Myocardial Injury in the Era of High-Sensitivity Cardiac Troponin Assays: A Practical Approach for Clinicians

Role of Antitroponin Antibodies and Macrotroponin in the Clinical Interpretation of Cardiac Troponin

Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic value for cardiac diseases. However, heterophile antibodies, antitroponin antibodies, and macrotroponin complexes can be observed both in seemingly healthy individuals and patients with cardiac diseases, potentially leading to false positive or disproportionate elevation of cTn (cardiac troponin) assay results and introducing discrepancies in clinical interpretations with impact on medical management. In this review article, we describe the possible mechanisms of cTn release and the sources of variations in the assessment of circulating cTn levels. We also explore the pathophysiological mechanisms underlying antitroponin antibody development and discuss the influence exerted by macrotroponin complexes on the results of immunoassays. Additionally, we explore approaches to detect these complexes by presenting various clinical scenarios encountered in routine clinical practice. Finally, unsolved questions about the development, prevalence, and clinical significance of cardiac autoantibodies are discussed.

Myocardial injury in dogs: a retrospective analysis on etiological, echocardiographic, electrocardiographic, therapeutic, and outcome findings in 102 cases

INTRODUCTION

In dogs, myocardial injury (MI) is a poorly characterized clinical entity; therefore, this study aimed to provide a detailed description of dogs affected by this condition.

ANIMALS, MATERIALS, AND METHODS

Dogs diagnosed with MI according to the concentration of cardiac troponin I (cTnI) were retrospectively searched. Signalment, diagnostic, therapeutic, and outcome data were retrieved. Dogs were divided into six echocardiographic (dilated cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype with systolic dysfunction; abnormal echogenicity only; endocarditis; and no echocardiographic abnormalities suggestive of MI), four electrocardiographic (abnormalities of impulse formation; abnormalities of impulse conduction; abnormalities of ventricular repolarization; and no electrocardiographic abnormalities suggestive of MI), and nine etiological (infective; inflammatory; neoplastic; metabolic; toxic; nutritional; immune-mediated; traumatic/mechanical; and unknown) categories. Statistical analysis was performed to compare cTnI values among different categories and analyze survival.

RESULTS

One hundred two dogs were included. The median cTnI value was 3.71 ng/mL (0.2-180 ng/mL). Echocardiographic and electrocardiographic abnormalities were documented in 86 of 102 and 89 of 102 dogs, respectively. Among echocardiographic and electrocardiographic categories, the dilated cardiomyopathy phenotype (n = 52) and abnormalities of impulse formation (n = 67) were overrepresented, respectively. Among dogs in which a suspected etiological trigger was identified (68/102), the infective category was overrepresented (n = 20). Among dogs belonging to different echocardiographic, electrocardiographic, and etiological categories, cTnI did not differ significantly. The median survival time was 603 days; only eight of 102 dogs died due to MI.

CONCLUSIONS

Dogs with MI often have an identifiable suspected trigger, show various echocardiographic and electrocardiographic abnormalities, and frequently survive to MI-related complications.

Characteristics and outcomes of patients with symptomatic chronic myocardial injury in a Tanzanian emergency department: A prospective observational study

BACKGROUND

Chronic myocardial injury is a condition defined by stably elevated cardiac biomarkers without acute myocardial ischemia. Although studies from high-income countries have reported that chronic myocardial injury predicts adverse prognosis, there are no published data about the condition in sub-Saharan Africa.

METHODS

Between November 2020 and January 2023, adult patients with chest pain or shortness of breath were recruited from an emergency department in Moshi, Tanzania. Medical history and point-of-care troponin T (cTnT) assays were obtained from participants; those whose initial and three-hour repeat cTnT values were abnormally elevated but within 11% of each other were defined as having chronic myocardial injury. Mortality was assessed thirty days following enrollment.

RESULTS

Of 568 enrolled participants, 81 (14.3%) had chronic myocardial injury, 73 (12.9%) had acute myocardial injury, and 412 (72.5%) had undetectable cTnT values. Of participants with chronic myocardial injury, the mean (± sd) age was 61.5 (± 17.2) years, and the most common comorbidities were CKD (n = 65, 80%) and hypertension (n = 60, 74%). After adjusting for CKD, thirty-day mortality rates (38% vs. 36%, aOR 1.03, 95% CI: 0.52-2.03, p = 0.931) were similar between participants with chronic myocardial injury and those with acute myocardial injury, but significantly greater (38% vs. 13.6%, aOR 3.63, 95% CI: 1.98-6.65, p<0.001) among participants with chronic myocardial injury than those with undetectable cTnT values.

CONCLUSION

In Tanzania, chronic myocardial injury is a poor prognostic indicator associated with high risk of short-term mortality. Clinicians practicing in this region should triage patients with stably elevated cTn levels in light of their increased risk.

Trajectory of cardiac troponin T following moderate-to-severe COVID-19 and the association with cardiac abnormalities

BACKGROUND

COVID-19 has been associated with cardiac troponin T (cTnT) elevations and changes in cardiac structure and function, but the link between cardiac dysfunction and high-sensitive cardiac troponin T (hs-cTnT) in the acute and convalescent phase is unclear.

OBJECTIVE

To assess whether hs-cTnT concentrations are associated with cardiac dysfunction and structural abnormalities after hospitalization for COVID-19, and to evaluate the performance of hs-cTnT to rule out cardiac pathology.

METHODS

Patients hospitalized with COVID-19 had hs-cTnT measured during the index hospitalization and after 3-and 12 months, when they also underwent an echocardiographic study. A subset also underwent cardiovascular magnetic resonance imaging (CMR) after 6 months. Cardiac abnormalities were defined as left ventricular hypertrophy or dysfunction, right ventricular dysfunction, or CMR late gadolinium.

RESULTS

We included 189 patients with hs-cTnT concentrations measured during hospitalization for COVID-19, and after 3-and 12 months: Geometric mean (95%CI) 13 (11-15) ng/L, 7 (6-8) ng/L and 7 (6-8) ng/L, respectively. Cardiac abnormalities after 3 months were present in 45 (30%) and 3 (8%) of patients with hs-cTnT ≥ and < 5 ng/L at 3 months, respectively (negative predictive value 92.3% [95%CI 88.5-96.1%]). The performance was similar in patients with and without dyspnea. Hs-cTnT decreased from hospitalization to 3 months (more pronounced in intensive care unit-treated patients) and remained unchanged from 3 to 12 months, regardless of the presence of cardiac abnormalities.

CONCLUSION

Higher hs-cTnT concentrations in the convalescent phase of COVID-19 are associated with the presence of cardiac pathology and low concentrations (< 5 ng/L) may support in ruling out cardiac pathology following the infection.

Serum Troponin I Assessments in 5- to 30-Year-Olds After BNT162b2 Vaccination

INTRODUCTION

Rare myocarditis and pericarditis cases have occurred in coronavirus disease 2019 (COVID-19) messenger RNA (mRNA) vaccine recipients. Troponin levels, a potential marker of myocardial injury, were assessed in healthy participants before and after BNT162b2 vaccination.

METHODS

Vaccine-experienced 12- to 30-year-olds in phase 3 crossover C4591031 Substudy B (NCT04955626) who had two or three prior BNT162b2 30-μg doses were randomized to receive BNT162b2 30 μg followed by placebo, or placebo followed by BNT162b2 30 µg, 1 month apart. A participant subset, previously unvaccinated against COVID-19, in the phase 3 C4591007 study (NCT04816643) received up to three vaccinations (BNT162b2 10 μg or placebo [5- to 11-year-olds]) or open-label BNT162b2 30 μg (12- to 15-year-olds). Blood samples collected pre-vaccination, 4 days post-vaccination, and 1-month post-vaccination (C4591031 Substudy B only) were analyzed. Frequencies of elevated troponin I levels (male, > 35 ng/l; female, > 17 ng/l) were assessed.

RESULTS

Percentages of 12- to 30-year-olds (n = 1485) in C4591031 Substudy B with elevated troponin levels following BNT162b2 or placebo receipt were 0.5% and 0.8% before vaccination, 0.7% and 1.0% at day 4, and 0.7% and 0.5% at 1 month, respectively. In Study C4591007 (n = 1265), elevated troponin I levels were observed in 0.2, 0.4, and 0.2% of 5- to 11-year-old BNT162b2 recipients at baseline and 4 days post-dose 2 and 3, respectively; corresponding values in 12- to 15-year-olds were 0.4, 0.4, and 0.7%. No 5- to 11-year-old placebo recipients had elevated troponin levels. No myocarditis or pericarditis cases or deaths were reported.

