Acute cardiac sympathetic disruption in the pathogenesis of the takotsubo syndrome: a systematic review of the literature to date

Small conductance calcium-activated potassium channel contributes to stress induced endothelial dysfunctions

Patients with Takotsubo syndrome displayed endothelial dysfunction, but underlying mechanisms have not been fully clarified. This study aimed to explore molecular signalling responsible for catecholamine excess induced endothelial dysfunction. Human cardiac microvascular endothelial cells were challenged by epinephrine to mimic catecholamine excess. Patch clamp, FACS, ELISA, PCR, and immunostaining were employed for the study. Epinephrine (Epi) enhanced small conductance calcium-activated potassium channel current (ISK1-3) through activating α1 adrenoceptor. Phenylephrine enhanced edothelin-1 (ET-1) and reactive oxygen species (ROS) production, and the effects involved contribution of ISK1-3. H2O2 enhanced ISK1-3 and ET-1 production. Enhancing ISK1-3 caused a hyperpolarization, which increases ROS and ET-1 production. BAPTA partially reduced phenylephrine-induced enhancement of ET-1 and ROS, suggesting that α1 receptor activation can enhance ROS/ET-1 generation in both calcium-dependent and calcium-independent ways. The study demonstrates that high concentration catecholamine can activate SK1-3 channels through α1 receptor-ROS signalling and increase ET-1 production, facilitating vasoconstriction.

Role of Positive Emotions in Takotsubo Cardiomyopathy

Takotsubo Cardiomyopathy, also known as "broken heart syndrome," is a transient cardiac condition characterized by sudden left ventricular dysfunction, often triggered by emotional stress or significant life events. While research has predominantly focused on the impact of negative emotions and emotional stressors, there is a growing interest in understanding the role of positive emotions in this unique cardiac syndrome. This narrative review explores the emerging research on positive emotions and Takotsubo Cardiomyopathy. It provides an overview of studies investigating the relationship between positive emotions and the condition, highlighting key findings and observations. Positive emotions, such as joy, happiness, gratitude, and optimism, have been associated with improved emotional well-being, better-coping mechanisms, and potential cardiovascular protection. Some studies suggest that individuals experiencing higher levels of positive emotions may have a reduced risk of developing Takotsubo Cardiomyopathy. However, the research in this area is still limited, with small sample sizes and challenges in quantifying positive emotions. Additionally, the interplay between positive and negative emotions requires further exploration to fully understand their impact on cardiovascular health. Despite these limitations, harnessing positive emotions in cardiac care holds promise for enhancing patient outcomes and emotional well-being. Integrating positive psychology into clinical practice and cardiac rehabilitation may lead to more holistic and patient-centered approaches to cardiovascular care. Further longitudinal studies, interventional trials, and mechanistic investigations are needed to strengthen the evidence base and identify potential therapeutic perspectives. As research progresses, addressing these gaps will provide valuable insights into the complex relationship between emotions and cardiovascular health, benefiting patients affected by Takotsubo Cardiomyopathy and other cardiovascular conditions.

Takotsubo Syndrome and Sudden Cardiac Death

Takotsubo syndrome (TTS), triggered by intense emotional or physical stress, occurring most commonly in post-menopausal women, presents as an ST-elevation myocardial infarction (MI). Cardiovascular complications occur in almost half the patients with TTS, and the inpatient mortality is comparable to MI (4-5%) owing to cardiogenic shock, myocardial rupture, or life-threatening arrhythmias. Thus, its prognosis is not as benign as previously thought, as it may cause mechanical complications (cardiac rupture) and potentially lethal arrhythmias and sudden cardiac death (SCD). Similar to MI, some patients may perish before reaching the hospital due to out-of-hospital cardiac arrest; this may lead to underestimation of the actual SCD risk. Furthermore, after discharge, some patients may develop late SCD and/or TTS recurrence that may result in SCD. There are risk factors for SCD in TTS patients, such as severe/persistent QT-interval prolongation inciting torsade-de-pointes, other ECG abnormalities (diffuse giant negative T-waves, widened QRS-complex), bradyarrhythmias, comorbidities, concurrent obstructive coronary artery disease or vasospasm, male gender, older age, severe left ventricular dysfunction, and use of sympathomimetic drugs. All these issues are herein reviewed, case reports/series and data from large cohort studies and meta-analyses are analyzed, risk factors are tabulated, and proarrhythmic effects and management strategies are discussed and pictorially illustrated.

Peri-operative Takotsubo syndrome after non-cardiac surgery: a retrospective nested case-control study

AIMS

Takotsubo syndrome (TTS) is an acute reversible cardiac dysfunction that may occur during the peri-operative period and among patients with serious illness. We aimed to evaluate the clinical characteristics, peri-operative management, and prognosis of peri-operative TTS (pTTS) and explore the factors associated with pTTS.

METHODS

We conducted a retrospective nested case-control study using the database of patients who underwent in-hospital non-cardiac surgeries between January 2017 and December 2020 in Peking University Third hospital. Cases were adult patients diagnosed TTS at discharge who were matched with four controls based on operative types. Multivariable conditional logistic regression was used to identified the factors associated with pTTS. The area under the curve (AUC) was used to evaluate the diagnostic efficacy.

