J wave and fragmented QRS formation during the hyperacute phase in Takotsubo cardiomyopathy

Association of α-HBDH levels with the severity and recurrence after acute ischemic stroke

OBJECTIVE

α-HBDH serves as a biomarker of myocardial damage and is implicated in adverse outcomes across various critical illnesses. Our study aimed to assess the correlation between α-HBDH levels, and severity and recurrence of acute ischemic stroke (AIS).

METHODS

We enrolled patients with mild-to-moderate AIS within 72 h of onset. Based on the baseline score of the National Institutes of Health Stroke Scale (bNIHSS) at registration, patients were categorized into mild (bNIHSS ≤ 4 points) and moderate AIS groups (4 < bNIHSS ≤ 10 points). Subsequently, based on the normal upper limit of α-HBDH, patients were divided into low-level α-HBDH (≤ 180 U/L) and high-level α-HBDH (> 180 U/L) groups. Multivariate logistic regression analysis and Cox proportional hazard regression analysis were employed to evaluate the relationship between α-HBDH levels and bNIHSS scores as well as the risk of recurrent AIS within 90 days.

RESULTS

We observed a significant association between higher baseline levels of α-HBDH and increased bNIHSS scores, indicating a more severe AIS (odds ratio = 24.449; 95% confidence interval [CI], 8.749-68.324; p < 0.01). Additionally, the risk of recurrent AIS within 90 days was 4.666 times higher in the high-level α-HBDH group compared to the low-level group (hazard ratio = 4.666; 95% CI, 2.481-8.777; p < 0.01).

CONCLUSIONS

The baseline level of α-HBDH is significantly correlated with the severity of AIS and the risk of recurrent AIS within 90 days.

Fragmented QRS, a strong predictor of mortality and major arrhythmic events in patients with nonischemic cardiomyopathy: A systematic review and meta-analysis

Background and Aims

Fragmented QRS (fQRS), which is associated with rhythm disturbances, can predispose the heart to fatal ventricular arrhythmias. Recently, accumulating studies indicates that fQRS is associated with poor prognosis in various types of cardiomyopathies. Therefore, we assessed the association between fQRS with all-cause mortality and major arrhythmic events (MAEs) in patients with nonischemic cardiomyopathy, in this systematic review and meta-analysis study.

Methods

We performed a comprehensive search in databases of PubMed/Medline, EMBASE, and Web of Science from the beginning to December 31, 2022. Published observational studies (cohorts, case-control, or analytical cross-sectional studies) were included that report the prognostic value of fQRS in patients with different types of nonischemic cardiomyopathies for MAEs (sudden cardiac death, sudden cardiac arrest, sustained ventricular tachycardia [VT], ventricular fibrillation [VF], and appropriate shock) and all-cause mortality. We pooled risk ratios (RRs) through raw data and adjusted hazard ratios (aHRs) using "Comprehensive Meta-Analysis" software, Version 2.0.

Results

Nineteen cohort and three analytical cross-sectional studies were included in this meta-analysis involving a total of 4318 subjects with nonischemic cardiomyopathy (1279 with fQRS and 3039 without fQRS). FQRS was significantly associated with an increased risk of all-cause mortality in patients with nonischemic cardiomyopathy (pooled RR: 1.920; 95% confidence interval [CI]: 1.388-2.656, p < 0.0001/pooled HR: 1.729; 95% CI: 1.327-2.251, p < 0.0001). Also, the risk of developing MAEs in the presence of fQRS was significantly increased (pooled RR: 2.041; 95% CI: 1.644-2.533, p < 0.0001/pooled HR: 3.626; 95% CI: 2.119-6.204, p < 0.0001). In the subgroup analysis, the strongest association between fQRS presence and increased MAEs was observed in patients with hypertrophic cardiomyopathy (HCM) (pooled RR: 3.44; 95% CI: 2.07-5.71, p < 0.0001/pooled HR: 3.21; 95% CI: 2.04-5.06, p < 0.0001).

Conclusion

Fragmented QRS could be a prognostic marker for all-cause mortality and MAEs in patients with various types of nonischemic cardiomyopathies, particularly HCM.