CONCLUSIONS

Among 5- to  < 30-year-olds in both studies, troponin levels were rarely elevated (≤ 1.0%) and similar before and post-vaccination; troponin levels were also similar between BNT162b2 and placebo in 12- to 30-year-old and 5- to 11-year-old recipients in the respective studies. No myocarditis or pericarditis cases were reported. These findings did not provide evidence that BNT162b2 causes troponin elevations. No utility of routine measurement of troponin levels in asymptomatic BNT162b2 recipients was identified.

Four high sensitivity troponin assays and mortality in US adults with cardiovascular disease: The national health and nutrition examination survey, 1999-2004

Objective

High sensitivity cardiac troponin (hs-cTn) may be useful to monitor residual risk in secondary prevention. Our objective was to study the correlations and comparative associations with mortality of four hs-cTn assays in US adults with known cardiovascular disease (CVD).

Methods

We studied 1,211 adults with a history of CVD who participated in the National Health and Nutrition Examination Survey (NHANES) 1999-2004. Using stored samples, we measured hs-cTnT (Roche) and three hs-cTnI assays (Abbott, Siemens, and Ortho). Outcomes were all-cause and CVD mortality, with follow-up through December 31, 2019.

Results

Mean age was 64 years, 48 % were female, and 80 % identified as non-Hispanic White. Pearson's correlation coefficients between hs-cTn assays ranged from 0.67 to 0.85. There were 848 deaths (365 from CVD). Among adults with a history of prior non-fatal CVD, each hs-cTn assay (log-transformed, per 1-SD) was independently associated with CVD death (HRs ranging from 1.55 to 2.16 per 1-SD, all p-values <0.05) and with all-cause death (HRs ranging from 1.31 to 1.62 per 1-SD, all p-values <0.05). Associations of hs-cTnT and all-cause and CVD death remained significant after adjusting for hs-cTnI (and vice versa). Associations between hs-cTnI and CVD death remained significant after mutually adjusting for other individual hs-cTnI assays: e.g., HR 2.21 (95 % CI 1.60, 3.05) for Ortho (hs-cTnI) after adjustment for Siemens (hs-cTnI) and HR 1.81 (95 % CI 1.35, 2.43) for Ortho (hs-cTnI) after adjustment for Abbott (hs-cTnI).

Conclusion

In US adults with a history of CVD, we found modest correlations between 4 hs-cTn assays. All assays were associated with all-cause and CVD mortality. The hs-cTnT assay was associated with mortality independent of the hs-cTnI assays. Hs-cTnI assays also appeared to be independent of each other. Thus, hs-cTn assays may provide distinct information for residual risk in secondary prevention adults.

Relationship between high sensitivity troponin I and clinical outcomes in non-acute coronary syndrome (non-ACS) acute heart failure patients - a one-year follow-up study

OBJECTIVE

The primary objective of the study was to investigate the correlation between high-sensitivity troponin I (hsTropI) levels during hospitalization and the prognostic outcome in patients with non-acute coronary syndrome (non-ACS) acute heart failure, over a follow-up period of one year. The secondary objective was to assess and characterize acute heart failure during index hospitalization.

METHODS

High sensitivity troponin I value was noted both at the time of admission and discharge. The correlation of admission hsTropI along with other parameters and risk factors with in-hospital mortality was studied. Patients of index hospitalization after discharge were followed up for one year and the composite endpoint of cardiovascular death or re-hospitalization for heart failure was noted. The correlation between admission and discharge hsTropI values with the composite endpoint was then analyzed.

RESULTS

Out of 350 patients, 38 (10.8 %) patients died during index hospitalization while 142 patients (46 %) developed composite outcomes during follow-up. Age, previous history of heart failure, atrial fibrillation, low left ventricular ejection fraction, systolic blood pressure, and high values of hsTropI above 99th percentiles were independent in-hospital mortality predictors. The value of hsTropI at the time of admission was not associated with poor composite outcome during follow-up. However, patients who showed an increasing trend of hsTropI value at the time of discharge were found to have a significant increase in the composite outcome.

CONCLUSION

High-sensitivity troponin I is a valuable biomarker that can predict in-hospital mortality and long-term follow-up outcomes in patients with acute heart failure. It plays a crucial role in developing improved strategies for heart failure surveillance and management in the community.

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.

Data-Independent Acquisition Proteomics and N-Terminomics Methods Reveal Alterations in Mitochondrial Function and Metabolism in Ischemic-Reperfused Hearts

Myocardial ischemia-reperfusion (IR) (stunning) injury triggers changes in the proteome and degradome of the heart. Here, we utilize quantitative proteomics and comprehensive degradomics to investigate the molecular mechanisms of IR injury in isolated rat hearts. The control group underwent aerobic perfusion, while the IR injury group underwent 20 min of ischemia and 30 min of reperfusion to induce a stunning injury. As MMP-2 activation has been shown to contribute to myocardial injury, hearts also underwent IR injury with ARP-100, an MMP-2-preferring inhibitor, to dissect the contribution of MMP-2 to IR injury. Using data-independent acquisition (DIA) and mass spectroscopy, we quantified 4468 proteins in ventricular extracts, whereby 447 proteins showed significant alterations among the three groups. We then used subtiligase-mediated N-terminomic labeling to identify more than a hundred specific cleavage sites. Among these protease substrates, 15 were identified following IR injury. We identified alterations in numerous proteins involved in mitochondrial function and metabolism following IR injury. Our findings provide valuable insights into the biochemical mechanisms of myocardial IR injury, suggesting alterations in reactive oxygen/nitrogen species handling and generation, fatty acid metabolism, mitochondrial function and metabolism, and cardiomyocyte contraction.

High-Sensitivity Cardiac Troponin Assays: Ready for Prime Time!

Rapid and accurate triage of patients presenting with chest pain to an emergency department (ED) is critical to prevent ED overcrowding and unnecessary resource use in individuals at low risk of acute myocardial infarction (AMI) and to efficiently and effectively guide patients at high risk to definite therapy. The use of biomarkers for rule-out or rule-in of suspected AMI has evolved substantially over the last several decades. Previously well-established biomarkers have been replaced by cardiac troponin (cTn). High-sensitivity cTn (hs-cTn) assays represent the newest generation of cTn assays and offer tremendous advantages, including improved sensitivity and precision. Still, implementation of these assays in the United States lags behind several other areas of the world. Within this educational review, we discuss the evolution of biomarker testing for detection of myocardial injury, address the specifics of hs-cTn assays and their recommended use within triage algorithms, and highlight potential challenges in their use. Ultimately, we focus on implementation strategies for hs-cTn assays, as they are now clearly ready for prime time.

Sex-related differences in non-ischemic myocardial injury in the emergency department: A real-world perspective

BACKGROUND

Myocardial injury is associated with adverse outcomes. No data are reported about sex differences in incidence and factors associated with myocardial injury in an emergency department (ED) setting from a real-world perspective. We aimed to assess whether sex plays a major role in the diagnosis of myocardial injury in the ED.

METHODS

In this subanalysis of a retrospective study, patients presenting at the ED with at least one high-sensitivity cardiac troponin T (hs-cTnT) value and without acute coronary syndromes diagnosis were compared.

RESULTS

31,383 patients were admitted to the ED, 4660 had one hs-cTnT value, and 3937 were enrolled: 1943 females (49.4%) and 1994 males (50.6%). The diagnosis of myocardial injury was higher among men (36.8% vs. 32.9%, p < 0.01). Male sex was independently associated with myocardial injury. An older age, an elevated NT-proB-type Natriuretic Peptide and a lower estimated glomerular filtrate rate were independently associated with myocardial injury in both sexes.

CONCLUSIONS

In the ED, from a real-world perspective, myocardial injury occurred more frequently in males, and it was associated with older age and the presence of cardiac, lung, and kidney disease but not higher hs-cTnT values.

