Autonomic nervous system in Takotsubo syndrome

Inflammatory Forms of Cardiomyocyte Cell Death in the Rat Model of Isoprenaline-Induced Takotsubo Syndrome

Takotsubo syndrome (TTS) is associated with inflammatory response, therefore the aim of the study was to evaluate the presence and dynamics of inflammatory-associated forms of cell death, necroptosis, and pyroptosis in the female rat model of isoprenaline (ISO)-induced TTS. TTS was induced in female Sprague Dawley rats (n = 36) by ISO 150 mg/kg intraperitoneally. Animals were divided into four groups: TTSO (TTS+ovariectomy; n = 10), TTSP (TTS+sham operation; n = 10), CO (0.9% NaCl+ovariectomy; n = 8), CP (0.9% NaCl+sham operation; n = 8). Histopathological analysis, evaluation of plasma concentration, and myocardial expression of pyroptosis- and necroptosis-associated proteins were performed. TTSO and TTSP groups had higher plasma concentrations of interleukin-1β in comparison with the controls. Low myocardial protein expression of mixed lineage kinase domain-like pseudokinase (MLKL), caspase-1 (Casp-1), and calcium/calmodulin-dependent kinase type II isoform delta (CAMKIIδ) was visible 6 and/or 12 h post-ISO. Twenty-four hours post-ISO, high myocardial and vascular protein expression of CAMKIIδ was visible in TTSO but not TTSP rats, while high myocardial expression of MLKL and Casp-1 was visible both in TTSO and TTSP rats. The course of TTS is associated with activation of inflammatory-associated programmed cell death, necroptosis, and pyroptosis, therefore inflammation may be a primary response occurring simultaneously with cardiomyocyte death in TTS.

Orexin/hypocretin system dysfunction in patients with Takotsubo syndrome: A novel pathophysiological explanation

Takotsubo syndrome (TTS) is an acute heart failure syndrome. Emotional or physical stressors are believed to precipitate TTS, while the pathophysiological mechanism is not yet completely understood. During the coronavirus disease (COVID-19) pandemic, an increased incidence of TTS has been reported in some countries; however, the precise pathophysiological mechanism for developing TTS with acute COVID-19 infection is unknown. Nevertheless, observing the symptoms of COVID-19 might lead to new perspectives in understanding TTS pathophysiology, as some of the symptoms of the COVID-19 infection could be assessed in the context of an orexin/hypocretin-system dysfunction. Orexin/hypocretin is a cardiorespiratory neuromodulator that acts on two orexin receptors widely distributed in the brain and peripheral tissues. In COVID-19 patients, autoantibodies against one of these orexin receptors have been reported. Orexin-system dysfunction affects a variety of systems in an organism. Here, we review the influence of orexin-system dysfunction on the cardiovascular system to propose its connection with TTS. We propose that orexin-system dysfunction is a potential novel explanation for the pathophysiology of TTS due to direct or indirect dynamics of orexin signaling, which could influence cardiac contractility. This is in line with the conceptualization of TTS as a cardiovascular syndrome rather than merely a cardiac abnormality or cardiomyopathy. To the best of our knowledge, this is the first publication to present a plausible connection between TTS and orexin-system dysfunction. We hope that this novel hypothesis will inspire comprehensive studies regarding orexin's role in TTS pathophysiology. Furthermore, confirmation of this plausible pathophysiological mechanism could contribute to the development of orexin-based therapeutics in the treatment and prevention of TTS.

Imaging of heart disease in women: review and case presentation

Cardiovascular diseases (CVD) remain the leading cause of mortality worldwide. Although major diagnostic and therapeutic advances have significantly improved the prognosis of patients with CVD in the past decades, these advances have less benefited women than age-matched men. Noninvasive cardiac imaging plays a key role in the diagnosis of CVD. Despite shared imaging features and strategies between both sexes, there are critical sex disparities that warrant careful consideration, related to the selection of the most suited imaging techniques, to technical limitations, and to specific diseases that are overrepresented in the female population. Taking these sex disparities into consideration holds promise to improve management and alleviate the burden of CVD in women. In this review, we summarize the specific features of cardiac imaging in four of the most common presentations of CVD in the female population including coronary artery disease, heart failure, pregnancy complications, and heart disease in oncology, thereby highlighting contemporary strengths and limitations. We further propose diagnostic algorithms tailored to women that might help in selecting the most appropriate imaging modality.

The Brain-Heart Connection in Takotsubo Syndrome: The Central Nervous System, Sympathetic Nervous System, and Catecholamine Overload

Takotsubo syndrome (TTS), also known as stress cardiomyopathy, is a type of acute heart failure syndrome triggered by intense psychological or physiological stress. TTS typically manifests as acute chest pain, dyspnea or syncope that mimics an acute myocardial infarction but does not involve coronary artery obstruction. The current understanding of the pathogenesis of TTS suggests that sympathetic nervous system (SNS) activation plays a central role. Specifically, stress can activate the SNS and lead to the over-release of catecholamine, which have toxic effects on myocardial tissue when present at excessive levels. However, the brain changes associated with TTS and the connection between the brain and the heart in patients with this disease remain unclear. In recent years, several published reports have revealed the role of this brain-heart connection in the pathogenesis of TTS. This review summarizes recent studies regarding SNS activation, catecholamine overload, and the brain-heart connection in patients with TTS from both pathophysiological and mechanistic aspects.

Simultaneous transient global amnesia and Takotsubo syndrome after death of a relative: a case report

Introduction

Simultaneous occurrence of transient global amnesia and Takotsubo syndrome has been only rarely reported. Here we report another patient with a transient global amnesia and concomitant Takotsubo syndrome.

Case presentation

Our patient is a 64-year-old white man with a previous history of myocarditis from borreliosis who developed sudden-onset confusional state with perseverations and repetition of the same questions during a funeral for his brother-in-law. Upon neurological work-up and after spontaneous resolution of most of the neurological deficits, transient global amnesia was diagnosed. Blood tests revealed moderate renal insufficiency, elevated troponin-T, and elevated N-terminal prohormone of brain natriuretic peptide. Electrocardiography showed left anterior hemiblock and negative T-waves in V2–V6. Upon transthoracic echocardiography the apical type of a Takotsubo syndrome was suspected. Since coronary angiography was normal and electrocardiography and echocardiographic abnormalities resolved under candesartan, bisoprolol, acetyl-salicylic acid, and atorvastatin within a few days after onset, Takotsubo syndrome was diagnosed.

Conclusions

Since Takotsubo syndrome may be associated with transient global amnesia a causal relation may exist. A possible trigger for both conditions could be severe emotional stress from the loss of a close relative. A possible common pathomechanism could be overstimulation of adrenergic receptors in the myocardium, the cerebrum, or the coronary or cerebral arteries. Whether pre-existing myocardial compromise promotes the development of Takotsubo syndrome requires further investigations.