Apicobasal gradient of left ventricular myocardial edema underlies transient T-wave inversion and QT interval prolongation (Wellens' ECG pattern) in Tako-Tsubo cardiomyopathy

Left ventricular outflow tract obstruction/hypertrophic cardiomyopathy/takotsubo syndrome: A new hypothesis of takotsubo syndrome pathophysiology

The pathophysiology of TTS is still elusive. This viewpoint proposes that TTS is an acute coronary syndrome, engendered by an ASNS/catecholamine-induced LVOTO, which results in an enhanced wall stress and afterload-based supply/demand mismatch, culminating in a segmental myocardial ischemic injury state, in susceptible individuals. Such individuals are felt to be particularly women with chronic hypertension, known or latent HCM, or non-HCM segmental myocardial hypertrophy, and certain structural abnormalities involving the LV and the MV apparatus. Recommendations are provided to explore further this hypothesis, while maintaining our focus on all other advanced TTS pathophysiology hypotheses for all patients, or those who do not experience LVOTO, men, the young, and patients with reverse, mid-ventricular, or right ventricular TTS, in whom more prolonged hyperadrenergic stimulation and/or larger amounts of blood-ridden catecholamines, segmental particularities of cardiac innervation and/or density of α-, and β-adrenergic receptors, pheochromocytoma, neurological chronic or acute comorbidities/catastrophies, coronary epicardial/microvascular vasospasm, and CMD.

Comparison of electrographic changes, clinical features and outcomes in different variants of Takotsubo syndrome

BACKGROUND

Dysfunction of the left ventricular (LV) apex (apical variant) is the most common form in Takotsubo syndrome (TS). Several less common non-apical variants have been described - mid-ventricular, basal and focal. We hypothesised that the clinical presentation, and electrocardiographic (ECG) findings may vary between apical and non-apical TS.

METHODS

We prospectively identified 194 consecutive patients with TS presenting to Middlemore Hospital, Auckland and obtained clinical, echocardiography, coronary angiography, and long-term follow-up data. ECGs at admission and Day 1 were compared.

RESULTS

Of 194 patients with TS, 168 (86.6%) had apical TS, and 26 (13.4%) non-apical TS (11 mid-ventricular TS, 5 basal TS, 10 focal TS). Apical TS patients had more significant LV systolic impairment (p = 0.001) and longer length of stay (p = 0.001). The extent of T-wave inversion (TWI) was similar for both groups on admission (p = 0.88). By Day 1 the extent of TWI was greater in apical TS group (median number of leads 5 vs. 1, p = 0.02). The change in QTc interval between admission and Day 1 was greater in apical TS group (29.7 ms vs. 2.77 ms, p < 0.001). Composite in-hospital complication rate was similar for both groups (13.7% vs. 15.4%, p = 0.77).

CONCLUSIONS

Compared with non-apical variants, apical TS patients develop more extensive TWI and greater QT prolongation on ECG, and more significant LV systolic impairment, but in-hospital complications were similar. Clinicians should be aware that there is a sub-group of TS patients who have non-apical regional wall motion abnormalities and who don't develop ECG changes typical of the more common apical variant.

Takotsubo pathophysiology and complications: what we know and what we do not know

Takotsubo cardiomyopathy or stress cardiomyopathy (SCM), was first described in 1990 and initially, it was thought to be only associated with short-term complications and mortality with a benign long-term prognosis comparable to a healthy population. However recent investigations have proven otherwise and have shown SCM patients might have comparable long-term morbidity and mortality to ST-elevation myocardial infarction (STEMI) patients. Many emotional, or physical stressors can trigger SCM, and have been able to describe an interplay of neurohormonal and inflammatory mechanisms as the pathophysiology of this disease. Additionally, given the significantly higher prevalence of SCM in post-menopausal women, estrogen levels have been thought to play a role in the pathogenesis of this disease. Furthermore, there is an elusive disparity in prognosis depending upon different triggers. Currently, many questions remain unanswered regarding the long-term management of these patients to reduce morbidity, mortality, and improve quality of life, such as the need for long-term anticoagulation. In this paper, we review the findings of most recent published investigations regarding etiologies, pathophysiology, diagnostic criteria, prognosis, short-term and in more detail, long-term complications of SCM. Finally, we will discuss what future research is needed to learn more about this disease to improve the long-term prognosis, even though as of now, data for long-term management is still lacking.

Comments on "QT interval prolongation in Takotsubo syndrome: a frightening feature with no major prognostic impact"

Dear Editor, Pinho et al. reported on the acquired corrected QT-interval (QTc) prolongation in a retrospective analysis of 113 patients (aged 67.6±11.7, 94.7% female)...

