic review and meta-analysis

Background and Aim

The prognostic potential of cardiac troponin (cTn) in acute stroke patients has been a subject of ongoing debate. Our objective was to provide a comprehensive evidence for predicting mortality in acute stroke patients by using the elevated troponin levels.

Methods

We conducted an extensive literature search, including PubMed, EMbase, and Trip Databases, covering studies published up to September 30, 2023. We computed risk ratios (RR) with 95% confidence intervals (CIs), performed sensitivity analysis, and conducted trial sequential analysis (TSA).

Results

In total, 53 studies were analyzed, with 37 focusing on acute ischemic stroke (AIS), 11 on subarachnoid hemorrhage (SAH), and 7 on Intracerebral hemorrhage (ICH). Elevated cTn levels were significantly showed a higher predictive risk for In-hospital mortality in both AIS (RR=3.80, 95% CI; 2.82 to 5.12) as well as SAH (RR=2.23, 95% CI; 1.64 to 3.02). However, no significant predictive risk between elevated cTn levels and in-hospital mortality for ICH patients (RR=1.13, 95% CI: 0.46 to 2.79). A similar pattern was observed for elevated cTn levels, indicating an increased risk of last follow-up mortality for AIS (RR=2.41, 95% CI: 1.98 to 2.93) and SAH (RR=3.08, 95% CI: 2.25 to 4.21).

Conclusion

Elevated troponin levels can serve as a promising predictive marker for both in-hospital and last follow-up mortality in AIS and SAH patients but not in ICH patients. Further prospective studies are needed to validate our findings along with exploring the preventive management of mortality in acute stroke settings.

Frequency, associated variables, and outcomes of acute myocardial injury according to the fourth Universal Definition of Myocardial Infarction in patients with acute ischemic stroke

BACKGROUND

Myocardial injury as indicated by elevation of cardiac troponin levels is common after acute ischemic stroke (AIS) and linked to poor outcomes. Previous studies rarely reported on serial hs-cTn measurements to distinguish whether myocardial injury is acute or chronic. Thus, little is known about frequency, associated variables, and outcome of acute myocardial injury in AIS.

METHODS AND PATIENTS

In this single-centered observational cohort study, from 01/2019 to 12/2020, consecutive patients with neuroimaging-confirmed AIS <48 h after symptom onset, and serial troponin measurements within the first 2 days after admission (Roche Elecsys®, hs-cardiac troponin T) were prospectively registered. Acute myocardial injury was defined according to the fourth Universal Definition of Myocardial Infarction (troponin above the upper reference limit and rise/fall>20%). Outcomes of interest were in-hospital mortality and unfavorable functional status at discharge (modified Rankin Scale >1).

RESULTS

Out of 1067 analyzed patients, 25.3% had acute myocardial injury, 40.4% had chronic myocardial injury and 34.3% had no myocardial injury. Older age, higher stroke severity, thrombolytic treatment, and impaired kidney function were independently associated with acute myocardial injury. In-hospital mortality was higher in patients with acute myocardial injury than in those without (13% vs 3%, adjusted OR, 2.9% [95% CI, 1.6-5.5]). Compared with no myocardial injury, both acute and chronic myocardial injury were associated with unfavorable functional status at discharge (adjusted OR, 1.6 [95% CI, 1.1-2.5] and OR, 1.7 [95% CI, 1.2-2.4], respectively).

CONCLUSIONS

A quarter of patients with AIS have evidence of acute myocardial injury according to the fourth Universal Definition of Myocardial Infarction. The strong association with in-hospital mortality highlights the need for clinical awareness and future studies on underlying mechanisms.

Rapid and low-cost, and disposable electrical sensor using an extended gate field-effect transistor for cardiac troponin I detection

Field effect transistor (FET) biosensor is based on metal oxide field effect transistor that is gated by changes in the surface charges induced the reaction of biomolecules. In most cases of FET biosensor, FET biosensor is not being reused after the reaction; therefore, it is an important concept of investigate the biosensor with simplicity, cheap and reusability. However, the conventional cardiac troponin I (cTnI) sensing technique is inadequate owing to its low sensitivity and high operational time and cost. In this study, we developed a rapid and low-cost, and disposable electrical sensor using an extended gate field-effect transistor (EGFET) to detect cTnI, as a key biomarker for myocardiac infarction. We first investigated pH sensing characteristics according to the pH level, which provided a logarithmically linear sensitivity in the pH sensing buffer solution of approximately 57.9 mV/pH. Subsequently, we prepared a cTnI sample and monitored the reaction between cTnI and cTnI antibodies through the changes in the drain current and transfer curves. Our results showed that the EGFET biosensor could successfully detect the cTnI levels as well as the pH with low-cost and rapid detection.

Acute Heart Failure After Reperfused Ischemic Stroke: Association With Systemic and Cardiac Inflammatory Responses

Patients with acute ischemic stroke (AIS) present an increased incidence of systemic inflammatory response syndrome and release of Troponin T coinciding with cardiac dysfunction. The nature of the cardiocirculatory alterations remains obscure as models to investigate systemic interferences of the brain-heart-axis following AIS are sparse. Thus, this study aims to investigate acute cardiocirculatory dysfunction and myocardial injury in mice after reperfused AIS. Ischemic stroke was induced in mice by transient right-sided middle cerebral artery occlusion (tMCAO). Cardiac effects were investigated by electrocardiograms, 3D-echocardiography, magnetic resonance imaging (MRI), invasive conductance catheter measurements, histology, flow-cytometry, and determination of high-sensitive Troponin T (hsTnT). Systemic hemodynamics were recorded and catecholamines and inflammatory markers in circulating blood and myocardial tissue were determined by immuno-assay and flow-cytometry. Twenty-four hours following tMCAO hsTnT was elevated 4-fold compared to controls and predicted long-term survival. In parallel, systolic left ventricular dysfunction occurred with impaired global longitudinal strain, lower blood pressure, reduced stroke volume, and severe bradycardia leading to reduced cardiac output. This was accompanied by a systemic inflammatory response characterized by granulocytosis, lymphopenia, and increased levels of serum-amyloid P and interleukin-6. Within myocardial tissue, MRI relaxometry indicated expansion of extracellular space, most likely due to inflammatory edema and a reduced fluid volume. Accordingly, we found an increased abundance of granulocytes, apoptotic cells, and upregulation of pro-inflammatory cytokines within myocardial tissue following tMCAO. Therefore, reperfused ischemic stroke leads to specific cardiocirculatory alterations that are characterized by acute heart failure with reduced stroke volume, bradycardia, and changes in cardiac tissue and accompanied by systemic and local inflammatory responses.