RESULTS

Among the 128 536 patients underwent non-cardiac surgery, 20 patients with pTTS and 80 patients without were enrolled in this study. The incidence of pTTS was about 0.016% in our centre. The median age of patients with pTTS was 52.5 (38.25, 76.25) years, although 90% of them were female. Fifty per cent (9 cases) of female patients were pre-menopausal. Caesarean section has the highest proportion of pTTS (30% of the pTTS cases) with the incidence of caesarean section-related pTTS of 0.06% in our centre. A high prevalence of non-apical ballooning pattern of regional wall motion abnormality (seven cases, 35%) and a high mortality (two cases, 10%) were observed. Left ventricular ejection fraction (LVEF) of patients with pTTS was significantly decreased (41.7 ± 8.8%). In the acute phase, supportive treatments aiming to reduce life-threatening complications were main treatment strategies. After receiving systematic treatment, significant improvements were observed in LVEF (63.1 ± 13.5%), with median recovery time of LVEF of 7.48 days. Leucocyte count [odds ratio (OR): 4.59; 95% confidence interval (CI): 1.10-19.15], haemoglobin (HGB) (OR: 10.52; 95% CI: 1.04-106.36), and the revised cardiac risk index (RCRI) score (OR: 6.30; 95% CI: 1.05-37.88) were the factors significantly associated with pTTS. The RCRI score performed poorly in the prediction of pTTS (AUC: 0.630; 95% CI: 0.525-0.735). After adding leucocyte count and HGB into the RCRI score, the AUC was significantly improved (AUC: 0.768; 95% CI: 0.671-0.865; P = 0.001).

CONCLUSIONS

Patients with pTTS have some differences compared with common TTS, including higher proportion of pre-menopausal female, higher prevalence during caesarean section, higher prevalence of non-apical ballooning pattern of regional wall motion abnormality, and higher mortality. The RCRI score performed poorly in the evaluation of pTTS. Adding HGB and leucocyte count into the RCRI score could significantly improve its predictive performance.

The heart of the matter: secretory pheochromocytoma presenting as recurrent biventricular heart failure (Takotsubo cardiomyopathy)

Takotsubo’s syndrome (TS) is an acute, transient cardiomyopathy occurring secondary to physical or emotional stressors through catecholamine excess. Secretory pheochromocytomas have been previously implicated in cases of TS (PTS), however, often present atypically, are associated with reoccurrence, and have higher rates of complications. We describe the case of a 70-year-old female who presented central chest pain, hypotension and electrocardiogram changes on a background of a 6-month prior episode of resolved Takotsubo’s with unknown cause. After progressing to cardiogenic shock with biventricular failure, computerized tomography coronary aortogram revealed an incidental adrenal mass, later proven to be a secretory pheochromocytoma on biochemistry and subsequent histology. PTS has been associated with recurrence and rarely presents as cardiogenic shock. This case highlights the complexity of TS presentations and complications and the diagnostic delays that may occur in PTS.

Cardiovascular Manifestations and Complications of Pheochromocytomas and Paragangliomas

Pheochromocytomas and paragangliomas (PPGLs) are rare neuro-endocrine tumors. The catecholamine surge causes paroxysmal or chronic secondary hypertension. PPGLs may present as hypertensive- or PPGL-crisis with severe life-threatening cardiac and cerebrovascular complications. PPGLs-induced cardiac manifestations have been reported with diagnoses as PPGLs-induced electrocardiogram (ECG) changes “mimicking acute myocardial infarction”, arrhythmias, myocarditis, acute coronary syndrome, dilated cardiomyopathy, and lately as takotsubo syndrome. Critical analysis of these reports reveals that most of these cardiac manifestations have certain features in common. They have a dramatic clinical presentation and are reversible if the disease is treated with appropriate medical therapy and surgical resection of the PPGL tumor. They may have the same repolarization ECG changes irrespective of the clinical cardiac diagnosis, usually associated with mild to moderate elevations of myocardial biomarkers as troponins and normal coronary arteries. The histopathological findings are usually focal or multifocal in the form hypercontracted sarcomeres and contraction band necrosis (myofibrillar degeneration) with subsequent secondary mononuclear cell infiltration. Evidences argue the PPGL caused surge of catecholamines triggers hyperactivation of the sympathetic nervous system with cardiac sympathetic nerve terminal disruption with norepinephrine spillover causing the cardiac complications. A comprehensive review of various reported cardiovascular manifestations and complications of PPGLs are presented.

Autonomic neurocardiogenic syndrome is stonewalled by the universal definition of myocardial infarction

Myocardial infarction (MI) is defined as myocardial cell death due to prolonged myocardial ischemia. Clinically, troponin rise and/or fall have become the “defining feature of MI” according to the universal definition of MI (UD-MI). Takotsubo syndrome (TS) and TS-related disease conditions also cause troponin elevation with typical rise and/or fall pattern but through a mechanism other than coronary ischemia. By strict application of the clinical diagnostic criteria for type-1 MI, type-2 MI, type-3 MI, and MI with non-obstructive coronary arteries according to the UD-MI including the fourth one published recently, TS and most of the 26 other causes of troponin elevation mentioned in the fourth UD-MI may erroneously be classified as MI. The existing evidence argues for the case that TS by itself is not a MI. Hyper-activation of the autonomic-sympathetic nervous system including local cardiac sympathetic hyper-activation and disruption with nor-epinephrine churn and spillover is the most probable cause of TS. This autonomic neuro-cardiogenic (ANCA) mechanism results in myocardial “cramp” (stunning), the severity and duration of which depend on the degree of the sympathetic-hyperactivation and nor-epinephrine spillover. The myocardial cramp may squeeze the cytosolic free troponin pools causing mild to moderate troponin elevation in TS and TS-related disease conditions. This ANCA syndrome, which has hitherto been enveloped by the UD-MI over more than one decade, may occur in acute, recurrent, and chronic forms. In this critical review, the controversies of UD-MI, evidence for ANCA syndrome, and a hypothetical mechanism for the troponin elevation in ANCA syndrome are provided.