Serial electrocardiograms at follow-up for early detection of transplanted heart rejection: A viewpoint

This viewpoint proposed that serial electrocardiograms (ECG) could be used to monitor for heart transplantation (HT) rejection, based on the expected attenuation of the amplitude of ECG QRS complexes (attQRS) engendered by the rejection-induced decrease in electrical resistance due to the underlying myocardial edema (ME). Previous work in humans has shown attQRS in the setting of a diverse array of edematous states, affecting the myocardium (i.e, ME) and the body volume conductor "enveloping" the heart. Also, animal and human experience has revealed low electrical resistance during mild/moderate HT rejection. Studies with serial correlations of endomyocardial biopsy (EMB), echocardiography, cardiac magnetic resonance imaging, and ECG are recommended, which will merely require recording of an ECG, when EMB and imaging studies are carried out for monitoring of post-HT rejection.

Incidence, management, and prognostic impact of arrhythmias in patients with Takotsubo syndrome: a nationwide retrospective cohort study

AIMS

Arrhythmia is a major complication of Takotsubo syndrome (TTS). However, its incidence, management, and prognostic impact remain to be elucidated in a large cohort.

METHODS AND RESULTS

We retrospectively identified 16 713 patients hospitalized for TTS between July 2010 and March 2021 from the Japanese Diagnosis Procedure Combination database. Serious arrhythmias were defined as ventricular tachycardia/fibrillation (VT/VF), 2nd-/3rd-degree atrioventricular block (AVB), sick sinus syndrome (SSS), or unspecified arrhythmias requiring device treatment. Patient characteristics and outcomes were compared based on the occurrence of serious arrhythmias. The overall incidence proportion of serious arrhythmias was 6.2% (n = 1036; 449 VT/VF, 283 2nd-/3rd-degree AVB, 133 SSS, 55 multiple arrhythmias, 116 others), which remained stable over 11 years. The arrhythmia group was younger, more often male, and exhibited greater impairment in activities of daily living (ADLs) and consciousness than the non-arrhythmia group. Although crude in-hospital mortality was higher in the arrhythmia group (9.6% vs. 5.0%, P < 0.001), the significant association between arrhythmias and mortality disappeared after adjustment for confounders (odds ratio = 1.15, 95% confidence interval = 0.90-1.49). Meanwhile, age, sex, ADLs, consciousness level, and Charlson comorbidity index were significantly associated with mortality. In the arrhythmia group, 254 (24.5%) patients received pacemakers (18.4%) or defibrillators (6.1%), which were implanted at a median of 8 and 19 days after admission, respectively.

CONCLUSION

Arrhythmias are not uncommon in TTS. Patients' background characteristics, rather than arrhythmia itself, may be associated with in-hospital mortality. Given the reversibility of cardiac dysfunction in TTS, there may be unnecessary device implantations for arrhythmias occurring as sequelae to TTS, warranting further investigations.

Cardiac Magnetic Resonance-Detected Acute Myocardial Edema as Predictor of Favourable Prognosis: A Comprehensive Review

Acute myocardial edema (AME) is increased water content in the myocardium and represents the first and transient pathophysiological response to an acute myocardial injury. In-vivo and non-invasive evaluation is feasible with cardiac magnetic resonance (CMR), which is a powerful imaging technique capable of tissue characterization. In the clinical setting, early demonstration of AME has a recognized diagnostic value for acute coronary syndromes and acute myocarditis, although its prognostic value is not well established. This article provides a comprehensive narrative review on the clinical meaning of AME in heart diseases. In particular, the available evidence of a possible favourable prognostic value in several clinical scenarios is addressed.

Shark Sighting in an Electrocardiogram

This case report describes a patient in their late 50s with elevated high-sensitivity cardiac troponin and a medical history of poorly controlled diabetes and cocaine, cannabis, and tobacco use.

Prognostic value of the Tpeak-Tend interval for in-hospital subacute ventricular arrhythmias in tako-tsubo syndrome

INTRODUCTION AND OBJECTIVES

The clinical value of electrocardiogram (ECG) repolarization parameters associated with ventricular arrhythmias (VAs) in tako-tsubo syndrome is still under debate. We aimed to evaluate ECG predictors of subacute VAs, defined as those occurring after the first 48hours from admission.

METHODS

This single-center observational study enrolled patients admitted to the cardiology department between 2012 and 2018 with a confirmed diagnosis of tako-tsubo syndrome. Data collection included a 12-lead ECG on admission and at 48hours, continuous telemetry monitoring, blood testing, transthoracic echocardiography, and coronary angiography during hospitalization. VAs events were defined as: premature ventricular contractions ≥ 2000 within a 24-hour window of telemetry monitoring, ventricular fibrillation, sustained ventricular tachycardia (VT), polymorphic VT, and non-sustained VT.

RESULTS

A total of 87 patients (age 72±12 years) were enrolled. During a median of 8 days of hospitalization, subacute VAs were documented in 22 patients (25%) after a median of 91hours from admission. Subacute VAs were associated with an increase in mortality during hospitalization (P=.030). The corrected global (mean of the 12-lead ECG values) Tpeak-Tend interval at 48hours from admission was an independent predictor of subacute VAs and was statistically superior to the standard corrected QT interval (Z test, P=.040). A cut-off of 108 msec for the corrected global Tpeak-Tend yielded a 71% sensitivity and 72% specificity for subacute VAs.