Broken Heart Syndrome: Evolving Molecular Mechanisms and Principles of Management

Broken Heart Syndrome, also known as Takotsubo Syndrome (TS), is sudden and transient dysfunction of the left and/or right ventricle which often mimics Acute Coronary Syndrome (ACS). Japan was the first country to describe this syndrome in the 1990s, and since then it has received a lot of attention from researchers all around the world. Although TS was once thought to be a harmless condition, recent evidence suggests that it may be linked to serious complications and mortality on par with Acute Coronary Syndrome (ACS). The understanding of TS has evolved over the past few years. However, its exact etiology is still poorly understood. It can be classified into two main types: Primary and Secondary TS. Primary TS occurs when the symptoms of myocardial damage, which is typically preceded by emotional stress, are the reason for hospitalization. Secondary TS is seen in patients hospitalized for some other medical, surgical, obstetric, anesthetic, or psychiatric conditions, and the dysfunction develops as a secondary complication due to the activation of the sympathetic nervous system and the release of catecholamines. The etiopathogenesis is now proposed to include adrenergic hormones/stress, decreased estrogen levels, altered microcirculation, endothelial dysfunction, altered inflammatory response via cardiac macrophages, and disturbances in the brain-heart axis. The role of genetics in disease progression is becoming the focus of several upcoming studies. This review focuses on potential pathophysiological mechanisms for reversible myocardial dysfunction observed in TS, and comprehensively describes its epidemiology, clinical presentation, novel diagnostic biomarkers, and evolving principles of management. We advocate for more research into molecular mechanisms and promote the application of current evidence for precise individualized treatment.

Transient J wave-like ST-segment elevation in intracerebral hemorrhage: a case report

Background

Certain cerebrovascular events can induce electrocardiography (ECG) abnormalities and cardiac dysfunction. The most frequent patterns reported are nonspecific ST-T change, inverted or broad T wave, prolongation of QT interval as well as ST-segment depression or elevation. Here we present a case of intracerebral hemorrhage (ICH) with transient J wave-like ST-segment elevation accompanied by myocardial lesion.

Case presentation

A 58-year-old woman was admitted to our hospital and diagnosed with right basal ganglia region cerebral hemorrhage. The ECG recorded on the second hospital day showed transient J wave-like ST-segment elevation accompanied by increased myocardial troponin I and myocardial enzyme.

Conclusions

The J wave-like ST-segment elevation may be not a specific ECG signs for primary ischemic heart diseases as it also could be found in ICH patients. We believe that the follow-up ECGs can be used in conjunction with repeated myocardial enzyme analysis and echocardiography to differentiate ICH-ralated J wave-like ST-segment elevation from acute myocardial infarction (AMI), thus avoiding unnecessary cardiac catheterization.

Fragmented QRS predicted major adverse cardiovascular events in patients with coronary artery disease and percutaneous coronary intervention, 10-years of follow-up

Aim    Identifying high-risk groups in patient with coronary artery disease (CAD) is critical for predicting future adverse events. fQRS has been shown to be related to major cardiovascular adverse events (MACE) in patients with CAD. However, predictive value of fQRS for more than 5 yrs has not been evaluated. This study examined the predictive value of fQRS in patients with CAD and percutaneous coronary intervention during a 10‑yrs period.Material and methods    Patients with CAD and percutaneous coronary intervention between March 2007 and May 2009 were included the study. An electrocardiogram was recorded following percutaneous coronary intervention and analyzed for the presence of fQRS. The fQRS pattern was defined as an additional spike inside the QRS complexes of at least two consecutive leads. Patients were followed for 10 yrs. A MACE was all-cause mortality or new-onset decompensated heart failure. Patients were divided into two groups according to presence or absence of MACE, and their clinical variables were compared.Results    Of 1261 patients included in the study, MACE developed in 374 (29.6 %). MACE (+) patients were older (p&lt;0.001), more likely to have diabetes mellitus (p=0.003), fQRS (p&lt;0.001), and ST-elevated myocardial infarction (STEMI) (p&lt;0.001). Multivariable Cox regression analysis revealed that age (p&lt;0.001), STEMI (p=0.001), fQRS (p=0.017), and elevated serum creatinine (p=0.001) were independent predictors of MACE.Conclusion    The presence of fQRS predicted MACE during 10 yrs of follow-up of patients with CAD and percutaneous coronary intervention.