Clinical features, complications, and outcomes of exogenous and endogenous catecholamine-triggered Takotsubo syndrome: A systematic review and meta-analysis of 156 published cases

Innumerable physical stress factors including externally administered catecholamines, and pheochromocytomas and paragangliomas (PPGLs) have been reported to trigger Takotsubo syndrome (TS). A systematic search of PubMed/MEDLINE identified 156 patients with catecholamine‐induced TS up to December 2017. Data were compared within the catecholamine‐induced TS cohort, but some comparisons were also done to a previously published large all‐TS cohort (n = 1750). The mean age was 46.4 ± 16.4 years (72.3% women). The clinical presentation was dramatic with high complication rates in (68.2%, n = 103; multiple complications 34.6%, n = 54). The most common TS ballooning pattern was apical or mid‐apical (45.2%, n = 69), followed by basal pattern (28.8%, n = 45), global pattern (16.0%, n = 25), mid‐ventricular (8.3%, n = 13), focal (0.6%, n = 1), and unidentified pattern (1.9%, n = 3). There was an increase in the prevalence of apical sparing ballooning pattern compared to all‐TS population (37.7% vs 18.3%, P < .00001). Higher complication rates were observed in TS with global ballooning pattern compared to apical ballooning pattern (23/25, 92% vs 38/65, 58.5%; P = .0022). Higher complication rates were observed in patients with age < 50 years than patients >50 years (73/92, 79.3% vs 29/56, 51.8%, P = 0.0009). Recurrence occurred exclusively in patients with PPGL‐induced TS (18/107 patients, 16.8%). PPGL‐induced TS was characterized by more global ballooning's pattern (22/104, 21.2% vs 3/49, 6.1%, P = 0.02), and lower left ventricular ejection fraction (25.54 ± 11.3 vs 31.82 ± 9.93, P = 0.0072) compared to exogenous catecholamine‐induced TS. In conclusion, catecholamine‐induced TS was characterized by a dramatic clinical presentation with extensive left ventricular dysfunction, and high complication rate.

Pheochromocytoma- and paraganglioma-triggered Takotsubo syndrome

Takotsubo syndrome (TS), also known as neurogenic stunned myocardium or broken heart syndrome, is a recognized acute cardiac syndrome. In about 70% of cases, the syndrome is preceded by an emotional or a physical stressor. Among the innumerable physical trigger factors that may induce TS are pheochromocytomas and paragangliomas (PPGLs). PPGL-associated cardiovascular complications as "myocarditis", "myocardial infarction", "reversible cardiomyopathies", and "transient repolarization electrocardiographic changes" have been described since more than 70 years. During the last two decades, dozens of cases of PPGL-induced TS have been reported. PPGLs display increased catecholamine levels, sometimes massively elevated, which may trigger TS, most likely through hyperactivation of sympathetic nervous system including the cardiac sympathetic nerve terminal disruption with norepinephrine seethe and spillover. PPGL-induced TS is characterized by a dramatic clinical presentation with hemodynamic compromise and high complication rates. The prevalence of global and apical sparing pattern of TS in PPGL-induced TS is significantly higher than in other TS populations. In this report, the associations of PPGL-induced cardiovascular complications are analyzed, and clinical features, complications, outcome and treatment of PPGL-induced TS are reviewed.

Fibrinolysis-treated myocardial infarction in a patient with missed spontaneous coronary artery dissection associated with takotsubo syndrome: case report

Background

Spontaneous coronary artery dissection (SCAD) is an under-recognized acute cardiac disease entity. It is often missed, or misdiagnosed as coronary spasm, coronary atherosclerotic lesion, or thrombotic coronary occlusion. During the last years, SCAD also has been reported to be 'misdiagnosed as takotsubo syndrome (TS)' in patients with features consistent with both conditions. Spontaneous coronary artery dissection may present as an acute coronary syndrome and sometimes as sudden cardiac death.

Case summary

We report on the case of a 67-year-old woman who presented with features of ST-elevation myocardial infarction treated with fibrinolysis. The patient showed to have obtuse-marginal SCAD, which was misdiagnosed as fibrinolysis caused lysis of a coronary thrombus. The patient had moreover all other features of TS.

Discussion

This case report teaches important information about SCAD. The association between SCAD and TS are discussed.

Frequency of Takotsubo Cardiomyopathy in Adult Patients Receiving Chemotherapy (from a 5-Year Nationwide Inpatient Study)

Takotsubo cardiomyopathy (TC) develops in patients who are under significant emotional, psychosocial, or sudden biochemical stress. However, the added burden of TC on the patients receiving chemotherapy has never been studied. We aimed to describe the additional clinical and economic burden, along with the potential predictors of TC and related in-hospital mortality in patients receiving chemotherapy using the largest inpatient cohort. We identified chemotherapy-related adult hospitalizations using the National Inpatient Sample databases (2010 to 2014). Primary end points were the incidence of TC and the odds of in-hospital mortality. Secondary end points were gender-based incidence differences, length of stay (LOS), hospital charges, and discharge disposition. We identified 1,067,977 chemotherapy-related hospitalizations, of which, 562 hospitalizations revealed TC incidence. Other co-morbidities were also significantly higher in the TC cohort. In unmatched analyses, the LOS (median 17 days vs 5 days) and total hospital charges (median $162,825 vs $46,335) were significantly higher in the TC group. A propensity-matched analysis confirmed the increased healthcare burden. Multivariate analysis revealed over 2-times higher odds (odds ratio [OR] 2.17) of in-hospital mortality in the TC group. Female gender (OR 2.48), and nonelective (OR 2.26), and nonfederal government hospital (OR 2.68) admissions had more than twice the odds of developing TC. An advanced age, Asian race, urban-teaching hospital, and complications such as septicemia, fluid-electrolyte disorders, cardiogenic shock, and respiratory failure independently raised mortality odds in the TC group. In conclusion, we observed an overall increasing nationwide trend in TC incidence in patients receiving chemotherapy, which adds to significantly increased in-hospital mortality, LOS, and healthcare charges.

Cardiogenic shock induced by Takotsubo cardiomyopathy in early postoperative adrenalectomy period

Takotsubo cardiomyopathy is part of the group of diseases called stress-induced cardiomyopathies. Its usual clinical presentation is indistinguishable from an acute coronary syndrome. However, early diagnosis is important, as it may debut as a cardiogenic shock in approximately 8% of cases, with morbidity and mortality rates comparable to those of acute coronary syndrome. For this reason, although it is a relatively infrequent condition, the perioperative period is a stress factor that can act as a trigger of this pathology. A case is presented of the onset of Takotsubo cardiomyopathy as a cardiogenic shock during admission in a Postoperative Recovery Unit.