CONCLUSIONS

In patients with tako-tsubo syndrome, subacute VAs are associated with repolarization alterations that can be identified on conventional ECG using the Tpeak-Tend interval.

Arrhythmias and Their Electrophysiological Mechanisms in Takotsubo Syndrome: A Narrative Review

BACKGROUND

Takotsubo syndrome (TTS), an acute and usually reversible condition, is associated with both tachy- and bradyarrhythmias. Such arrhythmias can be life-threatening, e.g. ventricular tachycardia and fibrillation, and associated with cardiac arrest. Others, such as atrioventricular block, persist and require long-term device therapy. In this narrative review, we aim to provide a summary of the current literature on arrhythmias in TTS and their clinical sequelae.

METHODS

PubMed and Medline databases were searched with various permutations of TTS, arrhythmias and beta-adrenoceptors. After application of exclusion criteria and review, 84 articles were included.

RESULTS

Although there are no specific electrocardiograph (ECG) findings in TTS to differentiate it from ST-elevation myocardial infarction, suggestive patterns include small QRS amplitude, ST segment elevation without reciprocal ST depression and prolonged QT interval. Atrial tachyarrhythmias (incidence of 5-15%) are associated with a more unwell patient cohort. Ventricular arrhythmias (incidence 4-14%) are often associated with prolonged QT interval and are a cause of sudden death in TTS. Bradyarrhythmias are less common (incidence 1.3-2.5%), but have been reported with TTS, and usually persist beyond the acute phase.

CONCLUSIONS

Takotsubo syndrome, though considered primarily a disease of the myocardium, carries multiple arrhythmic manifestations that affect short- and long-term prognosis. The management of such arrhythmias represents a constantly evolving area of research.

Typical dynamic electrocardiographic changes in Takotsubo syndrome

AIMS

Negative T waves and QTc prolongation often occur in patients with Takotsubo syndrome. Description of typical electrocardiographic changes could be a diagnosis element of this syndrome. This study aimed to clarify on the one hand the more preciously possible the typical electrocardiographic changes, and on the other hand, the timing of occurrence of these abnormalities compared to the trigger occurrence, the symptoms onset and the hospital admission.

METHODS AND RESULTS

We studied ECGs at admission of 59 patients with Takotsubo syndrome, a 'reference' ECG and each one available during the first five days after admission.We observed significant changes on the pathological ECG compared to reference ECG: the mean number of leads with negative T waves (7.4 ± 1.9 mm vs 2.1 ± 1.4 mm, p < 0.0001), the highest value of negative T wave deflection among all the leads (-6.2 ± 4mm vs -1.4 ± 0.9 mm, p < 0.0001), the sum of all negative T waves (-27 ± 1.7 mm vs -2.8 ± 3.6 mm, p < 0.0001 and a QTc max and QTc mean prolongation (539 ± 63ms vs 457 ± 42ms, p < 0.0001 and 491 ± 52ms vs 421 ± 33ms, p < 0.0001 respectively). We also demonstrated that T waves were significantly more positive in pathological ECG in aVR and V1 compared to the reference one (mean value of T waves respectively of 1.8 ± 1.8 vs -1 ± 1.3, p < 0.0001 and 0.7 ± 1.6 vs 0.004 ± 1.2, p = 0.008).

CONCLUSION

The QTc prolongation, the profound negative T waves except in aVR and V1 occurring the first two days after admission are electrocardiographic changes typically of Takotsubo syndrome.

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.

Dynamic Trend of Myocardial Edema in Takotsubo Syndrome: A Serial Cardiac Magnetic Resonance Study

Background: The wall motion abnormalities of the left ventricle (LV) in takotsubo syndrome (TTS) are known to be transient and completely recover within a few weeks. However, there is little information about the relationship between functional recovery and tissue characteristics. The aim of this study was to investigate the recovery process of TTS using cardiovascular magnetic resonance (CMR). Methods: Consecutive patients with TTS were prospectively enrolled. We performed serial CMR in the acute phase (<72 h after admission), the subacute phase (7–10 days after admission) and the chronic phase (3 months later). To assess the degree of myocardial edema quantitatively, we evaluated the signal intensity of myocardium on T2-weighted images and calculated the signal intensity ratio compared with the skeletal muscle. Results: Fifteen patients with TTS were enrolled. CMR demonstrated reduced LV ejection fraction in the acute phase, and it recovered almost completely by the subacute phase. On the other hand, severe myocardial edema was still observed in the subacute phase, associated with increased LV mass. The highest signal intensity ratio in the subacute phase was correlated with the maximum voltage of negative T wave on electrocardiogram (r = 0.57, p = 0.03). Conclusions: In patients with TTS, myocardial edema associated with increased LV mass still remained in the subacute phase despite functional recovery of the LV. Electrocardiogram may be useful to assess the degree of myocardial edema in the subacute phase. Our study suggests that myocardial ischemia might have a central role in developing TTS.

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.

