Takotsubo cardiomyopathy has a unique cardiac biomarker profile: NT-proBNP/myoglobin and NT-proBNP/troponin T ratios for the differential diagnosis of acute coronary syndromes and stress induced cardiomyopathy

Animal models of Takotsubo syndrome: bridging the gap to the human condition

Modelling human diseases serves as a crucial tool to unveil underlying mechanisms and pathophysiology. Takotsubo syndrome (TS), an acute form of heart failure resembling myocardial infarction, manifests with reversible regional wall motion abnormalities (RWMA) of the ventricles. Despite its mortality and clinical similarity to myocardial infarction, TS aetiology remains elusive, with stress and catecholamines playing central roles. This review delves into current animal models of TS, aiming to assess their ability to replicate key clinical traits and identifying limitations. An in-depth evaluation of published animal models reveals a variation in the definition of TS among studies. We notice a substantial prevalence of catecholamine-induced models, particularly in rodents. While these models shed light on TS, there remains potential for refinement. Translational success in TS research hinges on models that align with human TS features and exhibit the key features, including transient RWMA. Animal models should be comprehensively evaluated regarding the various systemic changes of the applied trigger(s) for a proper interpretation. This review acts as a guide for researchers, advocating for stringent TS model standards and enhancing translational validity.

A Portable Readout System for Biomarker Detection with Aptamer-Modified CMOS ISFET Array

Biosensors based on ion-sensitive field effect transistors (ISFETs) combined with aptamers offer a promising and convenient solution for point-of-care testing applications due to the ability for fast and label-free detection of a wide range of biomarkers. Mobile and easy-to-use readout devices for the ISFET aptasensors would contribute to further development of the field. In this paper, the development of a portable PC-controlled device for detecting aptamer-target interactions using ISFETs is described. The device assembly allows selective modification of individual ISFETs with different oligonucleotides. Ta2O5-gated ISFET structures were optimized to minimize trapped charge and capacitive attenuation. Integrated CMOS readout circuits with linear transfer function were used to minimize the distortion of the original ISFET signal. An external analog signal digitizer with constant voltage and superimposed high-frequency sine wave reference voltage capabilities was designed to increase sensitivity when reading ISFET signals. The device performance was demonstrated with the aptamer-driven detection of troponin I in both reference voltage setting modes. The sine wave reference voltage measurement method reduced the level of drift over time and enabled a lowering of the minimum detectable analyte concentration. In this mode (constant voltage 2.4 V and 10 kHz 0.1Vp-p), the device allowed the detection of troponin I with a limit of detection of 3.27 ng/mL. Discrimination of acute myocardial infarction was demonstrated with the developed device. The ISFET device provides a platform for the multiplexed detection of different biomarkers in point-of-care testing.

Comparison of troponin and natriuretic peptides in Takotsubo syndrome and acute coronary syndrome: a meta-analysis

OBJECTIVE

Takotsubo syndrome (TTS) is an acute heart failure syndrome which resembles acute coronary syndrome (ACS) at presentation. Differentiation requires coronary angiography, but where this does not occur immediately, cardiac biomarkers may provide additional utility. We performed a meta-analysis to compare troponin and natriuretic peptides (NPs) in TTS and ACS to determine if differences in biomarker profile can aid diagnosis.

METHODS

We searched five literature databases for studies reporting NPs (Brain NP (BNP)/NT-pro-BNP) or troponin I/T in TTS and ACS, identifying 28 studies for troponin/NPs (5618 and 1145 patients, respectively).

RESULTS

Troponin was significantly lower in TTS than ACS (standardised mean difference (SMD) -0.86; 95% CI, -1.08 to -0.64; p<0.00001), with an absolute difference of 75 times the upper limit of normal (×ULN) higher in ACS than TTS. Conversely, NPs were significantly higher in TTS (SMD 0.62; 95% CI, 0.44 to 0.80; p<0.00001) and 5.8×ULN greater absolutely. Area under the curve (AUC) for troponin in ACS versus TTS was 0.82 (95% CI, 0.70 to 0.93), and 0.92 (95% CI, 0.80 to 1.00) for ST-segment elevation myocardial infarction versus TTS. For NPs, AUC was 0.69 (95% CI, 0.48 to 0.89). Combination of troponin and NPs with logistic regression did not improve AUC. Recursive Partitioning and Regression Tree analysis calculated a troponin threshold ≥26×ULN that identified 95% cases as ACS where and specificity for ACS were 85.71% and 53.57%, respectively, with 94.32% positive predictive value and 29.40% negative predictive value.

CONCLUSIONS

Troponin is lower and NPs higher in TTS versus ACS. Troponin had greater power than NPs at discriminating TTS and ACS, and with troponin ≥26×ULN patients are far more likely to have ACS.

NT-proBNP/cardiac troponin T ratio >7.5 on the second day of admission can differentiate Takotsubo from acute coronary syndrome with good accuracy

BACKGROUND

Takotsubo syndrome (TTS) is not usually diagnosed until patients with suspected acute coronary syndrome (ACS) and echocardiographically detected apical aneurysm are found to have "normal" coronary angiography (CA). Our aim was to explore whether cardiac biomarkers can contribute to the early diagnosis of TTS.

METHODS

Ratios of N-terminal-pro brain natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (cTnT) both expressed in pg/mL [admission and the 3 following days] were compared in 38 patients with TTS and 114 ACS patients of whom 58 had non-ST-elevation myocardial infarction (NSTEMI).

RESULTS

NT-proBNP/cTnT ratio at admission and during the following 3 days was significantly higher in TTS compared to patients with ACS [18.4 (8.7-41.7) vs 2.9 (0.8-6.8), 29.6 (14.3-53.7) vs 1.2 (0.5-2.7), 30.0 (11.6-50.9) vs 1.7 (0.5-3.0), 27.8 (11.3-42.6) vs 1.4 (0.6-2.8), respectively, all <0.001]. Βest discrimination of TTS from ACS was possible with the ratio of NT-proBNP/cTnT on the 2nd day. A cut-off value of NT-proBNP/cTnT ratio >7.5 had a sensitivity of 97.3%, a specificity of 95.4% and an accuracy of ∼96% in detecting TTS as opposed to ACS. Furthermore, the ratio of NT-proBNP/cTnT preserved its discriminatory value in the subgroup of patients with NSTEMI. In particular, an NT-proBNP/cTnT ratio >7.5 on the 2nd day had a sensitivity of 97.3%, a specificity of 91.4%, and an accuracy of 93.7% in differentiating TTS from NSTEMI.