Distinct Incidence of Takotsubo Syndrome Between Amyotrophic Lateral Sclerosis and Synucleinopathies: A Cohort Study

Takotsubo syndrome (TTS) is an acute cardiac syndrome characterized by regional left ventricular dysfunction with a peculiar circumferential pattern, which typically results in apical ballooning. Evidence indicates a pivotal role of catecholamines in TTS, and researchers have discussed multiple hypotheses on the etiology, including multivessel coronary spasm, myocardial stunning, excessive transient ventricular afterload, and cardiac sympathetic overactivity with local noradrenaline spillover. Although central nervous system disorders, such as stroke and epilepsy, are known to trigger TTS, the incidence and clinical features of TTS in neurodegenerative disorders are poorly understood. Here, we retrospectively examined TTS cases in a single-center cohort composed of 250 patients with amyotrophic lateral sclerosis (ALS) and 870 patients with synucleinopathies [582 patients with Parkinson's disease (PD), 125 patients with dementia with Lewy bodies (DLB), and 163 patients with multiple system atrophy (MSA)] and identified 4 (1.6%, including 2 women) cases with ALS and no cases with synucleinopathies. Two ALS patients underwent autopsy and the pathological findings were compatible with the chronological changes identified in catecholamine-induced cardiomyopathy. A literature review identified 16 TTS cases with ALS, 1 case each with PD and DLB, and no cases with MSA. When current and previous TTS cases with ALS were concatenated: 55% (11/20) were female; 35% (7/20) had a bulbar-onset and 45% (9/20) had a limb-onset; the mean age of TTS onset was 63.3 ± 9.0 years and the mean interval time from ALS onset to TTS development was 4.9 ± 3.0 years; no (0/16) patients developed TTS within 12 months after ALS onset; 50% (10/20) underwent artificial ventilations; the mortality was 17% (3/18); and most cases had precipitating factors, and TTS development was associated with gastrostomy, tracheostomy, or infections in 45% (9/20) of the patients. This study demonstrated that ALS is a considerable predisposing factor of TTS and that synucleinopathies rarely cause TTS. The distinct TTS incidence between ALS and synucleinopathies may be due to cardiac sympathetic overactivity in ALS and may also be affected by cardiac sympathetic denervation in synucleinopathies. Moreover, the etiology of TTS in ALS may be reasonably explained by the two-hit theory.

Artery of Percheron infarction results in severe bradycardia: A case report

Background:

The thalamus is normally supplied by each posterior cerebral artery (PCA). The artery of percheron is a variant of this anatomy as it arises as a single trunk unilaterally from the PCA to supply the thalamus bilaterally. Occlusion of this artery is rare, and the diagnosis is usually missed without obtaining an MRI.

Case Description:

We illustrate the case of a 68-year-old male who presented with coma, ocular gaze palsy, and severe bradycardia from bilateral thalamic nuclei and midbrain infarction, as described as an artery of Percheron infarction. The patient recovered neurologically under conservative treatment with a residual vertical diplopia from downward gaze palsy. He underwent cardiac pacer implantation for severe bradycardia at the end of his admission. The thalamic pathway associated with cardiac rhythm, especially the zona inserta, is discussed. Publications related to the artery of Percheron are reviewed.

Conclusion:

Coma and ocular gaze palsy are the most common presentations following thalamic and midbrain ischemia from artery of Percheron infarction. To our knowledge, only a single case of artery of Percheron infarction with severe bradycardia has been reported in the past. Our case attested the role of thalamic nuclei controlling cardiac rhythm.

Plasma Epinephrine Level and its Causal Link to Takotsubo Syndrome Revisited: Critical Review with a Diverse Conclusion

Takotsubo syndrome (TS) is a recognized acute cardiac syndrome with a clinical presentation resembling that of an acute coronary syndrome (ACS). The defining feature of TS is the reversible left ventricular wall motion abnormality (LVWMA), which has a unique circumferential pattern resulting in a conspicuous ballooning of the left ventricle during systole, and extending beyond the coronary artery supply territory. The pathogenesis of TS is still elusive and several pathophysiological mechanisms have been proposed. A common portrayal of the syndrome in the literature is that the disease is characterized by massive surge of plasma catecholamines including epinephrine. Based on the assumption of massive plasma epinephrine elevation, some investigators hypothesized that the circulatory plasma epinephrine plays a pivotal role in the pathogenesis of TS. One typical such hypothesis is epinephrine induced switch in signal trafficking causing apical or mid-apical ballooning in TS. In-depth analysis of the literature reveals that no study with certainty has shown "massive" plasma epinephrine elevations in TS. Furthermore, the literature evidences challenging the epinephrine-induced switch in signal trafficking are substantial. In this review, sufficient data, indicating that the plasma epinephrine in TS is either normal or moderately elevated in all studies, are provided. Noteworthy, epinephrine may act as a trigger factor for TS-induction but there is no evidence for a direct causal link between epinephrine and TS.

Spontaneous coronary artery dissection and takotsubo syndrome: An often overlooked association; review

Spontaneous coronary artery dissection (SCAD) and takotsubo syndrome (TS) are two cardiovascular syndromes with predilection for women. Both conditions may be preceded by an emotional stress or, for the affected individual, an unusual severe physical exercise. "Restitution ad integrum" occurs in most cases suffering from SCAD or TS with complete angiographic resolution of the dissected vessel and left ventricular dysfunction respectively. Recently, many cases, which were initially diagnosed as TS because of typical left ventricular ballooning pattern showed to have SCAD, have been reported; these cases were deemed to be "SCAD misdiagnosed as TS". The left ventricular wall motion abnormality has been attributed to the ischemia caused by SCAD-affected coronary vessel especially in the left anterior descending artery (LAD) with "wrap-around course". However, the left ventricular ballooning pattern have occurred in patients with SCAD in non-long-wrap-around LAD and SCAD in other coronary branches where coronary ischemia on its own cannot explain the left ventricular ballooning. In this review, sufficient data supporting the evidence for the possibility of coexistence of SCAD and TS is provided. Misdiagnosis of the association of the two conditions may result in mismanagement of the patient with undesirable consequences. Furthermore, the causal links between SCAD and TS is discussed.