Troponin Elevation on Admission Along With Dynamic Changes and Their Association With Hemorrhagic Transformation After Thrombolysis

Background: Hemorrhagic transformation (HT) is a common complication of intravenous thrombolysis with alteplase. Cardiac troponin has been found to be associated with poor prognosis and cognitive impairment in acute ischemic stroke. But studies on the relationship between troponin and HT after thrombolysis are scarce. Methods: This study retrospectively analyzed thrombolytic patients from June 2015 to June 2021 in the Second Affiliated Hospital of Wenzhou Medical University. Cardiac troponin I were measured on admission and on following days to determine the presence of elevation and dynamic changes. HT within 24-36 h after treatment was identified by cranial computed tomography (CT). Besides, a score on the modified Rankin Scale (mRS) > 2 at discharge was defined as unfavorable outcome. Univariate analysis was used to explore the factors related to the troponin elevation on admission and troponin dynamic changes. Multivariate logistic regression model was used to investigated the association between troponin elevation on admission, troponin dynamic changes and HT after thrombolysis, respectively. Results: Troponin levels on admission were measured in 377 patients, and follow-up assay was performed in 292 patients (77.5%). 39 patients (10.3%) had troponin elevation on admission, and 66 patients (22.6%) had troponin dynamic changes comprising rising and falling pattern. The pre-existing heart disease, renal insufficiency and higher stroke severity are related to both troponin elevation on admission and the subsequent troponin dynamic changes. After adjusting the potential confounding factors, logistic regression model showed that patients with troponin elevation on admission had insignificant trend to develop HT (OR 2.23, 95%CI 0.96-5.21, p = 0.063), while patients with troponin dynamic changes had significantly higher risk of HT (OR 2.27, 95%CI 1.06-4.85, p = 0.034). Compared to the troponin elevation, a statistically stronger association was present between rising troponin dynamic changes and unfavorable outcome (OR 2.20, 95%CI 1.05-4.60, p = 0.037). Conclusion: Troponin dynamic changes are associated with HT after thrombolysis. Serial measurements are quite necessary in thrombolytic patients with risk factors associated with troponin dynamic changes (e.g., advanced age, pre-existing heart disease, higher NIHSS score, and troponin elevation on admission).

Brain to periphery in acute ischemic stroke: Mechanisms and clinical significance

The social and public health burdens of ischemic stroke have been increasing worldwide. In addition to focal brain damage, acute ischemic stroke (AIS) provokes systemic abnormalities across peripheral organs. AIS profoundly alters the autonomic nervous system, hypothalamic-pituitary-adrenal axis, and immune system, which further yield deleterious organ-specific consequences. Poststroke systemic pathological alterations in turn considerably contribute to the progression of ischemic brain injury, which accounts for the substantial impact of systemic complications on stroke outcomes. This review provides a comprehensive and updated pathophysiological model elucidating the systemic effects of AIS. To address their clinical significance and inform stroke management, we also outline the resulting systemic complications at particular stages of AIS and highlight the mechanisms. Future therapeutic strategies should attempt to integrate the treatment of primary brain lesions with interventions for secondary systemic complications, and should be tailored to patient individualized characteristics to optimize stroke outcomes.

Myocardial injury in acute ischemic stroke

Since antiquity, the interaction of brain and heart has inspired physicians and philosophers. Today, our knowledge has vastly improved, but the exact way of their interaction still holds many secrets to reveal. The interaction between brain and heart merits particular attention in the aftermath of a sudden injury to the brain-like acute ischemic stroke (AIS). This narrative review gives an overview of current knowledge on frequency, prognosis, and potential pathophysiological mechanisms of myocardial injury following AIS.

Atrial Fibrillation and Ischemic Stroke: A Clinical Review

Atrial fibrillation (AF) is an important risk factor for ischemic stroke resulting in a fivefold increased stroke risk and a twofold increased mortality. Our understanding of stroke mechanisms in AF has evolved since the concept of atrial cardiopathy was introduced as an underlying pathological change, with both AF and thromboembolism being common manifestations and outcomes. Despite the strong association with stroke, there is no evidence that screening for AF in asymptomatic patients improves clinical outcomes; however, there is strong evidence that patients with embolic stroke of undetermined source may require long-term monitoring to detect silent or paroxysmal AF. Stroke prevention in patients at risk, assessed by the CHA₂DS₂-VASc score, was traditionally achieved with warfarin; however, direct oral anticoagulants have solidified their role as safe and effective alternatives. Additionally, left atrial appendage exclusion has emerged as a viable option in patients intolerant of anticoagulation. When patients with AF have an acute stroke, the timing of initiation or resumption of anticoagulation for secondary stroke prevention has to be balanced against the risk of hemorrhagic conversion. Multiple randomized clinical trials are currently underway to determine the best timing for administration of anticoagulants following acute ischemic stroke.

[Acute ischemic stroke and elevated troponin: Diagnostic work-up and therapeutic consequences]

Elevated troponin values are frequently detected in patients with acute ischemic stroke, requiring adequate diagnostic work-up due to the high cardiac mortality after stroke. Since dual platelet inhibition can cause secondary intracerebral hemorrhage careful consideration of invasive coronary intervention is mandatory. Based on three case reports, this review article presents a diagnostic algorithm taking into account latest findings from the literature.

Cardiomyocyte Injury Following Acute Ischemic Stroke: Protocol for a Prospective Observational Cohort Study

Background

Elevated cardiac troponin, which indicates cardiomyocyte injury, is common after acute ischemic stroke and is associated with poor functional outcome. Myocardial injury is part of a broad spectrum of cardiac complications that may occur after acute ischemic stroke. Previous studies have shown that in most patients, the underlying mechanism of stroke-associated myocardial injury may not be a concomitant acute coronary syndrome. Evidence from animal research and clinical and neuroimaging studies suggest that functional and structural alterations in the central autonomic network leading to stress-mediated neurocardiogenic injury may be a key underlying mechanism (ie, stroke-heart syndrome). However, the exact pathophysiological cascade remains unclear, and the diagnostic and therapeutic implications are unknown.

Objective

The aim of this CORONA-IS (Cardiomyocyte injury following Acute Ischemic Stroke) study is to quantify autonomic dysfunction and to decipher downstream cardiac mechanisms leading to myocardial injury after acute ischemic stroke.