CONCLUSIONS

An NT-proBNP/cTnT ratio >7.5 on the 2nd day of admission can be useful for the early identification of TTS among selected patients initially presenting with ACS, a ratio more clinically useful in the setting of NSTEMI.

Takotsubo Syndrome and Coronary Artery Disease: Which Came First-The Chicken or the Egg?

Takotsubo syndrome (TTS) is a clinical condition characterized by temporary regional wall motion anomalies and dysfunction that extend beyond a single epicardial vascular distribution. Various pathophysiological mechanisms, including inflammation, microvascular dysfunction, direct catecholamine toxicity, metabolic changes, sympathetic overdrive-mediated multi-vessel epicardial spasms, and transitory ischemia may cause the observed reversible myocardial stunning. Despite the fact that TTS usually has an acute coronary syndrome-like pattern of presentation, the absence of culprit atherosclerotic coronary artery disease is often reported at coronary angiography. However, the idea that coronary artery disease (CAD) and TTS conditions are mutually exclusive has been cast into doubt by numerous recent studies suggesting that CAD may coexist in many TTS patients, with significant clinical and prognostic repercussions. Whether the relationship between CAD and TTS is a mere coincidence or a bidirectional cause-and-effect is still up for debate, and misdiagnosis of the two disorders could lead to improper patient treatment with unfavourable outcomes. Therefore, this review seeks to provide a profound understanding of the relationship between CAD and TTS by analyzing potential common underlying pathways, addressing challenges in differential diagnosis, and discussing medical and procedural techniques to treat these conditions appropriately.

Influence of cardiac biomarkers on predicting significant coronary artery disease in hypertrophic cardiomyopathy patients

BACKGROUND

In this study, our aim was to investigate the role of cardiac biomarkers in predicting the presence of significant coronary artery disease in hypertrophic cardiomyopathy (HCM) patients.

METHODS

The study population was composed of hypertrophic cardiomyopathy patients who underwent coronary angiography at a single center between June 2021 and March 2023, and whose cardiac biomarkers were evaluated before the procedure. HCM patients were screened retrospectively. Significant CAD was defined as > 50% stenosis of the left main coronary artery or > 70% stenosis in a major coronary vessel. Demographic, echocardiographic and cardiac biomarker values were compared between the two groups.

RESULTS

A total of 123 patients were evaluated. Significant CAD was detected in 39 (31.7%) patients. Patients with significant CAD had higher CK-MB values than those without CAD [2.8 (2.1-4.0) vs. 3.4 (2.8-4.6), p = 0.036], and a higher level of high-sensitivity troponin T (hs-TnT) than those without CAD (24 vs. 17.8, p = 0.022). the NT-proBNP/hs-TnT ratio was found to be significantly lower in patients with CAD than in those with CAD (31.4 vs. 21.4, p = 0.019). In multivariate anaylsis, NT-proBNP/hs-TnT was determined as an independent predictor for significant CAD. In ROC analysis, NT-proBNP/hs-TnT ratio lower than the cut-off value of 30.7 could detect the presence of significant CAD with 76.9% sensitivity and 53.6% specificity (AUC: 0.632, 95% CI: 0.528-0.736, p = 0.019).

CONCLUSION

To sum up, we suggest that cardiac biomarkers were valuable and simple parameters in terms of significant CAD in HCM patients.

Presumed Takotsubo syndrome is associated with high in-hospital mortality in very elderly frail females: a case series

Given the aging of general population, very elderly females with Takotsubo syndrome (TTS) are not rarely encountered in clinical practice. Although coronary angiography with left ventriculography is the gold standard diagnostic tool to exclude or confirm TTS, currently, this invasive procedure is less frequently performed in older patients with several comorbidities, such as renal failure, anemia, infections, neurological disorders, malignancy, and severe frailty. In these patients, a "presumed" TTS is diagnosed on the basis of clinical presentation, electrocardiogram, cardiac biomarkers, and echocardiographic findings without coronary angiography. While, in younger patients, TTS is generally a benign condition, in very elderly females, it is associated with higher in-hospital mortality and poor prognosis. Herein, we present four cases of ultra-octogenarian females diagnosed with "presumed TTS", who did not undergo coronary angiography due to severe frailty and multiple comorbidities and who exhibited poor outcome. This could arise the question if an early more aggressive approach could have changed final results. Probably, the solution could only be a personalized decision deriving from a profound and detailed discussion of each case through a multidisciplinary team approach.

Molecular Mechanisms of Takotsubo Syndrome

Takotsubo syndrome (TTS) is a severe but reversible acute heart failure syndrome that occurs following high catecholaminergic stress. TTS patients are similar to those with acute coronary syndrome, with chest pain, dyspnoea and ST segment changes on electrocardiogram, but are characterised by apical akinesia of the left ventricle, with basal hyperkinesia in the absence of culprit coronary artery stenosis. The pathophysiology of TTS is not completely understood and there is a paucity of evidence to guide treatment. The mechanisms of TTS are thought to involve catecholaminergic myocardial stunning, microvascular dysfunction, increased inflammation and changes in cardiomyocyte metabolism. Here, we summarise the available literature to focus on the molecular basis for the pathophysiology of TTS to advance the understanding of the condition.

The Octopus Trap of Takotsubo and Stroke: Genetics, Biomarkers and Clinical Management

Takotsubo cardiomyopathy (TC) is a reversible cardiomyopathy mimicking an acute coronary syndrome, usually observed in response to acute stress situations. The association between acute ischemic stroke and TC is already known, since it has been previously reported that ischemic stroke can be both a consequence and a potential cause of TC. However, the precise pathophysiological mechanism linking the two conditions is still poorly understood. The aim of our review is to expand insights regarding the genetic susceptibility and available specific biomarkers of TC and to investigate the clinical profile and outcomes of patients with TC and stroke. Since evidence and trials on TC and stroke are currently lacking, this paper aims to fill a substantial gap in the literature about the relationship between these pathologies.

COVID-19 and the Heart: Could Transient Takotsubo Cardiomyopathy Be Related to the Pandemic by Incidence and Mechanisms?

