Prognostic relevance of cardiac troponin T levels and their dynamic changes measured with a high-sensitivity assay in acute ischaemic stroke: Analyses from the TRELAS cohort

Acute Myocardial Injury in Spontaneous Intracerebral Hemorrhage: A Secondary Observational Analysis of the FAST Trial

BACKGROUND

Acute myocardial injury is associated with poor outcomes in patients with acute ischemic stroke, but its prognostic significance in patients with spontaneous intracerebral hemorrhage remains unclear. We investigated whether acute myocardial injury and the direction of the cardiac troponin I (cTnI) change (rising versus falling) affect post-intracerebral hemorrhage outcomes.

METHODS AND RESULTS

We re-analyzed the FAST (Factor-Seven-for-Acute-Hemorrhagic-Stroke) trial. Acute myocardial injury was defined as at least 1 cTnI value above the upper reference limit with a rise/fall of >20%. Logistic regression tested for associations (1) between acute myocardial injury (presence versus absence) and poor outcome (modified Rankin Scale 4-6) and mortality at 15 and 90 days; (2) among 3 groups (rising versus falling versus no acute myocardial injury) and outcomes. Among the 841 FAST participants, 785 patients were included. Acute myocardial injury was detected in 29% (n=227); 170 had rising cTnI. At 15 and 90 days, respectively, those with acute myocardial injury had higher odds of poor outcome (adjusted odds ratio) ([aOR] 2.3 [95% CI, 1.3-3.9]); and adjusted odds ratio 2.5 [95% CI, 1.6-3.9];, and higher odds of mortality (adjusted odds ratio 2.4 [95% CI, 1.4-4.3]; and adjusted odds ratio 2.2 [CI, 1.3-3.6]) than patients without. There was no interaction between FAST group assignment and myocardial injury, and associations between myocardial injury and outcomes were consistent across group assignments. Rising cTnI was associated with the highest risk of poor outcomes and mortality.

CONCLUSIONS

In this secondary analysis of the FAST trial, acute myocardial injury was common and associated with poor outcomes. The direction of the cTnI change might provide additional risk stratification after intracerebral hemorrhage.

Role of Cardiac Biomarkers in Stroke and Cognitive Impairment

This topical review assesses the growing role of cardiac biomarkers beyond cardiovascular health and focuses on their importance in stroke and dementia. The first part describes blood-based cardiac biomarkers in patients with stroke and highlights applications in the setting of early diagnosis, poststroke complications, outcome prediction as well as secondary prevention. Among other applications, natriuretic peptides can be helpful in differentiating stroke subtypes. They are also currently being investigated to guide prolonged ECG monitoring and secondary prevention in patients with stroke. Elevated cardiac troponin after ischemic stroke can provide information about various poststroke complications recently termed the stroke-heart syndrome. The second part focuses on the role of cardiac biomarkers in vascular cognitive impairment and dementia, emphasizing their association with structural brain lesions. These lesions such as silent brain infarcts and white matter hyperintensities often co-occur with cardiac disease and may be important mediators between cardiovascular disease and subsequent cognitive decline. ECG and echocardiogram measurements, in addition to blood-based biomarkers, show consistent associations with vascular brain changes and incident dementia, suggesting a role in indicating risk for cognitive decline. Together, the current evidence suggests that cardiac blood-based, electrophysiological, and imaging biomarkers can be used to better understand the heart and brain connection in the setting of not only stroke but also dementia.

Catecholamines-based myocardial injury after acute ischemic stroke and effects of Naoxintong capsule therapy

BACKGROUND

Myocardial injury (MI) after acute ischemic stroke (AIS) poses a significant threat to patient prognosis. However, effective intervention strategies are currently lacking.

PURPOSE

To elucidate the mechanism of MI after AIS and effects of Naoxintong capsule (NXT) therapy.

METHOD

In vivo, after a rat model of middle cerebral artery occlusion (MCAO)-induced MI was established and assessed. NXT was administered prophylactically to evaluate its pharmacodynamic effects and mechanisms. In vitro, a noradrenaline (NA)-induced damage cell model was constructed. Subsequently, the NXT was applied to the cell models to examine its cardioprotective effects and potential mechanisms.

RESULTS

The in vivo findings revealed that following MCAO, there was a notable upregulation of TH expression in the rat brain, which subsequently triggered an increase in serum levels of various biomarkers, including AD, NA, AST, cTnT, CK-MB, and NT-proBNP. Histological analysis employing H&E staining and TUNEL assay disclosed significant pathological alterations and an escalation in apoptotic activity within the myocardial tissue. The myocardial tissue exhibited elevated levels of MDA alongside diminished CAT activity. Additionally, a marked increase in the Bax/Bcl-2 ratio, Cytochrome C release, and Caspase-3 activation was observed, all of which are indicative of heightened apoptotic activity. Administration of the NXT intervention successfully attenuated TH expression in the brains of rats subjected to MCAO, consequently leading to a reduction in circulating levels of catecholamines (CAs). NXT also exhibited significant efficacy at ameliorating cardiac oxidative stress and reducing apoptosis. In vitro, stimulation with NA led to an increase in ROS levels and calcium ion concentration in H9c2 cardiomyocytes. However, the administration of NXT has been found to effectively alleviate these adverse effects, thereby protecting H9c2 cardiomyocytes from the deleterious consequences of oxidative stress and calcium dyshomeostasis.

CONCLUSION

Overall, this study has demonstrated that increased CAs synthesis in the brain after AIS in experimental rats led to a surge in circulating CAs, ultimately leading to MI. NXT can alleviate MI due to cerebral ischemia by increasing improving brain catecholamine synthesis, cardiac oxidative stress, and apoptosis.

Stroke-heart syndrome: current progress and future outlook

Stroke can lead to cardiac complications such as arrhythmia, myocardial injury, and cardiac dysfunction, collectively termed stroke-heart syndrome (SHS). These cardiac alterations typically peak within 72 h of stroke onset and can have long-term effects on cardiac function. Post-stroke cardiac complications seriously affect prognosis and are the second most frequent cause of death in patients with stroke. Although traditional vascular risk factors contribute to SHS, other potential mechanisms indirectly induced by stroke have also been recognized. Accumulating clinical and experimental evidence has emphasized the role of central autonomic network disorders and inflammation as key pathophysiological mechanisms of SHS. Therefore, an assessment of post-stroke cardiac dysautonomia is necessary. Currently, the development of treatment strategies for SHS is a vital but challenging task. Identifying potential key mediators and signaling pathways of SHS is essential for developing therapeutic targets. Therapies targeting pathophysiological mechanisms may be promising. Remote ischemic conditioning exerts protective effects through humoral, nerve, and immune-inflammatory regulatory mechanisms, potentially preventing the development of SHS. In the future, well-designed trials are required to verify its clinical efficacy. This comprehensive review provides valuable insights for future research.