Cardiovascular Magnetic Resonance (CMR) for the Evaluation of Myocardial Infarction in Patients with Non-obstructive Coronary Artery Disease (MINOCA)

Purpose of Review

Myocardial infarction in the absence of coronary artery disease is caused by a variety of clinical conditions, so it is important to detect the specific causes in order to perform a better prognostic stratification of these patients. The aim of this review is to summarize the most important findings that established the role of CMR (cardiovascular magnetic resonance) to detect the MINOCA (myocardial infarction with non-obstructive arteries) patients and the importance to differentiate them from myocardial infarction patients.

Recent Findings

The role of CMR is crucial to diagnose the principal diseases involved in MINOCA, as demonstrated. The several MR sequences used in all the MINOCA patients showed different results for all the different causes of MINOCA and, surely, high-resolution MR with gadolinium enhancement has been considered the best method to differentiate the transmural lesions.

Summary

Another fundamental aspect to be considered is the experience of CMR radiologists, which represent the most important element for the right diagnosis of MINOCA. Surely, in the future, CMR will be the most important technique of choice for MINOCA patients, playing a key role in their management.

Transient deep and giant negative T waves in dogs with myocardial injury

INTRODUCTION

Although transient deep and giant negative T waves (NTWs) may develop during myocardial injury (MI) in humans, no data exist on this repolarization abnormality in canine MI. Therefore, this study aimed to describe the occurrence of transient deep/giant NTWs in dogs with MI.

ANIMALS, MATERIALS AND METHODS

Medical records were retrospectively searched to identify dogs with MI and transient deep/giant NTWs. Signalment, history, and selected diagnostic test results were reviewed. Data analysis was descriptive.

RESULTS

Six cases were diagnosed with MI associated with deep (n = 1) and giant (n = 5) transient NTWs. Myocardial injury was classified as acute in all cases and was due to snake envenomation (n = 3), sepsis (n = 2), and systemic inflammatory response syndrome (n = 1). At the time of deep/giant NTWs identification, all dogs had elevated cardiac troponin I and ≥1 echocardiographic abnormality of the left ventricular structure and/or function. Moreover, all dogs with giant NTWs had prolonged QT intervals. After the MI resolution, T-wave polarity and QT-interval duration became normalized in all dogs. Moreover, left ventricular morphological and functional parameters were completely normalized in four dogs. In contrast, ventricular echogenicity remained heterogeneous in two dogs, despite otherwise normalized ventricular parameters. Five dogs were still alive at the conclusion of the study.

CONCLUSIONS

Transient deep/giant NTWs may develop in dogs with acute MI and T-wave polarity changes seem to occur synchronously with the evolution of myocardial damage. Moreover, transient deep/giant NTWs seem associated with a favorable prognosis in canine MI.

Clinical Value and Time Course of Pericoronary Fat Inflammation in Patients with Angiographically Nonobstructive Coronaries: A Preliminary Report

The introduction of high-sensitivity cardiac troponin allowed identifying a proportion of subjects with chest pain and electrocardiographic changes suggestive of myocardial infarction showing <50% coronary artery stenosis. PFAI is a coronary CT marker proved to predict outcome in ischemic heart disease. Based on CMR findings, patients were divided into myocarditis (n = 15), MINOCA (n = 14) and TTS (n = 9) groups. The aim was to estimate the value of pFAI in these groups compared to 12 controls. To evaluate the coronary inflammation “time course,” 20 patients underwent CMR and coronary CT scan within 8 days from the onset, the others within 60 days. There were higher values of pFAI in myocarditis (−86.45 HU), MINOCA (−84.63 HU) and TTS (−84.79 HU) compared to controls (−96.02 HU; p = 0.0077). Among patients who underwent CT within 8 days from onset, the MINOCA had a significantly higher pFAI value (−76.91 HU) compared to the control group (−96.02 HU; p = 0.0001). In the group that underwent CT later than 8 days, elevated pFAI values persisted only in the myocarditis and TTS groups, and there was no difference between MINOCA and controls. Our study shows that in patients with a diagnosis of MINOCA, there is acute coronary inflammation, which is more evident within one week from the acute event but tends to disappear with time.

Electrocardiographic Characteristics and Associated Outcomes in Patients with Takotsubo Syndrome. Insights from the RETAKO Registry

Electrocardiographic disturbances in Takotsubo syndrome have been previously partially described but their consequences remain mostly unknown. Our aim was to describe the prevalence and prognostic significance of different electrocardiographic features in patients with Takotsubo syndrome. Our data come from the Spanish multicenter REgistry of TAKOtsubo syndrome (RETAKO). All patients with an available 12-lead surface electrocardiogram at admission and 48 hours post-admission were included. A total of 246 patients were studied, mean age was 71.3 ± 11.5 and 215 (87.4%) were women. ST-segment elevation was seen in 143 patients (59.1%) and was present in ≥2 wall leads in 97 (39.8%). Exclusive elevation in inferior leads was infrequent (5% - 2.0%). After 48 hours, 198 patients (88.0%) developed negative T waves in a median of 8 leads with a mean amplitude of 0.7 ± 0.5 mV and 137 (60.9%) had pathological Q waves. The mean corrected QT interval was 520 ± 72 ms. Corrected QT interval was independently associated with the primary endpoint of all-cause death and nonfatal cardiovascular events (P = 0.002) and all-cause death (P = 0.008). A higher heart rate at admission was an independent predictor of the primary endpoint (P = 0.001) and of acute pulmonary edema (P = 0.04). ST-segment elevation with reciprocal depression was an independent predictor of all-cause death (P = 0.04). Absence of ST-segment deviation was a protective factor (P = 0.005) for the primary endpoint. Tachyarrhythmias were independently associated with cardiogenic shock (P< 0.001). Takotsubo syndrome patients present with distinct electrocardiographic features. Prolonged corrected QT interval, tachyarrhythmias, heart rate at admission, and more extensive repolarization alterations are associated with poor outcomes.