Guidance for clinical practice using emergency and point-of-care ultrasonography

Owing to the miniaturization of diagnostic ultrasound scanners and their spread of their bedside use, ultrasonography has been actively utilized in emergency situations. Ultrasonography performed by medical personnel with focused approaches at the bedside for clinical decision-making and improving the quality of invasive procedures is now called point-of-care ultrasonography (POCUS). The concept of POCUS has spread worldwide; however, in Japan, formal clinical guidance concerning POCUS is lacking, except for the application of focused assessment with sonography for trauma (FAST) and ultrasound-guided central venous cannulation. The Committee for the Promotion of POCUS in the Japanese Association for Acute Medicine (JAAM) has often discussed improving the quality of acute care using POCUS, and the "Clinical Guidance for Emergency and Point-of-Care Ultrasonography" was finally established with the endorsement of JAAM. The background, targets for acute care physicians, rationale based on published articles, and integrated application were mentioned in this guidance. The core points include the fundamental principles of ultrasound, airway, chest, cardiac, abdominal, and deep venous ultrasound, ultrasound-guided procedures, and the usage of ultrasound based on symptoms. Additional points, which are currently being considered as potential core points in the future, have also been widely mentioned. This guidance describes the overview and future direction of ultrasonography for acute care physicians and can be utilized for emergency ultrasound education. We hope this guidance will contribute to the effective use of ultrasonography in acute care settings in Japan.

Characterization of Myocardial Injury With High-Sensitivity Troponin

BACKGROUND

High-sensitivity troponin I, cardiac form (hs-cTnI) accelerates the assessment of acute coronary syndrome. Little has been documented about its performance, how it relates to different types of myocardial injury, and its impact on morbidity and mortality. This study sought to expand understanding of hs-cTnI by characterizing types of myocardial injury, the impact of comorbidities, and 30-day outcomes.

METHODS

The study retrospectively evaluated 1,975 patients with hs-cTnI levels obtained in the emergency department or inpatient setting from June to September 2020. Troponin was considered elevated if it was higher than the 99th percentile for either sex. Charts were reviewed to determine the presence of myocardial injury. Troponin elevation was adjusted for demographics, comorbidities, and kidney dysfunction. Thirty-day mortality and readmission rates were calculated.

RESULTS

Of 1,975 patients, 468 (24%) had elevated hs-cTnI, and 330 (17%) had at least 1 type of myocardial injury, type 2 myocardial infarction being the most frequent. Sensitivity and specificity using the 99th percentile as a cutoff were 99% and 92%, respectively. The average maximum hs-cTnI level was significantly higher for type 1 myocardial infarction (P < .001). Being male, Black, non-Hispanic, and a hospital inpatient were all associated with higher initial and peak hs-cTnI levels (P < .001). Elevated hs-cTnI level, age, heart disease, kidney dysfunction, and inpatient status were predictive of 30-day mortality on multivariate analysis.

CONCLUSION

Elevated hs-cTnI levels in emergency department and inpatient settings occurs most commonly because of type 2 myocardial infarction. Maximum hs-cTnI level is associated with the patient's particular type of myocardial injury, certain demographics, and cardiovascular comorbidities, and it may be a predictor of 30-day outcomes.

Impact of acute kidney injury on major adverse cardiovascular events in intensive care survivors

Background

Acute kidney injury commonly occurs in patients admitted to ICU. After acute kidney injury, kidney function may not completely recover leading to increased risk of future cardiovascular events. We sought to ascertain the rates of cardiovascular events in ICU survivors and if these rates were affected by the presence of acute kidney injury whilst in ICU.

Methods

This retrospective observational cohort study utilised routinely collected data to identify patients who had survived an admission to one of two ICUs between July 2015 and June 2018. Baseline serum creatinine and subsequent values were used to identify acute kidney injury. Major adverse cardiovascular events described were myocardial injury, coronary artery intervention, or radiological evidence of stroke.

Results

Of the 3994 ICU survivors, major adverse cardiovascular events were identified in 385 patients (9.6%; 95% confidence interval [CI] 8.8-10.6%). Presence of acute kidney injury whilst in ICU was significantly associated with future major adverse cardiovascular events (hazard ratio=1.38; 95% CI 1.12-1.70; P-value=0.003) and future biochemical myocardial injury (hazard ratio=1.48; 95% CI 1.16-1.89; P-value=0.001). Acute kidney injury did not have a statistically significant association with future coronary artery interventions or future cerebrovascular events.

Conclusions

One in 10 ICU survivors experiences a major adverse cardiovascular event after discharge. Acute kidney injury whilst in ICU was associated with an increased risk of major adverse cardiovascular events and specifically myocardial injury. Further research is warranted on whether ICU survivors with acute kidney injury merit enhanced strategies for cardiovascular protection.

Antithrombotic Therapy in Arterial Thrombosis and Thromboembolism in COVID-19: An American College of Chest Physicians Expert Panel Report

BACKGROUND

Evidence increasingly shows that the risk of thrombotic complications in COVID-19 is associated with a hypercoagulable state. Several organizations have released guidelines for the management of COVID-19-related coagulopathy and prevention of VTE. However, an urgent need exists for practical guidance on the management of arterial thrombosis and thromboembolism in this setting.

RESEARCH QUESTION

What is the current available evidence informing the prevention and management of arterial thrombosis and thromboembolism in patients with COVID-19?

STUDY DESIGN AND METHODS

A group of approved panelists developed key clinical questions by using the Population, Intervention, Comparator, and Outcome (PICO) format that address urgent clinical questions regarding prevention and management of arterial thrombosis and thromboembolism in patients with COVID-19. Using MEDLINE via PubMed, a literature search was conducted and references were screened for inclusion. Data from included studies were summarized and reviewed by the panel. Consensus for the direction and strength of recommendations was achieved using a modified Delphi survey.

RESULTS

The review and analysis of the literature based on 11 PICO questions resulted in 11 recommendations. Overall, a low quality of evidence specific to the population with COVID-19 was found. Consequently, many of the recommendations were based on indirect evidence and prior guidelines in similar populations without COVID-19.

INTERPRETATION

The existing evidence and panel consensus do not suggest a major departure from the management of arterial thrombosis according to recommendations predating the COVID-19 pandemic. Data on the optimal strategies for prevention and management of arterial thrombosis and thromboembolism in patients with COVID-19 are sparse. More high-quality evidence is needed to inform management strategies in these patients.

Lead activates neutrophil degranulation to induce early myocardial injury in mice

Lead (Pb) is a pervasive toxic metal contaminant associated with a high risk of myocardial injury. However, the precise mechanism underlying Pb-induced myocardial injury has yet to be fully elucidated. In this study, a murine model of Pb exposure (0, 1, 5, and 10 mg/kg) was employed to investigate the involvement of neutrophil degranulation in the induction of myocardial injury. Notably, serum levels of cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) increased significantly in Pb-exposed mice, whereas cTnI levels in cardiomyocytes decreased, suggesting that Pb exposure may cause early myocardial injury. Moreover, Pb exposure was found to promote neutrophil degranulation, as evidenced by elevated myeloperoxidase (MPO) and neutrophil elastase (NE) concentrations in both the serum of Pb-exposed workers and Pb-exposed mice, as well as the extracellular supernatant of neutrophils following exposure. However, we found that serum level of cTnI enhanced by Pb exposure is associated with increased NE levels in the serum, but not with MPO levels. Upon treatment with NE inhibitor (sivelestat), the serum level of cTnI markedly reduced in Pb-exposed mice, we found that early myocardial injury is associated with NE levels in the serum. At the molecular level, western blotting analysis revealed an upregulation of ERK1/2 expression in vitro following Pb exposure, suggesting that the activation of the ERK1/2 signaling pathway may underlie the participation of neutrophil degranulation in Pb-induced myocardial injury. In summary, our findings demonstrate that Pb exposure can initiate early myocardial injury by promoting the neutrophil degranulation process, thereby highlighting the potential role of this process in the pathogenesis of Pb-associated myocardial injury.