Methods

In this prospective, observational, single-center cohort study, 300 patients with acute ischemic stroke, confirmed via cerebral magnetic resonance imaging (MRI) and presenting within 48 hours of symptom onset, will be recruited during in-hospital stay. On the basis of high-sensitivity cardiac troponin levels and corresponding to the fourth universal definition of myocardial infarction, 3 groups are defined (ie, no myocardial injury [no cardiac troponin elevation], chronic myocardial injury [stable elevation], and acute myocardial injury [dynamic rise/fall pattern]). Each group will include approximately 100 patients. Study patients will receive routine diagnostic care. In addition, they will receive 3 Tesla cardiovascular MRI and transthoracic echocardiography within 5 days of symptom onset to provide myocardial tissue characterization and assess cardiac function, 20-min high-resolution electrocardiogram for analysis of cardiac autonomic function, and extensive biobanking. A follow-up for cardiovascular events will be conducted 3 and 12 months after inclusion.

Results

After a 4-month pilot phase, recruitment began in April 2019. We estimate a recruitment period of approximately 3 years to include 300 patients with a complete cardiovascular MRI protocol.

Conclusions

Stroke-associated myocardial injury is a common and relevant complication. Our study has the potential to provide a better mechanistic understanding of heart and brain interactions in the setting of acute stroke. Thus, it is essential to develop algorithms for recognizing patients at risk and to refine diagnostic and therapeutic procedures.

Trial Registration

Clinicaltrials.gov NCT03892226; https://www.clinicaltrials.gov/ct2/show/NCT03892226.

International Registered Report Identifier (IRRID)

DERR1-10.2196/24186

Role of Cardiac Biomarkers in the Assessment of Acute Cerebrovascular Accident

Background  Stroke (cerebrovascular accident) has for long been a global burden in terms of its morbidity and mortality. Serum levels of cardiac enzymes such as creatine kinase-MB (CK-MB) component, troponin T, and brain natriuretic peptide have been found to be elevated among the patients with stroke and also serve to prognosticate these patients. The serum levels of these enzymes correlate directly to the severity of stroke in these patients.

Objective  Elevated cardiac enzymes among patients with acute cerebrovascular accidents are not uncommon despite the patients not having any cardiac problems. We aimed to identify the occurrence of elevated cardiac enzymes among patients with acute stroke and their correlation with the severity of stroke.

Materials and Methods  Our study included 100 patients of acute stroke with no previous history of cardiac ailments. Serum levels of troponin I and CK-MB were analyzed among these patients using enzyme-linked immunosorbent assay method within the first 2 hours of admission. Patients outcome during the hospital stay were analyzed. Stroke severity was assessed using the National Institute of Health Stroke score (NIHS score) and the modified Rankin Score (mRS). The cardiac enzyme levels were correlated with these scores.

Results  Twenty-eight percent of patients had elevated troponin I, while 72% patients had normal levels with the mean values of 10.36 to 106.54 ng/mL and 0.00 to 0.02 ng/mL, respectively. CK-MB levels were found elevated among 14% patients and normal among 86% patients with mean values of 5.8 to 124.36 and 0.0 to 4.3 ng/mL, respectively. Among the six patients who succumbed to death, three patients had increased troponin I and four had elevated CK-MB. NIHS scores of 21.0357±6.79 and 105.277±5.564 were seen in patients with elevated and normal troponin I, whereas NIHS scores of 20.4285±8.658 and 11.8721±9.273 were seen among patients with increased and normal CK-MB, respectively. The mRS scores were 4.3214±0.367, 2.4305±1.374, 4.2143±1.412, and 2.756±1.749 ng/mL among the patients with elevated and normal troponin I and CK-MB, respectively.

Conclusion  The mean values of cardiac enzymes troponin I and CK-MB were higher among patients with higher scores of NIHS and mRS. Among them, troponin I was very significant and it may serve as an early biomarker for the severity of stroke and hint on early cardiac evaluation among these patients.

Neurological update: use of cardiac troponin in patients with stroke

Cardiac troponin is a specific and sensitive biomarker to identify and quantify myocardial injury. Myocardial injury is frequently detected after acute ischemic stroke and strongly associated with unfavorable outcomes. Concomitant acute coronary syndrome is only one of several possible differential diagnoses that may cause elevation of cardiac troponin after stroke. As a result, there are uncertainties regarding the correct interpretation and optimal management of stroke patients with myocardial injury in clinical practice. Elevation of cardiac troponin may occur as part of a 'Stroke-Heart Syndrome'. The term 'Stroke-Heart Syndrome' subsumes a clinical spectrum of cardiac complications after stroke including cardiac injury, dysfunction, and arrhythmia which may relate to disturbances of autonomic function and the brain-heart axis. In this review, we provide an up-to-date overview about prognostic implications, mechanisms, and management of elevated cardiac troponin levels in patients with acute ischemic stroke.

Prognostic value of cardiac troponin levels in patients presenting with supraventricular tachycardias

BACKGROUND

An association between paroxysmal supraventricular tachycardias (PSVT) and elevated cardiac troponin I (cTnI) has been reported in small studies, even in the absence of significant coronary artery or structural heart disease. We sought to explore the prognostic significance of elevated cTnI among patients presenting with PSVT.

METHODS

This is a retrospective single-center observational study conducted between January 2014 and Decemebr 2016. 165 patients (60% men, mean age 55 ± 17 year-old) with an acute episode of regular supraventricular tachyarrhythmia were admitted to the emergency department at Rambam Medical Center. 131 patients had at least one serum cTnI value measured. Of those, 57 had a positive result, defined as serum cTnI of more than 0.028 ng/dL.

RESULTS

Multivariate analysis showed that heart rate > 150 beats per minute (bpm) on admission (OR = 3.9; 95% CI 1.1.6-9.5; p < 0.003) and history of coronary artery disease (CAD) (OR = 3.4; 95% CI 1.2-10.1; p = 0.026) were the only independent predictors of cTnI elevation. After mean follow-up period of 23 ± 7 months, the combined primary outcome of death, coronary intervention (PCI) or myocardial infarction (MI) occurred in 7 patients (12.3%) out of 57 patients with positive cTnI and in zero patients with negative cTn (p = 0.002). Cox proportional hazard model showed that elevated cTnI on admission was an independent predictor of adverse outcomes only in patients with known coronary artery disease (CAD) (HR = 3.3, p = 0.05).

CONCLUSION

Elevated cTnI among patients presenting with PSVT appears to have prognostic significance only in patients with history of CAD. In this patient group elevated cTnI is associated with increased risk of adverse cardiac outcomes. We therefore believe serum cTnI should be measured selectively, such as in patients with symptoms of ischemic chest pain and a high pretest likelihood of having CAD.