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 Cardiomyopathy: An ST-Elevation Myocardial Infarction Mimic

Takotsubo cardiomyopathy (TC), a rare syndrome often preceded by an emotional or physical trigger, which earned the nickname broken heart syndrome, was first diagnosed in 1990. Takotsubo cardiomyopathy can mimic an ST-elevation myocardial infarction (STEMI). Originally, TC was thought to be self-limiting and benign. However, there is a 4%-5% mortality rate, which is associated with serious complications. The majority of people diagnosed with TC are postmenopausal women, but it can affect all ages. Patients will often present to the emergency department with chest pain and dyspnea. An electrocardiogram (ECG) often demonstrates ST elevation. There is no definitive way to differentiate between TC and STEMI on an ECG. Therefore, all patients need to have emergent coronary angiography with left ventriculography.

Association between Tpeak-Tend/QT and major adverse cardiovascular events in patients with Takotsubo syndrome

BACKGROUND

Conflicting results have been described in the scientific literature regarding the relationship between electrocardiographic parameters and complications in patients with Takotsubo syndrome (TTS). Aim of the present study was to investigate whether there is an association between markers of ventricular repolarization and major adverse cardiovascular events (MACE) during hospitalisation.

METHODS

A retrospective chart review was conducted on a sample of patients with diagnosis of TTS, based on the fulfilment of the revised Mayo Clinic criteria. MACE included acute heart failure, cardiogenic shock, sustained ventricular tachycardia, ventricular fibrillation, and death. The following parameters, assessed on the admission electrocardiogram, were analysed: ST-segment elevation, ST-segment depression, T wave inversion, presence of Q waves, QT interval, QT interval corrected for heart rate, QT-dispersion, Tpeak-Tend (Tpe) interval, Tpe dispersion, Tpe/QT ratio, and QTpeak/QT ratio.

RESULTS

Patients with MACE, compared to patients without MACE, showed more commonly anterior ST-segment elevation and had significantly higher values of Tpe/QT ratio. Low ejection fraction and Tpe/QT ratio > 0.27 identified a sub-population of patients more likely to have MACE during hospitalisation.

CONCLUSIONS

Tpe/QT ratio represents a useful electrocardiographic parameter in the acute phase of TTS.

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.

Electrocardiographic changes in Takotsubo cardiomyopathy

Takotsubo Cardiomyopathy (TC) is a syndrome characterized by reversible left ventricular dysfunction in the presence of possible emotional or physical triggers but without evidence of obstructive coronary artery disease. It has become increasingly reported worldwide and is associated with significant morbidity and mortality. TC may present with an array of electrocardiographic (ECG) findings. These ECG findings, if accurately interpreted, can play an important role in the diagnosis and risk stratification of this syndrome. In the last three decades since the disease was first described, multiple diagnostic criteria have been established. The key diagnostic tools for TC include clinical symptomatology, cardiac biomarkers, non-invasive cardiac imaging, and coronary angiography. The ECG findings in TC can be variable, however, some ECG scores have been proposed in association with TC with reasonably good diagnostic sensitivity and specificity. This article aims to provide a succinct review of important electrocardiographic findings associated with TC and its impact on clinical outcomes.

Ventricular fibrillation and Takotsubo cardiomyopathy triggered by media panic on COVID‐19: A case report

Takotsubo cardiomyopathy has potentially lethal complications and can be caused by a media‐induced diffuse atmosphere of life threatening and panic in preconditioned patients.

