Sympathetic nervous activity and myocardial damage immediately after subarachnoid hemorrhage in a unique animal model

Troponin I as a Predictor of Transcranial Doppler Sonography Defined Vasospasm in Intensive Care Unit Patients After Spontaneous Subarachnoid Hemorrhage

OBJECTIVE

Elevation of Troponin I (TnI) in spontaneous subarachnoid hemorrhage (SAH) patients is a well-known phenomenon and associated with cardiopulmonary complications and poor outcome. The present study was conducted to investigate the association of the TnI value on admission, and the occurrence of cerebral vasospam in SAH patients.

PATIENTS AND METHODS

A total of 142 patients with SAH, who were admitted to the neurosurgical intensive care unit (ICU) between December 2014 and January 2021 were evaluated. Blood samples were drawn on admission to determine TnI value. Each patient's demographic, radiological and medical data on admission, the modified Ranking Scale score at discharge as well as continuous measurements of transcranial Doppler sonography were analyzed. A maximum mean flow velocity (MMFV) > 120 cm/sec was defined as any vasospasm. These were stratified into severe vasospasms, which were defined as at least two measurements of MMFVs > 200 cm/sec or an increase of MMFV > 50 cm/sec/24 h over two consecutive days or a new neurological deterioration and mild vasospasm defined as MMFVs > 120 cm/sec in absence of severe vasospasm criteria. The total study population was dichotomized into patients with an initially elevated TnI (>0.05 µg/L) and without elevated TnI (≤0.05 μg/L).

RESULTS

A total of 52 patients (36.6%) had an elevated TnI level upon admission, which was significantly associated with lower GCS score (p < 0.001), higher WFNS score (p < 0.001) and higher Fisher grade (p = 0.01) on admission. In this context a higher rate of ischemic brain lesions (p = 0.02), a higher modified Rankin Scale score (p > 0.001) and increased mortality (p = 0.02) at discharge were observed in this group. In addition, TnI was identified as an independent predictor for the occurrence of any vasospasm and severe vasospasm.

CONCLUSION

An initially elevated TnI level is an independent predictor for the occurrence of any and severe vasospasm in patients with SAH.

The Role of Serum Monocytes and Tissue Macrophages in Driving Left Ventricular Systolic Dysfunction and Cardiac Inflammation Following Subarachnoid Hemorrhage

BACKGROUND

Neurocardiogenic injury is common after aneurysmal subarachnoid hemorrhage (aSAH) despite low prevalence of preexisting cardiac disease. Potential mechanisms include autonomic dysregulation due to excess catecholamines as well as systemic inflammation. Understanding how inflammation contributes to cardiac dysfunction may aid in identifying novel therapeutic strategies. Here, we investigated serum leukocytes as predictors of left ventricular systolic dysfunction in patients with aSAH. We also investigated increased cardiac macrophages in an animal model of SAH and whether immunomodulatory treatment could attenuate this inflammatory response.

METHODS

We retrospectively analyzed 256 patients with aSAH admitted to University of Illinois Hospital between 2013 and 2019. Our inclusion criteria included patients with aSAH receiving an echocardiogram within 72 h of admission. Our primary outcome was echocardiographic evidence of systolic dysfunction. We performed multinomial regression and receiver operating curve analysis. We also used the endovascular perforation model of SAH in male Sprague-Dawley rats to assess for myocardial inflammation. Two days after surgery, hearts were collected and stained for the macrophage marker Iba-1. We compared the presence and morphology of macrophages in cardiac tissue isolated from SAH animals and sham controls treated with and without the immunomodulatory agent fingolimod.

RESULTS

Of 256 patients with aSAH, 233 (91.0%) underwent echocardiography within 72 h of admission. Of 233, 81 (34.7%) had systolic dysfunction. Patients had baseline differences in the presence of hypertension, alcohol use, and admission Glasgow Coma Scale and Hunt-Hess score. On multivariable analysis, total leukocytes (odds ratio 1.312, p < 0.001), neutrophils (odds ratio 1.242, p = 0.012), and monocytes (odds ratio 6.112, p = 0.008) were independent predictors of reduced systolic function, whereas only monocytes (odds ratio 28.014, p = 0.030) predicted hyperdynamic function. Within the rodent heart, there were increased macrophages after SAH relative to controls, and this was attenuated by fingolimod treatment (p < 0.0001).

CONCLUSIONS

Increased serum leukocytes are associated with abnormal left ventricular systolic function following aSAH. The strongest independent predictor of both reduced and hyperdynamic systolic function was increased monocytes. Increased cardiac macrophages after experimental SAH can also be targeted by using immunomodulatory drugs.

Clinical Potential of Immunotherapies in Subarachnoid Hemorrhage Treatment: Mechanistic Dissection of Innate and Adaptive Immune Responses

Subarachnoid hemorrhage (SAH), classified as a medical emergency, is a devastating and severe subtype of stroke. SAH induces an immune response, which further triggers brain injury; however, the underlying mechanisms need to be further elucidated. The current research is predominantly focused on the production of specific subtypes of immune cells, especially innate immune cells, post-SAH onset. Increasing evidence suggests the critical role of immune responses in SAH pathophysiology; however, studies on the role and clinical significance of adaptive immunity post-SAH are limited. In this present study, we briefly review the mechanistic dissection of innate and adaptive immune responses post-SAH. Additionally, we summarized the experimental studies and clinical trials of immunotherapies for SAH treatment, which may form the basis for the development of improved therapeutic approaches for the clinical management of SAH in the future.

Alpha-methyltyrosine reduces the acute cardiovascular and behavioral sequelae in a murine model of traumatic brain injury

BACKGROUND

Increased catecholamines contribute to heightened cardiovascular reactivity and behavioral deficits after traumatic brain injury (TBI); adrenergic receptor blockade has limited success in reducing adverse sequelae of TBI. Injury-induced increases in the synthesis of catecholamines could contribute to adverse outcomes in TBI. Inhibition of catecholamine synthesis with alpha-methyltyrosine (αMT) could offer a benefit after TBI.