[Acute ischemic stroke and troponin elevation: update of the Mannheim clinical algorithm]

Elevated high-sensitivity cardiac troponin (hs-cTn) levels should be expected in about half of all patients with acute ischemic stroke (AIS). Since those patients are at risk of increased morbidity and mortality, often attributable to cardiac causes, an adequate work-up of the underlying etiology is required. This can only be achieved by a team of cardiologists and neurologists. Since underlying causes of hs-cTn elevation in AIS patients are diverse, often atypical or silent in their clinical presentation and some, such as an accompanying myocardial infarction, can be acutely life-threatening, the work-up should follow a standardized clinical algorithm. The vast majority of hs-cTn elevations are caused by non-ischemic myocardial injury associated with AIS. This work presents a practice-oriented approach to differential diagnosis with the update of the Mannheim clinical algorithm for acute ischemic stroke and troponin elevation.

High-Sensitivity Cardiac Troponin T and Cardiovascular Risk After Ischemic Stroke or Transient Ischemic Attack

Background

High-sensitivity cardiac troponin T (hs-cTnT) is associated with cardiovascular disease (CVD) risk in general and various high-risk populations.

Objectives

The purpose of this study was to precisely characterize the association of hs-cTnT with CVD risk in patients following acute ischemic stroke or transient ischemic attack.

Methods

We conducted post hoc analyses of data from the STROKE-CARD trial (NCT02156778), a pragmatic randomized controlled trial of a disease management program in patients with acute ischemic stroke or transient ischemic attack (ABCD2 score ≥3). We measured hs-cTnT on admission (Roche Elecsys, detection limit 5 ng/L) and quantified HRs for a composite CVD outcome (ie, stroke, myocardial infarction, CVD death) adjusted for age, sex, prior coronary heart disease, prior heart failure, diabetes, smoking, systolic blood pressure, and low- and high-density-lipoprotein cholesterol.

Results

Among 1,687 patients (mean age, 69.3 ± 13.7 years; 40.7% female), hs-cTnT was detectable in 80.7%. Median hs-cTnT was 10 ng/L (IQR: 6-18 ng/L). Over a median follow-up of 12.1 months, 110 patients had a CVD event. The association of hs-cTnT level with CVD risk was of log-linear shape, with a multivariable-adjusted HR of 1.40 (95% CI: 1.15-1.70; P < 0.001) per 1-SD higher log-transformed hs-cTnT value. The strength of association was similar when further adjusted for other potential confounders and across clinically relevant subgroups. Corresponding outcome-specific HRs were 1.33 (95% CI: 1.06-1.68; P = 0.016) for stroke, 1.28 (95% CI: 0.69-2.37; P = 0.430) for myocardial infarction, 1.98 (95% CI: 1.43-2.73; P < 0.001) for CVD death, and 1.93 (95% CI: 1.54-2.41; P < 0.001) for all-cause death.

Conclusions

High hs-cTnT is associated with increased CVD risk in ischemic stroke and transient ischemic attack patients.

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.

High-Sensitivity Cardiac Troponin T and Cognitive Function Over 12 Months After Stroke-Results of the DEMDAS Study

BACKGROUND

Subclinical myocardial injury in form of hs-cTn (high-sensitivity cardiac troponin)  levels has been associated with cognitive impairment and imaging markers of cerebral small vessel disease (SVD) in population-based and cardiovascular cohorts. Whether hs-cTn is associated with domain-specific cognitive decline and SVD burden in patients with stroke remains unknown.

METHODS AND RESULTS

We analyzed patients with acute stroke without premorbid dementia from the prospective multicenter DEMDAS (DZNE [German Center for Neurodegenerative Disease]-Mechanisms of Dementia after Stroke) study. Patients underwent neuropsychological testing 6 and 12 months after the index event. Test results were classified into 5 cognitive domains (language, memory, executive function, attention, and visuospatial function). SVD markers (lacunes, cerebral microbleeds, white matter hyperintensities, and enlarged perivascular spaces) were assessed on cranial magnetic resonance imaging to constitute a global SVD score. We examined the association between hs-cTnT (hs-cTn T levels) and cognitive domains as well as the global SVD score and individual SVD markers, respectively. Measurement of cognitive and SVD-marker analyses were performed in 385 and 466 patients with available hs-cTnT levels, respectively. In analyses adjusted for demographic characteristics, cardiovascular risk factors, and cognitive status at baseline, higher hs-cTnT was negatively associated with the cognitive domains "attention" up to 12 months of follow-up (beta-coefficient, -0.273 [95% CI, -0.436 to -0.109]) and "executive function" after 12 months. Higher hs-cTnT was associated with the global SVD score (adjusted odds ratio, 1.95 [95% CI, 1.27-3.00]) and the white matter hyperintensities and lacune subscores.

CONCLUSIONS

In patients with stroke, hs-cTnT is associated with a higher burden of SVD markers and cognitive function in domains linked to vascular cognitive impairment.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01334749.

Sex Differences in Outcomes of Acute Myocardial Injury After Stroke

BACKGROUND

Sex differences in presentation, treatment, and prognosis of cardiovascular disorders are well recognized. Although an association between acute myocardial injury and mortality after ischemic stroke has been demonstrated, it is unclear whether prevalence and outcome of poststroke acute myocardial injury differ between women and men.

METHODS AND RESULTS

We prospectively screened consecutive patients with acute ischemic stroke and serial high-sensitivity cardiac troponin T measurements admitted to our center. Acute myocardial injury was defined as at least 1 high-sensitivity cardiac troponin T value above the upper reference limit (14 ng/L) with a rise/fall of >20%. Rates of acute myocardial injury were also calculated using sex-specific high-sensitivity cardiac troponin T cutoffs (women upper reference limit, 9 ng/L; men upper reference limit, 16 ng/L). Logistic regression analyses were performed to evaluate the association between acute myocardial injury and outcomes. Of 1067 patients included, 494 were women (46%). Women were older, had a higher rate of known atrial fibrillation, were more likely to be functionally dependent before admission, had higher stroke severity, and more often had cardioembolic strokes (all P values <0.05). The crude prevalence of acute myocardial injury differed by sex (29% women versus 23% men, P=0.024). Statistically significant associations between acute myocardial injury and outcomes were observed in women (7-day in-hospital mortality: adjusted odds ratio [aOR], 3.2 [95% CI, 1.07-9.3]; in-hospital mortality: aOR, 3.3 [95% CI, 1.4-7.6]; modified Rankin Scale score at discharge: aOR, 1.6 [95% CI, 1.1-2.4]) but not in men. The implementation of sex-specific cutoffs did not increase the prognostic value of acute myocardial injury for unfavorable outcomes.

CONCLUSIONS

The prevalence of acute myocardial injury after ischemic stroke and its association with mortality and greater disability might be sex-dependent.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03892226.

Clinical Interpretation of Serum Troponin in the Era of High-Sensitivity Testing

Cardiac troponin (Tn) plays a central role in the evaluation of patients with angina presenting with acute coronary syndrome. The advent of high-sensitivity assays has improved the analytic sensitivity and precision of serum Tn measurement, but this advancement has come at the cost of poorer specificity. The role of clinical judgment is of heightened importance because, more so than ever, the interpretation of serum Tn elevation hinges on the careful integration of findings from electrocardiographic, echocardiographic, physical exam, interview, and other imaging and laboratory data to formulate a weighted differential diagnosis. A thorough understanding of the epidemiology, mechanisms, and prognostic implications of Tn elevations in each cardiac and non-cardiac etiology allows the clinician to better distinguish between presentations of myocardial ischemia and myocardial injury-an important discernment to make, as the treatment of acute coronary syndrome is vastly different from the workup and management of myocardial injury and should be directed at the underlying cause.