High-sensitivity Cardiac Troponin T Is a Useful Biomarker for Predicting the Prognosis of Patients with Systemic Sarcoidosis Regardless of Cardiac Involvement

Objective Cardiac involvement defines the prognosis for patients with systemic sarcoidosis. Despite advancements in techniques for diagnosing cardiac lesions, there remains significant room for improvement in cardiac screening and prognostic prediction. The present study therefore assessed the prognostic factors associated with cardiovascular events in patients with sarcoidosis. Methods We retrospectively studied 132 patients with systemic sarcoidosis and evaluated the clinical data obtained between 2009 and 2022. A Kaplan-Meier survival analysis and Cox proportional hazards models were used to evaluate the associations between cardiovascular events and prognostic factors. Results The median age of the patients at the diagnosis was 64.0 (55.0-71.0) years old. During a mean follow-up period of 6.3±3.2 years, 28 patients suffered from cardiovascular events. Patients in the event group had more severe heart failure symptoms, more frequent ventricular tachycardia, higher serum high-sensitivity cardiac troponin T (hs-cTnT) values [0.025 (0.017-0.044) vs. 0.011 (0.007-0.019) ng/mL, p<0.001], and lower left ventricular ejection fraction values than those in the non-event group. These trends were observed even if the patients were not diagnosed with cardiac involvement at the time of enrollment. A multivariate analysis revealed that hs-cTnT was an independent biomarker for the prediction of cardiac events (hs-cTnT >0.014 ng/mL: HR: 7.31, 95% confidence interval: 2.20 to 24.28, p<0.001). Conclusion Hs-cTnT is a useful biomarker for predicting cardiovascular events in patients with sarcoidosis, even if cardiac involvement is not detected at the initial evaluation.

The roles of intracellular proteolysis in cardiac ischemia-reperfusion injury

Ischemic heart disease remains a leading cause of human mortality worldwide. One form of ischemic heart disease is ischemia-reperfusion injury caused by the reintroduction of blood supply to ischemic cardiac muscle. The short and long-term damage that occurs due to ischemia-reperfusion injury is partly due to the proteolysis of diverse protein substrates inside and outside of cardiomyocytes. Ischemia-reperfusion activates several diverse intracellular proteases, including, but not limited to, matrix metalloproteinases, calpains, cathepsins, and caspases. This review will focus on the biological roles, intracellular localization, proteolytic targets, and inhibitors of these proteases in cardiomyocytes following ischemia-reperfusion injury. Recognition of the intracellular function of each of these proteases includes defining their activation, proteolytic targets, and their inhibitors during myocardial ischemia-reperfusion injury. This review is a step toward a better understanding of protease activation and involvement in ischemic heart disease and developing new therapeutic strategies for its treatment.

"Troponinosis", the Cardiologist's Curse-When Clinic-Laboratory Interaction Unveils the Mystery: A Case Report

Cardiac troponins are key diagnostic and prognostic biomarkers in acute myocardial infarction and, more generally, for the detection of myocardial injury. Since the introduction of the first immunochemistry methods, there has been a remarkable evolution in analytical performance, especially concerning a progressive improvement in sensitivity. However, the measurement of circulating troponins remains rarely susceptible to analytical interferences. We report a case of persistently elevated troponin I concentrations in a patient with known ischemic heart disease, which almost led to unnecessary diagnostic-therapeutic interventions. A prompt laboratory consultation by the cardiologist ultimately led to the identification of an analytical interference due to troponin macrocomplexes (macrotroponin) causing elevated troponin values in the absence of a clinical presentation compatible with myocardial damage.

Predictors of persistent symptoms after mRNA SARS-CoV-2 vaccine-related myocarditis (myovacc registry)

Aims

Epidemiological surveillance has raised safety concerns for mRNA SARS-CoV-2-vaccination-related myocarditis. We aimed to analyze epidemiological, clinical and imaging findings associated with clinical outcomes in these patients in an international multi-center registry (NCT05268458).

Methods and results

Patients with clinical and CMR diagnosis of acute myocarditis within 30 days after mRNA SARS-CoV-2-vaccination were included from five centers in Canada and Germany between 05/21 and 01/22. Clinical follow-up on persistent symptoms was collected. We enrolled 59 patients (80% males, mean age 29 years) with CMR-derived mild myocarditis (hs-Troponin-T 552 [249-1,193] ng/L, CRP 28 [13-51] mg/L; LVEF 57 ± 7%, LGE 3 [2-5] segments). Most common symptoms at baseline were chest pain (92%) and dyspnea (37%). Follow-up data from 50 patients showed overall symptomatic burden improvement. However, 12/50 patients (24%, 75% females, mean age 37 years) reported persisting symptoms (median interval 228 days) of chest pain (n = 8/12, 67%), dyspnea (n = 7/12, 58%), with increasing occurrence of fatigue (n = 5/12, 42%) and palpitations (n = 2/12, 17%). These patients had initial lower CRP, lower cardiac involvement in CMR, and fewer ECG changes. Significant predictors of persisting symptoms were female sex and dyspnea at initial presentation. Initial severity of myocarditis was not associated with persisting complaints.

Conclusion

A relevant proportion of patients with mRNA SARS-CoV-2-vaccination-related myocarditis report persisting complaints. While young males are usually affected, patients with persisting symptoms were predominantly females and older. The severity of the initial cardiac involvement not predicting these symptoms may suggest an extracardiac origin.

Association of triglyceride-glucose index with myocardial injury post-stroke in older patients with first-ever ischemic stroke

BACKGROUND

Myocardial injury post-stroke is a common sequela of acute stroke. Triglyceride-glucose index (TyG index), a valuable surrogate indicator of insulin resistance, has been suggested to be closely related to cardiovascular outcomes. However, it is unknown whether the TyG index is independently associated with a higher risk of myocardial injury post-stroke. We therefore investigated the longitudinal association between TyG index and risk of myocardial injury post-stroke in older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities.

METHODS

We included older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities between January 2021 to December 2021. The individuals were stratified into low and high TyG index groups according to the optimal cutoff value with TyG index. We performed logistic regression analysis, propensity score matching (PSM) analysis, restricted cubic spline analysis, and subgroup analyses to explore the longitudinal association between TyG index and risk of myocardial injury post-stroke.

RESULTS

We included 386 individuals with a median age of 69.8 years (interquartile range: 66.6, 75.3). The optimal TyG index cut-off for predicting myocardial injury post-stroke was 8.9 (sensitivity 67.8%; specificity 75.5%; area under curve 0.701). Multivariate logistic regression analysis revealed that the risk of genesis of myocardial injury post-stroke increased with elevated TyG index (odds ratio [OR], 2.333; 95% confidence interval [CI], 1.201-4.585; P = 0.013). Furthermore, all covariates were well balanced between the two groups. The longitudinal association between TyG index and myocardial injury post-stroke remained significantly robust (OR: 2.196; 95% CI: 1.416-3.478; P < 0.001) after PSM adjustment.

CONCLUSION

Individuals with an elevated TyG index were more susceptible to having an increased risk of myocardial injury post-stroke. TyG index thus might be served as a complementary approach for optimized-for-risk stratification in older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities.

Variation in ACS patient hospital resource utilization: Is it time for advanced NSTEMI risk stratification in the ED?

OBJECTIVES

A majority of patients who experience acute coronary syndrome (ACS) initially receive care in the emergency department (ED). Guidelines for care of patients experiencing ACS, specifically ST-segment elevation myocardial infarction (STEMI) are well defined. We examine the utilization of hospital resources between patients with NSTEMI as compared to STEMI and unstable angina (UA). We then make the case that as NSTEMI patients are the majority of ACS cases, there is a great opportunity to risk stratify these patients in the emergency department.

MATERIALS AND METHODS

We examined hospital resource utilization measure between those with STEMI, NSTEMI, and UA. These included hospital length of stay (LOS), any intensive care unit (ICU) care time, and in-hospital mortality.

RESULTS AND CONCLUSIONS

The sample included 284,945 adult ED patients, of whom 1195 experienced ACS. Among the latter, 978 (70%) were diagnosed with NSTEMI, 225 (16%) with STEMI, and 194 with UA (14%). We observed 79.1% of STEMI patients receiving ICU care. 14.4% among NSTEMI patients, and 9.3% among UA patients. NSTEMI patients' mean hospital LOS was 3.7 days. This was shorter than that of non-ACS patients 4.75 days and UA patients 2.99. In-hospital mortality for NSTEMI was 1.6%, compared to, 4.4% for those with STEMI patients and 0% for UA. There are recommendations for risk stratification among NSTEMI patients to evaluate risk for major adverse cardiac events (MACE) that can be used in the ED to guide admission decisions and use of ICU care, thus optimizing care for a majority of ACS patients.

Outcome of patients admitted with oxygen mismatch and myocardial injury or infarction in emergency departments

AIMS

To describe the outcomes and associated factors in a population of patients admitted to emergency departments with at least one condition of oxygen supply/demand imbalance, regardless of the troponin result or restrictive criteria for type 2 myocardial infarction.