METHODS

Original research trial in mice randomized to αMT (50 mg·kg -1 ·d -1 ) or vehicle for 1 week after TBI induced by controlled cortical impact. Primary outcomes of cardiovascular reactivity and behavioral deficits were assessed after 1 week. Secondary outcomes included blood brain barrier permeability and quantification of gene transcription whose products determine intraneuronal chloride concentrations, the release of catecholamines, and activation of the sympathetic nervous system. These genes were the alpha-2 adrenergic receptor ("Adra2c"), the sodium-potassium-chloride cotransporter ("Nkcc1"), and the potassium chloride cotransporter ("Kcc2"). We also assessed the effect of TBI and αMT on the neuronal chloride/bicarbonate exchanger ("Ae3").

RESULTS

Traumatic brain injury-induced increases in blood pressure and cardiac reactivity were blocked by αMT. Inhibition of catecholamine synthesis decreased blood brain barrier leakage and improved behavioral outcomes after TBI. Traumatic brain injury diminished the transcription of Adra2c and enhanced expression of Nkcc1 while reducing Kcc2 transcription; αMT prevented the induction of the Nkcc1 by TBI without reversing the effects of TBI on Kcc2 expression; αMT also diminished Ae3 transcription.

CONCLUSION

Traumatic brain injury acutely increases cardiovascular reactivity and induces behavioral deficits in an αMT-sensitive manner, most likely by inducing Nkcc1 gene transcription. Alpha-methyltyrosine may prove salutary in the treatment of TBI by attenuating the enhanced expression of Nkcc1, minimizing blood brain barrier leakage, and diminishing central catecholamine and sympathetic output. We also found an unreported relationship between Kcc2 and the chloride/bicarbonate exchanger, which should be considered in the design of trials planned to manipulate central intraneuronal chloride concentrations following acute brain injury.

Stroke-heart syndrome: A case report and mini literature review

Despite the fact that cardiac troponin (cTn) elevation is commonly seen in the acute phase of ischemic stroke, investigating its etiology represents a challenge for healthcare practitioners. Therefore, we describe the case of an 86-year-old woman with dyspnea and cTn-elevation within the first days following acute ischemic stroke and discuss potential differential diagnoses and diagnostic dilemmas.

Takotsubo Cardiomyopathy in a Polytrauma Patient With Subarachnoid Hemorrhage

Takotsubo cardiomyopathy (TCM) is a sudden, transient myocardial stunning precipitated by severe emotional or physical stress. It is characterized by left ventricular apical ballooning and elevated cardiac enzymes without significant coronary artery stenosis. Stress-induced catecholamine surge has been proposed to be the likely mechanism of TCM. We report the case of a 23-year-old female who presented to the emergency department unconscious and in respiratory distress following a motor vehicle accident. The point-of-care ultrasonography showed prominent B lines in bilateral lung fields and a dilated inferior vena cava (IVC). An x-ray and computed tomography (CT) scan of the chest revealed bilateral diffuse ground glass opacities. A CT scan of the brain showed a subarachnoid hemorrhage (SAH). Electrocardiography (ECG) showed normal sinus rhythm, but troponin I was elevated. Echocardiography revealed left ventricular apical hypokinesia. The coronary angiogram was normal. A diagnosis of TCM with SAH was made. Appropriate emergent care was provided, and at follow-up, she made a complete cardiologic recovery. TCM is a puzzling condition in an emergency setting and accurate and timely diagnosis is imperative in the management. Early prevention of hypoxemia and maintenance of mean arterial pressure and cerebral perfusion pressure is critical in determining the long-term outcome of the patient in the setting of co-existing CNS pathologies.

The Heart Is at Risk: Understanding Stroke-Heart-Brain Interactions with Focus on Neurogenic Stress Cardiomyopathy-A Review

In recent years, it has been convincingly demonstrated that acute brain injury may cause severe cardiac complications-such as neurogenic stress cardiomyopathy (NSC), a specific form of takotsubo cardiomyopathy. The pathophysiology of these brain-heart interactions is complex and involves sympathetic hyperactivity, activation of the hypothalamic-pituitary-adrenal axis, as well as immune and inflammatory pathways. There have been great strides in our understanding of the axis from the brain to the heart in patients with isolated acute brain injury and more specifically in patients with stroke. On the other hand, in patients with NSC, research has mainly focused on hemodynamic dysfunction due to arrhythmias, regional wall motion abnormality, or left ventricular hypokinesia that leads to impaired cerebral perfusion pressure. Comparatively little is known about the underlying secondary and delayed cerebral complications. The aim of the present review is to describe the stroke-heart-brain axis and highlight the main pathophysiological mechanisms leading to secondary and delayed cerebral injury in patients with concurrent hemorrhagic or ischemic stroke and NSC as well as to identify further areas of research that could potentially improve outcomes in this specific patient population.