Typical emergency hospital care during the COVID-19 pandemic has centered on pulmonary-focused services. Nonetheless, patients with COVID-19 frequently develop complications associated with the dysfunction of other organs, which may greatly affect prognosis. Preliminary evidence suggests that cardiovascular involvement is relatively frequent in COVID-19 and that it correlates with significant worsening of clinical status and mortality in infected patients. In this article, we summarize current knowledge on the cardiovascular effects of COVID-19. In particular, we focus on the association between COVID-19 and transient takotsubo cardiomyopathy (TTC)—two conditions that preliminarily seem epidemiologically associated—and we highlight cardiovascular changes that may help guide future investigations toward full discovery of this new, complex disease entity. We hypothesize that coronary endothelial dysfunction, along with septic state, inflammatory storm, hypercoagulability, endothelial necrosis, and small-vessel clotting, may represent a fundamental hidden link between COVID-19 and TTC. Furthermore, given the likelihood that new genetic mutations of coronaviruses or other organisms will cause similar pandemics and endemics in the future, we must be better prepared so that a substantial complication such as TTC can be more accurately recognized, its pathophysiology better understood, and its treatment made more justifiable, timely, and effective.

Takotsubo cardiomyopathy: A comprehensive review

Takotsubo cardiomyopathy (TCM), also known as stress cardiomyopathy, occurs in the setting of catecholamine surge from an acute stressor. This cardiomyopathy mimics acute myocardial infarction in the absence of coronary disease. The classic feature of TCM is regional wall motion abnormalities with characteristic ballooning of the left ventricle. The etiology of the stressor is often physical or emotional stress, however iatrogenic causes of TCM have been reported in the literature. In our review, we discuss medications, primarily the exogenous administration of catecholamines, and a wide array of procedures with subsequent development of iatrogenic cardiomyopathy. TCM is unique in that it is transient and has favorable outcomes in most individuals. Classically, beta-blockers and ACE-inhibitors have been prescribed in individuals with cardiomyopathy; however, unique to TCM, no specific treatment is required other than temporary supportive measures as this process is transient. Additionally, no improvement in mortality or recurrence have been reported in patients on these drugs. The aim of this review is to elucidate on the iatrogenic causes of TCM, allowing for prompt recognition and management by clinicians.

Update of Takotsubo cardiomyopathy: Present experience and outlook for the future

Takotsubo cardiomyopathy (TTS) has become a recognised clinical entity since the Japanese scientist Sato first described it in 1990. Despite an increasing number of confirmed cases, especially during the COVID-19 pandemic, its pathophysiology remains incompletely understood, and decision-making differs in the diagnosis and treatment. In addition, it is not evident whether a significant increase in TTS is due to better understanding among practitioners and widespread access to coronary angiography, or if it is a reflection of an actual increase in incidence. We analysed a series of international research studies from 1990 to 2021. Beyond epidemiology and clinical presentation, we evaluated and summarised fundamental knowledge about various predisposing factors, with particular attention to the iatrogenic impact of certain drugs, namely antidepressants, chemotherapy, and antiarrhythmics. Furthermore, we highlighted the main pathophysiological theories to date. In addition, based on published studies and clinical cases, we investigated the role of numerous diagnostic approaches in the differential diagnosis of TTS and identified predictors of TTS complications, such as cardiogenic shock, ventricular fibrillation, and left ventricular thrombi. Accordingly, we sought to propose a diagnostic algorithm and further treatment management of TTS under the presence of possible complications to help practitioners make more informed decisions, as the initial presentation continues to pose a challenge due to its close similarity to acute coronary syndrome with ST-elevation. In conclusion, this article examines Takotsubo cardiomyopathy from different perspectives and, along with future systematic reviews and meta-analyses, can be of particular interest to practising cardiologists and researchers in developing clinical guidelines.

Inverted Takotsubo Syndrome With HELLP Syndrome: A Case Report

Background

Takotsubo syndrome is an acute cardiac condition involving sudden, transient apical ballooning of the left ventricle of the heart that may be triggered by emotional stress and some non-cardiac conditions. Its diagnosis is based on clinical presentation, electrocardiogram, cardiac imaging and biomarkers.

Case Summary

Here, we present a novel and original case report of a patient presenting very soon in the post-partum period with an unusual form of Takotsubo syndrome without clinical symptoms of cardiac disease and accompanied by HELLP syndrome. The overall dynamics of the changes in troponin I, troponin T and NT-proBNP levels after delivery were generally similar, but the amount of troponin I was much greater than that of troponin T and troponin I was already elevated before delivery. NT-proBNP levels peaked around the same time as the troponins and the peak concentration was within the same range as that of troponin I.

Discussion

Our findings indicate that assaying circulating cardiac biomarkers, especially troponin I and NT-proBNP, may be a useful complement to non-invasive cardiac imaging including transthoracic echocardiography and cardiovascular magnetic resonance imaging, in the diagnosis of Takotsubo syndrome. They illustrate the importance of cardiac biomarkers in assisting diagnosis of this disease.

Stress-Induced Cardiomyopathy—Considerations for Diagnosis and Management during the COVID-19 Pandemic

The novel coronavirus disease 2019 (COVID-19) is associated with several cardiovascular manifestations including myocardial injury, myocarditis, arrhythmia, and pulmonary embolism. Rare cases of stress-induced cardiomyopathy, or takotsubo syndrome have also been reported during the acute infection, and secondary to stress following lockdown and self-isolation. Diagnosis in the setting of the acute infection is challenging since conventional imaging modalities such as transthoracic echocardiography and coronary angiography should be restricted to minimize physician-patient contact until the patients is tested negative for COVID-19. The use of point of care hand-held ultrasound is appropriate for this purpose. The overall course of the disease seems to be similar to takotsubo in the general population. Physicians should be familiar with the clinical presentation, possible complications, and management of takotsubo during COVID-19 outbreak. Here, we review the special considerations in the diagnosis and management of takotsubo syndrome during the current pandemic.

Pathophysiology of Takotsubo Syndrome - a joint scientific statement from the Heart Failure Association Takotsubo Syndrome Study Group and Myocardial Function Working Group of the European Society of Cardiology - Part 1: Overview and the central role for catecholamines and sympathetic nervous system

This is the first part of a scientific statement from the Heart Failure Association of the European Society of Cardiology focused upon the pathophysiology of Takotsubo syndrome and is complimentary to the previous HFA Position Statement on Takotsubo syndrome which focused upon clinical management. In part 1 we provide an overview of the pathophysiology of Takotsubo syndrome and fundamental questions to consider. We then review and discuss the central role of catecholamines and the sympathetic nervous system in the pathophysiology, and the direct effects of high surges in catecholamines upon myocardial biology including β-adrenergic receptor signaling, G protein coupled receptor kinases, cardiomyocyte calcium physiology, myofilament physiology, cardiomyocyte gene expression, myocardial electrophysiology and arrhythmogenicity, myocardial inflammation, metabolism and energetics. The integrated effects upon ventricular haemodynamics are discussed and integrated into the pathophysiological model. This article is protected by copyright. All rights reserved.