[Troponin elevation in acute ischemic stroke-unspecific or acute myocardial infarction? : Diagnostics and clinical implications]

Routine determination of troponin levels is recommended for all patients with acute ischemic stroke. In 20-55% of these patients the troponin levels are elevated, which may be caused by ischemic as well as non-ischemic myocardial damage and particularly neurocardiogenic myocardial damage. In patients with acute ischemic stroke, the prevalence of previously unknown coronary heart disease is reported to be up to 27% and is prognostically relevant for these patients; however, relevant coronary stenoses are less frequently detected in stroke patients with troponin elevation compared to patients with non-ST elevation myocardial infarction. The risk of secondary intracerebral hemorrhage due to the necessity for dual platelet aggregation inhibition illustrates the challenging indication for invasive coronary diagnostics and revascularization. Therefore, a diagnostic work-up and interdisciplinary risk evaluation appropriate to the urgency are necessary in order to be able to determine a reasonable treatment approach with timing of the intervention, type and duration of blood thinning. In addition to conventional examination methods, multimodal cardiac imaging is increasingly used for this purpose. This review article aims to provide a pragmatic and clinically oriented approach to diagnostic and therapeutic procedures, taking into account the available evidence.

Prognostic value of elevated cardiac troponin I in patients with intracerebral hemorrhage

Background

Although cardiac troponin has been well established as diagnostic and prognostic makers for acute coronary heart disease, the prognostic value of elevated cardiac troponin in patients with intracerebral hemorrhage (ICH) was inconsistent and not systematically evaluated.

Hypothesis

We proposed the hypothesis that the practical utility of cardiac troponin levels for prediction of mortality and poor outcome in ICH patients.

Methods

A total of 1004 patients with ICH were retrospectively reviewed and qualified for further analysis from June 2012 to December 2015. The patients were divided into different groups based on measurements of cardiac troponin I (cTnI) at the time of admission and the following day. Multivariate Cox proportional hazards analysis were performed to determine the independent prognostic value of the cTnI for patients in‐hospital mortality and poor outcomes, the receiver operator characteristic (ROC) analysis was performed to assess the predictive value of cTnI, ICH score, and combination of them.

Results

Serum cTnI level was an independent predictor in‐hospital mortality (positive vs negative, HR (hazard ratios) = 3.44, 95% CI (confidence interval) 1.66‐7.13, P < .001) and poor outcomes in patients with ICH (positive vs negative, HR = 6.69, 95% CI 4.25‐10.52, P < .001). Addition of cTnI to ICH score significantly improved the prognostic discrimination for both in‐hospital mortality and poor outcomes.

Conclusion

Serum cTnI levels may be valuable as predictor for in hospital mortality and poor outcomes and may be useful in the risk stratification of ICH during hospitalization.

Troponin T Predicts Cardioembolic Aetiology and Clinical Outcome in Undetermined Ischaemic Stroke in Hyperacute Phase

BACKGROUND

Elevated high-sensitivity cardiac troponin T (hs-cTnT) levels have been related to clinical outcome in stroke patients. However, the role of hs-cTnT and its potential as a biomarker in ischaemic stroke (IS) has not been well established. This study aims to determine whether basal hs-cTnT determination in the hyperacute phase of undetermined IS and transient ischaemic attack (TIA) can predict the cardioembolic aetiology and clinical outcome.

METHODS

We prospectively studied 110 consecutive patients with undetermined acute IS and TIA. hs-cTnT levels were determined at hospital arrival. Large vessel stenosis/occlusion and previously known aetiologies at admission were exclusion criteria for this study. All patients were subjected to a complete aetiological evaluation. A 12-month follow-up was performed in all patients. The subtype of IS was evaluated following the SSS-TOAST criteria. We established two groups at admission: cardioembolic aetiology (group A) and noncardioembolic aetiologies (group B).

RESULTS

The number of patients in each group was similar (group A: 52, 47.27%; group B, 58, 52.73%). Patients in group A had elevated hs-cTnT more frequently (61.54% versus 17.24%; P < .001). Group A patients had significantly higher mortality at 3 months (14.29% versus 1.82%, P = .025). In the multivariate analysis, elevated hs-cTnT was the only independent predictor of cardioembolic aetiology (odds ratio: 14.821; 95% confidence interval: 3.717-59.102, P < .001).

CONCLUSION

Baseline hs-cTnT assessment in undetermined strokes and TIA during the hyperacute phase is independently associated with cardioembolic aetiology.

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.

Challenges in high-sensitive troponin assay interpretation for intensive therapy

Cardiac troponins T and I are considered highly sensitive and specific markers for the diagnosis of acute myocardial infarction. Currently, a series of nonprimary cardiac abnormalities may manifest as an elevation in high-sensitive assays. The reduction in their detection limits has allowed earlier diagnosis and the use of evidence-based therapeutic measures; however, this characteristic has increased the spectrum of detectable noncoronary heart diseases, which poses challenges for characterizing acute coronary syndromes and creates a new role for these tests in known disorders in intensive care units, especially sepsis. Management of patients through a greater understanding of how these markers behave should be re-evaluated to ensure their correct interpretation.

Baseline Troponin T level in stroke and its association with stress cardiomyopathy

BACKGROUND

Differential diagnosis of elevated high sensitive Troponin T (hsTnT) in acute ischemic stroke includes myocardial infarction (MI) and neurogenic stunned myocardium (NSM). The aim of this study was to identify factors associated with baseline hsTnT levels and MI or NSM in acute ischemic stroke.

METHODS

We studied 204 consecutive patients of the prospective acquired Bern Stroke Database with acute ischemic stroke diagnosed by brain MR. All patient histories and cardiac examinations were reviewed retrospectively. Volumetry of lesions on diffusion and perfusion weighted brain imaging (circular singular value decomposition, Tmax >6sec) was performed. Voxel based analysis was performed to identify brain areas associated with hsTnT elevation. Linear regression analysis was used to identify predictors of baseline hsTnT levels and myocardial infarction.

RESULTS

Elevated hsTnT was observed in 58 of the 204 patients (28.4%). The mean age was 68.3 years in the normal hsTnT group and 69.7 years in the elevated hsTnT group. Creatinine (p<0.001, OR 6.735, 95% CI 58.734-107.423), baseline NIHSS score (p = 0.029, OR 2.207, 95% CI 0.675-12.096), ST segment depression (p = 0.025, OR 2.259, 95% CI 2.419-35.838), and negative T waves in baseline ECG (p = 0.002, OR 3.209, 95% CI 13.007-54.564) were associated with hsTnT elevation, while infarct location and size were not. Coronary angiography was performed in 30 of the 204 patients (14.7%) and myocardial infarction was diagnosed in 7 of them (23.3%). Predictive factors for myocardial infarction could not be identified.

CONCLUSION

Elevated baseline baseline hsTnT was associated with NIHSS, creatinine, ST segment depression and inverted T waves, but not with stroke location or size. None of the factors was helpful to differentiate MI and NSM. Therefore, ancillary investigations such as coronary angiography, cardiac MRI or both may be needed to solve the differential diagnosis.