METHODS

We constituted a retrospective cohort of 824 patients. Medical records of patients having undergone a troponin assay were reviewed for selection and classification, and data including in-hospital stay and readmissions were collected. The reported outcomes are in-hospital mortality, 3-year mortality, and major adverse cardiovascular events.

RESULTS

Patients with myocardial infarction or injury, either chronic or acute, were older, with more history of hypertension and chronic heart or renal failure but not for other cardiovascular risk factors and medical history. Acute myocardial injury and type 2 myocardial infarction were significantly associated with in-hospital mortality [odds ratio (OR) 3.71 95% confidence interval (CI) 1.90-7.33 and OR 3.15 95% CI 1.59-6.28, respectively]. However, the long-term mortality does not differ in comparison with patients presenting chronic myocardial injury or nonelevated troponin, ranging from 26.9 to 34.3%. Patients with chronic myocardial injury and type 2 myocardial infarction had more long-term major cardiovascular events (39.3 and 38.8%), but only for acute heart failure, and none was associated with this outcome after adjustment.

CONCLUSION

Among patients admitted to emergency departments with an oxygen supply/demand imbalance, acute myocardial injury and type 2 myocardial infarction are strongly associated with in-hospital mortality. However, they are not associated with higher long-term mortality or major cardiovascular events after discharge, which tend to occur in elderly people with comorbidities.

Computed tomography coronary angiography in non-ST-segment elevation myocardial infarction

Electrocardiography and high-sensitivity cardiac troponin testing are routinely applied as the initial step for clinical evaluation of patients with suspected non-ST-segment elevation myocardial infarction. Once diagnosed, patients with non-ST-segment elevation myocardial infarction are commenced on antithrombotic and secondary preventative therapies before undergoing invasive coronary angiography to determine the strategy of coronary revascularisation. However, this clinical pathway is imperfect and can lead to challenges in the diagnosis, management, and clinical outcomes of these patients. Computed tomography coronary angiography (CTCA) has increasingly been utilised in the setting of patients with suspected non-ST-segment elevation myocardial infarction, where it has an important role in avoiding unnecessary invasive coronary angiography and reducing downstream non-invasive functional testing for myocardial ischaemia. CTCA is an excellent gatekeeper for the cardiac catheterisation laboratory. In addition, CTCA provides complementary information for patients with myocardial infarction in the absence of obstructive coronary artery disease and highlights alternative or incidental diagnoses for those with cardiac troponin elevation. However, the routine application of CTCA has yet to demonstrate an impact on subsequent major adverse cardiovascular events. There are several ongoing studies evaluating CTCA and its associated technologies that will define and potentially expand its application in patients with suspected or diagnosed non-ST-segment elevation myocardial infarction. We here review the current evidence relating to the clinical application of CTCA in patients with non-ST-segment elevation myocardial infarction and highlight the areas where CTCA is likely to have an increasing important role and impact for our patients.

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.

Distinguishing Type 1 from Type 2 Myocardial Infarction by Using CT Coronary Angiography

Purpose

To determine whether quantitative plaque characterization by using CT coronary angiography (CTCA) can discriminate between type 1 and type 2 myocardial infarction.

Materials and Methods

This was a secondary analysis of two prospective studies (ClinicalTrials.gov registration nos. NCT03338504 [2014-2019] and NCT02284191 [2018-2020]) that performed blinded quantitative plaque analysis on findings from CTCA in participants with type 1 myocardial infarction, type 2 myocardial infarction, and chest pain without myocardial infarction. Logistic regression analyses were performed to identify predictors of type 1 myocardial infarction.

Results

Overall, 155 participants (mean age, 64 years ± 12 [SD]; 114 men) and 36 participants (mean age, 67 years ± 12; 19 men) had type 1 and type 2 myocardial infarction, respectively, and 136 participants (62 years ± 12; 78 men) had chest pain without myocardial infarction. Participants with type 1 myocardial infarction had greater total (median, 44% [IQR: 35%-50%] vs 35% [IQR: 29%-46%]), noncalcified (39% [IQR: 31%-46%] vs 34% [IQR: 29%-40%]), and low-attenuation (4.15% [IQR: 1.88%-5.79%] vs 1.64% [IQR: 0.89%-2.28%]) plaque burdens (P < .05 for all) than those with type 2. Participants with type 2 myocardial infarction had similar low-attenuation plaque burden to those with chest pain without myocardial infarction (P = .4). Low-attenuation plaque was an independent predictor of type 1 myocardial infarction (adjusted odds ratio, 3.44 [95% CI: 1.84, 6.96]; P < .001), with better discrimination than noncalcified plaque burden and maximal area of coronary stenosis (C statistic, 0.75 [95% CI: 0.67, 0.83] vs 0.62 [95% CI: 0.53, 0.71] and 0.61 [95% CI: 0.51, 0.70] respectively; P ≤ .001 for both).

Conclusion

Higher low-attenuation coronary plaque burden in patients with type 1 myocardial infarction may help distinguish these patients from those with type 2 myocardial infarction.Keywords: Ischemia/Infarction, CT Angiography, Quantitative CTClinical trial registration nos. NCT03338504 and NCT02284191 Supplemental material is available for this article. © RSNA, 2022.

Major adverse cardiovascular events after diagnosis of myocardial injury and types 1 and 2 myocardial infarction

AIMS

Limited US outcome data exist among patients with myocardial injury and types 1 and 2 myocardial infarction (MI) evaluated with high-sensitivity cardiac troponin (hs-cTn).

METHODS AND RESULTS

This is an observational US cohort study of emergency department (ED) patients undergoing hs-cTnT measurement. Cases with ≥1 hs-cTnT increase >99th percentile were adjudicated following the Fourth Universal Definition of MI. Post-discharge major adverse cardiovascular events (MACE) included death, MI, heart failure (HF) hospitalization, stroke or transient ischaemic attack, and new-onset atrial fibrillation or flutter during 2 years follow-up. Among 2002 patients, 857 (43%) had ≥1 hs-cTnT >99th percentile. Among these, 702 (81.9%) had myocardial injury, 64 (7.5%) had type 1 MI, and 91 (10.6%) had type 2 MI. Compared with patients without myocardial injury, type 2 MI [8.4 vs. 50%; adjusted hazard ratio (HR) 2.31, 95% confidence interval (CI) 1.49-3.58] and myocardial injury (8.4 vs. 47%; adjusted HR 3.13, 95% CI 2.39-4.09) had a higher risk of MACE, in large part because of death and HF hospitalizations. Compared with patients with type 1 MI, type 2 MI (23 vs. 50%; adjusted HR 2.24; 95% CI 1.23-4.10) and myocardial injury (23 vs. 47%; adjusted HR 2.02; 95% CI 1.20-3.40) also have a higher risk of MACE.

CONCLUSION

Among unselected US ED patients undergoing hs-cTnT measurement, most increases are due to myocardial injury, and type 2 MI is more frequent than type 1 MI. Patients with myocardial injury and type 2 MI have morbid outcomes, in large part due to death and HF.

A Real Pandora's Box in Pandemic Times: A Narrative Review on the Acute Cardiac Injury Due to COVID-19

The intricate relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the cardiovascular system is an extensively studied pandemic topic, as there is an ever-increasing amount of evidence that reports a high prevalence of acute cardiac injury in the context of viral infection. In patients with Coronavirus disease 2019, COVID-19, a significant increase in serum levels of cardiac troponin or other various biomarkers was observed, suggesting acute cardiac injury, thus predicting both a severe course of the disease and a poor outcome. Pathogenesis of acute cardiac injury is not yet completely elucidated, though several mechanisms are allegedly involved, such as a direct cardiomyocyte injury, oxygen supply-demand inequity caused by hypoxia, several active myocardial depressant factors during sepsis, and endothelial dysfunction due to the hyperinflammatory status. Moreover, the increased levels of plasma cytokines and catecholamines and a significantly enhanced prothrombotic environment may lead to the destabilization and rupture of atheroma plaques, subsequently triggering an acute coronary syndrome. In the present review, we focus on describing the epidemiology, pathogenesis, and role of biomarkers in the diagnosis and prognosis of patients with acute cardiac injury in the setting of the COVID-19 pandemic. We also explore some novel therapeutic strategies involving immunomodulatory therapy, as well as their role in preventing a severe form of the disease, with both the short-term outcome and the long-term cardiovascular sequelae being equally important in patients with SARS-CoV-2 induced acute cardiac injury.