Takotsubo Syndrome: Optimizing Care with a Multidisciplinary Approach

Symptoms of takotsubo syndrome (TTS) include acute and transient regional systolic dysfunction of the left ventricle, as well as a variety of wall-motion abnormalities. The clinical features of TTS, including initial symptoms, cardiac biomarkers, and electrocardiogram (ECG) changes, are similar to those of acute coronary syndrome, with the exception that TTS patients typically have no obstructive coronary artery disease. TTS primarily affects elderly women, and emotional or physical stress is a common cause of the disease. Exaggerated sympathetic stimulation associated with dysfunction of the limbic system has also been reported to be related to TTS occurrence. Cancer also induces emotional and physical stress. Therefore, optimization of TTS care should involve cardiac, neurological, psychiatric, and oncological approaches. The first step in optimizing TTS care is to diagnose it by cardiac means. Multimodality imaging, including ECG, echocardiogram, angiography, ventriculography, and cardiac magnetic resonance imaging, is indispensable for diagnosis, therapy management, and the evaluation of prognosis in the acute and chronic phases of TTS. The current cardiac approach during the acute phase is primarily supportive, with the goal of preventing life-threatening complications. As central nervous system diseases frequently trigger TTS, a neurological approach is also required. Appropriate psychiatric medication may reduce the risk of TTS recurrence, as not only psychiatric disorders themselves but also psychiatric medications can be the trigger for TTS. Several conditions are associated with TTS, including the novel coronavirus disease 2019. We present current knowledge of TTS in this review and describe how to optimize TTS care through a multidisciplinary approach.

Sacubitril/valsartan decreases mortality in the rat model of the isoprenaline-induced takotsubo-like syndrome

Aims

Takotsubo syndrome (TTS) is an acute potentially reversible cardiac syndrome characterized by variable regional myocardial akinesia that cannot be attributed to a culprit coronary artery occlusion. TTS is an important differential diagnosis of acute heart failure where brain natriuretic peptides are elevated. Sacubitril/valsartan is a novel and effective pharmacological agent for the treatment of patients with heart failure. Our aim was to explore whether treatment with sacubitril/valsartan could prevent isoprenaline‐induced takotsubo‐like phenotype in rats.

Methods and results

A total number of 186 Sprague–Dawley male rats were randomized to receive pretreatment with water (CONTROL, n = 62), valsartan (VAL, n = 62), or sacubitril/valsartan (SAC/VAL, n = 62) before receiving isoprenaline for induction of TTS. We recorded heart rate and blood pressure invasively. Cardiac morphology and function were evaluated by high‐resolution echocardiography 90 min after the administration of isoprenaline. We documented the survival rate at the time of echocardiography. Compared with the CONTROL group, the SAC/VAL group had less pronounced TTS‐like cardiac dysfunction and lower mortality rate, while the VAL group did not differ. Heart rate and blood pressure were not significantly different between the groups. Analysis of cardiac lipids was performed with mass spectrometry. The VAL and SAC/VAL groups had significantly higher levels of lysophosphatidylcholine (LPC), in particular LPC 18:1 and LPC 16:0.

Conclusions

Pretreatment with sacubitril/valsartan but not with valsartan reduces mortality and attenuates isoprenaline‐induced apical akinesia in the TTS‐like model in rats. Sacubitril/valsartan could be a potential treatment option in patients with TTS in humans.

A systematic review of biomarkers in Takotsubo syndrome: A focus on better understanding the pathophysiology

BACKGROUND

The diagnosis of Takotsubo syndrome is made based on clinical presentation, ECG, biomarker, imaging and coronary angiography. There is a lack of diagnostic biomarkers that can discriminate patients with Takotsubo syndrome from those with acute myocardial infarction (AMI) and provide clinical monitoring and prognostic information in the long-term.

METHODS

A literature search of published Takotsubo syndrome biomarkers from PubMed was performed. All studies that included numerical biomarker data on Takotsubo syndrome was included. Exclusion criteria was any study without an AMI cohort for comparison in the acute phase biomarkers or due to the absence of numerical values. The results were tabulated in table form with results expressed as either mean ± SD or median (interquartile range).

RESULTS

The literature search produced 14 relevant studies that met search criteria. The results showed; high sensitivity Troponin I (3.21 ± 4.4 vs 34.4 ± 37 ng/ml), BNP [972 (578.5-1671.0) pg/L vs 358 (50.5-688.0) pg/L in NSTEMI and vs 381 (106.0-934.0) pg/L in STEMI] and BNP/Troponin I ratio [642 (331.8-1226.5) vs 184.5 (50.5-372.3) pg/ug in NSTEMI and 7.5 (2.0-29.6) pg/ug in STEMI] patients.

DISCUSSION

This study is limited by many studies being retrospective cohort studies. This data shows that acutely troponin is raised in Takotsubo syndrome but not enough to be discriminating from AMI. BNP level is significantly raised in Takotsubo syndrome compared to AMI.

CONCLUSION

Current specificity of acute and chronic biomarkers for Takotsubo syndrome is lacking and further work is needed to address the gap in knowledge.

Diagnosis, Investigation and Management of Patients with Acute and Chronic Myocardial Injury

The application of high-sensitivity cardiac troponins in clinical practice has led to an increase in the recognition of elevated concentrations in patients without myocardial ischaemia. The Fourth Universal Definition of Myocardial Infarction encourages clinicians to classify such patients as having an acute or chronic myocardial injury based on the presence or absence of a rise or a fall in cardiac troponin concentrations. Both conditions may be caused by a variety of cardiac and non-cardiac conditions, and evidence suggests that clinical outcomes are worse than patients with myocardial infarction due to atherosclerotic plaque rupture, with as few as one-third of patients alive at 5 years. Major adverse cardiovascular events are comparable between populations, and up to three-fold higher than healthy individuals. Despite this, no evidence-based strategies exist to guide clinicians in the investigation of non-ischaemic myocardial injury. This review explores the aetiology of myocardial injury and proposes a simple framework to guide clinicians in early assessment to identify those who may benefit from further investigation and treatment for those with cardiovascular disease.

Early Identification of Takotsubo syndrome in the emergency department using point-of-care echocardiography: A case series

Takotsubo syndrome (TS) is an incompletely understood, transient dysfunction of the left ventricle. While acute coronary syndrome must be at the forefront of the differential diagnosis and ruled out appropriately, the possibility of TS can be identified early with point-of-care ultrasonography. The formal diagnostic criteria for TS rely on invasive diagnostic procedures and resolution of symptoms, typically relegating it to a diagnosis of exclusion. However, the acute complications are potentially lethal, and rapid identification is therefore beneficial because these patients can be risk-stratified to higher levels of care. Our case series of three patients, each with early suspected and subsequently confirmed TS, explores how early emergency department ultrasonography can suggest the diagnosis during the emergent workup, and potentially influence disposition decisions, subsequent interventions, and possibly even outcomes.