Cardiac troponin for predicting all-cause mortality in patients with acute ischemic stroke: a meta-analysis

Cardiac troponins are specific biomarkers of cardiac injury. However, the prognostic usefulness of cardiac troponin in patients with acute ischemic stroke is still controversial. The objective of this meta-analysis was to investigate the association of cardiac troponin elevation with all-cause mortality in patients with acute ischemic stroke. PubMed and Embase databases were searched for relevant studies up to April 31, 2017. All observational studies reporting an association of baseline cardiac troponin-T (cTnT) or troponin-I (cTnI) elevation with all-cause mortality risk in patients with acute ischemic stroke were included. Pooled adjusted risk ratio (RR) and corresponding 95% confidence interval (CI) were obtained using a random effect model. Twelve studies involving 7905 acute ischemic stroke patients met our inclusion criteria. From the overall pooled analysis, patients with elevated cardiac troponin were significantly associated with increased risk of all-cause mortality (RR: 2.53; 95% CI: 1.83-3.50). The prognostic value of cardiac troponin elevation on all-cause mortality risk was stronger (RR: 3.54; 95% CI: 2.09-5.98) during in-hospital stay. Further stratified analysis showed elevated cTnT (RR: 2.36; 95% CI: 1.47-3.77) and cTnI (RR: 2.79; 95% CI: 1.68-4.64) level conferred the similar prognostic value of all-cause mortality. Acute ischemic stroke patients with elevated cTnT or cTnI at baseline independently predicted an increased risk of all-cause mortality. Determination of cardiac troponin on admission may aid in the early death risk stratification in these patients.

Relationship between Cardiac Troponin and Thrombo-Inflammatory Molecules in Prediction of Outcome after Acute Ischemic Stroke

BACKGROUND

In patients with acute ischemic stroke (AIS) without cardiovascular complications, we investigated the association of serum concentration of cardiac troponin (high-sensitivity cardiac troponin T [hs-cTnT]) with thrombo-inflammatory markers.

METHODS

Thirty-five patients with first-ever AIS were prospectively examined. Serum hs-cTnT was measured 6 and 24 hours after stroke, whereas S100B, high-sensitivity C-reactive protein (hsCRP), soluble CD40 ligand, tissue plasminogen activator (tPA), monocyte chemoattractant protein-1 (MCP-1), and P-selectin were measured 6 and 72 hours after stroke. Severity of stroke was assessed by the National Institutes of Health Stroke Scale (NIHSS) on admission, 24 hours later, and at discharge.

RESULTS

Concentration of MCP-1 at 6 hours was higher in the serum of patients with worsened NIHSS by 24 hours (P = .009). Concentration of hs-cTnT at both 6 and 24 hours was higher, if NIHSS worsened by discharge (P = .026 and P = .001). A cutoff value for hs-cTnT measured at T24 greater than or equal to  9.4 predicted worsened NIHSS on discharge with a sensitivity of 81% and a specificity of 74% (area: .808, P = .002). Concentration of hs-cTnT at both 6 and 24 hours was also higher in nonsurvivors compared with survivors (P = .03, respectively), and correlated with (1) tPA levels at 6 hours (P = .001 and P = .002, respectively); (2) MCP-1 concentration at 6 hours (P = .01 and P = .015, respectively); and increased hsCRP levels at 72 hours (P = .01, respectively). Concentration of hs-cTnT at 24 hours was an independent predictor of worsened NIHSS at discharge (odds ratio: 1.58, 95% confidence interval: 1.063-2.370, P = .024).

CONCLUSIONS

Elevated concentration of hs-cTnT measured 24 hours after AIS is an independent predictor of progressing neurologic deficit in patients without apparent myocardial damage, and also correlates with acute elevation of tPA and MCP-1.

Prevalence of Positive Troponin and Echocardiogram Findings and Association With Mortality in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Acute ischemic stroke (AIS) patients may have raised serum cardiac troponin levels on admission, although it is unclear what prognostic implications this has, and whether elevated levels are associated with cardiac causes of stroke or structural cardiac disease as seen on echocardiogram. We investigated the positivity of cardiac troponin and echocardiogram testing within a large biracial AIS population and any association with poststroke mortality.

METHODS

Within a catchment area of 1.3 million, we screened emergency department admissions from 2010 using International Classification of Diseases, Ninth Edition, discharge codes 430 to 436 and ascertained all physician-confirmed AIS cases by retrospective chart review. Hypertroponinemia was defined as elevation in cardiac troponin above the standard 99th percentile. Multiple logistic regression was performed, controlling for stroke severity, history of cardiac disease, and all other stroke risk factors.

RESULTS

Of 1999 AIS cases, 1706 (85.3%) had a cardiac troponin drawn and 1590 (79.5%) had echocardiograms. Hypertroponinemia occurred in 353 of 1706 (20.7%) and 160 of 1590 (10.1%) had echocardiogram findings of interest. Among 1377 who had both tests performed, hypertroponinemia was independently associated with echocardiogram findings (odds ratio, 2.9; 95% confidence interval, 2-4.2). When concurrent myocardial infarctions (3.5%) were excluded, hypertroponinemia was also associated with increased mortality at 1 year (35%; odds ratio, 3.45; 95% confidence interval, 2.1-5.6) and 3 years (60%; odds ratio, 2.91; 95% confidence interval, 2.06-4.11).

CONCLUSIONS

Hypertroponinemia in the context of AIS without concurrent myocardial infarction was associated with structural cardiac disease and long-term mortality. Prospective studies are needed to determine whether further cardiac evaluation might improve the long-term mortality rates seen in this group.

[Interaction between heart and brain in sudden cardiac death]

The heart and brain are constantly interacting under normal physiological conditions. This interaction is under the control of the autonomic nervous system with parasympathetic and sympathetic nerve fibers including the participating brain structures. Pathological conditions, such as epilepsy and ischemic cerebral stroke influence heart function, especially the frequency and may result in severe arrhythmia. An asymmetric influence of the left and right brain hemispheres on the heart rate is still under debate. Conversely, the influence of the heart in cases of acute cardiac arrest on brain function is equally relevant and a common clinical problem after resuscitation. We review the damaging cascade of global cerebral hypoxia and the value of different diagnostic procedures as well as the ethical problem of the point in time of termination of consciousness and the instruments for estimating the prognosis.

Elevated troponin in patients with acute stroke - Is it a true heart attack?