Acute Myocardial Infarction and Concomitant Acute Intracranial Hemorrhage: Clinical Characteristics and Outcomes

This study aimed to evaluate the demographic and clinical characteristics, treatments and outcomes of concomitant acute myocardial infarction (AMI) and acute intracranial hemorrhage (ICH). All patients diagnosed with concomitant AMI and acute ICH admitted to our institution were included retrospectively. The patient demographics, clinical characteristics, neuroimaging and treatment approaches were analyzed, and the outcomes of interest included disability as defined by the modified Rankin Scale (mRS) score and all-cause mortality within 1 year of follow-up. Of a total of 4972 patients with AMI, 8 patients (0.2%) with concomitant acute ICH were recruited for the study, including ST-segment elevation myocardial infarction (STEMI, 5 cases) and non-STEMI (3 cases). New-onset acute ICH in 4 of the 5 patients (80%) occurred within 24 hours after the AMI event, and all these patients had a sudden decrease in the level of consciousness, with an average decrease of 4.6 on the Glasgow Coma Scale. All 5 out of 8 patients had irregular shapes and uncommon sites of hematoma presentation documented on CT scans. Unfortunately, 2 patients died from a progression of ICH within 1 week, and 2 of the 6 survivors had poor functional outcomes (mRS ≥3) at the 1-year follow-up. Concomitant acute ICH and AMI are rare complications displaying unique iconography. Acute ICH caused serious prejudice in AMI with higher mortality and poor functional outcomes, and cardiac catheterization without the administration of antithrombotic or antiplatelet agents was feasible for patients who had unstable hemodynamics or STEMI.

Subarachnoidal hemorrhage related cardiomyopathy: an overview of Tako-Tsubo cardiomyopathy and related cardiac syndromes

INTRODUCTION

Subarachnoid hemorrhage (SAH) is caused by a ruptured intracranial aneurysm leading to acute extravasation of blood into the subarachnoid space. SAH has an incidence of 6.3 per 100,000 persons per year in Europe and accounts for 5% of all strokes. SAH occurs at a relatively young age and has poor clinical outcomes and high mortality rates. Cardiac syndromes are regularly seen in patients with acute neurologic disease including SAH. These cardiac complications of SAH are associated with increased morbidity and mortality and present in a large variety and severity.

AREAS COVERED

The main goal of this review is to describe the SAH-related cardiac syndromes. Secondly, we will provide an overview of the underlying pathophysiology regarding the development of cardiac syndromes. Thirdly, we will describe the impact of cardiac syndromes on patient outcome.

EXPERT OPINION

Of all neurology patients, SAH patients have the highest risk of developing takotsubo syndrome (TTS), occurring in about 0.8-30% of patients. Both TTS and neurogenic stunned myocardium have many similarities on echocardiographic evaluation. In European Cardiology consensus, SAH is recognized as a primary cause of TTS.

Assessing the Global Impact on the Mouse Kidney After Traumatic Brain Injury: A Transcriptomic Study

Purpose

In this study, we use animal models combined with bioinformatics strategies to investigate the potential changes in overall renal transcriptional expression after traumatic brain injury.

Methods

Microarray analysis was performed after kidney acquisition using unilateral controlled cortical impact as the primary mouse TBI model. Multi-oriented gene set enrichment analysis was performed for differentially expressed genes.

Results

The results showed that TBI affected the gene set associated with mitochondria function in kidney cells, and a negative enrichment of gene sets associated with immune cell migration and epidermal development was also observed. Analysis of the disease phenotype gene set revealed that differential expression of mitochondria-related genes was associated with lactate metabolism. Alternatively, activation and adhesion of immune cells associated with the complement system may promote autoinflammation in kidney tissue. The simulated immune cell infiltration analysis showed an increase in the proportion of activated memory CD4 T cells and a decrease in the proportion of resting memory CD4 T cells, suggesting that activated memory CD4 T cell infiltration may be involved in the inflammation of renal tissue and cause damage to renal cells, such as principal cells, mesangial cells and loops of Henle cells.

Conclusion

This study is the first to reveal the effects of brain trauma on the kidney. TBI may affect the expression of mitochondria function-related gene sets in renal cells by increasing lactate. It may also affect renal mesangial cells by inducing increased infiltration of immune cells through mechanisms related to complement system activation or autoimmune antibodies.

Assessment of cardiac function in rat endovascular perforation model of subarachnoid hemorrhage; A model of subarachnoid hemorrhage-induced cardiac dysfunction

Although the association between cardiac dysfunction and subarachnoid hemorrhage (SAH) has been recognized, its precise underlying mechanism remains unknown. Furthermore, no suitable animal models are available to study this association. Here, we established an appropriate animal model of SAH-induced cardiac dysfunction and elucidated its mechanism. In this rat model, contrast-enhanced computed tomography of the brain confirmed successful induction of SAH. Electrocardiography detected abnormalities in 55% of the experimental animals, while echocardiography indicated cardiac dysfunction in 30% of them. Further evaluation of left ventriculography confirmed cardiac dysfunction, which was transient and recovered over time. Additionally, in this SAH model, the expression of the acute phase reaction protein, proto-oncogene c-Fos increased in the paraventricular hypothalamic nucleus (PVN), the sympathetic nerve center of the brain. Polymerase chain reaction analysis revealed that the SAH model with cardiac dysfunction had higher levels of the macrophage-associated chemokine (C-X-C motif) ligand 1 (CXCL-1) and chemokine (C-C motif) ligand 2 (CCL-2) than the SAH model without cardiac dysfunction. Our results suggested that SAH caused inflammation and macrophage activation in the PVN, leading to sympathetic hyperexcitability that might cause cardiac dysfunction directly and indirectly. This animal model may represent a powerful tool to investigate the mechanisms of the brain-heart pathway.

Interactions between the Autonomic Nervous System and the Immune System after Stroke

Acute stroke is one of the leading causes of morbidity and mortality worldwide. Stroke-induced immune-inflammatory response occurs in the perilesion areas and the periphery. Although stroke-induced immunosuppression may alleviate brain injury, it hinders brain repair as the immune-inflammatory response plays a bidirectional role after acute stroke. Furthermore, suppression of the systemic immune-inflammatory response increases the risk of life-threatening systemic bacterial infections after acute stroke. Therefore, it is essential to explore the mechanisms that underlie the stroke-induced immune-inflammatory response. Autonomic nervous system (ANS) activation is critical for regulating the local and systemic immune-inflammatory responses and may influence the prognosis of acute stroke. We review the changes in the sympathetic and parasympathetic nervous systems and their influence on the immune-inflammatory response after stroke. Importantly, this article summarizes the mechanisms on how ANS regulates the immune-inflammatory response through neurotransmitters and their receptors in immunocytes and immune organs after stroke. To facilitate translational research, we also discuss the promising therapeutic approaches modulating the activation of the ANS or the immune-inflammatory response to promote neurologic recovery after stroke. © 2022 American Physiological Society. Compr Physiol 12:3665-3704, 2022.