Rising Cardiac Troponin: A Prognostic Biomarker for Mortality After Acute Ischemic Stroke

BACKGROUND

Elevated cardiac troponin (cTn) is detected in 10% to 30% of patients with acute ischemic stroke (AIS) and correlates with poor functional outcomes. Serial cTn measurements differentiate a dynamic cTn pattern (rise/fall >20%), specific for acute myocardial injury, from elevated but stable cTn levels (nondynamic), typically attributed to chronic cardiac/noncardiac conditions. We investigated if the direction of the cTn change (rising versus falling) affects mortality and outcome.

METHODS AND RESULTS

We retrospectively screened consecutive patients with AIS admitted to 5 stroke centers for elevated cTn at admission and at least 1 additional cTn measurement within 48 hours. The pattern of cTn was defined as rising if >20% increase from baseline, falling if >20% decrease, or nondynamic if ≤20% change in either direction. Logistic regression analyses were performed to assess the association of cTn patterns and 7-day mortality and unfavorable discharge disposition. Of 3789 patients with AIS screened, 300 were included. Seventy-two had a rising pattern, 66 falling, and 162 nondynamic. In patients with AIS with rising cTn, acute ischemic myocardial infarction was present in 54%, compared with 33% in those with falling cTn (P<0.01). Twenty-two percent of patients with a rising pattern had an isolated dynamic cTn in the absence of any ECG or echocardiogram changes, compared with 53% with falling cTn. A rising pattern was associated with higher risk of 7-day mortality (adjusted odds ratio [OR]=32 [95% CI, 2.5-415.0] rising versus aOR=1.3 [95% CI, 0.1-38.0] falling versus nondynamic as reference) and unfavorable discharge disposition (aOR=2.5 [95% CI, 1.2-5.2] rising versus aOR=0.6 [95% CI, 0.2-1.5] versus falling).

CONCLUSIONS

Rising cTn is independently associated with increased mortality and unfavorable discharge disposition in patients with AIS.

Interaction of heart failure and stroke: A clinical consensus statement of the ESC Council on Stroke, the Heart Failure Association (HFA) and the ESC Working Group on Thrombosis

Heart failure (HF) is a major disease in our society that often presents with multiple comorbidities with mutual interaction and aggravation. The comorbidity of HF and stroke is a high risk condition that requires particular attention to ensure early detection of complications, efficient diagnostic workup, close monitoring, and consequent treatment of the patient. The bi-directional interaction between the heart and the brain is inherent in the pathophysiology of HF where HF may be causal for acute cerebral injury, and - in turn - acute cerebral injury may induce or aggravate HF via imbalanced neural and neurovegetative control of cardiovascular regulation. The present document represents the consensus view of the ESC Council on Stroke, the Heart Failure Association and the ESC Working Group on Thrombosis to summarize current insights on pathophysiological interactions of the heart and the brain in the comorbidity of HF and stroke. Principal aspects of diagnostic workup, pathophysiological mechanisms, complications, clinical management in acute conditions and in long-term care of patients with the comorbidity are presented and state-of-the-art clinical management and current evidence from clinical trials is discussed. Beside the physicians perspective, also the patients values and preferences are taken into account. Interdisciplinary cooperation of cardiologists, stroke specialists, other specialists and primary care physicians is pivotal to ensure optimal treatment in acute events and in continued long-term treatment of these patients. Key consensus statements are presented in a concise overview on mechanistic insights, diagnostic workup, prevention and treatment to inform clinical acute and continued care of patients with the comorbidity of HF and stroke.

Stroke-Heart Syndrome: Does Sex Matter?

Background Cardiovascular complications after acute ischemic stroke (AIS) can be related to chronic/comorbid cardiac conditions or acute disruption of the brain-heart autonomic axis (stroke-heart syndrome). Women are known to be more vulnerable to certain stress-induced cardiac complications, such as Takotsubo cardiomyopathy. We investigated sex differences in cardiac troponin (cTn) elevation, cardiac events, and outcomes after AIS. Methods and Results We retrospectively analyzed consecutive patients with AIS from 5 stroke centers. Patients with AIS with elevated baseline cTn and at least 2 cTn measurements were included, while patients with acute comorbid conditions that could impact cTn levels were excluded. Poststroke acute myocardial injury was defined as the presence of a dynamic cTn pattern (rise/fall >20% in serial measurements) in the absence of acute atherosclerotic coronary disease (type 1 myocardial infarction) or cardiac death (type 3 myocardial infarction). From a total cohort of 3789 patients with AIS, 300 patients were included in the study: 160 were women (53%). Women were older, had a lower burden of cardiovascular risk factors, and more frequently had cardioembolic stroke and right insula involvement (P values all <0.05). In multivariate analysis, women were more likely to have a dynamic cTn pattern (adjusted odds ratio, 2.1 [95% CI, 1.2-3.6]) and develop poststroke acute myocardial injury (adjusted odds ratio, 2.1 [95% CI, 1.1-3.8]). Patients with poststroke acute myocardial injury had higher 7-day mortality (adjusted odds ratio, 5.5 [95% CI, 1.2-24.4]). Conclusions In patients with AIS with elevated cTn at baseline, women are twice as likely to develop poststroke acute myocardial injury, and this is associated with higher risk of short-term mortality. Translational studies are needed to clarify mechanisms underlying sex differences in cardiac events and mortality in AIS.

Immunological characterization of stroke-heart syndrome and identification of inflammatory therapeutic targets

Acute cardiac dysfunction caused by stroke-heart syndrome (SHS) is the second leading cause of stroke-related death. The inflammatory response plays a significant role in the pathophysiological process of cardiac damage. However, the mechanisms underlying the brain-heart interaction are poorly understood. Therefore, we aimed to analysis the immunological characterization and identify inflammation therapeutic targets of SHS. We analyzed gene expression data of heart tissue 24 hours after induction of ischemia stoke by MCAO or sham surgery in a publicly available dataset (GSE102558) from Gene Expression Omnibus (GEO). Bioinformatics analysis revealed 138 differentially expressed genes (DEGs) in myocardium of MCAO-treated compared with sham-treated mice, among which, immune and inflammatory pathways were enriched. Analysis of the immune cells infiltration showed that the natural killer cell populations were significantly different between the two groups. We identified five DIREGs, Aplnr, Ccrl2, Cdkn1a, Irak2, and Serpine1 and found that their expression correlated with specific populations of infiltrating immune cells in the cardiac tissue. RT-qPCR and Western blot methods confirmed significant changes in the expression levels of Aplnr, Cdkn1a, Irak2, and Serpine1 after MCAO, which may serve as therapeutic targets to prevent cardiovascular complications after stroke.