Epidemiology, pathogenesis, and management of takotsubo syndrome

Takotsubo syndrome is a recently recognized acute cardiac disease entity with a clinical presentation resembling that of an acute coronary syndrome. The typical takotsubo syndrome patient has a unique circumferential left (bi-) ventricular contraction abnormality profile that extends beyond a coronary artery supply territory and appears to follow the anatomical cardiac sympathetic innervation. The syndrome predominantly affects postmenopausal women and is often preceded by emotional or physical stress. Patients with predisposing factors such as malignancy and other chronic comorbidities are more prone to suffer from takotsubo syndrome. The pathogenesis of takotsubo syndrome is elusive. Several pathophysiological mechanisms involving myocardial ischemia (multivessel coronary artery spasm, microvascular dysfunction, aborted myocardial infarction), left ventricular outlet tract obstruction, blood-borne catecholamine myocardial toxicity, epinephrine-induced switch in signal trafficking, and autonomic nervous system dysfunction have been proposed. The syndrome is usually reversible; nevertheless, during the acute stage, a substantial number of patients develop severe complications such as arrhythmias, heart failure including pulmonary edema and cardiogenic shock, thromboembolism, cardiac arrest, and rupture. Treatment of precipitating factors, predisposing diseases, and complications is fundamental during the acute stage of the disease. The epidemiology, pathogenesis, and management of takotsubo syndrome are reviewed in this paper.

Takotsubo syndrome

Takotsubo syndrome is a reversible acute heart failure frequently precipitated by an emotional or physical stress. The clinical presentation resembles acute coronary syndrome. Pathogenesis is complex and may involve brain-heart axis and neuro-hormonal stunning of the myocardium. Coronary angiography reveals normal epicardial arteries with no obstruction or spasm. NT-ProBNP maybe remarkably elevated. Regional wall motion akinesia (RWMA) of left ventricle extends beyond the territory of one coronary artery. Reduced left ventricle ejection fraction (LVEF) and RWMA recover in 6-12 weeks. Prognosis is generally good. Recent meta-analysis shows in-hospital mortality of 1-4.5% and recurrence rate of 5-10% during five year follow-up.

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.

A Review of Neurogenic Stunned Myocardium

Neurologic stunned myocardium (NSM) is a phenomenon where neurologic events give rise to cardiac abnormalities. Neurologic events like stroke and seizures cause sympathetic storm and autonomic dysregulation that result in myocardial injury. The clinical presentation can involve troponin elevation, left ventricular dysfunction, and ECG changes. These findings are similar to Takotsubo cardiomyopathy and acute coronary syndrome. It is difficult to distinguish NSM from acute coronary syndrome based on clinical presentation alone. Because of this difficulty, a patient with NSM who is at high risk for coronary heart disease may undergo cardiac catheterization to rule out coronary artery disease. The objective of this review of literature is to enhance physician's awareness of NSM and its features to help tailor management according to the patient's clinical profile.

Inflammatory Cell Findings in the Female Rabbit Heart and Stress-associated Exacerbation with Handling and Procedures Used in Nonclinical Studies

Despite the use of rabbits in biomedical research, including regulatory toxicology and cardiovascular studies, little data exist on heart findings in this species. This study was designed to document myocardial findings in female rabbits and the impact of study-related procedures typical for vaccine toxicology studies. One hundred and forty 6- to 8-month-old female New Zealand White rabbits were divided equally into 2 groups, high and low study procedure groups (group 1 and group 2, respectively). All animals received intramuscular (IM) injections of sterile saline every 2 weeks for 5 times and were necropsied 2 days after the final IM injection. Clinical chemistry, hematology, and urinalysis were evaluated. Blood for stress biomarkers (norepinephrine, epinephrine, cortisol, and corticosterone), C-reactive protein, cardiac troponin I, and creatine kinase were collected at time 0 (just before dose administration) and then at 4, 24, and 48 hr after dose administration in group 1 only. Hearts were assessed histologically. Focal to multifocal minimal inflammatory cell infiltrates were common (∼80%), particularly in the left ventricle and interventricular septum, and were similar to the types of infiltrates identified in other laboratory animal species. Additionally, study-related procedures elevated serum stress biomarkers and exacerbated the frequency and severity of myocardial inflammatory cell infiltrates.

The natural history of takotsubo syndrome: a two-year follow-up study with myocardial sympathetic and perfusion G-SPECT imaging

PURPOSE

To investigate changes in sympathetic activity, perfusion, and left ventricular (LV) functionality in takotsubo cardiomyopathy (TTC) patients from onset (T₀) to post-onset conditions at 1 month (T₁), 1-2 years (T₂, T₃).

METHODS

Twenty-two patients (70 ± 11 years) underwent serial gated single photon emission tomography (G-SPECT) studies with ¹²³I-mIBG and ^99mTc-Sestamibi. Statistics were performed using ANOVA/Sheffé post-hoc, correlation test, and receiver operating characteristic (ROC) curve analysis (p < 0.05).

RESULTS

Patients presented at T₀ with LV ballooning and reduced early-late mIBG uptake (95%, 100%), left ventricular ejection fraction (LVEF)_G-SPECT (86%) and perfusion (77 %). Adrenergic dysfunction was greater in apex, it overlaps with contractile impairment, and both were more severe than perfusion defect. During follow-up, LVEF_G-SPECT, contractility, and perfusion were normal, while 82% and 90% of patients at T₁ and 50% at T₂ and T₃ continued to show a reduced apical early-late mIBG distribution. These patients presented at T₀-T₁ with greater impairment of adrenergic function, contractility, and perfusion. A relationship was present within innervation and both perfusion and contractile parameters at T₀ and T₁, and between the extent of adrenergic defect at T₃ and both the defect extent and age at T₀ (cut-off point 42.5%, 72 years).