Melatonin and the Brain–Heart Crosstalk in Neurocritically Ill Patients—From Molecular Action to Clinical Practice

Brain injury, especially traumatic brain injury (TBI), may induce severe dysfunction of extracerebral organs. Cardiac dysfunction associated with TBI is common and well known as the brain–heart crosstalk, which broadly refers to different cardiac disorders such as cardiac arrhythmias, ischemia, hemodynamic insufficiency, and sudden cardiac death, which corresponds to acute disorders of brain function. TBI-related cardiac dysfunction can both worsen the brain damage and increase the risk of death. TBI-related cardiac disorders have been mainly treated symptomatically. However, the analysis of pathomechanisms of TBI-related cardiac dysfunction has highlighted an important role of melatonin in the prevention and treatment of such disorders. Melatonin is a neurohormone released by the pineal gland. It plays a crucial role in the coordination of the circadian rhythm. Additionally, melatonin possesses strong anti-inflammatory, antioxidative, and antiapoptotic properties and can modulate sympathetic and parasympathetic activities. Melatonin has a protective effect not only on the brain, by attenuating its injury, but on extracranial organs, including the heart. The aim of this study was to analyze the molecular activity of melatonin in terms of TBI-related cardiac disorders. Our article describes the benefits resulting from using melatonin as an adjuvant in protection and treatment of brain injury-induced cardiac dysfunction.

The association of Takotsubo cardiomyopathy and aneurysmal subarachnoid hemorrhage: A U.S. nationwide analysis

OBJECTIVE

Takotsubo cardiomyopathy (TC) is a stress-induced cardiomyopathy that can be precipitated by aneurysmal subarachnoid hemorrhage (aSAH). Several studies have shown patients who develop TC following aSAH have an increased risk of disability and mortality. The goal of this study is to examine the incidence of TC in aSAH, identify its risk factors, and analyze its impact on patient outcomes.

METHODS

Data for patients with aSAH between the years of 2009 and 2018 were extracted from the Nationwide Inpatient Sample (NIS) and stratified based on the diagnosis of TC. Univariate analysis was used to assess the incidence of TC and covariates including patient demographics, aneurysmal treatment, in-hospital mortality rate, length of stay and costs. Multivariate logistic regression models analyzed the relationship between TC and these variables RESULTS: 80,915 aSAH patient-discharges were included in this study, 673 (0.83%) of which, developed TC. Females (OR 3.49, CI [2.82-4.33], P < 0.001), white ethnicity (69% vs 63%, P = 0.003) and patients with certain comorbidities including smoking (OR 1.64, CI [1.38-1.95], P < 0.0001) and seizures (OR 1.32, CI [1.07, 1.64], P = 0.01) were most likely to develop TC. Patients who developed TC had significantly increased mortality (OR 1.36, CI [1.13-1.65], P = 0.001), hospital stays (mean days of 19.4 vs 11.5, P < 0.0001), and costs ($104,111 vs $48,734, P < 0.0001). Hypertension (OR 0.63, CI [0.54-0.74], P < 0.0001) and hyperlipidemia (OR 0.63, CI [0.51-0.77], P < 0.0001) were found to be protective against TC. Patients with TC after acute SAH were more likely to undergo endovascular coiling (OR 1.68, CI [1.327-2.127], P < 0.001) rather than surgical clipping (OR 0.66, CI [0.52-0.83], P < 0.0001).

CONCLUSIONS

Female sex, white ethnicity, smoking and seizures represented significant predictors of developing TC after aSAH, while hypercholesterolemia and hypertension were protective.

Role of autonomic system imbalance in neurogenic pulmonary oedema

Neurogenic pulmonary oedema (NPE) is a life-threatening complication that develops rapidly and dramatically after an injury to the central nervous system (CNS). The autonomic system imbalance produced by severe brain damage may play an important role in the development of NPE. Activation of the sympathetic nervous system and inhibition of the vagus nerve system are essential prerequisites for autonomic system imbalance. The more severe the damage, the more pronounced the phenomenon. Sympathetic hyperactivity is associated with increased release of catecholamines from peripheral sympathetic nerve endings, which can cause dramatic changes in haemodynamics and cause pulmonary oedema. On the other hand, the abnormal inflammatory response caused by vagus nerve inhibition may also play an important role in the pathogenesis of NPE. The perspective of autonomic system imbalance seems to perfectly integrate the existing pathogenesis of NPE and can explain the entire development progression of NPE.

Central sympathetic nerve activation in subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a life-threatening condition, and although its two main complications-cerebral vasospasm (CVS)/delayed cerebral ischemia (DCI) and early brain injury (EBI)-have been widely studied, prognosis has not improved over time. The sympathetic nerve (SN) system is important for the regulation of cardiovascular function and is closely associated with cerebral vessels and the regulation of cerebral blood flow and cerebrovascular function; thus, excessive SN activation leads to a rapid breakdown of homeostasis in the brain. In the hyperacute phase, patients with SAH can experience possibly lethal conditions that are thought to be associated with SN activation (catecholamine surge)-related arrhythmia, neurogenic pulmonary edema, and irreversible injury to the hypothalamus and brainstem. Although the role of the SN system in SAH has long been investigated and considerable evidence has been collected, the exact pathophysiology remains undetermined, mainly because the relationships between the SN system and SAH are complicated, and many SN-modulating factors are involved. Thus, research concerning these relationships needs to explore novel findings that correlate with the relevant concepts based on past reliable evidence. Here, we explore the role of the central SN (CSN) system in SAH pathophysiology and provide a comprehensive review of the functional CSN network; brain injury in hyperacute phase involving the CSN system; pathophysiological overlap between the CSN system and the two major SAH complications, CVS/DCI and EBI; CSN-modulating factors; and SAH-related extracerebral organ injury. Further studies are warranted to determine the specific roles of the CSN system in the brain injuries associated with SAH.