The Impact of Elevated Troponin Levels on Clinical Outcomes in Patients with Acute Ischemic Stroke: A Systematic Review

The association between high cardiac troponin (cTn) levels and stroke characteristics and outcomes remains unclear. This systematic review aimed to determine the prevalence and clinical implications of elevated cTn levels in patients with acute ischemic stroke (AIS). We conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) 2020 guidelines. A comprehensive search of PubMed, Google Scholar, Science Direct, and Research Gate databases was conducted to identify relevant studies published in English up to May 2023. This study included all reports on serum cTn levels and AIS. Two independent reviewers assessed study quality and bias using study-specific tools before inclusion. The systematic review included a total of 14 articles with 16906 participants, including one systematic review, one randomized controlled trial (RCT), and 12 observational studies. The results of this systematic review indicate that the prevalence of high cTn levels is averaged at 17.9%, or 1 in 5 individuals, who have an AIS. The review emphasizes the detrimental effects of increased cTn levels on outcomes for in-hospital and all-cause mortality as well as cardiovascular outcomes in patients with AIS. These results demonstrate that serum cTn has the potential to be a useful tool for risk classification and prognostic assessment in individuals with AIS. AIS patients with elevated serum cTn at baseline have an increased risk of mortality. Early and routine evaluation of serum cTn may contribute to the timely detection of co-morbid cardiovascular injury and prevent unfavorable outcomes in patients with AIS.

Cardiac dysfunction and high-sensitive C-reactive protein are associated with troponin T elevation in ischemic stroke: insights from the SICFAIL study

BACKGROUND

Troponin elevation is common in ischemic stroke (IS) patients. The pathomechanisms involved are incompletely understood and comprise coronary and non-coronary causes, e.g. autonomic dysfunction. We investigated determinants of troponin elevation in acute IS patients including markers of autonomic dysfunction, assessed by heart rate variability (HRV) time domain variables.

METHODS

Data were collected within the Stroke Induced Cardiac FAILure (SICFAIL) cohort study. IS patients admitted to the Department of Neurology, Würzburg University Hospital, underwent baseline investigation including cardiac history, physical examination, echocardiography, and blood sampling. Four HRV time domain variables were calculated in patients undergoing electrocardiographic Holter monitoring. Multivariable logistic regression with corresponding odds ratios (OR) and 95% confidence intervals (CI) was used to investigate the determinants of high-sensitive troponin T (hs-TnT) levels ≥14 ng/L.

RESULTS

We report results from 543 IS patients recruited between 01/2014-02/2017. Of those, 203 (37%) had hs-TnT ≥14 ng/L, which was independently associated with older age (OR per year 1.05; 95% CI 1.02-1.08), male sex (OR 2.65; 95% CI 1.54-4.58), decreasing estimated glomerular filtration rate (OR per 10 mL/min/1.73 m2 0.71; 95% CI 0.61-0.84), systolic dysfunction (OR 2.79; 95% CI 1.22-6.37), diastolic dysfunction (OR 2.29; 95% CI 1.29-4.02), atrial fibrillation (OR 2.30; 95% CI 1.25-4.23), and increasing levels of C-reactive protein (OR 1.48 per log unit; 95% CI 1.22-1.79). We did not identify an independent association of troponin elevation with the investigated HRV variables.

CONCLUSION

Cardiac dysfunction and elevated C-reactive protein, but not a reduced HRV as surrogate of autonomic dysfunction, were associated with increased hs-TnT levels in IS patients independent of established cardiovascular risk factors. Registration-URL: https://www.drks.de/drks_web/; Unique identifier: DRKS00011615.

Assessing electrocardiogram changes after ischemic stroke with artificial intelligence

OBJECTIVE

Ischemic stroke (IS) with subsequent cerebrocardiac syndrome (CCS) has a poor prognosis. We aimed to investigate electrocardiogram (ECG) changes after IS with artificial intelligence (AI).

METHODS

We collected ECGs from a healthy population and patients with IS, and then analyzed participant demographics and ECG parameters to identify abnormal features in post-IS ECGs. Next, we trained the convolutional neural network (CNN), random forest (RF) and support vector machine (SVM) models to automatically detect the changes in the ECGs; Additionally, We compared the CNN scores of good prognosis (mRS ≤ 2) and poor prognosis (mRS > 2) to assess the prognostic value of CNN model. Finally, we used gradient class activation map (Grad-CAM) to localize the key abnormalities.

RESULTS

Among the 3506 ECGs of the IS patients, 2764 ECGs (78.84%) led to an abnormal diagnosis. Then we divided ECGs in the primary cohort into three groups, normal ECGs (N-Ns), abnormal ECGs after the first ischemic stroke (A-ISs), and normal ECGs after the first ischemic stroke (N-ISs). Basic demographic and ECG parameter analyses showed that heart rate, QT interval, and P-R interval were significantly different between 673 N-ISs and 3546 N-Ns (p < 0.05). The CNN has the best performance among the three models in distinguishing A-ISs and N-Ns (AUC: 0.88, 95%CI = 0.86-0.90). The prediction scores of the A-ISs and N-ISs obtained from the all three models are statistically different from the N-Ns (p < 0.001). Futhermore, the CNN scores of the two groups (mRS > 2 and mRS ≤ 2) were significantly different (p < 0.05). Finally, Grad-CAM revealed that the V4 lead may harbor the highest probability of abnormality.

CONCLUSION

Our study showed that a high proportion of post-IS ECGs harbored abnormal changes. Our CNN model can systematically assess anomalies in and prognosticate post-IS ECGs.

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.

Advances in brain-heart syndrome: Attention to cardiac complications after ischemic stroke

Neurocardiology is an emerging field that studies the interaction between the brain and the heart, namely the effects of heart injury on the brain and the effects of brain damage on the heart. Acute ischemic stroke has long been known to induce heart damage. Most post-stroke deaths are attributed to nerve damage, and cardiac complications are the second leading cause of death after stroke. In clinical practice, the proper interpretation and optimal treatment for the patients with heart injury complicated by acute ischemic stroke, recently described as stroke-heart syndrome (SHS), are still unclear. Here, We describe a wide range of clinical features and potential mechanisms of cardiac complications after ischemic stroke. Autonomic dysfunction, microvascular dysfunction and coronary ischemia process are interdependent and play an important role in the process of cardiac complications caused by stroke. As a unique comprehensive view, SHS can provide theoretical basis for research and clinical diagnosis and treatment.

TRoponin of Unknown origin in STroke evaluated by multi-component cardiac Magnetic resonance Imaging – The TRUST-MI study

Aims

Increased high-sensitive cardiac troponin I (hs-cTnI) levels are common in patients with acute ischemic stroke. However, only a minority demonstrates culprit lesions on coronary angiography, suggesting other mechanisms, e.g., inflammation, as underlying cause of myocardial damage. Late Gadolinium Enhancement (LGE)-cardiac magnetic resonance (CMR) with mapping techniques [T1, T2, extracellular volume (ECV)] allow the detection of both focal and diffuse myocardial abnormalities. We investigated the prevalence of culprit lesions by coronary angiography and myocardial tissue abnormalities by a comprehensive CMR protocol in troponin-positive stroke patients.