Although the prognostic value of a positive troponin in an acute stroke patient is still uncertain, it is a commonly encountered clinical situation given that Ischemic Heart Disease (IHD) and cerebrovascular disease (CVD) frequently co-exist in the same patient and share similar risk factors. Our objectives in this review are to (1) identify the biologic relationship between acute cerebrovascular stroke and elevated troponin levels, (2) determine the pathophysiologic differences between positive troponin in the setting of acute stroke versus acute myocardial infarction (AMI), and (3) examine whether positive troponin in the setting of acute stroke has prognostic significance. We also will provide an insight analysis of some of the available studies and will provide guidance for a management approach based on the available data according to the current guidelines.

Application of Cardiac Troponin in Cardiovascular Diseases Other Than Acute Coronary Syndrome

BACKGROUND

Increased cardiac troponin concentrations in acute coronary syndrome (ACS) identify patients with ongoing cardiomyocyte necrosis who are at increased risk. However, with the use of more precise assays, cardiac troponin increases are commonly noted in other cardiovascular conditions as well. This has generated interest in the use of cardiac troponin for prognostic assessment and clinical management of these patients. In this review, we have summarized the data from studies investigating the implications of cardiac troponin concentrations in various acute and chronic conditions beyond ACS, i.e., heart failure, myocarditis, Takotsubo cardiomyopathy, aortic dissection, supraventricular arrhythmias, valve disease, pulmonary arterial hypertension, stroke, and in the perioperative setting.

CONTENT

Cardiac troponin concentrations are often detectable and frankly increased in non-ACS conditions, in particular when measured with high-sensitivity (hs) assays. With the exception of myocarditis and Takotsubo cardiomyopathy, cardiac troponin concentrations carry strong prognostic information, mainly with respect to mortality, or incipient and/or worsening heart failure. Studies investigating the prognostic benefit associated with cardiac troponin–guided treatments however, are almost lacking and the potential role of cardiac troponin in the management of non-ACS conditions is not defined.

SUMMARY

Increased cardiac troponin indicates increased risk for adverse outcome in patients with various cardiovascular conditions beyond ACS. Routine measurement of cardiac troponin concentrations can however, not be generally recommended unless there is a suspicion of ACS. Nonetheless, any finding of an increased cardiac troponin concentration in a patient without ACS should at least prompt the search for possible underlying conditions and these should be managed meticulously according to current guidelines to improve outcome.

Internal associations and dynamic expression of c-kit and nanog genes in ventricular remodelling induced by adriamycin

The present study aimed to investigate the dynamic expression of the c-kit and nanog genes in rats with left ventricular remodelling induced by adriamycin (ADR), and explore its internal association and mechanism of action. Sprague-Dawley male rats were randomly divided into a normal control group and a heart failure model group. Heart failure was induced by a single intraperitoneal injection of ADR (4 mg/kg) weekly for six weeks. The normal control group was given the same amount of saline. At the eighth week, rat cardiac function was examined to demonstrate the formation of heart failure. The rat hearts were harvested frozen and sectioned, and the expression levels of the nanog and c-kit genes in the myocardial tissue samples were detected using immunohistochemistry, immunofluorescence and reverse transcription-polymerase chain reaction (RT-PCR). Hematoxylin and eosin staining demonstrated various pathological changes in the myocardial cells in the heart failure model group, whereas myocardial infarction was not observed in the normal control group. Immunohistochemistry and immunofluorescence demonstrated that nanog-positive cells were predominantly expressed in the vascular endothelium, with a few myocardial cells and stem cells in normal myocardium. The expression levels of c-kit and nanog in the myocardium of the rats with heart failure decreased significantly. c-kit-positive cells clustered together in the epicardium and its vicinity, and c-kit expression significantly decreased in the myocardium of rats with heart failure, as compared with normal rats. In both groups, some cells co-expressed both the c-kit and nanog genes. The RT-PCR results demonstrated that the expression levels of the two genes in the heart failure model group were significantly lower compared with those in the normal control group (P<0.05). In conclusion, the c-kit- and nanog-positive stem cells decreased in the myocardium of the rats with left ventricular remodelling induced by ADR. Their abnormal expression was significantly correlated with left ventricular remodelling, thereby indicating an internal association (influences of two indexes in the experimental group and control group) between them.

Admission troponin-I predicts subsequent cardiac complications and mortality in acute stroke patients

Purpose

The importance of troponin elevation at stroke presentation remains uncertain. We aimed to assess whether baseline ultrasensitive Troponin I (hs-TnI) predicts cardiac complications and outcome in acute stroke patients.

Method

Stroke patients admitted within 6 h were consecutively enrolled from May 2013 to March 2014. Blood samples were taken at admission to determine hs-TnI by chemiluminescent microparticle immunoassay. hs-TnI > 34.2 pg/ml (male) and >15.6 pg/ml (female) were considered elevated. Complications during in-hospital stay and outcome at 90 days were prospectively recorded. Independent predictors of cardiac complications (heart failure and acute coronary syndrome) and mortality were determined by logistic regression. The additional predictive value of hs-TnI was evaluated by integrated discrimination improvement index. A subanalysis was performed after excluding patients with previous cardiac diseases.

Findings

From 174 patients, 39(22%) had elevated hs-TnI, having these patients higher incidence of cardiac complications (57% versus 19%, p = 0.004). hs-TnI was an independent predictor of cardiac complications (OR = 16.1 (1.7-150.3)) together with diastolic blood pressure (OR = 0.92 (0.86-0.99)). Addition of hs-TnI to clinical variables significantly improved discrimination (IDI = 15.2% (7.8-22.7)). Subanalysis in patients without previous cardiac diseases showed similar results. Elevated hs-TnI was independently associated with 90 days mortality (OR = 3.6 (1.3-9.4)), but addition of hs-TnI to clinical data did not result in an increased discrimination.

Discussion

The present study confers hs-TnI a 2b level of evidence as a diagnostic tool to predict cardiac complications in stroke. Absence of serial hs-TnI measurements and limited sample size are the main weaknesses of the study.

Conclusion

Patients with elevated baseline hs-TnI showed a higher frequency of cardiac complications and a higher mortality. Measurement of hs-TnI in acute stroke might be useful to identify patients at a high risk of cardiac complications and death.

Association between Intraoperative Hypotension and Myocardial Injury after Vascular Surgery

BACKGROUND

Postoperative myocardial injury occurs frequently after noncardiac surgery and is strongly associated with mortality. Intraoperative hypotension (IOH) is hypothesized to be a possible cause. The aim of this study was to determine the association between IOH and postoperative myocardial injury.

METHODS

This cohort study included 890 consecutive patients aged 60 yr or older undergoing vascular surgery from two university centers. The occurrence of myocardial injury was assessed by troponin measurements as part of a postoperative care protocol. IOH was defined by four different thresholds using either relative or absolute values of the mean arterial blood pressure based on previous studies. Either invasive or noninvasive blood pressure measurements were used. Poisson regression analysis was used to determine the association between IOH and postoperative myocardial injury, adjusted for potential clinical confounders and multiple comparisons.