Post-Stroke Cardiovascular Complications and Neurogenic Cardiac Injury: JACC State-of-the-Art Review

Over 1.5 million deaths worldwide are caused by neurocardiogenic syndromes. Furthermore, the consequences of deleterious brain-heart interactions are not limited to fatal complications. Cardiac arrhythmias, heart failure, and nonfatal coronary syndromes are also common. The brain-heart axis is implicated in post-stroke cardiovascular complications known as the stroke-heart syndrome, sudden cardiac death, and Takotsubo syndrome, among other neurocardiogenic syndromes. Multiple pathophysiological mechanisms with the potential to be targeted with novel therapies have been identified in the last decade. In the present state-of-the-art review, we describe recent advances in the understanding of anatomical and functional aspects of the brain-heart axis, cardiovascular complications after stroke, and a comprehensive pathophysiological model of stroke-induced cardiac injury.

Correlation of cardiac function and cerebral perfusion in a murine model of subarachnoid hemorrhage

Cerebral hypoperfusion is a key factor for determining the outcome after subarachnoid hemorrhage (SAH). A subset of SAH patients develop neurogenic stress cardiomyopathy (NSC), but it is unclear to what extent cerebral hypoperfusion is influenced by cardiac dysfunction after SAH. The aims of this study were to examine the association between cardiac function and cerebral perfusion in a murine model of SAH and to identify electrocardiographic and echocardiographic signs indicative of NSC. We quantified cortical perfusion by laser SPECKLE contrast imaging, and myocardial function by serial high-frequency ultrasound imaging, for up to 7 days after experimental SAH induction in mice by endovascular filament perforation. Cortical perfusion decreased significantly whereas cardiac output and left ventricular ejection fraction increased significantly shortly post-SAH. Transient pathological ECG and echocardiographic abnormalities, indicating NSC (right bundle branch block, reduced left ventricular contractility), were observed up to 3 h post-SAH in a subset of model animals. Cerebral perfusion improved over time after SAH and correlated significantly with left ventricular end-diastolic volume at 3, 24, and 72 h. The murine SAH model is appropriate to experimentally investigate NSC. We conclude that in addition to cerebrovascular dysfunction, cardiac dysfunction may significantly influence cerebral perfusion, with LVEDV presenting a potential parameter for risk stratification.

Neuroinflammatory Mechanisms in Ischemic Stroke: Focus on Cardioembolic Stroke, Background, and Therapeutic Approaches

One of the most important causes of neurological morbidity and mortality in the world is ischemic stroke. It can be a result of multiple events such as embolism with a cardiac origin, occlusion of small vessels in the brain, and atherosclerosis affecting the cerebral circulation. Increasing evidence shows the intricate function played by the immune system in the pathophysiological variations that take place after cerebral ischemic injury. Following the ischemic cerebral harm, we can observe consequent neuroinflammation that causes additional damage provoking the death of the cells; on the other hand, it also plays a beneficial role in stimulating remedial action. Immune mediators are the origin of signals with a proinflammatory position that can boost the cells in the brain and promote the penetration of numerous inflammatory cytotypes (various subtypes of T cells, monocytes/macrophages, neutrophils, and different inflammatory cells) within the area affected by ischemia; this process is responsible for further ischemic damage of the brain. This inflammatory process seems to involve both the cerebral tissue and the whole organism in cardioembolic stroke, the stroke subtype that is associated with more severe brain damage and a consequent worse outcome (more disability, higher mortality). In this review, the authors want to present an overview of the present learning of the mechanisms of inflammation that takes place in the cerebral tissue and the role of the immune system involved in ischemic stroke, focusing on cardioembolic stroke and its potential treatment strategies.

Plasma brain natriuretic peptide level on admission predicts long-term outcome in patients with non-traumatic subarachnoid hemorrhage

INTRODUCTION

Non-traumatic subarachnoid hemorrhage (SAH) is a type of stroke that still has a high mortality rate. Some patients with SAH have electrocardiography (ECG) abnormalities or asymptomatic left ventricular apical ballooning, and requires intervention by cardiologists. However, the impact of cardiac abnormalities after SAH onset remains unclear. We investigated whether ECG abnormalities, myocardial damage, sympathetic nervous activity or echocardiographic left ventricular wall motion abnormalities (WMA) could provide additional risk stratification in patients with SAH.

METHODS

We studied 118 SAH patients (78 women, age 63 ± 15) without a history of heart disease. Neurological grade (Hunt and Kosnik Grade) and clinical factors were evaluated. A standard 12-lead ECG, echocardiography and blood samples were obtained within 48 h after SAH onset. ECG abnormalities were defined as abnormal Q wave, ST elevation, giant T-wave inversion or QT prolongation.

RESULTS

Twenty of 118 patients (17%) died during the follow-up (35 ± 31 months). Death was significantly associated with higher age (p < 0.0001), neurological grade (p < 0.0001), elevated BNP level (p < 0.0001), increased plasma norepinephrine levels (p < 0.0001) and WMA (p = 0.0070), while ECG abnormalities were not significantly associated. Neurological grade (p < 0.0001), age (p = 0.0047) and BNP (p = 0.0014, hazard ratio 1.0255 for each 1 pg/mL increase in BNP, 95%CI 1.0088 to 1.0499) were independently associated with death. Patients with BNP ≥ 96.6 had a higher risk of death (log- rank p < 0.0001).