CONCLUSION

Outcome for TTC is not limited to a reversible contractile and perfusion abnormalities, but it includes residual adrenergic dysfunction, depending on the level of adrenergic impairment and age of patients at onset. The number of patients, as well as degree of perfusion abnormalities were found to be higher than those previously reported possibly depending on the time-interval between hospital admission and perfusion scan.

Contemporary review on the pathogenesis of takotsubo syndrome: The heart shedding tears: Norepinephrine churn and foam at the cardiac sympathetic nerve terminals

Takotsubo syndrome (TS), an increasingly recognized acute cardiac disease entity, is characterized by a unique pattern of circumferential and typically regional left ventricular wall motion abnormality resulting in a conspicuous transient ballooning of the left ventricle during systole. The mechanism of the disease remains elusive. However, the sudden onset of acute myocardial stunning in a systematic pattern extending beyond a coronary artery territory; the history of a preceding emotional or physical stress factor in two thirds of cases; the signs of sympathetic denervation at the regions of left ventricular dysfunction on sympathetic scintigraphy; the finding of myocardial edema and other signs consistent with (catecholamine-induced) myocarditis shown by cardiac magnetic resonance imaging; and the contraction band necrosis on histopathological examination all argue strongly for the involvement of the cardiac sympathetic nervous system in the pathogenesis of TS. In this narrative review, extensive evidence in support of local cardiac sympathetic nerve hyperactivation, disruption and norepinephrine spillover causing TS in predisposed patients is provided.

Dopamine induces lipid accumulation, NADPH oxidase-related oxidative stress, and a proinflammatory status of the plasma membrane in H9c2 cells

Excess catecholamine levels are suggested to be cardiotoxic and to underlie stress-induced heart failure. The cardiotoxic effects of norepinephrine and epinephrine are well recognized. However, although cardiac and circulating dopamine levels are also increased in stress cardiomyopathy patients, knowledge regarding putative toxic effects of excess dopamine levels on cardiomyocytes is scarce. We now studied the effects of elevated dopamine levels in H9c2 cardiomyoblasts. H9c2 cells were cultured and treated with dopamine (200 μM) for 6, 24, and 48 h. Subsequently, the effects on lipid accumulation, cell viability, flippase activity, reactive oxygen species (ROS) production, subcellular NADPH oxidase (NOX) protein expression, and ATP/ADP and GTP/GDP levels were analyzed. Dopamine did not result in cytotoxic effects after 6 h. However, after 24 and 48 h dopamine treatment induced a significant increase in lipid accumulation, nitrotyrosine levels, indicative of ROS production, and cell death. In addition, dopamine significantly reduced flippase activity and ATP/GTP levels, coinciding with phosphatidylserine exposure on the outer plasma membrane. Furthermore, dopamine induced a transient increase in cytoplasmic and (peri)nucleus NOX1 and NOX4 expression after 24 h that subsided after 48 h. Moreover, while dopamine induced a similar transient increase in cytoplasmic NOX2 and p47^phox expression, in the (peri)nucleus this increased expression persisted for 48 h where it colocalized with ROS. Exposure of H9c2 cells to elevated dopamine levels induced lipid accumulation, oxidative stress, and a proinflammatory status of the plasma membrane. This can, in part, explain the inflammatory response in patients with stress-induced heart failure.

Acute, repetitive and chronic Takotsubo syndrome in patients with chronic kidney disease: Sympathetic reno-cardial syndrome

Heart failure and cardiovascular death are common in patients with chronic kidney disease (CKD) and extremely prevalent in patients undergoing dialysis. It has been shown that the excess of cardiovascular mortality in this patient population is not fully accounted for by the traditional cardiovascular risk factors. Substantial evidence exists for the presence of sympathetic over-activity in patients with dialytic and non-dialytic CKD. Several studies have also been reported on reversible segmental left ventricular wall motion abnormality consistent with myocardial stunning in association with dialysis especially hemodialysis. In the literature, the most acceptable underpinning hypothesis for the myocardial stunning in CKD is "demand myocardial ischemia". However, the occurrence of cardiac sympathetic over-activation-disruption and repeated reversible myocardial stunning in patients with CKD can be compared to that occurring in acute Takotsubo syndrome where local cardiac sympathetic disruption may cause acute regional circumferential pattern of myocardial stunning. In this manuscript, converging evidences suggestive for the fact that acute, repetitive, and chronic TS may be one of the important causes of cardiac morbidity including myocardial stunning and heart failure and mortality in patients with CKD are provided.

Clinical features and outcome of epinephrine-induced takotsubo syndrome: Analysis of 33 published cases

BACKGROUND

Takotsubo syndrome (TS) may be triggered by innumerable physical stress factors including epinephrine administration. The aim of this study is to report on the clinical features and outcome of epinephrine-induced TS (Epi-TS) in a large cohort of published cases.

METHODS

A computer assisted search of the electronic data base Pubmed was performed from 1990 to 2014. All cases deemed to have Epi-TS were retrieved and compared to the large recent report by Templin et al. (All-TS).

RESULTS

Thirty-three cases of Epi-TS were retrieved from the literature and compared to 1750 cases of All-TS. Chest pain as a presenting symptom occurred in 45% of cases. The Epi-TS patients were on average 20.6years younger than All-TS patients (p<0.0001). The women were still predominating in Epi-TS but in a significantly lower percentage compared to ALL-TS (73% in Epi-TS vs 89.8% in All-TS, p=0.0054). One third of the Epi-TS cases had basal pattern of TS compared to 2.2% of cases reported in All-TS. Epi-TS cases were characterized by high complication rates, which occurred in 57.6%. The most important risk factor for the development of TS complication was the accidental administration (P<0.001) and the dose of >1mg epinephrine (p=0.02). In spite of high complication rates, the recovery was rapid with no in-hospital mortality.