Methods and results

Patients with troponin-positive acute ischemic stroke and no history of coronary artery disease were prospectively enrolled. Coronary angiography and CMR (LGE, T1 + T2 mapping, ECV) were performed within the first days of the acute stroke. Twenty-five troponin-positive patients (mean age 62 years, 44% females) were included. 2 patients (8%) had culprit lesions on coronary angiography and underwent percutaneous coronary intervention. 13 patients (52%) demonstrated LGE: (i) n = 4 ischemic, (ii) n = 4 non-ischemic, and (iii) n = 5 ischemic AND non-ischemic. In the 12 LGE-negative patients, mapping revealed diffuse myocardial damage in additional 9 (75%) patients, with a high prevalence of increased T2 values.

Conclusions

Our data show a low prevalence of culprit lesions in troponin-positive stroke patients. However, &gt; 50% of the patients demonstrated myocardial scars (ischemic + non-ischemic) by LGE-CMR. Mapping revealed additional myocardial abnormalities (mostly inflammatory) in the majority of LGE-negative patients. Therefore, a comprehensive CMR protocol gives important insights in the etiology of troponin which might have implications for the further work-up of troponin-positive stroke patients.

Stroke-Heart Syndrome: Recent Advances and Challenges

After ischemic stroke, there is a significant burden of cardiovascular complications, both in the acute and chronic phase. Severe adverse cardiac events occur in 10% to 20% of patients within the first few days after stroke and comprise a continuum of cardiac changes ranging from acute myocardial injury and coronary syndromes to heart failure or arrhythmia. Recently, the term stroke–heart syndrome was introduced to provide an integrated conceptual framework that summarizes neurocardiogenic mechanisms that lead to these cardiac events after stroke. New findings from experimental and clinical studies have further refined our understanding of the clinical manifestations, pathophysiology, and potential long‐term consequences of the stroke–heart syndrome. Local cerebral and systemic mediators, which mainly involve autonomic dysfunction and increased inflammation, may lead to altered cardiomyocyte metabolism, dysregulation of (tissue‐resident) leukocyte populations, and (micro‐) vascular changes. However, at the individual patient level, it remains challenging to differentiate between comorbid cardiovascular conditions and stroke‐induced heart injury. Therefore, further research activities led by joint teams of basic and clinical researchers with backgrounds in both cardiology and neurology are needed to identify the most relevant therapeutic targets that can be tested in clinical trials.

Prognostic Value of Serum Cardiac Troponin in Acute Ischemic Stroke: An Updated Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Cardiac troponin (cTn) is a specific biomarker of cardiac injury and elevation of cTn is related to increased mortality. However, prognostic value of cTn in patients with acute ischemic stroke (AIS) still remains to be elucidated. The aim of this review is to explore the strength of association between elevated cTn and mortality after AIS onset.

METHODS

PubMed, EMBASE, and Cochrane Library were searched from inception to July 12, 2021 without language restriction. All studies reporting the association between cTn on admission and mortality in AIS patients have been included in this review. Meta-analysis was performed for overall and pre-specified subgroup risk ratios (RR) were obtained using a random effect model. Study quality was assessed for each included study.

RESULTS

There were 20 studies included in this meta-analysis with 9779 AIS patients met the inclusion criteria. There was significant association between elevated cTn and mortality in patients with AIS (RR 3.87; 95% CI 3.24-4.63). The association was consistent across the pre-specified subgroup analyses by type of troponin (cTnT or cTnI), assay of troponin (conventional or high-sensitivity), region (Asian or Non-Asian), definite exclusion of ACS/AMI patients or not (yes or not mentioned), adjusted AF, HF and impaired renal function or not (yes or no).

CONCLUSIONS

AIS patients with elevated cTn at baseline has an increased risk of mortality. Early and routine evaluation of cTn may contribute to timely detection of comorbid cardiac injury and prevent unfavorable outcomes in patients with AIS.

PROSPERO REGISTRATION NUMBER

CRD42020160912.

Coronary Artery Disease in Patients Presenting With Acute Ischemic Stroke or Transient Ischemic Attack and Elevated Troponin Levels

Background: There is little information concerning the invasive coronary angiography (ICA) findings of patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA) with elevated troponin levels and suspected myocardial infarction (MI). This study analyzed patient characteristics associated with ICA outcomes.

Methods: A total of 8,322 patients with AIS or TIA, treated between March 2010 and May 2020, were retrospectively screened for elevated serum troponin I at hospital admission. Patients in whom ICA was performed, due to suspected type 1 MI based on symptoms, echocardiography, and ECG, were categorized according to ICA results (non-obstructive coronary artery disease (CAD): ≥1 stenosis ≥50% but no stenosis ≥80%; obstructive CAD: any stenosis ≥80% or hemodynamically relevant stenosis assessed by FFR/iwFR).

Results: Elevated troponin levels were detected in 2,205 (22.5%) patients, of whom 123 (5.6%) underwent ICA (mean age 71 ± 12 years; 67% male). CAD was present in 98 (80%) patients, of whom 51 (41%) were diagnosed with obstructive CAD. Thus, ICA findings of obstructive CAD accounted for 2.3% of patients with troponin elevation and 0.6% of all stroke patients. The clinical hallmarks of myocardial ischemia, including angina pectoris (31 vs. 15%, p < 0.05) and regional wall motion abnormalities (49 vs. 32%, p = 0.07), and increased cardiovascular risk indicated obstructive CAD. While there was no association between lesion site or stroke severity and ICA findings, causal large-artery atherosclerosis was significantly more common in patients with obstructive coronary disease (p < 0.05).

Conclusion: The rate of obstructive CAD in patients with stroke or TIA and elevated troponin levels with suspected concomitant type I MI is low. The cumulation of several cardiovascular risk factors and clinical signs of MI were predictive. AIS patients with large-artery atherosclerosis and elevated troponin may represent an especially vulnerable subgroup of stroke patients with risk for obstructive CAD.

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.

Evaluation of Transient Ischemic Attack and Minor Stroke: A Rapid Outpatient Model for the COVID-19 Pandemic and Beyond

The grim circumstances of the COVID-19 pandemic have highlighted the need to refine and adapt stroke systems of care. Patients' care-seeking behaviors have changed due to perceived risks of in-hospital treatment during the pandemic. In response to these challenges, we optimized a recently implemented, novel outpatient approach for the evaluation and management of minor stroke and transient ischemic attack, entitled RESCUE-TIA. This modified approach incorporated telemedicine visits and remote testing, and proved valuable during the pandemic. In this review article, we provide the evidence-based rationale for our approach, describe its operationalization, and provide data from our initial experience.

OUP accepted manuscript

The management of patients with stroke is often multidisciplinary, involving various specialties and healthcare professionals. Given the common shared risk factors for stroke and cardiovascular disease, input may also be required from the cardiovascular teams, as well as patient caregivers and next-of-kin. Ultimately, the patient is central to all this, requiring a coordinated and uniform approach to the priorities of post-stroke management, which can be consistently implemented by different multidisciplinary healthcare professionals, as part of the patient ‘journey’ or ‘patient pathway,’ supported by appropriate education and tele-medicine approaches. All these aspects would ultimately aid delivery of care and improve patient (and caregiver) engagement and empowerment. Given the need to address the multidisciplinary approach to holistic or integrated care of patients with heart disease and stroke, the European Society of Cardiology Council on Stroke convened a Task Force, with the remit to propose a consensus on Integrated care management for optimizing the management of stroke and associated heart disease. The present position paper summarizes the available evidence and proposes consensus statements that may help to define evidence gaps and simple practical approaches to assist in everyday clinical practice. A post-stroke ABC pathway is proposed, as a more holistic approach to integrated stroke care, would include three pillars of management:

A: Appropriate Antithrombotic therapy.