Pathogenesis of Ventricular Arrhythmias and Its Effect on Long-Term Prognosis in Patients With Takotsubo Cardiomyopathy

Takotsubo cardiomyopathy (TTC), also known as broken heart syndrome, stress cardiomyopathy (SCM), or apical ballooning syndrome, is a non-ischemic cardiac disease with an initial clinical presentation that is very similar to acute coronary syndrome (ACS). Ventricular arrhythmias (VAs) contribute significantly to an increase in the rates of death in patients with TTC, especially during the acute phase, in which patients with TTC are more susceptible to develop life-threatening arrhythmias (LTA) such as ventricular tachycardia (VT), ventricular fibrillation (VF), torsades de pointes (TdP), and sudden cardiac death (SCD). However, the pathophysiology of TTC and how VA occurs are still a mystery. We aim to review previous literature and discuss the possible mechanisms of VA in TTC patients.

VA usually complicates the acute phase of the disease and worsens the long-term prognosis. Alterations of repolarization (negative T wave, prolonged QTc) indicate a high risk of arrhythmic events (TdP, VT, VF, and SCD). Catecholamine effect on myocardial cells and myocardial edema can create a substrate for the development of VA. Some of the most commonly proposed mechanisms for the development of VA in patients with TTC are coronary vasospasm, myocardial stunning due to catecholamines, re-entry, and triggered activity. Further prospective studies, including a more significant number of patients, are required to understand the disease's pathophysiology better and improve LTA management in patients with TTC.

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.

Prevalence and Significance of an Early Repolarization Electrocardiographic Pattern and Its Mechanistic Insight Based on Cardiac Magnetic Resonance Imaging in Patients With Acute Myocarditis

BACKGROUND

An early repolarization electrocardiographic (ER-ECG) pattern is caused by various pathophysiological conditions and is reported to be a predictor of life-threatening ventricular tachyarrhythmias. However, little evidence has been reported on the prevalence and significance of the ER-ECG pattern in acute myocarditis. This study aimed to investigate the prevalence and significance of the ER-ECG pattern and its mechanistic insight based on the cardiac magnetic resonance findings in patients with acute myocarditis.

METHODS

Thirty patients (23 men; 39.2±19.1 years) with a diagnosis of acute myocarditis by a clinical presentation between March 2011 and April 2018 were retrospectively evaluated. The patients were divided into 2 groups depending on the presence of an ER-ECG pattern on admission.

RESULTS

Nine cases had an ER-ECG pattern, which was defined as terminal QRS notching or slurring with an amplitude of >0.1 mV in at least 2 inferior or lateral leads (early repolarization [ER] group), whereas the remaining 21 cases had broad ST-segment elevation or pathological Q waves (non-ER group). The cardiac troponin T level was significantly higher in the non-ER group than ER group (3.2±4.3 versus 0.9±1.2 ng/mL; P=0.036). The ECG changes returned to baseline along with the normalization of the cardiac biomarkers. Nine of the 21 non-ER group patients, but none of the 9 ER group patients, developed a fulminant course and lethal ventricular tachyarrhythmias. T2-weighted cardiac magnetic resonance showed high-intensity signals over the entire transmural left ventricle in the non-ER group, whereas they were localized to the left ventricular epicardium in the ER group.

CONCLUSIONS

The ER-ECG pattern in acute myocarditis was transient and reversible and was not associated with a worse prognosis. Inflammation/swelling localized to the left ventricular epicardium because of acute myocarditis might provide a mechanistic insight into the ER-ECG pattern.

Fragmented QRS - Its significance

Fragment QRS (fQRS) complex is a myocardial conduction abnormality that indicates myocardial scar. It is defined as additional notches in the QRS complex. Though initially fQRS was defined in the setting of normal QRS duration (<120 m s), later it has been expanded to include conditions with wide QRS complexes as in bundle branch block, ventricular ectopy and paced rhythm, when more than 2 notches are present. It is an important, yet often overlooked marker of mortality and arrhythmic events in many cardiac diseases. The significance of fQRS lies in the fact that it just requires a surface ECG for its recording and the value of information about the condition of the heart it dispenses based on the clinical setting. We review the role of fQRS in predicting adverse cardiac events in various conditions.