Ventricular arrhythmias in Takotsubo Syndrome: incidence, predictors and clinical outcomes

AIMS

To investigate predictors of the occurrence of subacute ventricular arrhythmias (VAs), defined as any VAs presenting after 48 h from admission in patients with Takotsubo Syndrome (TTS), and to evaluate the related in-hospital mortality.

METHODS

This is a retrospective single-center study enrolling patients admitted between 2012 and 2017 with TTS according to International Takotsubo diagnostic criteria. Data collection included ECG on admission and at 48 h, telemetry monitoring and transthoracic echocardiogram.

RESULTS

We enrolled 93 patients; during in-hospital stay (mean 14 ± 16 days) subacute VAs occurred in 25% of patients (VAs group). Life-threatening VAs occurred in 6% of patients (3 sustained ventricular tachycardia, 1 torsade de pointes, 1 ventricular fibrillation) and not life-threatening VAs in 19% (6 non-sustained ventricular tachycardia and 12 premature ventricular contractions > 2000 in 24 h). Mortality was higher in the VAs than in the non-VAs group (P = 0.03), without differences in terms of life-threatening and not life-threatening subacute VAs (P = 0.65) and VAs on admission (P = 0.25). Logistic regression identified the following independent predictors of subacute VAs occurrence: VAs on admission {odds ratio [OR] 22.5 (3.9-131.8), P = 0.001]}, New York Heart Association (NYHA) class III-IV on admission [OR 6.7 (1.3- 34.0), P = 0.021] and QTc at 48 h [OR 1.01 (1.00-1.03), P = 0.046].

CONCLUSION

TTS patients with VAs and NYHA class III-IV on admission and higher QTc at 48 h are at increased risk of subacute VAs occurrence, associated with higher in-hospital mortality. Awareness of this potential complication is critical for proper patients management.

Pathophysiology of Takotsubo Syndrome: JACC State-of-the-Art Review

Takotsubo syndrome (TTS) has been a recognized clinical entity for 31 years, since its first description in 1990. TTS is now routinely diagnosed in patients who present with acute chest pain, electrocardiographic changes, troponin elevation, unobstructed coronary arteries, and a typical pattern of circumferential left ventricular wall motion abnormalities that usually involve the apical and midventricular myocardium. Increasing understanding of this intriguing syndrome stems from wider recognition, possible increasing frequency, and a rising number of publications focused on the pathophysiology in clinical and laboratory studies. A comprehensive understanding of TTS pathophysiology and evidence-based treatments are lacking, and specific and effective treatments are urgently required. This paper reviews the pathophysiology of this fascinating syndrome; what is known from both clinical and preclinical studies, including review of the evidence for microvascular dysfunction, myocardial beta-adrenergic signaling, inflammation, and electrophysiology; and where focused research needs to fill gaps in understanding TTS.

"Apical sparing" T-wave inversion in a case of mid-ventricular takotsubo syndrome

Previous studies showed that myocardial edema correlates with dynamic T-wave inversion and QTc prolongation in a variety of acute cardiovascular diseases including takotsubo syndrome (TTS). We reported the case of a patient with "atypical" (mid-ventricular) TTS showing a unique pattern of diffuse T-wave inversion that spared only the apical precordial leads V3-V4. Cardiac magnetic resonance (CMR) showed myocardial edema involving all mid-ventricular segments but not the apex. Both ECG and CMR normalized at follow-up evaluation. This case further reinforces the theory of an association between presence and regional distribution of acute myocardial inflammation and dynamic repolarization changes.

A valuable cardiac magnetic resonance investigation after MINOCA/takotsubo Syndrome: a case report

Myocardial infarction with non-obstructive coronary arteries is a working diagnosis that includes takotsubo cardiomyopathy/syndrome (TTS). Cardiac magnetic resonance (CMR) is useful for establishing the underlying aetiology of myocardial infarction with non-obstructive coronary arteries during the acute phase, but its role in follow-up is less well established. A 35-year-old man with several cardiac risk factors presented 3 days after his sister's death with biochemical and clinical features of acute myocardial infarction without coronary artery obstruction on angiography but with diagnostic features of TTS on CMR, including oedema but no late gadolinium enhancement. Subsequent CMR 3 months later revealed left ventricular late gadolinium enhancement suggesting previous acute myocardial infarction. Although the initial diagnosis of TTS was robust according to established criteria, it remained uncertain whether the later ischaemic injury was related to an ischaemic event at presentation or occurred in the intervening period. Nevertheless, CMR may have an extended role in the follow-up of these patients and may reveal additional, actionable pathology.