B: Better functional and psychological status.

C: Cardiovascular risk factors and Comorbidity optimization (including lifestyle changes).

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).

The Alberta Stroke Program Early CT score (ASPECTS): A predictor of mortality in acute ischemic stroke

Stroke is one of the leading causes of mortality globally and a main cause of disability. The objective of this study was to evaluate the importance and utility of the Alberta Stroke Program Early CT Score (ASPECTS) as a mortality predictor factor in diabetic vs. non-diabetic patients with acute ischemic stroke (AIS), correlated with age, monocyte values, and high-sensitivity cardiac troponin I (hs-cTnI). The prospective longitudinal observational study included 340 patients with AIS divided into two groups: diabetics and non-diabetics. ASPECTS was evaluated within the first 24 h after admission to the center. The ASPECTS was lower in the group of diabetic patients on average 4.9 vs. 6.05 (P<0.0001). As the age of the patients increased, the lower the ASPECTS and the higher infarct size, indicating a statistically significant (P<0.0001) result. The optimal correlation was observed between infarct size (ASPECTS) and hs-cTnI serum level [95% confidence interval (CI): -0.3216 to -0.1193; P<0.0001]. Almost 94% of patients who had an ASPECTS higher than 3 points on admission survived, resulting in a favorable outcome and a very good predictability of the score (95% CI: 0.85 to 0.926, P<0.0001). The ASPECTS is a mortality predictor, its value correlating inversely with the severity and evolution of patients, confirming a good predictability with good specificity, sensitivity and area under the curve.

Prognostic value of elevated high-sensitivity cardiac troponin T in acute ischemic stroke patients treated with endovascular thrombectomy in late time windows

OBJECTIVE

To evaluate the prognostic significance of high-sensitivity cardiac troponin T (hs-cTnT) elevation in acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) in the anterior circulation treated with endovascular thrombectomy (ET) in late time windows and identify the factors associated with hs-cTnT elevation.

METHODS

A total of 152 AIS patients treated with ET in late time windows between January 2018 and August 2020 were included in this study. Patients were stratified into either normal or elevated hs-cTnT groups according to a cutoff value of 14 ng/L on admission. Baseline demographic features, comorbidities, and imaging data were compared between the elevated hs-cTnT group (＞14 ng/L) and the normal hs-cTnT group (≤14 ng/L). After accounting for these clinical characteristics, the association between hs-cTnT elevation and clinical outcomes was evaluated.

RESULTS

69(45.4%) patients had elevated hs-cTnT levels (>14 ng/L) on admission. The multivariable logistic regression analysis demonstrated that hs-cTnT elevation was independently associated with 3-month all-cause mortality (P = 0.014, OR 3.907, 95% CI 1.313-11.625) and 3-month composite unfavorable outcome (mRS 3-6) (P = 0.001, OR 5.099, 95% CI 1.873-13.888). Old age (P = 0.002, OR 1.053, 95% CI 1.020-1.088), admission NIHSS score (P = 0.015, OR 1.057, 95% CI 1.011-1.106), congestive heart failure (P = 0.016, OR 4.341, 95% CI 1.322-14.257) and coronary artery disease (P = 0.020, OR 2.914, 95% CI 1.183-7.180) were independently associated with hs-cTnT elevation.

CONCLUSION

In AIS patients treated with ET in late time windows, elevated hs-cTnT is independently associated with an increased risk of 3-month poor outcomes. Old age, high admission NIHSS score, coronary artery disease, and congestive heart failure are independent predictors of hs-cTnT elevation.

Cardiac Troponin and Recurrent Major Vascular Events after Minor Stroke or Transient Ischemic Attack

OBJECTIVE

This study was undertaken to investigate whether high-sensitivity cardiac troponin T (hs-cTnT) is associated with major adverse cardiovascular events (MACE) in patients with minor stroke or transient ischemic attack (TIA), and whether this association differs after risk stratification based on the Age, Blood Pressure, Clinical Features, Duration of Symptoms, Diabetes (ABCD² ) score.

METHODS

INSPiRE-TMS was a randomized controlled trial allocating patients with minor stroke or TIA to an intensified support program or conventional care. In this post hoc analysis, participants were categorized using hs-cTnT levels (5th generation; Roche Diagnostics, Manheim, Germany; 99th percentile upper reference limit [URL] = 14ng/l). Vascular risk was stratified using the ABCD² score (lower risk = 0-5 vs higher risk = 6-7). Cox proportional hazard regression was performed using covariate adjustment and propensity score matching (PSM) for the association between hs-cTnT and MACE (stroke/nonfatal coronary event/vascular death).

RESULTS

Among 889 patients (mean age = 70 years, 37% female), MACE occurred in 153 patients (17.2%) during a mean follow-up of 3.2 years. hs-cTnT was associated with MACE (9.3%/yr, >URL vs 4.4%/yr, ≤URL, adjusted hazard ratio [HR] = 1.63 [95% confidence interval (CI) = 1.13-2.35], adjusted HR [Q₄ vs Q₁ ] = 2.57 [95% CI = 1.35-4.97], adjusted HR [log-transformed] = 2.31 [95% CI = 1.37-3.89]). This association remained after PSM (adjusted HR = 1.76 [95% CI = 1.14-2.72]). There was a significant interaction between hs-cTnT and ABCD² category for MACE occurrence (p_interaction  = 0.04). In the lower risk category, MACE rate was 9.5%/yr in patients with hs-cTnT > URL, which was higher than in those ≤URL (3.8%/yr) and similar to the overall rate in the higher risk category.

INTERPRETATION

hs-cTnT levels are associated with incident MACE within 3 years after minor stroke or TIA and may help to identify high-risk individuals otherwise deemed at lower risk based on the ABCD² score. If confirmed in independent validation studies, this might warrant intensified secondary prevention measures and cardiac diagnostics in stroke patients with elevated hs-cTnT. ANN NEUROL 2021;90:901-912.

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.

Role of troponin as a biomarker for predicting outcome after ischemic stroke

BACKGROUND:

After acute ischemic stroke, a higher level of troponin has been considered as an important biomarker for predicting mortality.

AIM AND OBJECTIVES:

The study aimed to quantitatively assess the prognostic significance of the effect of baseline troponin levels on all-cause mortality in patients with acute ischemic stroke using a meta-analysis approach.

MATERIALS AND METHODS:

The following electronic databases such as PubMed, Web of Science, Cochrane Central Register of Controlled Trials, TRIP Database, and ClinicalTrialsgov were used for obtaining the relevant articles from literature. Data were extracted in standardized data collection form by two independent investigators. Any disagreements were resolved by consensus. All the statistical analyses were performed in STATA software (Version 13.1).

RESULTS:

A total of 19 studies were included in the present meta-analysis involving a total of 10,519 patients. The pooled analysis suggested that elevated serum troponin level was associated with inhospital mortality (rate ratios [RR] 2.34, 95% confidence interval [CI] 1.30–3.38) and at the end of last follow-up mortality (RR 2.01; 95% CI 1.62–2.40). Sensitivity analysis by removing a single study by turns indicated that there was no obvious impact of any individual study on the pooled risk estimate. No significant publication bias was observed in the beg test (P = 0.39); however, significant publication bias was observed in the egger test (P = 0.046).