CONCLUSION

Epi-TS is characterized by a dramatic rapid onset of symptoms after epinephrine administration. Almost half of the cases had apical sparing and one third basal pattern of TS. In spite of high complication rates, the prognosis was good with no in-hospital mortality.

Clinical Features and Outcome of Pheochromocytoma-Induced Takotsubo Syndrome: Analysis of 80 Published Cases

Myriads of physical stress factors including pheochromocytoma have been reported triggering takotsubo syndrome (TS). The aim of this study was to report on the clinical features and outcome of pheochromocytoma-induced TS (Pheo-TS) in a large cohort of patients. Eighty published cases of Pheo-TS were retrieved from the literature and compared with 1,750 cases of all patients with TS (All-TS) published recently by Templin et al. Patients with Pheo-TS were on average 19.87 years younger than those with All-TS (p <0.0001). The women were still predominating in Pheo-TS but significantly in a lower percentage (70% in Pheo-TS vs 89.8% in All-TS, p <0.00001). Almost 1/3 (30%) of Pheo-TS cases had basal TS pattern compared with 2.2% of cases in All-TS (p <0.00001) and 1/5 (20%) had global TS compared with no cases in All-TS. Two thirds of Pheo-TS cases (67.9%) developed complications, which was significantly higher than complication rates in All-TS (21.8%), but there was no difference in the inhospital mortality between the 2 studies. The most important risk factors for the development of complications in Pheo-TS were age <50 years and global and basal TS localization patterns. The recurrence rate of 17.7% in Pheo-TS was significantly higher than the 3.26% in All-TS (p <0.00001). In conclusion, Pheo-TS is characterized by a dramatic clinical presentation with high complication rates and relatively high recurrence rate. Patients with Pheo-TS are significantly younger than All-TS. The TS localization pattern in Pheo-TS differed significantly from All-TS with basal pattern in almost 1/3 of cases and global pattern in 1/5 of the cases.

Role of Coronary Microvascular Dysfunction in Takotsubo Cardiomyopathy

Takotsubo cardiomyopathy (TTC) is a relatively frequent acute cardiac condition, but its pathogenesis has not been established as yet. Since the first descriptions of TTC, microvascular dysfunction has been advocated as a possible pathophysiological mechanism underlying the left ventricular wall motion abnormalities that characterize the syndrome. Several noninvasive and invasive methods have confirmed the involvement of coronary microvascular abnormalities in the pathogenesis of TTC, but whether microvascular dysfunction is the primary cause or a secondary phenomenon is still debated. The greater prevalence of TTC among postmenopausal women, along with the relationship identified between physical and emotional triggers and other "neuro-cardiac" mechanisms, suggest that increased microvascular reactivity, possibly sympathetically mediated, may play a pathogenic role in susceptible individuals. This review critically evaluates the possible role of microvascular dysfunction in the development of TTC.

Anxiety as a risk factor in cardiovascular disease

PURPOSE OF REVIEW

The narrative review covers recent studies of anxiety as a companion in cardiovascular disease.

RECENT FINDINGS

Prospective population-based studies and studies of cases with known cardiovascular disease have been conducted, as well as studies of intervention with coronary bypass grafting, heart transplants, and implantable cardioverter-defibrillators, and subsequent rehabilitation programs. Mental stress-induced myocardial ischemia (MSIMI) stands for this emerging research arena.

SUMMARY

Anxiety has emerged as perhaps the most important risk factor for cardiovascular disease, determining other known risk factors, such as depression, substance use, overweight, and a sedentary lifestyle. Anxiety also increases the risk of major cardiac events in coronary heart disease. There is a need for elucidating the influence of anxiety in takotsubo and in white-coat hypertension. Managing anxiety is of vital importance in patients who have received heart transplants, to ascertain adherence to immunosuppressants.

Prevalence of Myocardial Bridging in Patients With Myocardial Infarction and Nonobstructed Coronary Arteries

Mechanisms of acute myocardial infarction and nonobstructed coronary arteries (MINOCA) are incompletely understood. Myocardial bridging (MB) is usually considered a benign congenital variant, but serious complications have been reported. MB has also been proposed as a cause of takotsubo syndrome (TS). We aimed to examine whether MB was more frequent in patients with MINOCA or TS than in age- and gender-matched controls and to compare the MB detection rates of coronary computed tomography angiography (CTA) and invasive coronary angiography (ICA). Patients with MINOCA (n = 57) and age- and gender-matched controls (n = 58), aged 45 to 70 were enrolled. Myocarditis was excluded by cardiovascular magnetic resonance imaging. Patients with TS (n = 15) were considered as a subgroup and therefore not excluded. Patients with MINOCA underwent ICA and all study participants underwent coronary CTA. All examinations were reviewed with focus on MB. Among 57 MINOCA patients, 15 MINOCA patients with TS and 58 controls, MB was demonstrated in 28 patients (49%), 8 patients (53%), and 26 patients (45%), respectively. There were no statistically significant differences regarding the prevalence of MB or the type, location, length, or thickness of MB. There was a statistically significant difference (p <0.01) between the detection rates of coronary CTA and ICA that demonstrated MB in 54 subjects (47%) and 13 subjects (23%), respectively. In conclusion, MB was frequent with a similar prevalence in patients with MINOCA, patients with TS and controls. This suggests that there is no causal link between MB and MINOCA or TS. Furthermore, coronary CTA detects MB at a significantly higher rate than ICA.

Comorbidities frequency in Takotsubo syndrome: an international collaborative systematic review including 1109 patients

BACKGROUND

To identify predisposing factors that can result in the onset of takotsubo syndrome, we performed an international, collaborative systematic review focusing on clinical characteristics and comorbidities of patients with takotsubo syndrome.