RESULTS

Depending on the definition used, IOH occurred in 12 to 81% of the patients. Postoperative myocardial injury occurred in 131 (29%) patients with IOH as defined by a mean arterial pressure less than 60 mmHg, compared with 87 (20%) patients without IOH (P = 0.001). After adjustment for potential confounding factors including mean heart rates, a 40% decrease from the preinduction mean arterial blood pressure with a cumulative duration of more than 30 min was associated with postoperative myocardial injury (relative risk, 1.8; 99% CI, 1.2 to 2.6, P < 0.001). Shorter cumulative durations (less than 30 min) were not associated with myocardial injury. Postoperative myocardial infarction and death within 30 days occurred in 26 (6%) and 17 (4%) patients with IOH as defined by a mean arterial pressure less than 60 mmHg, compared with 12 (3%; P = 0.08) and 15 (3%; P = 0.77) patients without IOH, respectively.

CONCLUSIONS

In elderly vascular surgery patients, IOH defined as a 40% decrease from the preinduction mean arterial blood pressure with a cumulative duration of more than 30 min was associated with postoperative myocardial injury.

Factors underlying elevated troponin I levels following pacemaker primo-implantation

BACKGROUND

Cardiac troponins are routinely used as markers of myocardial damage. Originally, they were only intended for use in diagnosing acute coronary syndromes; however, we now know that raised serum troponin levels are not always caused by ischemia. There are many other clinical conditions that cause damage to cardiomyocytes, leading to raised levels of troponin. However, the specificity of cardiac troponins towards the myocardium is absolute. Our work focuses on mechanical damage to the myocardium and on monitoring the factors that raise the levels of cardiospecific markers after primo-implantation of a pacemaker with an actively fixed electrode.

AIMS

(i) To determine whether the use of a primo-implanted pacemaker with an electrode system with active fixation will raise troponin levels over baseline. (ii) To assess whether troponin I elevation is dependent on procedure complexity.

METHODS

We enrolled 219 consecutive patients indicated for pacemaker primo-implantation; cardiospecific marker values (troponin I, CKMB, myoglobin) were determined before the implantation procedure and again at 6- and 18-h intervals after the procedure. We monitored duration of cardiac skiascopy, number of attempts to place the electrode (active penetration into the tissue) and intervention range (single-chamber versus dual-chamber pacing), and we assessed the clinical data.

RESULTS

The average age of the enrolled patients was 78.2 ± 8.0 years (median age, 80 years); women constituted 45% of the group. We implanted 128 dual-chamber and 91 single-chamber devices with an average skiascopic time of 38.6 ± 22.0 s (median, 33.5 s). Troponin I serum levels increased from an initial 0.03 ± 0.07 μg/L (median, 0.01) to 0.18 ± 0.17 μg/L (median, 0.13) and 0.09 ± 0.18 μg/L (median, 0.04) at 6 and 18 h, respectively. The differences were statistically significant (P < 0.001 or P < 0.001). We confirmed a correlation between troponin increase and duration of skiascopy (P < 0.001). We also demonstrated a correlation between increased troponin I and number of attempts to place a pacemaker electrode (penetration into the tissue) at 6 h (P < 0.001) post-implantation.

CONCLUSION

We detected slightly elevated troponin I levels in patients with primo-implanted pacemakers using electrodes with active fixation. We demonstrated a direct correlation between myocardial damage (number of electrode penetrations into the myocardium) and troponin I elevation, as well as between complexity (severity) of the implantation procedure (indicated by prolonged skiascopy) and raised troponin I. The described phenomenon demonstrates the loss of the diagnostic role of troponin I early after pacemaker primo-implantation in patients with concomitant chest pain.

[Troponin elevation in ischemic stroke patients]

Cerebrovascular and cardiovascular diseases are major causes of death and disability worldwide. Ischemic stroke is a frequent complication in cardiac diseases and, vice versa, cardiac complications commonly cause early clinical worsening and death after stroke. In the emergency setting, cardiac biomarkers (preferably troponin, cTn) are measured frequently in patients presenting with acute ischemic stroke. The measurement of cTn is recommended by the guidelines for early management of patients with acute ischemic stroke from the American Heart Association. In case of pathologic cTn elevation, physicians are confronted with diagnostic and therapeutic uncertainties. Up-to-date recommendations on interpretation and consecutive actions remain ambiguous because cTn elevations may originate from causes other than acute coronary disease and because clinical signs and symptoms of acute coronary disease may be obscured by neurological deficits of the stroke. The application of modern, high-sensitive cTn assays that detect even minor cTn elevations has rather aggravated the dilemma of how to interpret this finding in patients with ischemic stroke.This article gives an overview on possible mechanisms of the frequently observed cTn elevation in ischemic stroke patients and offers help on interpretation and meaningful actions.

[Acute coronary syndrome in acute stroke]

BACKGROUND

Elevated troponin levels are commonly found in patients with acute stroke and approximately 60 % of stroke patients suffer from an accompanying coronary artery disease. Troponin release can be caused either by an acute thrombotic myocardial infarction or by insufficient coronary perfusion due to neurocardiogenic causes like blood pressure or heart rate variability without thrombotic coronary occlusion. Due to the often unclear pathological cause of troponin release and the risk of secondary hemorrhage during dual antiplatelet therapy, the determination of the best time point for coronary diagnostics and therapy in stroke patients is a common challenge in clinical daily routine.

MATERIALS AND METHODS

Based on the current literature, we describe a potential diagnostic and therapeutic approach in stroke patients with increased troponin levels.

RESULTS

First, the probability of an acute thrombotic myocardial infarction should be evaluated based on clinical, laboratory, and electrocardiographic parameters. In case of suspected myocardial infarction, a diagnostic coronary angiography/CT angiography should be performed and dual antiplatelet therapy should be given depending on the intracranial bleeding risk. In patients with high risk of intracranial bleeding, thrombus aspiration and balloon dilatation should be considered.

CONCLUSION

In patients with acute stroke and elevated troponin levels, a thorough diagnostic workup is necessary to estimate the probability for a thrombotic myocardial infarction and to prevent cardiac and neurologic complications.

The prognostic significance of troponin I elevation in acute ischemic stroke

BACKGROUND

The significance of cardiac troponin I (TnI) levels in patients with acute ischemic stroke remains unclear.