CONCLUSION:

Our findings indicated that a higher level of troponin might be an important prognostic biomarker for all cause in hospital and follow-up mortalities in patients with acute ischemic stroke. These study findings offer insight into further investigation in prospective studies to validate this particular association. The study was registered in OSF registries DOI's 10.17605/OSF. IO/D95GN

High-Sensitivity Cardiac Troponin T and Recurrent Vascular Events After First Ischemic Stroke

Background Recent evidence suggests cardiac troponin levels to be a marker of increased vascular risk. We aimed to assess whether levels of high-sensitivity cardiac troponin T (hs-cTnT) are associated with recurrent vascular events and death in patients with first-ever, mild to moderate ischemic stroke. Methods and Results We used data from the PROSCIS-B (Prospective Cohort With Incident Stroke Berlin) study. We computed Cox proportional hazards regression analyses to assess the association between hs-cTnT levels upon study entry (Roche Elecsys, upper reference limit, 14 ng/L) and the primary outcome (composite of recurrent stroke, myocardial infarction, and all-cause death). A total of 562 patients were analyzed (mean age, 67 years [SD 13]; 38.6% women; median National Institutes of Health Stroke Scale=2; hs-cTnT above upper reference limit, 39.2%). During a mean follow-up of 3 years, the primary outcome occurred in 89 patients (15.8%), including 40 (7.1%) recurrent strokes, 4 (0.7%) myocardial infarctions, and 51 (9.1%) events of all-cause death. The primary outcome occurred more often in patients with hs-cTnT above the upper reference limit (27.3% versus 10.2%; adjusted hazard ratio, 2.0; 95% CI, 1.3-3.3), with a dose-response relationship when the highest and lowest hs-cTnT quartiles were compared (15.2 versus 1.8 events per 100 person-years; adjusted hazard ratio, 4.8; 95% CI, 1.9-11.8). This association remained consistent in sensitivity analyses, which included age matching and stratification for sex. Conclusions Hs-cTnT is dose-dependently associated with an increased risk of recurrent vascular events and death within 3 years after first-ever, mild to moderate ischemic stroke. These findings support further studies of the utility of hs-cTnT for individualized risk stratification after stroke. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01363856.

Cardiovascular autonomic dysfunction after stroke

Strokes are the paradigmatic example of the sudden impairment of the cerebral regulation of cardiac autonomic regulation. Although several aspects of dysautonomic cardiovascular regulation post stroke remain unanswered, there has been a wealth of research in this area in the last decade. In this article, we present a state-of-the-art review on the anatomical and functional organization of cardiovascular autonomic regulation, and the pathophysiology, incidence, time course, diagnosis, clinical aspects, prognosis, and management of post-stroke cardiovascular autonomic dysfunction.

Post-Stroke Cardiovascular Complications and Neurogenic Cardiac Injury: JACC State-of-the-Art Review

Over 1.5 million deaths worldwide are caused by neurocardiogenic syndromes. Furthermore, the consequences of deleterious brain-heart interactions are not limited to fatal complications. Cardiac arrhythmias, heart failure, and nonfatal coronary syndromes are also common. The brain-heart axis is implicated in post-stroke cardiovascular complications known as the stroke-heart syndrome, sudden cardiac death, and Takotsubo syndrome, among other neurocardiogenic syndromes. Multiple pathophysiological mechanisms with the potential to be targeted with novel therapies have been identified in the last decade. In the present state-of-the-art review, we describe recent advances in the understanding of anatomical and functional aspects of the brain-heart axis, cardiovascular complications after stroke, and a comprehensive pathophysiological model of stroke-induced cardiac injury.

[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

The role of cardiologists on the stroke unit

Cardiologists need a better understanding of stroke and of cardiac implications in modern stroke management. Stroke is a leading disease in terms of mortality and disability in our society. Up to half of ischaemic strokes are directly related to cardiac and large artery diseases and cardiovascular risk factors are involved in most other strokes. Moreover, in an acute stroke direct central brain signals and a consecutive autonomic/vegetative imbalance may account for severe and life-threatening cardiovascular complications. The strong cerebro-cardiac link in acute stroke has recently been addressed as the stroke-heart syndrome that requires careful cardiovascular monitoring and immediate therapeutic measures. The regular involvement of cardiologic expertise in daily work on a stroke unit is therefore of high importance and a cornerstone of up-to-date comprehensive stroke care concepts. The main targets of the cardiologists' contribution to acute stroke care can be categorized in three main areas (i) diagnostics workup of stroke aetiology, (ii) treatment and prevention of complications, and (iii) secondary prevention and sub-acute workup of cardiovascular comorbidity. All three aspects are by themselves highly relevant to support optimal acute management and to improve the short-term and long-term outcomes of patients. In this article, an overview is provided on these main targets of cardiologists' contribution to acute stroke management.

High-Sensitivity Cardiac Troponin T for Risk Stratification in Patients With Embolic Stroke of Undetermined Source

Background and Purpose:

Optimal secondary prevention for patients with embolic stroke of undetermined source (ESUS) remains unknown. We aimed to assess whether high-sensitivity cardiac troponin T (hs-cTnT) levels are associated with major vascular events and whether hs-cTnT may identify patients who benefit from anticoagulation following ESUS.

Methods:

Data were obtained from the biomarker substudy of the NAVIGATE ESUS trial, a randomized controlled trial testing the efficacy of rivaroxaban versus aspirin for secondary stroke prevention in ESUS. Patients were dichotomized at the hs-cTnT upper reference limit (14 ng/L, Gen V, Roche Diagnostics). Cox proportional hazard models were computed to explore the association between hs-cTnT, the combined cardiovascular end point (recurrent stroke, myocardial infarction, systemic embolism, cardiovascular death), and recurrent ischemic stroke.

Results:

Among 1337 patients enrolled at 111 participating centers in 18 countries (mean age 67±9 years, 61% male), hs-cTnT was detectable in 95% and at/above the upper reference limit in 21%. During a median follow-up of 11 months, the combined cardiovascular end point occurred in 68 patients (5.0%/y, rivaroxaban 28 events, aspirin 40 events; hazard ratio, 0.67 [95% CI, 0.41–1.1]), and recurrent ischemic stroke occurred in 50 patients (4.0%/y, rivaroxaban 16 events, aspirin 34 events, hazard ratio 0.45 [95% CI, 0.25–0.81]). Annualized combined cardiovascular end point rates were 8.2% (9.5% rivaroxaban, 7.0% aspirin) for those above hs-cTnT upper reference limit and 4.8% (3.1% rivaroxaban, 6.6% aspirin) below with a significant treatment modification ( P =0.04). Annualized ischemic stroke rates were 4.7% above hs-cTnT upper reference limit and 3.9% below, with no suggestion of an interaction between hs-cTnT and treatment ( P =0.3).