Current Knowledge and Future Challenges in Takotsubo Syndrome: Part 1-Pathophysiology and Diagnosis

First recognized in 1990, takotsubo syndrome (TTS) constitutes an acute cardiac condition that mimics acute myocardial infarction commonly in the absence of obstructive coronary artery disease; it is characterized by temporary left ventricular dysfunction, regularly in a circumferential apical, midventricular, or basal distribution. Considering its acute clinical presentation, coronary angiography with left ventriculography constitutes the gold standard diagnostic tool to exclude or confirm TTS. Frequently, TTS is related to severe emotional or physical stress and a subsequent increased adrenergic stimulation affecting cardiac function. Beyond clinical presentation, epidemiology, and novel diagnostic biomarkers, this review draws attention to potential pathophysiological mechanisms for the observed reversible myocardial dysfunction such as sympathetic overdrive-mediated multi-vessel epicardial spasms, microvascular dysfunction, the direct toxicity of catecholamines, lipotoxicity, and inflammation. Considering the long-term prognosis, further experimental and clinical research is indispensable to elucidate further pathophysiological mechanisms underlying TTS before randomized control trials with evidence-based therapeutic management can be performed.

A simple procedure in a complex patient: perioperative takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TTC) is a rare but life-threatening condition that is still not completely understood. Characterised by rapidly reversible ventricular dysfunction without any prior coronary artery disease, it can imitate a myocardial infarction and lead to death if not managed appropriately. This report examines a case of intraoperative cardiac arrest in a patient with no previous cardiac disease, and discusses the factors that may have precipitated this event, as well as the ways of distinguishing the cause of the arrest based on clinical course and investigations, eventually leading to a diagnosis of TTC.

Value of Cardiac Biomarkers in the Early Diagnosis of Takotsubo Syndrome

BACKGROUND

Bedside diagnosis between Takotsubo syndrome (TTS) and ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction remains challenging. We sought to determine a cardiac biomarker profile to enable their early distinction.

METHODS

1100 patients (TTS n = 314, STEMI n = 452, NSTEMI n = 334) were enrolled in two centers. Baseline clinical and biological characteristics were compared between groups.

RESULTS

At admission, cut-off values of BNP (B-type natriuretic peptide)/TnI (Troponin I) ratio of 54 and 329 distinguished respectively STEMI from NSTEMI, and NSTEMI from TTS. Best differentiation was obtained by the use of BNP/TnI ratio at peak (cut-of values of 6 and 115 discriminated respectively STEMI from NSTEMI, and NSTEMI from TTS). We developed a score including five parameters (age, gender, history of psychiatric disorders, LVEF, and BNP/TnI ratio at admission) enabling good distinction between TTS and STEMI (77% specificity and 92% sensitivity, AUC 0.93). For the distinction between TTS and NSTEMI, a four variables score (gender, history of psychiatric disorders, LVEF, and BNP at admission) achieved a good diagnostic performance (89% sensitivity, 85% specificity, AUC 0.94).

CONCLUSION

A distinctive cardiac biomarker profile enables at an early stage a differentiation between TTS and ACS. A four (NSTEMI) or five variables score (STEMI) permitted a better discrimination.

Perioperative takotsubo cardiomyopathy: Implications for anesthesiologist

Takotsubo cardiomyopathy (TCM) is characterized by transient ventricular dysfunction in the absence of obstructive coronary artery disease that may be triggered by an acute medical illness or intense physical or emotional stress. TCM is often confused with acute myocardial infarction given the similar electrocardiographic changes, cardiac enzymes, hemodynamic perturbations, and myocardial wall motion abnormalities. In the perioperative setting, the clinical picture may be more confusing because of the effect of anesthesia as well as hemodynamic changes related to the surgery itself. However, awareness of various other diagnostic modalities may enable clinicians to distinguish between the two, more systematically and with greater certainty. Despite the large body of literature, there still seems to be an overall paucity in our understanding of the etiopathogenesis, clinical characteristics, natural history, and management of this syndrome, especially in the perioperative setting. This narrative review seeks to present and synthesize the most recent literature on TCM and to identify gaps in current knowledge which can become the basis for future research.

An Update on Cardiac Magnetic Resonance Imaging in Takotsubo Cardiomyopathy

Purpose of Review

To provide an update on the use of cardiac magnetic resonance imaging in the diagnosis of Takotsubo cardiomyopathy.

Recent Findings

Long-term prognosis of Takotsubo cardiomyopathy may not be as clear-cut as previously thought. Cardiac magnetic resonance imaging not only allows differentiation between reversible and nonreversible changes but has an emerging role in identifying cellular level changes associated with prognostic indicators such as myocardial energetics using 31P-CMR spectroscopy and detection of myocardial inflammation overlying myocardial oedema, using ultrasmall paramagnetic iron oxide particle uptake in macrophages.

Summary

Takotsubo cardiomyopathy is a non-ischemic acute heart failure syndrome. It is commonly triggered by emotional or physical stress and is possibly the strongest psychosomatic interaction seen in medicine. While clinically its presentation mimics a myocardial infarction, the acute imaging characteristics are critical in correctly identifying the disease entity.

The role of inflammation in stress cardiomyopathy

Stress cardiomyopathy (SC) is an increasingly recognized form of acute heart failure, which has been linked to a wide variety of emotional and physical triggers. The pathophysiological mechanisms of the disease remain incompletely understood, however, inflammation has been recently shown to play a pivotal role. This review summarizes the most notable findings of myocardial inflammation, demonstrated from biopsies and cardiac magnetic resonance imaging in humans. In the acute stage macrophage infiltration appears to represent the substrate for myocardial edema, together defining the local myocardial inflammation. This appears to evolve into a low grade systemic chronic inflammation which could explain the protracted clinical course of these patients and raises hope for finding a specific SC cardiac biomarker as well as a therapeutic breakthrough. As a parallel to the human findings the review covers some of the emerging mechanistic insights from experimental models, which, albeit not proven in the human condition, highlight the possible importance in pursuing distinct paths of investigation such as the beta-receptor signaling, aberrations of nitric oxide generation and signaling and the contribution of the vascular endothelium/permeability to edema and inflammation during the acute stage.