CONCLUSION

Plasma BNP might provide an additional risk stratification in patients with non-traumatic SAH that requires intervention by cardiologists for both its prevention management after onset.

Reverse takotsubo cardiomyopathy in fulminant COVID-19 associated with cytokine release syndrome and resolution following therapeutic plasma exchange: a case-report

Background

Fulminant (life-threatening) COVID-19 can be associated with acute respiratory failure (ARF), multi-system organ failure and cytokine release syndrome (CRS). We present a rare case of fulminant COVID-19 associated with reverse-takotsubo-cardiomyopathy (RTCC) that improved with therapeutic plasma exchange (TPE).

Case presentation

A 40 year old previous healthy male presented in the emergency room with 4 days of dry cough, chest pain, myalgias and fatigue. He progressed to ARF requiring high-flow-nasal-cannula (flow: 60 L/minute, fraction of inspired oxygen: 40%). Real-Time-Polymerase-Chain-Reaction (RT-PCR) assay confirmed COVID-19 and chest X-ray showed interstitial infiltrates. Biochemistry suggested CRS: increased C-reactive protein, lactate dehydrogenase, ferritin and interleukin-6. Renal function was normal but lactate levels were elevated. Electrocardiogram demonstrated non-specific changes and troponin-I levels were slightly elevated. Echocardiography revealed left ventricular (LV) basal and midventricular akinesia with apex sparing (LV ejection fraction: 30%) and depressed cardiac output (2.8 L/min) consistent with a rare variant of stress-related cardiomyopathy: RTCC. His ratio of partial arterial pressure of oxygen to fractional inspired concentration of oxygen was < 120. He was admitted to the intensive care unit (ICU) for mechanical ventilation and vasopressors, plus antivirals (lopinavir/ritonavir), and prophylactic anticoagulation. Infusion of milrinone failed to improve his cardiogenic shock (day-1). Thus, rescue TPE was performed using the Spectra Optia™ Apheresis System equipped with the Depuro D2000 Adsorption Cartridge (Terumo BCT Inc., USA) without protective antibodies. Over 5 days he received daily TPE (each lasting 4 hours). His lactate levels, oxygenation, and LV function normalized and he was weaned off vasopressors. His inflammation markers improved, and he was extubated on day-7. RT-PCR was negative on day-17. He was discharged to home isolation in good condition.

Conclusion

Stress-cardiomyopathy may complicate the course of fulminant COVID-19 with associated CRS. If inotropic therapy fails, TPE without protective antibodies may help rescue the critically ill patient.

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

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

Crosstalk between brain, lung and heart in critical care

Extracerebral complications, especially pulmonary and cardiovascular, are frequent in brain-injured patients and are major outcome determinants. Two major pathways have been described: brain-lung and brain-heart interactions. Lung injuries after acute brain damages include ventilator-associated pneumonia (VAP), acute respiratory distress syndrome (ARDS) and neurogenic pulmonary œdema (NPE), whereas heart injuries can range from cardiac enzymes release, ECG abnormalities to left ventricle dysfunction or cardiogenic shock. The pathophysiologies of these brain-lung and brain-heart crosstalk are complex and sometimes interconnected. This review aims to describe the epidemiology and pathophysiology of lung and heart injuries in brain-injured patients with the different pathways implicated and the clinical implications for critical care physicians.

[Troponin elevation in acute ischemic stroke-unspecific or acute myocardial infarction? : Diagnostics and clinical implications]

Routine determination of troponin levels is recommended for all patients with acute ischemic stroke. In 20-55% of these patients the troponin levels are elevated, which may be caused by ischemic as well as non-ischemic myocardial damage and particularly neurocardiogenic myocardial damage. In patients with acute ischemic stroke, the prevalence of previously unknown coronary heart disease is reported to be up to 27% and is prognostically relevant for these patients; however, relevant coronary stenoses are less frequently detected in stroke patients with troponin elevation compared to patients with non-ST elevation myocardial infarction. The risk of secondary intracerebral hemorrhage due to the necessity for dual platelet aggregation inhibition illustrates the challenging indication for invasive coronary diagnostics and revascularization. Therefore, a diagnostic work-up and interdisciplinary risk evaluation appropriate to the urgency are necessary in order to be able to determine a reasonable treatment approach with timing of the intervention, type and duration of blood thinning. In addition to conventional examination methods, multimodal cardiac imaging is increasingly used for this purpose. This review article aims to provide a pragmatic and clinically oriented approach to diagnostic and therapeutic procedures, taking into account the available evidence.

Aerobic Training and Mobilization Early Post-stroke: Cautions and Considerations

Knowledge gaps exist in how we implement aerobic exercise programs during the early phases post-stroke. Therefore, the objective of this review was to provide evidence-based guidelines for pre-participation screening, mobilization, and aerobic exercise training in the hyper-acute and acute phases post-stroke. In reviewing the literature to determine safe timelines of when to initiate exercise and mobilization we considered the following factors: arterial blood pressure dysregulation, cardiac complications, blood-brain barrier disruption, hemorrhagic stroke transformation, and ischemic penumbra viability. These stroke-related impairments could intensify with inappropriate mobilization/aerobic exercise, hence we deemed the integrity of cerebral autoregulation to be an essential physiological consideration to protect the brain when progressing exercise intensity. Pre-participation screening criteria are proposed and countermeasures to protect the brain from potentially adverse circulatory effects before, during, and following mobilization/exercise sessions are introduced. For example, prolonged periods of standing and static postures before and after mobilization/aerobic exercise may elicit blood pooling and/or trigger coagulation cascades and/or cerebral hypoperfusion. Countermeasures such as avoiding prolonged standing or incorporating periodic lower limb movement to activate the venous muscle pump could counteract blood pooling after an exercise session, minimize activation of the coagulation cascade, and mitigate potential cerebral hypoperfusion. We discuss patient safety in light of the complex nature of stroke presentations (i.e., type, severity, and etiology), medical history, comorbidities such as diabetes, cardiac manifestations, medications, and complications such as anemia and dehydration. The guidelines are easily incorporated into the care model, are low-risk, and use minimal resources. These and other strategies represent opportunities for improving the safety of the activity regimen offered to those in the early phases post-stroke. The timeline for initiating and progressing exercise/mobilization parameters are contingent on recovery stages both from neurobiological and cardiovascular perspectives, which to this point have not been specifically considered in practice. This review includes tailored exercise and mobilization prescription strategies and precautions that are not resource intensive and prioritize safety in stroke recovery.