The role of multimodality imaging in takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC) is a syndrome of transient left ventricular (LV) dysfunction mimicking acute coronary syndrome. Although the mechanisms underlying the occurrence of TC are unknown, several imaging techniques contribute to its diagnosis. Here we review the current knowledge about TC, in particular, the pathophysiology and the role of imaging including nuclear cardiovascular medicine.

Differences in Initial Electrocardiographic Findings of Apical Takotsubo Syndrome According to the Time from Symptom Onset

No previous study has examined the differences in patient characteristics and initial electrocardiographic findings of Takotsubo syndrome (TTS) according to the time from onset to electrocardiography. Using the Tokyo Cardiovascular Care Unit network registry 2011-2012, we retrospectively identified 106 apical TTS patients in whom symptom onset time was specified, and classified the patients into 5 groups according to the time from onset to the initial electrocardiography: <3 hours (n = 45), 3 to 6 hours (n = 20), 6 to 12 hours (n = 12), 12 to 24 hours (n = 13), and ≥24 hours (n = 16). There was no significant difference across the groups in age, gender, symptoms, triggers, vital signs, blood tests, or in-hospital outcomes. In the electrocardiographic findings, ST-elevation was more frequent in leads V2-V4 than in the other leads, especially in the <24 hour groups, but did not differ significantly across groups. T-wave inversion was more frequent in leads V3-V6, especially in the ≥24 hour group, and differed significantly across groups. The total number of leads with T-wave inversion was significantly larger in the ≥24 hour group than in the <24 hour groups (mean, 5.9 leads vs 1.5 to 2.9 leads; p < 0.001). Isolated ST-elevation was the most frequent pattern of ST-T change in precordial leads (42% to 56%) in the <24 hour groups, while isolated T-wave inversion was the most frequent (44%) in the ≥24 hour group (p = 0.018). Neither ST-elevation nor T-wave inversion was observed in precordial leads in 10 (9%) patients. In conclusion, our results suggest that the initial electrocardiographic findings of apical TTS are affected by the time from onset to electrocardiography and display a wide variation in ST-T changes.

Ventricular arrhythmias in patients with Takotsubo syndrome

Takotsubo syndrome (TTS) is a unique nonischemic cardiac disease characterized by acute myocardial dysfunction of the left and/or right ventricle. Patients are predominantly postmenopausal women and usually present with symptoms indistinguishable from acute coronary syndrome. Although the exact pathomechanisms of TTS remain elusive, increasing evidence suggests that sympathetic overdrive and catecholamine excess might play a central role. Despite the complete recovery of ventricular dysfunction within several days to weeks, patients with TTS exhibit considerable short- and long-term mortality rates and ventricular arrhythmias have been identified as key contributor to morbidity and mortality. This article summarizes the prevalence, underlying mechanisms, therapeutic strategies, and prognostic implications of ventricular arrhythmias in TTS. Furthermore, the need for implantable cardioverter-defibrillators is discussed in view of the transient character of the disease.

International Expert Consensus Document on Takotsubo Syndrome (Part II): Diagnostic Workup, Outcome, and Management

The clinical expert consensus statement on takotsubo syndrome (TTS) part II focuses on the diagnostic workup, outcome, and management. The recommendations are based on interpretation of the limited clinical trial data currently available and experience of international TTS experts. It summarizes the diagnostic approach, which may facilitate correct and timely diagnosis. Furthermore, the document covers areas where controversies still exist in risk stratification and management of TTS. Based on available data the document provides recommendations on optimal care of such patients for practising physicians.

The ECG in the differential diagnosis between takotsubo cardiomyopathy and acute coronary syndrome

INTRODUCTION

Takotsubo cardiomyopathy (TC) is an acquired cardiomyopathy affecting mostly postmenopausal women mimicking an acute coronary syndrome (ACS). TC clinical presentation involves chest pain, elevated cardiac enzymes, wall motion abnormalities and electrocardiographic changes, all of which share striking similarities to ACS. Areas covered: Differential diagnosis between TC and ACS can be complex since there are no reliable and widely-accepted electrocardiographic criteria and, at the moment, only coronary angiography can rule out one of the two diagnoses with good certainty. The present review will discuss the pros and cons of the ECG in TC, focusing on how the signal changes through the acute phase, the hospitalization, and after discharge. Specific information will be provided for each component of the ECG trace, and potential pitfalls will be highlighted, in order get to the core of this important unmet clinical issue. Expert commentary: There are at least several reasons why the ECG is still not considered a useful tool in differential diagnosis between TC and ACS. These include recent awareness of the syndrome, lack of evidence-based therapy, and, more importantly, a wide range of ECG features according to race, patient characteristics, wall motion abnormalities, triggers, and time from symptoms onset.