MI with Non-obstructive Coronary Artery Presenting with STEMI: A Review of Incidence, Aetiology, Assessment and Treatment

MI with non-obstructive coronary artery (MINOCA) is a condition previously thought to be benign that has recently been shown to have comparable mortality to that of acute coronary syndrome with obstructive coronary disease. The heterogeneity of the underlying aetiology makes the assessment, investigation and treatment of patients with MINOCA challenging. The majority of patients with MINOCA presenting with ST-segment elevation MI generally have an underlying coronary or myocardial cause, predominantly plaque disruption or myocarditis. In order to make the correct diagnosis, in addition to the cause of the presentation, a meticulous and methodical approach is required, with targeted investigations. Stratification of patients to guide investigations that are more likely to provide the diagnosis will allow the correct treatment to be initiated promptly. In this article, the authors review the contemporary incidence, aetiology, recommended assessment and treatment of patients with MINOCA presenting with ST-segment elevation MI.

Biomarkers in patients with Takotsubo cardiomyopathy compared to patients with acute anterior ST-elevation myocardial infarction

Background: Takotsubo cardiomyopathy (TTC) is a syndrome of acute non-coronary heart failure with similar symptoms and electrocardiograms to acute anterior ST-elevation myocardial infarction (STEMI). Little is known about the pathophysiology of TTC. We assessed admission plasma concentrations of biomarkers reflecting neuroendocrine response (copeptin, mid-regional-pro-adrenomedullin, pro-atrial-natriuretic-peptide, soluble thrombomodulin (sTM), syndecan-1) and inflammation (suppression-of-tumorigenicity 2 (ST2), high-sensitive C-reactive-protein) in TTC patients and compared to patients with acute anterior STEMI.Materials and methods: Twenty TTC patients were matched with 40 STEMI patients by age, gender and left ventricular ejection fraction. Blood was sampled upon hospital admission immediately before acute coronary angiography.Results: The groups had similar comorbidities. TTC patients had higher plasma concentrations of sTM: 7.94 (5.89;9.61) vs. 6.42 (5.50;7.82)ng/ml, p = 0.04 and ST2 (53 (32;157) vs. 45 (31;55)ng/ml, p = 0.008) and higher heart rate: 101 ([Formula: see text]33) vs. 76([Formula: see text]14)bpm, p = 0.0001, but lower concentrations of copeptin (10.4 (7.6;39) vs. 92.3 (13;197)pmol/l, p < 0.05) and troponin T (348 (98;759) vs. 1190 (261;4105)ng/l, p = 0.04).Conclusion: TTC patients had higher plasma concentrations of sTM and ST2, higher heart rate and lower copeptin and troponin T concentrations compared to acute anterior STEMI patients. This study contributes to the hypothesis that TTC patients have endothelial cell damage and are hemodynamically more stable than patients with acute anterior STEMI on admission.

An Emerging Cardiovascular Disease: Takotsubo Syndrome

Takotsubo syndrome (TTS) is a recently identified cardiac disease, which is far from being completely known. The aims of this narrative review are to provide a better understanding of the pathophysiological features of TTS and to update clinical findings in order to improve the management of subjects affected by this syndrome (according to the most recent consensus papers issued by the international scientific societies). We based our search on the material obtained via PubMed up to April 2019. The terms used were "Takotsubo Syndrome and Takotsubo cardiomyopathy" in combination with "heart failure, pathophysiology, complications, diagnosis, and treatment." TTS is a reversible form of ventricular dysfunction usually characterized by akinesia of the apex in the absence of obstructive coronary artery disease. In its initial phase, TTS may be indistinguishable from AMI and is usually triggered by a sudden emotional/physical stressor which abruptly increases catecholamine levels. However, the mechanisms by which catecholamines or other unidentified molecules can cause myocardial dysfunction is unknown. In-hospital stay may be hampered by various life-threatening complications, while data on long-term survival remain scarce and unclear. Furthermore, TTS may sometimes recur. We believe that TTS is clearly a much more complex condition than previously thought. Much remains to be discovered about its pathophysiologic mechanisms, the role of the link between the heart and brain and that of triggering factors and gender, and the reasons why this syndrome displays different phenotypes and sometimes recurs. Undoubtedly, preliminary evidence from pathophysiological studies (mainly genetic studies) has shown promising advances. However, prospective randomized clinical trials are still needed in order to identify and to tailor the best medical treatments for TTS patients.

Challenges in high-sensitive troponin assay interpretation for intensive therapy

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

Takotsubo cardiomyopathy: A discussion and case study

BACKGROUND AND PURPOSE

Takotsubo cardiomyopathy (TCM), first reported by Japanese doctors, has gained an overall acknowledgment as an independent malady of international attention. It resembles the presentation of an acute myocardial infarction but lacks ischemic myocardial tissue. The objective of this article is to review the physiology, diagnostics, treatment, and complications of TCM and report a case study of a patient who developed TCM.

METHODS

Observation through direct patient care allowed for data collection of this unique medical phenomenon. Supporting information was obtained via investigation of scholarly articles on TCM over the past 10 years.

CONCLUSIONS

Although TCM is usually transient, it is important to quickly differentiate TCM from other more serious medical conditions, such as myocardial infarction, pulmonary embolism, and pheochromocytoma. Typical diagnostic workup includes electrocardiography, cardiac biomarkers, and echocardiography or coronary angiography. Complications include cardiogenic shock, left ventricular wall rupture, and life-threatening arrhythmias.

IMPLICATIONS FOR PRACTICE

The advanced practice nurse (APN) is instrumental in differentiating between TCM versus acute myocardial infarction, heart failure, pulmonary edema, dynamic outflow obstruction, and cardiogenic shock. Because of these possible acute and critical presentations, prompt recognition and intervention for patients with TCM are priorities for nurse practitioners.

Clinical Outcome of Takotsubo Cardiomyopathy Diagnosed With or Without Coronary Angiography

Takotsubo cardiomyopathy (TC) is definitively diagnosed following the exclusion of acute coronary syndrome. We aimed to examine the rate of coronary angiography in patients diagnosed with TC and also the outcome of patients with TC diagnosed with or without coronary angiography. We analyzed the National Inpatient Sample database from 2010 to 2014 and identified patients hospitalized with a primary diagnosis of TC. We compared in-hospital mortality between patients who underwent coronary angiography and those who did not. We also evaluated the association between coronary angiography and in-hospital mortality using a propensity score–adjusted multivariable analysis. Among 22 818 patients diagnosed with TC, 87.4% underwent coronary angiography and 12.6% did not. Patients who did not undergo coronary angiography had a higher in-hospital mortality than those who did (3.0% vs 0.9%; P < .001). Increased mortality in patients who did not undergo coronary angiogram was observed in both male (8.0% vs 2.8%; P = .03) and female patients (2.6% vs 0.7%; P < .001) and in patients 61 to 80 years old and ≥81 years old, but not in patients ≤60 years old. Multivariable analysis demonstrated that the lack of coronary angiography was independently associated with higher in-hospital mortality (adjusted odds ratio: 2.92; 95% confidence interval: 1.52-5.65; P = .001).