Relation of High-Sensitivity Cardiac Troponin I and Obstructive Coronary Artery Disease in Patients Without Acute Myocardial Infarction

The relation of high-sensitivity cardiac troponin I (hs-cTnI) concentration and presence of obstructive coronary artery disease (CAD) in patients without myocardial infarction (MI) is unclear. Study participants selected from patients free of MI who underwent coronary angiography with or without intervention were enrolled, and hs-cTnI measured. A gradient boosting model was implemented to build a model for detection of CAD. Cox proportional hazard regression was used to assess the association of hs-cTnI and adverse cardiovascular (CV) outcome. Among 978 study participants, 607 patients (62%) had CAD. Higher concentrations of hs-cTnI were associated with chronic kidney disease, heart failure, CAD, male gender, current tobacco use, anemia, age, and low-density lipoprotein cholesterol. History of CAD, male gender, type 2 diabetes mellitus, hs-cTnI, anemia, age, and high-density lipoprotein cholesterol were the most influential factors for detection of CAD. The gradient boosting model had an area under the curve of 0.82, accuracy of 75%, sensitivity of 88%, specificity of 52%, positive predictive value of 76%, and negative predictive value of 72% for detection of CAD. Increase in 1 log unit of hs-cTnI was significantly associated with increased risk of incident MI (hazard ratio [HR] 1.34, 95% confidence interval [CI] 1.22 to 1.47, p <0.001), CV mortality (HR 1. 24, 95% CI 1.11 to 1.39, p <0.001), and composite of incident MI or CV mortality (HR 1.29, 95% CI 1.20 to 1.40, p <0.001). In conclusion, among patients without acute MI and CAD, higher concentrations of hs-cTnI were associated with the presence of CAD and linked to increased risk of future CV events. ClinicalTrials.gov Identifier: NCT00842868.

Serum troponin, D-dimer, and CRP level in severe coronavirus (COVID-19) patients

Background

Abnormal inflammation coagulation biomarker levels of troponin, C‐reactive protein (CRP), and D‐dimer levels in serum have been demonstrated to be associated and involved in the disease progression of coronavirus disease 2019 (COVID‐19).

Methods

First: the study aimed to investigate the correlation of troponin, CRP, d‐dimer, white blood cell (WBC) and polymerase chain reaction–cycle threshold (PCR‐Ct) within COVID‐19 survivors (143 patients; 79 males, 64 females) and in deceased (30 patients; 12 males, 18 females) group. Also, assessing any differences between both groups in studied parameters. Second: a correlation study of studied parameters' level has been conducted within families (41 patients; 23 males [seven deaths] and 18 females [eight deaths]) that lost more than one member due to the severity of the disease. Also, differences between these family and control group (132 patients; 69 males and 63 females) group in studied parameters have been assessed.

Results

In the first week of hospitalization, there were significant differences in D‐dimer, CRP and troponin level between survived and deceased patient groups. In the second week of the admission, both groups had significant differences in the level of all studied parameters; troponin I, D‐dimer, CRP, and WBCs. WBC levels positively correlated to CRP in male survivors (r = 0.75, p < 0.0001), and to troponin in deceased male patients (r = 0.74, p = 0.007). The second week of patient admission was critical in the group of families who lost more than one person, when troponin was correlated positively with D‐dimer, CRP, and WBCs.

Conclusion

Troponin, D‐dimer, CRP, and WBCs level were significantly higher in COVID‐19 patients who died than in COVID‐19 survivors. High troponin and WBC levels, were considerably associated with families that lost more than one member, when compared with the unrelated COVID‐19 patient control.

Clinical characteristics and outcome of elderly patients admitted in emergency department with an oxygen mismatch and type 2 myocardial infarction or myocardial injury

BACKGROUND

Aging is a risk factor for type 2 myocardial infarction or myocardial injury, but few data are available on the elderly. We aimed to determine the factors associated with these pathologies and mortality in the elderly population and its age classes.

METHODS

A retrospective cohort of all patients with oxygen mismatch (anemia, hypoxia, tachycardia, hypo/hypertension) for whom a troponin drawn was performed at admission in 2 emergency departments. Medical records were reviewed and classified as having type 2 myocardial infarction, acute or chronic myocardial injury, or no myocardial injury.

RESULTS

Of the 824 patients who presented with oxygen mismatch, 675 (81.9%) were older than 65 years. Age over 85 years was a risk factor for acute non-ischemic myocardial injury (odds ratio, 95% confidence interval 2.23, 1.34-3.73). Non-ischemic myocardial injury was associated with hypoxemia, tachycardia, and acute renal failure in those older than 85 years, but only with acute infection in the 75-84-year-old group. Type 2 myocardial infarction was associated only with acute renal failure in the oldest group and, in the 75-84-year-old group, with acute heart failure and shock. Patients older than 85 years with acute myocardial injury, with or without infarction, had a higher in-hospital mortality, but subsequently, mortality depends more on the comorbidities than on age.

CONCLUSION

Factors associated with type 2 myocardial infarction and acute non-ischemic myocardial injury in elderly admitted with oxygen mismatch vary notably between age classes. They are associated with in-hospital mortality but not with subsequent mortality when other cormorbities are taken into account.

Is cardiac Troponin I Considered as A Predictor of In-hospital Mortality among COVID-19 Patients? A Retrospective Cohort Study

Objective:

To describe the levels of troponin I in COVID-19 patients and its role in the prediction of their in-hospital mortality as a cardiac biomarker.

Methods:

The current retrospective cohort study was performed on the clinical records of 649 COVID-19-related hospitalized cases with at leat one positive polymerase chain reaction (PCR) test in Tehran, Iran from February 2020 to early June 2020. The on admission troponin I level divided into two groups of ≤0.03ng/mL (normal) and >0.03ng/mL (abnormal). The adjusted COX-regression model was used to determine the relationship between the studied variables and patient’s in-hospital mortality.

Results:

In this study, the median age of subjects was 65 years (54.8% men) and 29.53% of them had abnormal troponin I levels. Besides, the in-hospital mortality rate among patients with abnormal troponin I levels was found to be 51.56%; whereas, patients with normal levels exhibited 18.82% mortality. Also, the multivariable analysis indicated that the risk of death among hospitalized COVID-19 patients displaying abnormal troponin I levels was 67% higher than those with normal troponin I levels (Hazard ratio=1.67, 95% confidence interval=1.08-2.56, p=0.019).

Conclusion:

It seems that troponin I is one of the important factors related to in-hospital mortality of COVID-19 patients. Next, due to the high prevalence of cardiac complications in these patients, it is highly suggested to monitor and control cardiac biomarkers along with other clinical factors upon the patient’s arrival at the hospital.

Association between Cardiologist Consultation and Mortality of Stable Patients with Elevated Cardiac Troponin at Admission

Elevated cardiac troponin (cTn) showed associations with mortality even in stable patients, but management has not been established. We aimed to investigate whether consultation to cardiologists could reduce mortality of stable patients with cTn elevation at admission. We identified 1329 patients with elevated cTn level at hospitalization from outpatient clinic to any department other than cardiology or cardiac surgery between April 2010 and December 2018. The patients were divided into two groups according to cardiologist consultation at admission. For primary outcome, mortality during one year was compared in the crude and propensity-score-matched populations. In 1329 patients, 397 (29.9%) were consulted to cardiologists and 932 (70.1%) were not. Mortality during the first year was significantly lower in patients consulted to cardiologists compared with those who were not (9.8% vs. 14.2%; hazard ratio (HR), 0.50; 95% confidence interval (CI), 0.35-0.72; p < 0.001). After propensity-score matching, 324 patients were in the cardiologist consultation group and 560 patients were in the no cardiologist consultation group. One-year mortality was consistently lower in the cardiologist consultation group (10.5% vs. 14.6%; HR, 0.58; 95% CI, 0.39-0.86; p = 0.01). Cardiologist consultation may be associated with lower mortality in stable patients with cTn elevation at admission. Further studies are needed to identify effective management strategies for stable patients with elevated cTn.