Autonomic dysfunction following traumatic brain injury: translational insights

Although there is a substantial amount of research on the neurological consequences of traumatic brain injury (TBI), there is a knowledge gap regarding the relationship between TBI and the pathophysiology of organ system dysfunction and autonomic dysregulation. In particular, the mechanisms or incidences of renal or cardiac complications after TBI are mostly unknown. Autonomic dysfunction following TBI exacerbates secondary injury and may contribute to nonneurologial complications that prolong hospital length of stay. Gaining insights into the mechanisms of autonomic dysfunction can guide advancements in monitoring and treatment paradigms to improve acute survival and long-term prognosis of TBI patients. In this paper, the authors will review the literature on autonomic dysfunction after TBI and possible mechanisms of paroxysmal sympathetic hyperactivity. Specifically, they will discuss the link among the brain, heart, and kidneys and review data to direct future research on and interventions for TBI-induced autonomic dysfunction.

Impact of Acute Cardiac Complications After Subarachnoid Hemorrhage on Long-Term Mortality and Cardiovascular Events

Background

Cardiac complications frequently occur after subarachnoid hemorrhage (SAH) and are associated with an increased risk of neurological complications and poor outcomes. The aim of this study was to evaluate the impact of acute cardiac complications after SAH on long-term mortality and cardiovascular events.

Methods

All patients admitted to our Neuro intensive care unit with verified SAH from January 2010 to April 2015, and electrocardiogram, echocardiogram, and troponin T or NTproBNP data obtained within 72 h of admission were included in the study. Mortality data were obtained from the Swedish population register. Data regarding cause of death and hospitalization for cardiovascular events were obtained from the Swedish Board of Health and Welfare.

Results

A total of 455 patients were included in the study analysis. There were 102 deaths during the study period. Cardiac troponin release (HR 1.08, CI 1.02–1.15 per 100 ng/l, p = 0.019), NTproBNP (HR 1.05, CI 1.01–1.09 per 1000 ng/l, p = 0.018), and ST-T abnormalities (HR 1.53, CI 1.02–2.29, p = 0.040) were independently associated with an increased risk of death. However, these associations were significant only during the first 3 months after the hemorrhage. Cardiac events were observed in 25 patients, and cerebrovascular events were observed in 62 patients during the study period. ST-T abnormalities were independently associated with an increased risk of cardiac events (HR 5.52, CI 2.07–14.7, p < 0.001), and stress cardiomyopathy was independently associated with an increased risk of cerebrovascular events (HR 3.65, CI 1.55–8.58, p = 0.003).

Conclusion

Cardiac complications after SAH are associated with an increased risk of short-term death. Patients with electrocardiogram abnormalities and stress cardiomyopathy need appropriate follow-up for the identification of cardiac disease or risk factors for cardiovascular disease.

Electronic supplementary material

The online version of this article (10.1007/s12028-018-0558-0) contains supplementary material, which is available to authorized users.

Loss of consciousness at onset of aneurysmal subarachnoid hemorrhage in good-grade patients

Loss of consciousness (LOC) at presentation with aneurysmal subarachnoid hemorrhage (aSAH) has been associated with early brain injury and poor functional outcome. The impact of LOC on the clinical course after aSAH deserves further exploration. A retrospective analysis of 149 aSAH patients who were prospectively enrolled in the Cerebral Aneurysm Renin Angiotensin Study (CARAS) between 2012 and 2015 was performed. The impact of LOC was analyzed with emphasis on patients presenting in excellent or good neurological condition (Hunt and Hess 1 and 2). A total of 50/149 aSAH patients (33.6%) experienced LOC at presentation. Loss of consciousness was associated with severity of neurological condition upon admission (Hunt and Hess, World Federation of Neurosurgical Societies (WFNS), Glasgow Coma Scale (GCS) grade), hemorrhage burden on initial head CT (Fisher CT grade), acute hydrocephalus, cardiac instability, and nosocomial infection. Of Hunt and Hess grade 1 and 2 patients, 21/84 (25.0%) suffered LOC at presentation. Cardiac instability and nosocomial infection were significantly more frequent in these patients. In multivariable analysis, LOC was the predominant predictor of cardiac instability and nosocomial infection. Loss of consciousness at presentation with aSAH is associated with an increased rate of complications, even in good-grade patients. The presence of LOC may identify good-grade patients at risk for complications such as cardiac instability and nosocomial infection.

Assessment of the ECG T-Wave in Patients With Subarachnoid Hemorrhage

BACKGROUND

Prolongation of the interval from the peak to the end of the T wave (Tp-Te) on a 12-lead electrocardiogram (ECG) is associated with ventricular arrhythmias. The aim of this study was to clarify associations between Tp-Te, Tp-Te/QT, and Tp-Te/rate-corrected QT (QTc) with clinical severity of subarachnoid hemorrhage (SAH) and clinical outcomes.