Diagnostic and prognostic value of low QRS voltages in cardiomyopathies: old but gold

The interpretation of 12-lead resting electrocardiogram (ECG) in patients with a definitive diagnosis or with the suspicion of a cardiomyopathy represents a cornerstone for the diagnostic work up and management of patients. Although low electrocardiographic QRS voltages (LQRSV) detected by 12-lead resting ECG have historically been acknowledged by physicians, in view of recent evidence on the demonstration of myocardial scar by cardiac magnetic resonance and its relevance as a cause of sudden cardiac death even in young individuals, a new interest has been raised about the utility of LQRSV in the clinical practice. Beyond their diagnostic value, LQRSV have also demonstrated a prognostic role in different cardiomyopathies. The present review summarizes the diagnostic and prognostic value of LQRSV in cardiomyopathies, reporting the new evidence, primarily based on advanced imaging studies, supporting the clinical utility of this parameter.

Cardiovascular disease in women: insights from magnetic resonance imaging

The presentation and identification of cardiovascular disease in women pose unique diagnostic challenges compared to men, and underrecognized conditions in this patient population may lead to clinical mismanagement.This article reviews the sex differences in cardiovascular disease, explores the diagnostic and prognostic role of cardiovascular magnetic resonance (CMR) in the spectrum of cardiovascular disorders in women, and proposes the added value of CMR compared to other imaging modalities. In addition, this article specifically reviews the role of CMR in cardiovascular diseases occurring more frequently or exclusively in female patients, including Takotsubo cardiomyopathy, connective tissue disorders, primary pulmonary arterial hypertension and peripartum cardiomyopathy. Gaps in knowledge and opportunities for further investigation of sex-specific cardiovascular differences by CMR are also highlighted.

Dispersion of ventricular repolarization: Temporal and spatial

Repolarization heterogeneity (RH) is an intrinsic property of ventricular myocardium and the reason for T-wave formation on electrocardiogram (ECG). Exceeding the physiologically based RH level is associated with appearance of life-threatening ventricular arrhythmias and sudden cardiac death. In this regard, an accurate and comprehensive evaluation of the degree of RH parameters is of importance for assessment of heart state and arrhythmic risk. This review is devoted to comprehensive consideration of RH phenomena in terms of electrophysiological processes underlying RH, cardiac electric field formation during ventricular repolarization, as well as clinical significance of RH and its reflection on ECG parameters. The formation of transmural, apicobasal, left-to-right and anterior-posterior gradients of action potential durations and end of repolarization times resulting from the heterogenous distribution of repolarizing ion currents and action potential morphology throughout the heart ventricles, and the different sensitivity of myocardial cells in different ventricular regions to the action of pharmacological agents, temperature, frequency of stimulation, etc., are being discussed. The review is focused on the fact that RH has different aspects – temporal and spatial, global and local; ECG reflection of various RH aspects and their clinical significance are being discussed. Strategies for comprehensive assessment of ventricular RH using different ECG indices reflecting various RH aspects are presented.

The prognostic value of dispersion of repolarization in stress cardiomyopathy

INTRODUCTION

Although abnormalities of ventricular repolarization are a hallmark of SC, their clinical impact on management remains to be determined. This study sought to evaluate the prognostic value of dispersion of repolarization in stress cardiomyopathy (SC) with regards to major cardiac events (MCE), recovery time, and recurrence.

METHODS

This study analyzed data from258 patients with SC, from January 2009 to January 2018. Standard 12 lead ECG recordings during the acute, subacute, and recovery phases were collected for each eligible patient. Logistic regression was used to identify independent predictors of MCE, a composite of 30 day all-cause mortality, cardiogenic shock, life-threatening ventricular arrhythmias, and stroke.

RESULTS

Among the 101 eligible patients (80.2% females, mean age 45.8 ± 11.5 years) in the study cohort, MCE occurred in 16 patients (15.8%). Cox regression analysis identified two independent predictors of MCE: increased ΔQT dispersion ≥ 40 ms (HR 1.31, 95% CI 1.05-9.77, p = 0.029) and increased Δnegative T wave amplitude dispersion ≤ -2.0 mV (HR 1.25, 95% CI 1.11-11.93, p = 0.018) during the subacute phase. The final regression model had good accuracy (sensitivity 81.3%, specificity 96.5%) and discriminative power (AUC 0.89, 95% CI 0.83-0.95). Kaplan-Meier analysis revealed that there was increasing MCE in patients with zero, one, or two predictors (log rank p < 0.001). In addition, patients with increased dispersion also had a significantly longer time to achieve complete recovery (21.4 ± 6.8 vs. 8.5 ± 4.3 days, p = 0.012) and a higher incidence of recurrence (31.3% vs. 2.4%, p = 0.011) of SC.

CONCLUSION

Evaluation of dynamic changes of dispersion of repolarization is a simple bed-side tool with high predictive accuracy for prognostication of short term adverse outcomes, delayed recovery, and recurrence in patients with SC.