[Prevalence of electrocardiographic abnormalities in patients with myasthenia gravis]

OBJECTIVE

Myasthenia gravis (MG) is an immunological disorder of the neuromuscular junction, characterized by easy fatigability and weakness of the skeletal muscles. However, it has sometimes been reported that heart diseases including cardiomyopathies leading to sudden death have been observed in patients with MG. We studied the prevalence of electrocardiographic (ECG) abnormalities and heart disease in patients newly diagnosed with MG who had not received immunotherapy.

METHODS

Fifty-three patients with MG were enrolled in our study. We reviewed the ECG recordings of all patients on admission, and assessed the prevalence of ECG abnormalities and heart diseases associated with MG.

RESULTS

Thirty-three (62.2%) patients had ECG abnormalities, including early repolarization (15 patients), negative T waves (9 patients), left ventricular hypertrophy (5 patients), and prolonged QTc (4 patients). A higher frequency of early repolarization was observed in patients with MG compared to healthy subjects.

DISCUSSION

ECG abnormalities in patients with MG were more prevalent in our series than in the general population. This may be because of the increasing incidence of MG in the elderly. However, we also observed that younger patients developed severe heart disease, indicating the possibility of other mechanisms, such as the presence of antimyocardial antibodies. Clinicians should be aware of the complications of heart disease in patients with MG, especially during the perioperative period for thymectomy or thymomectomy.

J Waves Are Associated With the Increased Occurrence of Life-Threatening Ventricular Tachyarrhythmia in Patients With Nonischemic Cardiomyopathy

INTRODUCTION

Recent studies showed that J waves were associated with higher incidence of ventricular tachyarrhythmia (VT/VF) in patients with idiopathic ventricular fibrillation (VF) and myocardial infarction. We sought to assess the association between J waves and VT/VF in patients with nonischemic cardiomyopathy (NICM).

METHODS AND RESULTS

We retrospectively enrolled 109 patients (79 men; mean age, 60 ± 15 years) with NICM who underwent implantable cardioverter defibrillator (ICD) implantation. The primary endpoint of this study was the occurrence of appropriate device therapy due to sustained VT/VF. The J wave was electrocardiographically defined as an elevation of the terminal portion of the QRS complex of >0.1 mV in at least 2 contiguous inferior or lateral leads. Among the 109 patients, 37 (34%) experienced an episode of appropriate device therapy during a median follow-up period of 25.9 (IQR 11.5-54.3) months. Kaplan-Meier curves showed that the presence of J waves on the 12-lead ECG obtained before device implantation was associated with an increased occurrence of appropriate device therapy (P < 0.001). Multivariate Cox proportional regression analysis revealed that the presence of J waves (HR 2.95; 95% CI 1.31-6.64; P = 0.009) was an independent predictor for the occurrence of appropriate device therapy. In the subgroup analysis of the patients with dilated or hypertrophic cardiomyopathy, J wave tended to increase the occurrence of appropriate device therapy (P = 0.056 and P = 0.092, respectively).

CONCLUSIONS

The presence of J waves was an independent predictor for the occurrence of appropriate device therapy in patients with NICM who underwent ICD implantation.

Therapy of stress (takotsubo) cardiomyopathy: present shortcomings and future perspectives

Several therapeutic options are available for the treatment of the acute phase of stress cardiomyopathy, pharmacological (β-blockers, diuretics, anticoagulants, antiarrhythmics, noncatecholamine inotropics [levosimendan]), and nonpharmacological (intra-aortic balloon pumping, extracorporeal membrane oxygenation), according to the wide possible clinical presentation and course of the disease. However, there is a gap in evidence, and very few data come from randomized and adequately powered studies. Some evidence supports the use of β-blockers, in particular with a short half-life, in the case of left ventricular outflow tract obstruction, and angiotensin-converting enzyme inhibitors in secondary prevention. Future perspectives include the study of genetic basis of stress cardiomyopathy, role of miRNA and neurovegetative modulation. Randomized studies, however, are surely warranted.