Conclusions:

In patients with ESUS, hs-cTnT was associated with increased cardiovascular event rates. While fewer recurrent strokes occurred in patients receiving rivaroxaban, outcomes were not stratified by hs-cTn results. Our findings support using hs-cTnT for cardiovascular risk stratification but not for decision-making regarding anticoagulation therapy in patients with ESUS.

Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT02313909.

[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.

Neuro-arrhythmology: a challenging field of action and research: a review from the Task Force of Neuro-arrhythmology of Italian Association of Arrhythmias and Cardiac Pacing

: There is a growing interest in the study of the mechanisms of heart and brain interactions with the aim to improve the management of high-impact cardiac rhythm disorders, first of all atrial fibrillation. However, there are several topics to which the scientific interests of cardiologists and neurologists converge constituting the basis for enhancing the development of neuro-arrhythmology. This multidisciplinary field should cover a wide spectrum of diseases, even beyond the classical framework corresponding to stroke and atrial fibrillation and include the complex issues of seizures as well as loss of consciousness and syncope. The implications of a more focused interaction between neurologists and cardiologists in the field of neuro-arrhythmology should include in perspective the institution of research networks specifically devoted to investigate 'from bench to bedside' the complex pathophysiological links of the abovementioned diseases, with involvement of scientists in the field of biochemistry, genetics, molecular medicine, physiology, pathology and bioengineering. An investment in the field could have important implications in the perspectives of a more personalized approach to patients and diseases, in the context of 'precision'medicine. Large datasets and electronic medical records, with the approach typical of 'big data' could enhance the possibility of new findings with potentially important clinical implications. Finally, the interaction between neurologists and cardiologists involved in arrythmia management should have some organizational implications, with new models of healthcare delivery based on multidisciplinary assistance, similarly to that applied in the case of syncope units.

Association of Baseline Cardiac Troponin With Acute Myocardial Infarction in Stroke Patients Presenting Within 4.5 Hours

Background and Purpose- American Heart Association guidelines recommend obtaining baseline troponin in all patients with acute ischemic stroke. Yet, there is a paucity of data on the prevalence of baseline troponin elevation and specifically its diagnostic yield for acute myocardial infarction (AMI) in patients presenting within the time window for thrombolysis. Methods- We retrospectively analyzed 1072 consecutive patients admitted for acute ischemic stroke or transient ischemic attack, who presented within 4.5 hours of last known well (LKW). Patients who had baseline cardiac troponin I (bcTnI) obtained within 72 hours from LKW (n=525) were included in the study. Multivariable logistic regression was conducted to determine factors independently related to an elevated bcTnI (>0.04 ng/mL). We calculated the area under receiver operator curves, sensitivity, and specificity, to determine the diagnostic accuracy of (i) the bcTnI for AMI stratified by the time to assessment and (ii) the best time cutoff for obtaining bcTnI. Results- Among included subjects, the median time from LKW to the bcTnI was 3.8 hours and 113 (21.5%) subjects had an elevated bcTnI. Assessment of bcTnI within 4.5 hours from LKW was significantly more often associated with normal values as compared to assessment between 4.5 and 72 hours (61.7% versus 38.3%; P=0.001). Fifteen (2.9%) patients were diagnosed with AMI. After adjustment for pertinent confounders, time to bcTnI assessment was independently associated with AMI (odds ratio, 1.04 [95% CI, 1.02-1.07] P=0.001). When stratified by time, bcTnI assessed within 4.5 hours had a sensitivity of 25% and specificity of 83.7% for AMI, whereas bcTnI assessment between 4.5 and 72 hours was associated with a sensitivity of 90.9% and specificity of 74.8%. Conclusions- Assessment of bcTnI after 4.5 hours from LKW was associated with greater diagnostic accuracy than testing within 4.5 hours. This information may inform routine clinical practice.

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.

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.

Association Between Troponin Levels and Visceral Infarction in Patients with Acute Ischemic Stroke

BACKGROUND

Visceral infarctions appear to be more common in patients with embolic stroke subtypes, but their relation to troponin elevation remains uncertain.

METHODS

Among patients with acute ischemic stroke enrolled in the Cornell AcutE Stroke Academic Registry (CAESAR) from 2011 to 2016, we included those with troponin measured within 24 hours from stroke onset and a contrast-enhanced abdominal computed tomographic scan within 1 year of admission. A troponin elevation was defined as a value exceeding our laboratory's upper limit of normal (.04 ng/ mL) in the absence of a clinically recognized acute ST-segment elevation myocardial infarction. Visceral infarction was defined as a renal or splenic infarction as ascertained by a single radiologist blinded to patients' other characteristics. Multivariable logistic regression was used to evaluate the association between elevated troponin and visceral infarction.

RESULTS

Among 2116 patients registered in CAESAR from 2011 to 2016, 153 patients had both a troponin assay and a contrast-enhanced abdominal computed tomographic scan, of whom 33 (21%) had an elevated troponin and 22 (14%) had a visceral infarction. The prevalence of visceral infarction was higher among patients with an elevated troponin (30%; 95% confidence interval [CI], 16%-49%) than among patients without an elevated troponin (10%; 95% CI, 5%-17%) (P = .003). After adjustment for demographics and comorbidities, we found a significant association between elevated troponin and visceral infarction (odds ratio, 3.9; 95% CI, 1.5-10.4).

CONCLUSIONS

Among patients with acute ischemic stroke, elevated troponin was associated with visceral infarction. Our results demonstrate that poststroke troponin elevation may indicate the presence of underlying embolic sources.

[Cardiac involvement in neurological diseases]

Not only can cardiac diseases have neurological sequelae, but neurological diseases can also affect the heart. In this paper, the effects of a primary neurological disease on the heart are reviewed. Rare genetic muscular disorders, systemic neurodegenerative diseases, special neurological syndromes and sequelae of brain disease are discussed. A case vignette is used to illustrate that an undiagnosed neurological disease can trigger cardiac disease. Brain imaging should therefore always be considered in cardiac disease.

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.

The Confounding Effects of Non-cardiac Pathologies on the Interpretation of Cardiac Biomarkers

PURPOSE OF REVIEW

Cardiac biomarkers play important roles in routine evaluation of cardiac patients. But while these biomarkers can be extremely valuable, none of them should ever be used by themselves-without adding the clinical context. This paper explores the non-cardiac pathologies that can be seen with the cardiac biomarkers most commonly used.

RECENT FINDINGS

High-sensitivity troponin assay gained FDA approval for use in the USA, and studies demonstrated its diagnostic utility can be extended to patients with renal impairment. Gender-specific cut points may be utilized for high-sensitivity troponin assays. In the realm of the natriuretic peptides, studies demonstrated states of natriuretic peptide deficiency in obesity and in subjects of African-American race. Regardless, BNP and NT-proBNP both retained prognostic utilities across a variety of comorbid conditions. We are rapidly gaining clinical evidence with use of soluble ST2 and procalcitonin levels in management of cardiac disease states. In order to get the most utility from their measurement, one must be aware of non-cardiac pathologies that may affect the levels of biomarkers as although many of these are actually true values, they may not represent the disease we are trying to delineate. A few take-home points are as follows: 1. A biomarker value should never be used without clinical context 2. Serial sampling of biomarkers is often helpful 3. Panels of biomarkers may be valuable.