A review on the molecular basis underlying the protective effects of Andrographis paniculata and andrographolide against myocardial injury

Andrographolide is the major compound found in the medicinal plant, Andrographis paniculata (Burm.f.) Nees, which accounts for its medicinal properties. Both the plant extract and compound have been reported to exhibit potential cardiovascular activities. This review summarises related studies describing the biological activities and target mechanisms of A. paniculata and andrographolide in vivo and in vitro. The current evidence unambiguously indicated the protective effects provided by A. paniculata and andrographolide administration against myocardial injury. The intervention ameliorates the symptoms of myocardial injury by interfering with the inductive phase of a) inflammatory response mediated by nuclear factor-kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signalling molecules; b) oxidative stress via activation of nuclear factor erythroid 2-related factor (Nrf-2) and reduction of enzymes responsible for generating reactive oxygen and nitrogen species; c) intrinsic and extrinsic mechanisms in apoptosis regulated by upstream insulin-like growth factor-1 receptor (IGF-1R) and peroxisome proliferator-activated receptor-alpha (PPAR-α); d) profibrotic growth factors thus reducing cardiac fibrosis, improving endothelial function and fibrinolytic function. In conclusion, A. paniculata and andrographolide possess therapeutic potential in the management of myocardial injury, which requires further validation in human clinical trials.

Etiology of Myocardial Injury in Critically Ill Patients with Sepsis: A Cohort Study

RATIONALE

Myocardial injury occurs frequently during sepsis and is independently associated with mortality. However, its etiology remains largely unknown.

OBJECTIVE

Our aim was to assess the relative contributions of hyperinflammation, activated coagulation, and endothelial dysfunction to myocardial injury in critically ill patients with sepsis.

METHODS

We included consecutive patients with sepsis presenting to two tertiary intensive care units in the Netherlands between 2011 and 2013. High-sensitivity cardiac troponin I (hscTnI), as well as a wide range of plasma biomarkers related to inflammation, coagulation, and endothelial function were measured. Structural equation modeling (SEM) was used to construct latent variables representing each of these pathophysiological constructs, and to subsequently study their associations with troponin elevation while adjusting for confounders.

RESULTS

We analyzed 908 (88%) of 1037 eligible patients, 553 (61%) of whom had raised hs-cTnI levels upon intensive care unit admission. The latent variables included interleukin (IL)-6, IL-8 and IL-1β for inflammation; platelet count, prothrombin time and protein C for coagulation; and sE-selectin, intercellular adhesion molecule-1 and angiopoietin-2 for endothelial function. After adjustment for age and cardiovascular comorbidities, SEM analysis showed that activated coagulation was independently associated with elevated troponin during sepsis (standardized regression coefficient 0.551, 95% CI 0.257-0.845, p-value <0.001), whereas hyperinflammation and endothelial dysfunction were not (standardized regression coefficients -0.161, 95% CI -0.418-0.096, and -0.054, 95% CI -0.168-0.060, respectively).

CONCLUSIONS

Our findings suggest that myocardial injury during sepsis is mediated by systemic activation of coagulation, rather than by circulating inflammatory mediators or by activation of the endothelium. These findings may guide evaluation of strategies to protect the myocardium during sepsis. Clinical trial registered with clinicaltrials.gov (NCT01905033).

Genome-wide association study of cardiac troponin I in the general population

Circulating cardiac troponin proteins are associated with structural heart disease and predict incident cardiovascular disease in the general population. However, the genetic contribution to cardiac troponin I (cTnI) concentrations and its causal effect on cardiovascular phenotypes are unclear. We combine data from two large population-based studies, the Trøndelag Health Study and the Generation Scotland Scottish Family Health Study, and perform a genome-wide association study of high-sensitivity cTnI concentrations with 48 115 individuals. We further use two-sample Mendelian randomization to investigate the causal effects of circulating cTnI on acute myocardial infarction (AMI) and heart failure (HF). We identified 12 genetic loci (8 novel) associated with cTnI concentrations. Associated protein-altering variants highlighted putative functional genes: CAND2, HABP2, ANO5, APOH, FHOD3, TNFAIP2, KLKB1 and LMAN1. Phenome-wide association tests in 1688 phecodes and 83 continuous traits in UK Biobank showed associations between a genetic risk score for cTnI and cardiac arrhythmias, metabolic and anthropometric measures. Using two-sample Mendelian randomization, we confirmed the non-causal role of cTnI in AMI (5948 cases, 355 246 controls). We found indications for a causal role of cTnI in HF (47 309 cases and 930 014 controls), but this was not supported by secondary analyses using left ventricular mass as outcome (18 257 individuals). Our findings clarify the biology underlying the heritable contribution to circulating cTnI and support cTnI as a non-causal biomarker for AMI in the general population. Using genetically informed methods for causal inference helps inform the role and value of measuring cTnI in the general population.

Insomnia symptoms and subclinical myocardial injury: Data from the Nord-Trøndelag Health (HUNT) study

Insomnia symptoms are associated with increased risk of heart failure (HF) and cardiovascular (CV) mortality. We hypothesised that insomnia symptoms are cross-sectionally associated with increased cardiac troponin I (cTnI), a biomarker of subclinical myocardial injury, and that phenotyping by insomnia symptoms and cTnI enhances longitudinal risk stratification in the general population. In a population-based study, cTnI was measured in 8,398 participants (median age 49 years, 55% women), who had answered questionnaires regarding insomnia symptoms. Association between cTnI and insomnia symptoms was assessed by linear regression analysis for each response category of a sleep questionnaire. Insomnia symptoms were defined as having difficulty falling asleep almost every night, difficulty maintaining sleep almost every night, and/or non-restorative sleep once a week or more. The primary outcome measure was a composite endpoint of CV mortality or first admission for HF. In all, 844 participants reported insomnia symptoms, 585 (69%) were women. Those with insomnia symptoms had marginally, but significantly higher median cTnI than those without insomnia symptoms, (median [interquartile range] 3.4 [2.4-5.2] ng/L versus 3.2 [2.2-4.9] ng/L; p = .014), but there was no association between any insomnia symptom and cTnI in unadjusted linear regression models (β 0.06, 95% confidence interval [CI] -0.01 to 0.12). In adjusted analyses, participants with insomnia symptoms and increased cTnI were at increased risk of the composite endpoint (hazard ratio 1.71, 95% CI 1.04-2.79) compared to participants with insomnia symptoms and low cTnI. In the general population, insomnia symptoms are not associated with biochemical evidence of subclinical myocardial injury.

Hospitalizations and Outcomes of T1MI Observed Before and After the Introduction of MI Subtype Codes

BACKGROUND

International Classification of Disease (ICD)-10 coding of type 1 myocardial infarction (MI) is used for reimbursement, value-based programs, and clinical research.

OBJECTIVES

This study sought to determine whether the introduction of ICD-10 codes for type 2 and types 3-5 MI was associated with changes in hospitalizations for ICD-10 codes now attributed to type 1 MI.

METHODS

Using the Nationwide Readmissions Database, we identified patients with ICD-10 codes now attributed to type 1 MI between January 2016 and December 2018. Patients were stratified according to the timing of their event in relation to the introduction of the type 2 and types 3-5 MI codes on October 1, 2017.

RESULTS

There were 2,680,323 hospitalizations for ICD-10 codes now attributed to type 1 MI; after adjustment for seasonality, there was a 13.7% decline in hospitalizations after the introduction of the new subtype codes. Patients with ICD-10 codes now attributed to type 1 MI after the coding change were less likely to be female, had lower prevalence of several cardiovascular and noncardiovascular comorbidities, and had higher rates of coronary angiography and revascularization. After introduction of the new codes, there was a positive deflection in the slope of risk-adjusted in-hospital mortality (0.007%; P <0.001) and a negative deflection in risk-adjusted 30-day readmission (-0.002%; P = 0.05) for patients with ICD-10 codes now attributed to type 1 MI.

CONCLUSIONS

The introduction of ICD-10 codes for type 2 and types 3-5 MI was associated with a decrease in hospitalizations for ICD-10 codes now attributed to type 1 MI and changes in the observed characteristics and treatment patterns of these patients.

Incidence and outcomes of perioperative myocardial infarction/injury diagnosed by high-sensitivity cardiac troponin I

BACKGROUND

 Perioperative myocardial infarction/injury (PMI) diagnosed by high-sensitivity troponin (hs-cTn) T is frequent and a prognostically important complication of non-cardiac surgery. We aimed to evaluate the incidence and outcome of PMI diagnosed using hs-cTnI, and compare it to PMI diagnosed using hs-cTnT.