Takotsubo Syndrome: Insights from Japan

We report the history and new insights of takotsubo syndrome based on the achievements that Japanese researchers have contributed and summarize the evidence originally presented from Japan. Takotsubo syndrome is a newly described heart failure characterized by transient left ventricular dysfunction. We should be aware of this entity as a syndrome, not actual cardiomyopathy. Japanese researchers focus on the experimental approaches for clinical diagnosis and treatment of takotsubo syndrome. As representatives from a country originally naming this syndrome takotsubo, a global registry for takotsubo syndrome including Japan should be established.

Total Mortality, Major Adverse Cardiac Events, and Echocardiographic-Derived Cardiac Parameters with Fragmented QRS Complex

BACKGROUND

Fragmented QRS complex (fQRS), an easily evaluated noninvasive electrocardiographic parameter, is associated with worse outcomes in patients with several cardiovascular conditions. The presence of fQRS on ECG may be an indicator of myocardial damage in patients with coronary artery disease (CAD). In this article, we performed a meta-analysis in order to characterize the presence of fQRS on ECG in patients with CAD.

METHODS

We searched English-language randomized controlled trials involving fQRS on ECG in patients with CAD (n = 3279 patients, 12 trials). Two reviewers independently extracted data. Data on LVEF, LVESD, LVEDD, LVESV, LVEDV, total mortality, stroke, and MACE were collected. fQRS was performed a comparison with non-fQRS, calculating pooled relatives risk (RRs) and weighted mean difference (WMD), and associated 95% confidence intervals (CIs).

RESULTS

fQRS was associated with significant increased WMD of LVEDD (WMD, 2.26; 95%CI, 0.92 to 0.36, P = 0.0009), LVESD (WMD, 2.71; 95%CI, 1.23 to 4.19, P = 0.0003), LVEDV (WMD, 31.37; 95%CI, 24.82 to 37.92, P < 0.00001), and LVESV (WMD, 28.45; 95%CI, 22.92 to 33.98, P < 0.00001). As compared to non-fQRS, fQRS increased risk of total mortality (RR, 3.09; 95%CI, 1.76 to 5.44, P < 0.0001) and MACE (RR, 2.85; 95%CI, 1.98 to 4.09, P < 0.00001) in patients with CAD. However, a decreased trend was observed for LVEF (WMD, -3.59; 95%CI, -7.05 to -0.12, P = 0.04). For the incidence of stoke, there was no difference between fQRS and non-fQRS group.

CONCLUSIONS

Our findings indicate that fQRS is a valuable factor to predict total mortality and MACE in patients with CAD.

Early repolarization and positive T-wave alternans as risk markers for life-threatening arrhythmias in patients with vasospastic angina

BACKGROUND

Several arrhythmogenic markers have been suggested as predictors for risk of life-threatening arrhythmias during symptom-free periods in vasospastic angina (VSA), but no definite conclusion has been drawn.

OBJECTIVE

To investigate prevalence of fatal ventricular tachyarrhythmia in VSA and its relation to appearance of early repolarization (ER) and positive T wave alternans (p-TWA) in patients with VSA during symptom-free periods.

METHODS

We studied 116 consecutive patients with chest pain who underwent an acetylcholine provocation test for VSA diagnosis. Patients were divided into two groups with positive (VSA group; 66 cases) and negative (control group; 50 cases) provocation test results. The presence of ER on electrocardiogram and the modified moving average analysis of TWA during symptom-free periods were explored.