METHODS

Data were prospectively collected on 1718 patients with acute ischemic stroke (2009-2010). Patients with positive TnI (peak TnI ≥0.1 μg/L) were assigned to the myocardial infarction (MI) group if they met diagnostic criteria. The remaining patients with positive TnI were assigned to the no-MI group. Patients were followed up for 1.4 ± 1.1 years. Primary outcome was inhospital and long-term all-cause mortality.

RESULTS

Positive TnI was present in 309 patients (18%), 119 of whom (39%) were classified as having MI. Positive TnI was independently associated with older age, hypertension, smoking, peripheral arterial disease, heart failure, higher systolic blood pressure, higher serum creatinine, and lower heart rate (P < .01). Patients with MI had the highest inpatient mortality (P < .001) and the lowest survival rate by Kaplan-Meier analysis (P < .0001). Peak TnI greater than or equal to 0.5 μg/L, particularly if satisfying criteria for MI, was independently associated with long-term mortality (P < .0001); peak TnI less than 0.5 μg/L alone was not when adjusted for covariates.

CONCLUSION

Positive TnI greater than or equal to 0.5 μg/L in patients with acute ischemic stroke was independently associated with worse outcomes. Patients with diagnosis of MI represent a particularly high-risk subgroup.

Albumin Administration in Acute Ischemic Stroke: Safety Analysis of the ALIAS Part 2 Multicenter Trial

Background

Albumin treatment of ischemic stroke was associated with cardiopulmonary adverse events in previous studies and a low incidence of intracranial hemorrhage. We sought to describe the neurological and cardiopulmonary adverse events in the ALIAS Part 2 Multicenter Trial.

Methods

Ischemic stroke patients, aged 18–83 and a baseline NIHSS ≥ 6, were randomized to treatment with ALB or saline control within 5 hours of stroke onset. Neurological adverse events included symptomatic intracranial hemorrhage, hemicraniectomy, neurological deterioration and neurological death. Cardiopulmonary adverse events included pulmonary edema/congestive heart failure, acute coronary syndromes, atrial fibrillation, pneumonia and pulmonary thromboembolism.

Results

Among 830 patients, neurological and cardiopulmonary adverse events were not differentially associated with poor outcome between ALB and saline control subjects. The rate of symptomatic intracranial hemorrhage in the first 24h was low overall (2.9%, 24/830) but more common in the ALB treated subjects (RR = 2.4, CI₉₅ 1.01–5.8). The rate of pulmonary edema/CHF in the first 48h was 7.9% (59/830) and was more common among ALB treated subjects (RR = 10.7, CI₉₅ 4.3–26.6); this complication was expected and was satisfactorily managed with mandated diuretic administration and intravenous fluid guidelines. Troponin elevations in the first 48h were common, occurring without ECG change or cardiac symptoms in 52 subjects (12.5%).

Conclusions

ALB therapy was associated with an increase in symptomatic ICH and pulmonary edema/congestive heart failure but this did not affect final outcomes. Troponin elevation occurs routinely in the first 48 hours after acute ischemic stroke.

Trial Registration

ClincalTrials.gov NCT00235495

Cardiac troponin-I on diagnosis predicts early death and refractoriness in acquired thrombotic thrombocytopenic purpura. Experience of the French Thrombotic Microangiopathies Reference Center

BACKGROUND

Cardiac involvement is a major cause of mortality in patients with thrombotic thrombocytopenic purpura (TTP). However, diagnosis remains underestimated and delayed, owing to subclinical injuries. Cardiac troponin-I measurement (cTnI) on admission could improve the early diagnosis of cardiac involvement and have prognostic value.

OBJECTIVES

To assess the predictive value of cTnI in patients with TTP for death or refractoriness.

PATIENTS/METHODS

The study involved a prospective cohort of adult TTP patients with acquired severe ADAMTS-13 deficiency (< 10%) and included in the registry of the French Reference Center for Thrombotic Microangiopathies. Centralized cTnI measurements were performed on frozen serum on admission.

RESULTS

Between January 2003 and December 2011, 133 patients with TTP (mean age, 48 ± 17 years) had available cTnI measurements on admission. Thirty-two patients (24%) had clinical and/or electrocardiogram features. Nineteen (14.3%) had cardiac symptoms, mainly congestive heart failure and myocardial infarction. Electrocardiogram changes, mainly repolarization disorders, were present in 13 cases. An increased cTnI level (> 0.1 μg L(-1) ) was present in 78 patients (59%), of whom 46 (59%) had no clinical cardiac involvement. The main outcomes were death (25%) and refractoriness (17%). Age (P = 0.02) and cTnI level (P = 0.002) showed the greatest impact on survival. A cTnI level of > 0.25 μg L(-1) was the only independent factor in predicting death (odds ratio [OR] 2.87; 95% confidence interval [CI] 1.13-7.22; P = 0.024) and/or refractoriness (OR 3.03; 95% CI 1.27-7.3; P = 0.01).

CONCLUSIONS

A CTnI level of > 0.25 μg L(-1) at presentation in patients with TTP appears to be an independent factor associated with a three-fold increase in the risk of death or refractoriness. Therefore, cTnI level should be considered as a prognostic indicator in patients diagnosed with TTP.

Troponin-I is a predictor of a delayed diagnosis of atrial fibrillation in acute ischemic stroke and transient ischemic attack

BACKGROUND

Prolonged cardiac monitoring detects higher rates of atrial fibrillation (AF) in ischemic stroke and transient ischemic attack (TIA) but is costly and has practical implications. The use of admission troponin-I (TnI) level to identify patients at high risk of delayed AF detection was investigated.

METHODS

Consecutive ischemic stroke and TIA cases presenting to our institute over a 13-month period were identified from the Irish Stroke and TIA Register. Electronic databases and case notes were examined. "Delayed" AF was diagnosed after a sinus rhythm admission electrocardiogram and no documented history. Group comparisons were made by AF status. The association between TnI and AF was investigated using a multivariate regression model.

RESULTS

A total of 185 cases (130 ischemic stroke) were analyzed. Mean age (standard deviation) was 73.3 (13.9) years, 47% female. Sixty-two cases (33.5%) had AF. The first documented presentation of AF was found in 21 cases, on admission electrocardiogram (n = 11) or inpatient telemetry (delayed, n = 10). TnI was higher in those with delayed AF than in those without AF (W = 194; P = .036). A higher proportion of those with an elevated TnI (30%) than those with a normal TnI (6.1%) had delayed diagnosis of AF (χ(2) = 6.41, P = .011). Having an abnormal TnI was a significant independent predictor of delayed AF detection (odds ratio, 5.8; P = .037).

CONCLUSIONS

TnI elevation is associated with a higher likelihood of subsequent AF diagnosis. Identification of these higher risk stroke and TIA cases for more intensive cardiac monitoring may improve stroke secondary prevention practices.