Troponin-Positive Non-Obstructive Coronary Arteries and Myocardial Infarction with Non-Obstructive Coronary Arteries: Definition, Etiologies, and Role of CT and MR Imaging

In approximately 10% of patients with acute myocardial infarction (MI), angiography does not reveal an obstructive coronary stenosis. This is known as myocardial infarction with non-obstructive coronary arteries (MINOCA), which has complex and multifactorial causes. However, this term can be confusing and open to dual interpretation, because MINOCA is also used to describe patients with acute myocardial injury caused by ischemia-related myocardial necrosis. Therefore, with regards to this specific context of MINOCA, the generic term for MINOCA should be replaced with troponin-positive with non-obstructive coronary arteries (TpNOCA). The causes of TpNOCA can be subcategorized into epicardial coronary (causes of MINOCA), myocardial, and extracardiac disorders. Cardiac magnetic resonance imaging can confirm MI and differentiate various myocardial causes, while cardiac computed tomography is useful to diagnose the extracardiac causes.

Cardiovascular magnetic resonance in myocardial infarction with non-obstructive coronary arteries patients: A review

The diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) necessitates documentation of an acute myocardial infarction (AMI), non-obstructive coronary arteries, using invasive coronary angiography or coronary computed tomography angiography and no clinically overt cause for AMI. Historically patients with MINOCA represent a clinical dilemma with subsequent uncertain clinical management. Differential diagnosis is crucial to choose the best therapeutic option for ischemic and non-ischemic MINOCA patients. Cardiovascular magnetic resonance (CMR) is able to analyze cardiac structure and function simultaneously and provides tissue characterization. Moreover, CMR could identify the cause of MINOCA in nearly two-third of patients providing valuable information for clinical decision making. Finally, it allows stratification of patients with worse outcomes which resulted in therapeutic changes in almost half of the patients. In this review we discuss the features of CMR in MINOCA; from exam protocols to imaging findings.

The relationship between J wave and ventricular tachycardia during Takotsubo cardiomyopathy

Background and objectives

Takotsubo cardiomyopathy (TTC) occasionally causes life-threatening ventricular arrhythmia. J wave on surface electrocardiography (sECG) has also been associated with idiopathic ventricular fibrillation and cardiac events; therefore, we investigated whether the presence of J wave on sECG is a potential risk factor for ventricular arrhythmia in patients with TTC.

Subjects and methods

We performed a retrospective study in 79 patients who were diagnosed with TTC from 2010 to 2014. Among them, 20 (25.3%) were diagnosed with ventricular tachycardia (VT). The J wave on the sECG was defined as J point elevation manifested through QRS notching or slurring at least 1 mm above the baseline in at least two leads.

Results

A higher prevalence of ventricular tachycardia was observed in patients with J wave. The corrected QT interval (QTc) was significantly longer in the VT group than in the non-VT group. In a multivariate analysis, the presence of J wave appeared to be the only independent predictors of VT [Hazard Ratio (HR) 3.5, p = 0.019].

Conclusion

Our results suggest that the presence of J wave on the sECG is significantly associated with VT, and appear to indicate that the presence of J wave is a strong and independent predictor of VT in patients with TTC.

Autonomic nervous system in Takotsubo syndrome

Takotsubo syndrome (TTS) is an acute and usually reversible heart failure syndrome with symptoms resembling acute myocardial infarction, however, without obstruction of coronary arteries. In the majority of cases, TTS is preceded by emotional or physical stress and the disease concerns mainly postmenopausal women. Although several hypotheses have been introduced, the pathogenesis of TTS is controversial and still remains to be determined. As reported in recent studies, the role of the autonomic nervous system (ANS) seems to be pivotal in the pathogenesis of TTS. Therefore, the aim of this article is to summarize and discuss the current knowledge of the pathogenesis of TTS with a special focus on the ANS.

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.

Ventricular Fibrillation Induced by Takotsubo Syndrome with Congenital Long QT Syndrome

We herein report a case of congenital long QT syndrome (LQTS) in which the QT interval was prolonged by Takotsubo syndrome (TTS), inducing ventricular fibrillation (VF). The patient was a 55-year-old woman who had been diagnosed with LQTS. Cardiopulmonary arrest occurred while coughing during sleep. VF was observed, and her heartbeat returned after two defibrillations. An electrocardiogram showed marked QT prolongation and large negative T waves. Echocardiography demonstrated hyperkinesis at the base of the left ventricle and akinesis at the apex. As there was no significant stenosis in the coronary artery, she was diagnosed with TTS.

Time Course of Functional Recovery in Takotsubo (Stress) Cardiomyopathy: A Serial Speckle Tracking Echocardiography and Electrocardiography Study

BACKGROUND

Although rapid recovery of cardiac contraction is a hallmark of Takotsubo cardiomyopathy (TTC), the time course of recovery is still ill-defined. We aimed to investigate the time course of left ventricular (LV) functional recovery using 2D speckle tracking echocardiography and electrocardiography (ECG).