METHODS

We prospectively included 2455 patients at high cardiovascular risk undergoing 3111 non-cardiac surgeries, for whom hs-cTnI and hs-cTnT concentrations were measured before surgery and on postoperative days 1 and 2. PMI was defined as a composite of perioperative myocardial infarction (PMIInfarct) and perioperative myocardial injury (PMIInjury), according to the Fourth Universal Definition of Myocardial Infarction. All-cause mortality was the primary endpoint.

RESULTS

Using hs-cTnI, the incidence of overall PMI was 9% (95% confidence interval [CI] 8-10%), including PMIInfarct 2.6% (95% CI 2.0-3.2) and PMIInjury 6.1% (95% CI 5.3-6.9%), which was lower versus using hs-cTnT: overall PMI 15% (95% CI 14-16%), PMIInfarct 3.7% (95% CI 3.0-4.4) and PMIInjury 11.3% (95% CI 10.2-12.4%). All-cause mortality occurred in 52 (2%) patients within 30 days and 217 (9%) within 1 year. Using hs-cTnI, both PMIInfarct and PMIInjury were independent predictors of 30-day all-cause mortality (adjusted hazard ratio [aHR] 2.5 [95% CI 1.1-6.0], and aHR 2.8 [95% CI 1.4-5.5], respectively) and, 1-year all-cause mortality (aHR 2.0 [95% CI 1.2-3.3], and aHR 1.8 [95% CI 1.2-2.7], respectively). Overall, the prognostic impact of PMI diagnosed by hs-cTnI was comparable to the prognostic impact of PMI using hs-cTnT.

CONCLUSIONS

Using hs-cTnI, PMI is less common versus using hs-cTnT. Using hs-cTnI, both PMIInfarct and PMIInjury remain independent predictors of 30-day and 1-year mortality.

Performance of the GRACE 2.0 score in patients with type 1 and type 2 myocardial infarction

AIMS

The Global Registry of Acute Coronary Events (GRACE) score was developed to evaluate risk in patients with myocardial infarction. However, its performance in type 2 myocardial infarction is uncertain.

METHODS AND RESULTS

In two cohorts of consecutive patients with suspected acute coronary syndrome from 10 hospitals in Scotland (n = 48 282) and a tertiary care hospital in Sweden (n = 22 589), we calculated the GRACE 2.0 score to estimate death at 1 year. Discrimination was evaluated by the area under the receiver operating curve (AUC), and compared for those with an adjudicated diagnosis of type 1 and type 2 myocardial infarction using DeLong's test. Type 1 myocardial infarction was diagnosed in 4981 (10%) and 1080 (5%) patients in Scotland and Sweden, respectively. At 1 year, 720 (15%) and 112 (10%) patients died with an AUC for the GRACE 2.0 score of 0.83 [95% confidence interval (CI) 0.82-0.85] and 0.85 (95% CI 0.81-0.89). Type 2 myocardial infarction occurred in 1121 (2%) and 247 (1%) patients in Scotland and Sweden, respectively, with 258 (23%) and 57 (23%) deaths at 1 year. The AUC was 0.73 (95% CI 0.70-0.77) and 0.73 (95% CI 0.66-0.81) in type 2 myocardial infarction, which was lower than for type 1 myocardial infarction in both cohorts (P < 0.001 and P = 0.008, respectively).

CONCLUSION

The GRACE 2.0 score provided good discrimination for all-cause death at 1 year in patients with type 1 myocardial infarction, and moderate discrimination for those with type 2 myocardial infarction.

TRIAL REGISTRATION

ClinicalTrials.gov number, NCT01852123.

Acute pulmonary hypertension and short-term outcomes in severe Covid-19 patients needing intensive care

Introduction

Critically ill Covid‐19 pneumonia patients are likely to develop the sequence of acute pulmonary hypertension, right ventricular (RV) strain, and eventually RV failure due to known pathophysiology (endothelial inflammation plus thrombo‐embolism) that promotes increased pulmonary vascular resistance and pulmonary artery pressure. This study aimed to investigate the occurrence of acute pulmonary hypertension (aPH) as per established trans‐thoracic echocardiography (TTE) criteria in Covid‐19 patients receiving intensive care and to explore whether short‐term outcomes are affected by the presence of aPH.

Methods

Medical records were reviewed for patients treated in the intensive care units at a tertiary university hospital over a month. The presence of aPH on the TTE was noted, and plasma NTproBNP and troponin were measured as markers of cardiac failure and myocardial injury, respectively. Follow‐up data were collected 21 d after the performance of TTE.

Results

In total, 26 of 67 patients (39%) had an assessed systolic pulmonary artery pressure of > 35 mmHg (group aPH), meeting the TTE definition of aPH. NTproBNP levels (median [range]: 1430 [102‐30 300] vs. 470 [45‐29 600] ng L⁻¹; P = .0007), troponin T levels (63 [22‐352] vs. 15 [5‐407] ng L⁻¹; P = .0002), and the 21‐d mortality rate (46% vs. 7%; P < .001) were substantially higher in patients with aPH compared to patients not meeting aPH criteria.

Conclusion

TTE‐defined acute pulmonary hypertension was frequently observed in severely ill Covid‐19 patients. Furthermore, aPH was linked to biomarker‐defined myocardial injury and cardiac failure, as well as an almost sevenfold increase in 21‐d mortality.

Chronic inflammatory diseases and coronary heart disease: Insights from cardiovascular CT

Epidemiological and clinical studies have demonstrated a consistent relationship between increased systemic inflammation and increased risk of cardiovascular events. In chronic inflammatory states, traditional risk factors only partially account for the development of coronary artery disease (CAD) but underestimate total cardiovascular risk likely due to the residual risk of inflammation. Computed coronary tomography angiography (CCTA) may aid in risk stratification by noninvasively capturing early CAD, identifying high risk plaque morphology and quantifying plaque at baseline and in response to treatment. In this review, we focus on reviewing studies on subclinical atherosclerosis by CCTA in individuals with chronic inflammatory conditions including rheumatoid arthritis (RA), systemic lupus erythematous (SLE), human immunodeficiency virus (HIV) infection and psoriasis. We start with a brief review on the role of inflammation in atherosclerosis, highlight the utility of using CCTA to delineate vessel wall and plaque characteristics and discuss combining CCTA with laboratory studies and emerging technologies to complement traditional risk stratification in chronic inflammatory states.

Release Profile of Cardiac Troponin T and Risk Factors of Postoperative Myocardial Injury in Patients Undergoing CABG

Background

Cardiac troponin T (cTnT) is currently one of the important indicators for clinical diagnosis of myocardial injury, which is inevitable in cardiac surgery, especially coronary artery bypass grafting (CABG). Describing the release profile of cTnT and finding out the risk factors of postoperative myocardial injury (PMI) are of great significance. The purposes of this study are to explore the release profile of cTnT in patients undergoing CABG and to search for independent risk factors of PMI.

Methods

In this retrospective study, clinical data of CABG patients were collected. The cTnT was measured at 24 hours before and 6, 12, 24, 48, 72, 96 and 120 hours after operation separately. The release profiles and peak time of cTnT in total cohort and sub-cohorts were observed. Independent risk factors of PMI were explored via univariate and multivariate logistic regression analyses.

Results

In total, 2084 patients were enrolled, including 998 patients in a cTnT group and 1086 patients in a high-sensitive cTnT (hs-cTnT) group. PMI was recognized in 797 patients. In both groups, cTnT showed a trend of rising first and then falling within 120 hours after operation. The peak cTnT appeared within 12–24 hours after operation, while the peak hs-cTnT occurred mostly within 24–48 hours after operation. Univariate logistic analysis showed that body mass index (BMI), New York Heart Association (NYHA) classification, coronary artery disease (CAD) classification, cerebrovascular disease, left ventricular ejection fraction, number of diseased vessels, valvular disease, intra-aortic balloon pump (IABP) implantation, chronic obstructive pulmonary disease, pulmonary hypertension, previous percutaneous coronary intervention (PCI), BMI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT were related risk factors. Multivariate logistic regression analysis showed that NYHA classification, CAD classification, valvular disease, IABP implantation, pulmonary hypertension, previous PCI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT were independent risk factors of PMI.

Conclusion

NYHA classification, CAD classification, valvular disease, IABP implantation, pulmonary hypertension, previous PCI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT are independent risk factors of PMI in patients undergoing CABG.

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.