Prognostic value of N-Terminal Pro-B-Type Natriuretic Peptide in Takotsubo syndrome

BACKGROUND

Takotsubo syndrome (TTS), a form of acute transient heart failure, has been associated with severe complications and considerable mortality rates. N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) might serve as a marker to identify high-risk patients but has not yet been investigated regarding prognostic implications in TTS. Aim of this study was to determine the short- and long-term prognostic utility of NT-proBNP in patients with TTS.

METHODS

The predictive value of admission NT-proBNP was assessed in an international, multicenter study including 177 consecutive TTS patients. Predefined endpoints were 30-day major adverse cardiac events (MACE) consisting of all-cause death, cardiogenic shock, and pulmonary edema as well as long-term mortality in median 2.3 years after the acute event.

RESULTS

Stratification according to median admission NT-proBNP (4511 pg/ml) resulted in significantly higher 30-day MACE [22.5 versus 9.1%; odds ratio (OR) 2.90, 95% confidence interval (CI) 1.20-6.99 p = 0.015] and long-term mortality rates [16.3 versus 9.4%; hazard ratio (HR) 2.72, 95% CI 1.13-6.56 p = 0.021] in patients > median. The best admission NT-proBNP cutoffs to predict 30-day MACE and long-term mortality were determined at 5560 and 8178 pg/ml respectively, with subsequent improved risk stratification for short-term MACE (OR 3.61, 95% CI 1.49-8.72; p = 0.003) and long-term mortality (HR 4.40; 95% CI 1.85-10.44, p < 0.001). Multivariate regression analysis identified admission NT-proBNP as an independent predictor of 30-day MACE (p < 0.001) and long-term mortality (p = 0.012).

CONCLUSIONS

Admission NT-proBNP is an independent predictor for short- and long-term adverse events in TTS patients and, therefore, a useful marker for risk stratification immediately at presentation.

Novel Understanding of Takotsubo Syndrome

Takotsubo cardiomyopathy is described as a transient reversible cardiomyopathy which typically occurs in older women after emotional or physical stress. This cardiomyopathy is also recognized as a "syndrome" because it develops in conjunction with various diseases. Since the clinical presentation of takotsubo syndrome (TTS) is similar to acute coronary syndrome (ACS), TTS should be distinguished from ischemic heart disease. Although the pathophysiology of TTS has not well been established, a number of its specific features have been suggested. The predictor of mortality in TTS is still unknown. In this review article, we describe a series of treatment decisions in TTS.

Role of echocardiography for takotsubo cardiomyopathy: clinical and prognostic implications

Takotsubo cardiomyopathy (TTC) is newly-described secondary cardiomyopathy characterized by transient left ventricular (LV) dysfunction, which is increasingly recognized in the field of cardiology. TTC occurs in approximately 2% of the patients with acute coronary syndrome. Its onset is rare; however, its specific features play a crucial role in diagnosing the chest pain in clinical practice. TTC has generally favorable outcome with rapid recovery of LV function; however, an increasing evidence suggests that it should be regarded as a more serious acute cardiac disorder with a variety of complications. Owing to its widespread availability, even in emergency settings, transthoracic echocardiography plays a key role in the diagnostic assessment of TTC and contributes to an increased number of disease detection and incidence reports in contemporary clinical practice. This review focuses on the role of echocardiography in understanding the clinical prognostic implications in patients with TTC.

Takotsubo cardiomyopathy: Pathophysiology and role of cardiac biomarkers in differential diagnosis

Takotsubo cardiomyopathy (TC) is characterized by reversible ventricular dysfunction, not limited to the distribution of an epicardial coronary artery. A disease primarily afflicting post-menopausal women, it is frequently mistaken for acute anterior wall myocardial infarction. Alternatively called Stress Cardiomyopathy, physical or emotional triggers are identified in only three fourths of TC patients. Long considered a benign condition, recent findings suggest poor short term prognosis similar to acute coronary syndrome (ACS). Despite the widely recognized pathophysiological role of catecholamine excess, its diagnostic role is uncertain. TC is suspected based on typical wall motion abnormalities in ventriculogram or echocardiogram. Several additional electrocardiographic, laboratory and imaging parameters have been studied with the goal of clinical diagnosis of TC. While several clinical clues differentiate it from ACS, a clinical diagnosis is often elusive leading to avoidable cardiac catheterizations. Natriuretic peptides (NPs), a family of peptide hormones released primarily in response to myocardial stretch, play a significant role in pathophysiology, diagnosis as well as treatment of congestive heart failure. TC with its prominent ventricular dysfunction is associated with a significant elevation of NPs. NPs are elevated in ACS as well but the degree of elevation is typically lesser than in TC. Markers of myocardial injury such as troponin are usually elevated to a higher degree in ACS than in TC. This differential elevation of NPs and markers of myocardial injury may play a role in early clinical recognition of TC.

Pathophysiology of Takotsubo Syndrome

Originally described by Japanese authors in the 1990s, Takotsubo syndrome (TTS) generally presents as an acute myocardial infarction characterized by severe left ventricular dysfunction. TTS, however, differs from an acute coronary syndrome because patients have generally a normal coronary angiogram and left ventricular dysfunction, which extends beyond the territory subtended by a single coronary artery and recovers within days or weeks. The prognosis was initially thought to be benign, but subsequent studies have demonstrated that both short-term mortality and long-term mortality are higher than previously recognized. Indeed, mortality reported during the acute phase in hospitalized patients is ≈4% to 5%, a figure comparable to that of ST-segment-elevation myocardial infarction in the era of primary percutaneous coronary interventions. Despite extensive research, the cause and pathogenesis of TTS remain incompletely understood. The aim of the present review is to discuss the pathophysiology of TTS with particular emphasis on the role of the central and autonomic nervous systems. Different emotional or psychological stressors have been identified to precede the onset of TTS. The anatomic structures that mediate the stress response are found in both the central and autonomic nervous systems. Acute stressors induce brain activation, increasing bioavailability of cortisol and catecholamine. Both circulating epinephrine and norepinephrine released from adrenal medullary chromaffin cells and norepinephrine released locally from sympathetic nerve terminals are significantly increased in the acute phase of TTS. This catecholamine surge leads, through multiple mechanisms, that is, direct catecholamine toxicity, adrenoceptor-mediated damage, epicardial and microvascular coronary vasoconstriction and/or spasm, and increased cardiac workload, to myocardial damage, which has a functional counterpart of transient apical left ventricular ballooning. The relative preponderance among postmenopausal women suggests that estrogen deprivation may play a facilitating role, probably mediated by endothelial dysfunction. Despite the substantial improvement in our understanding of the pathophysiology of TTS, a number of knowledge gaps remain.