METHODS

We searched and reviewed cited references up to August 2013 to identify relevant studies. Corresponding authors of selected studies were contacted and asked to provide additional quantitative details. Data from each study were extracted by 2 independent reviewers. The cumulative prevalence of presenting features and comorbidities was assessed. Nineteen studies whose authors sent the requested information were included in the systematic review, with a total of 1109 patients (951 women; mean age, 59-76 years). Evaluation of risk factors showed that obesity was present in 17% of patients (range, 2%-48%), hypertension in 54% (range, 27%-83%), dyslipidemia in 32% (range, 7%-59%), diabetes in 17% (range, 4%-34%), and smoking in 22% (range, 6%-49%). Emotional stressors preceded takotsubo syndrome in 39% of patients and physical stressors in 35%. The most common comorbidities were psychological disorders (24%; range, 0-49%), pulmonary diseases (15%; range, 0-22%), and malignancies (10%; range, 4%-29%). Other common associated disorders were neurologic diseases (7%; range, 0-22%), chronic kidney disease (7%; range, 2%-27%), and thyroid diseases (6%; range, 0-37%).

CONCLUSIONS

Patients with takotsubo syndrome have a relevant prevalence of cardiovascular risk factors and associated comorbidities. Such of associations needs to be evaluated in further studies.

The pathogenesis of reversible T-wave inversions or large upright peaked T-waves: Sympathetic T-waves

Reversible electrocardiographic (ECG) repolarization changes including T-wave inversions (TWI), large upright peaked T-waves (LUPTW) and prolongation of the corrected QT interval (P-QTc) have been reported in association with myriads of acute cardiac and non-cardiac diseases. Through the last 70 years, the TWIs have been described under different terms as; cerebral, giant, global, canyon, Wellens or coronary and cardiac memory T waves. During the last 15 years, the reversible TWI and LUPTW in association with P-QTc have been described as characteristic ECG features in takotsubo syndrome (TS), which also may be triggered by the same aforementioned acute cardiac and non-cardiac disease entities. The pathogenesis of these reversible T-wave changes is not clear-cut. In this manuscript, substantial evidences for a causal link between the local cardiac sympathetic disruption and the development of the reversible TWI and LUPTW are presented. As a result, a pathogenetic term for the reversible TWI or LUPTW, which is sympathetic T waves (sympathetic TWI or sympathetic LUPTW), would be the most appropriate term.

Takotsubo cardiomyopathy case series: typical, atypical and recurrence

Takotsubo cardiomyopathy (TCM) is characterised by a transient left ventricular (LV) dysfunction, ECG changes that can imitate acute myocardial infarction and positive cardiac biomarkers in the absence of obstructive coronary artery disease. The exact pathogenesis of TCM is unclear but emotional or physical stress is a common denominator. We present three cases encompassing a spectrum of the disease: A typical TCM with apical LV dyskinesis, an atypical TCM with mid-ventricular regions affected and a TCM recurrence. Our cases show that TCM symptoms vary between individuals and may vary in the same patient. All our patients reported acute emotional stress prior to the onset of symptoms, had LV systolic dysfunction, positive cardiac biomarkers and non-obstructed coronary arteries. In all cases, LV systolic dysfunction eventually improved. TCM may account for 0.7-2.5% of acute coronary syndromes. It is more prevalent in the female population and can reoccur. Treatment is mainly supportive.

Acute cardiac sympathetic disruption and left ventricular wall motion abnormality in takotsubo syndrome

Takotsubo syndrome (TS) is characterized by a unique pattern of transient circumferential left ventricular wall motion abnormality (LVWMA). The LVWMA in TS may be localized to the apical, mid-apical, mid-ventricular, mid-basal or basal regions of the left ventricle. Focal and generialized (global) LVWMA have also been reported. In the acute phase of TS, the hyperkinetic valve-like motion of the basal segments and/or the hyperkinetic slingshot-like motion of the apical segments combined with the firm stunned a-, hypokinetic segments result in a conspicuous left ventricular ballooning during systole. The LVWMA in TS follows most probably the local cardiac sympathetic nerve distribution and caused by local cardiac sympathetic disruption and noradrenaline spillover.

Low prevalence of diabetes mellitus in patients with Takotsubo syndrome: A plausible 'protective' effect with pathophysiologic connotations

AIMS

The pathophysiology of Takotsubo syndrome is still elusive; coronary vasospasm, microvascular dysfunction, or catecholamine-mediated injury to the cardiomyocytes, effected by local release from the autonomic nerves and/or blood-borne catecholamines, are considered as tentative cause(s). Diabetes mellitus-induced autonomic neuropathy leads to a brain-heart disconnection, and it can conceivably ameliorate/block the effect of an unbridled adrenergic storm to the heart, and the emergence of Takotsubo syndrome. This study sought to evaluate the prevalence of diabetes mellitus in patients with Takotsubo syndrome.

METHODS AND RESULTS

All the papers accessed in PubMed were reviewed, to evaluate the prevalence of diabetes mellitus and hypertension in Takotsubo syndrome patients, employing the rate of the latter as an index of how representative of the general population were the study patients, and the rate of the former as the focus of this investigation. Out of the 1932 papers, 959 were suitable for analysis, reporting on 33,894 patients (88.9% women) with Takotsubo syndrome. In five subanalyses, of all patients, patients reported individually, patients reported collectively in case series, patients ⩾ 60 years old reported individually, and patients ⩾ 65 years old reported individually, the prevalence of hypertension was 57.4%, 42.8%, 57.9%, 50.4%, and 52.2%, correspondingly, and comparable to the 65.4% shown by the National Health and Nutrition Examination Survey (NHANES). The prevalence of diabetes mellitus in the five subgroups was 16.8%, 10.2%, 17.0%, 11.9%, and 12.5%, correspondingly, and lower than the 26.9% found by the NHANES.

CONCLUSION

The prevalence of diabetes mellitus in patients with Takotsubo syndrome is low. This insight may be useful for the diagnosis, pathophysiology unraveling, and employment of autonomic adrenergic blocking agents in the management of patients with Takotsubo syndrome.