METHODS

Thirty-two consecutive patients (65 ± 16 years, 26 women) with TTC were prospectively recruited. ECG and echocardiography were performed at baseline (No. 1), before discharge (No. 2), and at 1 week (No. 3) and 5 weeks (No. 4) after discharge. Echocardiographic images and ECGs were analyzed to measure ejection fraction (LVEF), global and regional longitudinal strain (GLS, RLS), and T wave inversion (TWI) scores.

RESULTS

At baseline, LVEF, GLS, and TWI score were 39 ± 8.8%, -11 ± 4.3%, and 1.8 ± 3.0, respectively. Both LVEF and GLS continued to improve from baseline at the No. 2, No. 3, and No. 4 timepoints (49 ± 9.3%, 56 ± 7.5%, 58 ± 6.8%, respectively, for LVEF and -15 ± 4.2%, -17 ± 3.9%, -19 ± 3.4%, respectively, for GLS). TWI score was decreased at the No. 3 ECG relative to baseline and then increased (No. 2: -2.5 ± 3.0, No. 3: -2.9 ± 5.2, No. 4: -0.3 ± 4.4). In the apical subgroup, the reverse base-to-apex gradient of RLS had disappeared by the No. 3 echocardiography.

CONCLUSIONS

Contractile function as assessed by LVEF and GLS recovered continuously in patients with TTC throughout the acute and subacute phases, with rapid recovery in the acute phase. Negative T wave progressed during the acute phase and recovered more slowly during the subacute phase.

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.

Takotsubo Cardiomyopathy-Acute Cardiac Dysfunction Associated With Neurological and Psychiatric Disorders

Takotsubo cardiomyopathy (TTC) is an acute and reversible cardiac wall motion abnormality of the left myocardium. Although many studies focused on etiology, diagnostic and treatment of TTC, precise clinical guidelines on TTC are not available. Research revealed emotional and physical triggering factors of TTC and emphasized the association of TTC with psychiatric and particularly acute neurological disorders. Similar clinical presentation of acute coronary syndrome (ACS) and TTC patients, makes an anamnestic screening for TTC risk factors necessary. In psychiatric anamnesis affective disorders and chronic anxiety disorders are presumably for TTC. Subarachnoid hemorrhages and status epilepticus are typical acute neurological associated with a higher risk for TTC. Moreover, magnetic resonance imaging (MRI) studies reveled brain alterations of the limbic system and reduced connectivity of central autonomic nervous system structures. Diagnosis of TTC is made by elevation of cardiac enzymes, electrocardiogram (ECG) and visualization of myocardial wall motion. Major differential diagnoses like acute coronary syndrome and myocarditis are hereby in synopsis with anamnesis with respect of possible emotional and physical triggering factors of TTC ruled out. In most cases the TTC typical wall motion abnormalities resolve in weeks and therapy is only necessary in hemodynamic instable patients and if rare complications, like cardiac wall ruptures occur. Recently, the two-parted International expert consensus document on Takotsubo syndrome was published, providing a detailed characterization of TTC and allows clinicians to understand this cardiac dysfunction with a multidisciplinary view.

Comparing the variants of takotsubo syndrome: an observational study of the ECG and structural changes from a New Zealand tertiary hospital

OBJECTIVES

In takotsubo syndrome, QTc prolongation is a measure of risk of potentially fatal arrhythmia. It is not known how this risk, or derangement of other markers, differs across the echo variants of takotsubo syndrome. Therefore, we sought to explore whether apical takotsubo syndrome differs from the variants of the syndrome in more ways than just regional wall motion pattern. As the region of affected myocardium is usually larger, we hypothesised that patients with the classic apical ballooning form of takotsubo syndrome would have more severe derangement of their markers.

DESIGN

Observational study of patients gathered from a prospective database (2010-2018) and by retrospective review (2006-2009).

SETTING

The sole tertiary hospital from a New Zealand region in which case clusters of takotsubo syndrome were precipitated by large earthquakes in 2010, 2011 and 2016.

PARTICIPANTS

A total of 222 patients who met a modified version of the Mayo criteria for takotsubo syndrome were included. All patients had digitally archived echocardiograms that were over-read by a second echocardiologist blinded to the clinical report.

PRIMARY OUTCOME MEASURES

Ejection fraction, peak troponin and QTc interval.

RESULTS

Patients with the apical form were older (p=0.011), had a lower initial left ventricular ejection fraction (35% vs 44%, p<0.0001) and a higher peak high-sensitivity troponin I (hsTnI) (p=0.01) than those with variant forms. There was no difference in the electrical abnormalities between the variants (QTc interval, heart rate, PR interval, QRS duration or T-wave axis). There was also no correlation between any of peak hsTnI, peak QTc and ejection fraction. QTc interval increased on day 2 and peaked on day 3 before falling steeply (p<0.0001).

CONCLUSIONS

The variants of takotsubo syndrome differ in more ways than just their echo pattern but do not differ in their electrical abnormalities. There is a dissociation between the structural and electrical abnormalities. QTc peaks on day 3 and then falls steeply.