Acute stress-induced (takotsubo) cardiomyopathy

Acute stress-induced (takotsubo) cardiomyopathy has a dramatic clinical presentation, mimicking an acute myocardial infarction and is triggered by intense emotional or physical stress. In this paper, we review the current state of knowledge of the mechanistic physiology underlying the left ventricular ballooning. The pathophysiology of the recovery from this acute heart failure syndrome is presented. The short-term and long-term outlook puts this new syndrome on a different perspective compared with recently held views. Current knowledge on susceptibility and predisposition already define distinctive characteristics of patients with takotsubo compared with myocardial infarction. Gaps in knowledge and future directions of research are identified in order to best direct efforts for identifying specific therapies for this condition, in the acute setting, to mitigate postacute symptoms or to prevent recurrences, none of which exist.

Ratio of high-sensitivity troponin to creatine kinase-MB in takotsubo syndrome

BACKGROUND

Takotsubo syndrome (TT) and myocardial infarction (MI) share numerous similarities in clinical presentation, ECG modifications and biomarker elevation. We sought to determine whether the ratio of high-sensitivity cardiac troponin T (hs-TnT) to the myocardial fraction of creatine kinase (CKMB) could be a potent discriminator between TT and MI patients.

METHODS

We separately present analysis of data from retrospective files and prospectively recruited patients presenting with TT (35 retrospective and 42 prospective), NSTEMI (48 retrospective and 75 prospective) and STEMI (20 retrospective and 39 prospective). We compared ratios of hs-TnT to CKMB on admission to the hospital between TT, NSTEMI and STEMI patients. Receiver operating characteristic (ROC) curves were analysed to determine optimal cut-off values.

RESULTS

On admission, hs-TnT/CKMB ratio was significantly higher in TT patients than in NSTEMI and STEMI patients in both the retrospective phase (median and interquartile range, TT 0.024 [0.018-0.047] vs NSTEMI 0.009 [0.006-0.022], p<0.0001; TT vs STEMI 0.011 [0.006-0.016], p=0.0002) and the prospective cohort (median and interquartile range, TT 0.032 [0.018-0.040] vs NSTEMI 0.009 [0.006-0.015], p<0.0001; TT vs STEMI 0.009 [0.005-0.017], p<0.0001). A cut-off hs-TnT/CKMB ratio of 0.015 distinguished TT from MI with a sensitivity of 85.7% and a specificity of 67.6% (AUC 0.796; 95%CI: 0.71-0.89) in the retrospective phase. In the prospective phase, a ratio of 0.017 distinguished TT from MI with a sensitivity of 83.3% and a specificity of 78.1% (AUC 0.88; 95%CI: 0.83-0.94).

CONCLUSION

hs-TnT/CKMB ratio is a novel, readily available parameter that could be used alongside clinical risk scores, other biomarkers and ECG findings to discriminate between TT and MI.

Simple markers can distinguish Takotsubo cardiomyopathy from ST segment elevation myocardial infarction

BACKGROUND

Takotsubo cardiomyopathy (TTC) is a clinical condition mimicking acute myocardial infarction. A specific biomarker for TTC screening is required, but until now, no single biomarker has been established for the early diagnosis of TTC and differentiation from ST-segment elevation myocardial infarction (STEMI). In our study we focused on the simple markers that are available in every hospital.

METHODS

In 66 consecutive patients (pts) who were hospitalized with TTC and 66 pts with STEMI, cardiac biomarkers, such as NT-proBNP, TnI, CK and CKMB mass were determined during 12h from admission and compared with demographic, clinical and echocardiographic findings.

RESULTS

The concentration of NTproBNP was greater in pts with TTC than STEMI (4702pg/ml vs 2138pg/ml). The concentration of TnI and CKMB mass was greater in the STEMI group than in the TTC group (TnI: 2.1ng/ml and CK MB mass: 9.5ng/ml in pts with TTC vs TnI: 19ng/ml and CK MB mass: 73.3ng/ml in pts with STEMI). The NTproBNP/TnI ratio and NTproBNP/CKMB mass ratio were, respectively, 2235.2 and 678.2 in pts with TTC and 81.6 and 27.5 in pts with STEMI (p<0.001). Moreover, the NTproBNP/EF ratio was also statistically significant (110.4 in TTC group and 39.4 in STEMI group).

CONCLUSIONS

NTproBNP/TnI, NTproBNP/CKMB mass and NTproBNP/EF ratios can distinguish TTC from STEMI at an early stadium. The most accurate marker is the NTproBNP/TnI ratio.

Editor's Choice-Biomarkers of acute cardiovascular and pulmonary diseases

Acute cardiothoracic and respiratory diseases frequently remain a challenge to diagnose and differentiate in the emergency setting. The main diseases that manifest with chest pain include ischaemic heart disease, myocarditis, acute pericarditis, aortic dissection/rupture and pulmonary embolism (PE). Diseases that primarily present with dyspnoea include heart failure (HF), acute respiratory distress syndrome (ARDS), pneumonia, asthma exacerbations and chronic obstructive pulmonary disease. Pre-test probabilities of clinical findings play a vital part in diagnostic decisions, and the use of a Bayesian approach to these greatly improves the ability to stratify patients more accurately. However, blood tests (biomarkers) are increasingly used to assist in rapid decision-making in the emergency setting in combination with imaging methods such as chest radiograph, ultrasound and increasingly computed tomography, as well as physiological tests such as the electrocardiogram in addition to physical examination. Specific tests for ischaemic heart disease and myocarditis (cardiac troponins), HF (B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP)), aortic dissection (smooth muscle markers) and PE (D-dimer) have been developed. Surfactant protein-D and interleukin-8 have been developed for ARDS. Additionally, circulating microRNAs have emerged as promising biomarker candidates in cardiovascular disease. With this increasing array of biochemical markers to aid in the diagnosis of chest diseases presenting with chest pain and dyspnoea, we herein review the clinical usefulness of these markers, in particular in differentiating cardiac from pulmonary diseases. A symptom-oriented assessment as necessary for use in the critical setting is described in addition to discussion of individual biomarkers.