RESULTS

The incidences of ER and p-TWA were higher in the VSA than in the control group (P=0.001 and P=0.006, respectively). Multivariate analysis revealed that ER and p-TWA were independent predictors of VSA (odds ratio, 5.65 and 4.94; 95% confidence interval: 1.11-28.9 and 1.22-19.9, respectively). The incidence of coexisting baseline ER and p-TWA was significantly higher in VSA patients with life-threatening arrhythmic events (3/3 vs. 6/38; P<0.001) than in those without.

CONCLUSIONS

VSA patients with arrhythmic events showed a high incidence of ER and p-TWA during symptom-free periods. Therefore, baseline ER and p-TWA may help to identify VSA patients at high risk for life-threatening arrhythmias.

Epidemiology and pathophysiology of Takotsubo syndrome

Takotsubo syndrome is an acute cardiac syndrome first described in 1990 and characterized by transient left ventricular dysfunction affecting more than one coronary artery territory, often in a circumferential apical, mid-ventricular, or basal distribution. Several pathophysiological explanations have been proposed for this syndrome and its intriguing appearance, and awareness is growing that these explanations might not be mutually exclusive. The reversible apical myocardial dysfunction observed might result from more than one pathophysiological phenomenon. The pathophysiology of Takotsubo syndrome is complex and integrates neuroendocrine physiology, potentially involving the cognitive centres of the brain, and including the hypothalamic-pituitary-adrenal axis. Cardiovascular responses are caused by the sudden sympathetic activation and surge in concentrations of circulating catecholamines. The multiple morphological changes seen in the myocardium match those seen after catecholamine-induced cardiotoxicity. The acute prognosis and recurrence rate are now known to be worse than initially thought, and much still needs to be learned about the epidemiology and the underlying pathophysiology of this fascinating condition in order to improve diagnostic and treatment pathways.

Some Controversies about Early Repolarization: The Haïssaguerre Syndrome

Controversy has followed the groundbreaking and cornerstone paper of Haïssaguerre et al. Much of this controversy has been due to the use of the term "early repolarization pattern" and possible waveform morphologies on the standard 12-lead ECG ( it is 10 second strip) that could predict who will manifest the malignant arrhythmogenic syndrome described by Haïssaguerre et al. The standard ECG definition of early repolarization pattern (ERP) or early repolarization variant (ERV) since then has changed its clinical meaning for a surface electrocardiographic waveform from benign to malignant. The new definition of ERP/ERV contains only J wave but ST-segment elevation is no more obligatory. In the old definition, early repolarization pattern (ERP) or early repolarization variant (ERV) 3 is a well-recognized idiopathic electrocardiographic phenomenon considered to be present when at least two adjacent precordial leads show elevation of the ST segment, with values equal or higher than 1 mm. In the new electrocardiographic ERP concept, the ST segment may or may not be elevated and can be up-sloping, horizontal or down-sloping while in the old ERP/ERV concept it must be elevated at least 1 mm in at least two adjacent leads and the variant is characterized by a diffuse elevation of the ST segment of upper concavity, ending in a positive T wave of V2 to V4 or V5 and prominent J wave and ST-segment elevation predominantly in left precordial leads. The phenomenon constitutes a normal variant; it is almost a rule in athletes (present in 89% of the cases in this universe).

Pathophysiology of takotsubo syndrome: temporal phases of cardiovascular responses to extreme stress

Takotsubo syndrome (TTS), also known as takotsubo cardiomyopathy, is an acute heart failure syndrome that typically occurs after a period of great emotional stress. The archetypal patient is a postmenopausal woman who presents with chest pain, ST-segment elevation and acute hypokinesia of the apical and middle segment of the left ventricle that extends beyond the territory of a single coronary artery, coupled with hyperkinesia of the basal myocardium. Recent preclinical and clinical studies have shown the importance of high catecholamine levels in precipitating TTS. We propose that this is caused by activation of β-adrenoceptors and the subsequent activation of a negatively-inotropic pathway, perhaps to protect the heart from catecholamine overload. We explore the pathophysiology of TTS according to its "phases", both preclinically and clinically. This will show that the condition is not one of static apical hypokinesia that simply improves, but rather a dynamic condition that changes as the disease progresses. We hope that further exploration of TTS using its "phases" will aid in its characterization, diagnosis and treatment.