METHODS

This retrospective study included 222 patients with acute SAH (group S) and 306 patients with unruptured cerebral aneurysms (group U). Tp-Te, Tp-Te/QT, and Tp-Te/QTc were manually measured in standard 12-lead ECG recordings on admission and comparisons made between patients in groups S and U. The relationships of these ECG parameters with Hunt and Hess grade and Glasgow outcome scale were analyzed using multiple logistic regression analysis after adjustment for confounding factors.

RESULTS

Tp-Te, Tp-Te/QT, and Tp-Te/QTc were significantly greater in group S than in group U (group S: 109±30, 0.26±0.07, and 0.24±0.06 ms; group U: 84±12, 0.22±0.03, and 0.21±0.03 ms, respectively; P < 0.0001). In addition, in the multiple logistic regression analyses these variables were positively correlated with the Hunt and Hess grade (Tp-Te odds ratio [95% confidence interval], 2.414 [1.375-4.238], P=0.002; Tp-Te/QT, 1.886 [1.085-3.277], P = 0.024; Tp-Te/QTc, 1.873 [1.07-3.278], P=0.028, and negatively correlated with Glasgow outcome scale Tp-Te odds ratio [95% confidence interval], 4.168 [2.409-7.209], P<0.001; Tp-Te/QT, 2.434 [1.413-4.192], P=0.001; Tp-Te/QTc 2.953 [1.703-5.123], P<0.001).

CONCLUSIONS

Tp-Te, Tp-Te/QT, and Tp-Te/QTc are associated with disease severity and clinical outcome in patients with SAH.

Troponin I as an Early Biomarker of Cardiopulmonary Parameters Within the First 24 Hours After Nontraumatic Subarachnoid Hemorrhage in Intensive Care Unit Patients

OBJECTIVE

The elevation of serum cardiac troponin I (TNI) in patients with nontraumatic subarachnoid hemorrhage (ntSAH) is a well-known phenomenon. However, the relation between elevated TNI and different cardiopulmonary parameters (CPs) within the first 24 hours after ntSAH is unknown. The present study was conducted to investigate the association between TNI and different CP in patients with ntSAH within the first 24 hours of intensive care unit (ICU) treatment.

PATIENTS AND METHODS

We retrospectively analyzed a consecutive group of 117 patients with ntSAH admitted to our emergency department between January 2008 and February 2017. Blood samples were taken to determine TNI values on admission. Demographic data, baseline Glasgow Coma Scale (GCS) score, World Federation of Neurosurgical Societies (WFNS) score, baseline Fisher grade (FG), norepinephrine application rate (NAR) in µg/kg/min, and inspiratory oxygen fraction (OF) were recorded within the first 24 hours.

RESULTS

An increased TNI value was found in 32 (27.4%) of 117 patients. There was a significant correlation between initial elevated TNI and a low WFNS score (P = .007), a low GCS score (P = .003) as well as a high OF (P = <.001). The FG (P = .27) and NAR (P = .08) within the first 24 hours of ICU treatment did not show any significant correlation.

CONCLUSIONS

In the present study, an increased TNI value was significantly associated with a low WFNS score and GCS score on admission. The TNI was a predictor of the need for a higher OF within the first 24 hours after ntSAH so that TNI could be an informative biomarker to improve ICU therapy.

Acute Cardiac Complications in Critical Brain Disease

Acute cardiac complications in critical brain disease should be understood as a clinical condition representing an intense brain-heart crosstalk and might mimic ischemic heart disease. Two main entities (neurogenic stunned myocardium [NSM] and stress cardiomyopathy) have been better characterized in the neurocritically ill patients and they portend worse clinical outcomes in these cases. The pathophysiology of NSM remains elusive. However, significant progress has been made on the early identification of neurocardiac compromise following acute critical brain disease. Effective prevention and treatment interventions are yet to be determined.

Acute Cardiac Complications in Critical Brain Disease

Acute cardiac complications in critical brain disease should be understood as a clinical condition representing an intense brain-heart crosstalk and might mimic ischemic heart disease. Two main entities (neurogenic stunned myocardium [NSM] and stress cardiomyopathy) have been better characterized in the neurocritically ill patients and they portend worse clinical outcomes in these cases. The pathophysiology of NSM remains elusive. However, significant progress has been made on the early identification of neurocardiac compromise following acute critical brain disease. Effective prevention and treatment interventions are yet to be determined.

Brain-Heart Interactions in Traumatic Brain Injury

The cardiovascular manifestations associated with nontraumatic head disorders are commonly known. Similar manifestations have been reported in patients with traumatic brain injury (TBI); however, the underlying mechanisms and impact on the patient's clinical outcomes are not well explored. The neurocardiac axis theory and neurogenic stunned myocardium phenomenon could partly explain the brain-heart link and interactions and can thus pave the way to a better understanding and management of TBI. Several observational retrospective studies have shown a promising role for beta-adrenergic blockers in patients with TBI in reducing the overall TBI-related mortality. However, several questions remain to be answered in clinical randomized-controlled trials, including population selection, beta blocker type, dosage, timing, and duration of therapy, while maintaining the optimal mean arterial pressure and cerebral perfusion pressure in patients with TBI.

Practical Application of Biogenic Amine Profiles for the Diagnosis of Patients with Ischemic Stroke

BACKGROUND

Ischemic stroke (IS) is still one of the major issues in medicine. Still, early diagnosis and misdiagnosis remain the main barriers for proper patient treatment and follow-up. Exploring new potential diagnostic biomarkers for IS is relevant to decrease patient morbidity and the occurrence of poststroke diseases. Biomedical analysis could bring new light to the background of IS and-in such a way-propose new bioanalytical tools for the early diagnosis, prognostication, and monitoring of IS.

MATERIALS AND METHODS

This research aimed to present a discussion on the employment of biogenic amines (BAs), as well as their precursory amino acids and main metabolites, as a new panel of biomarkers for IS. Preliminary patient data were presented and the patients were described with respect to their clinical history and examination records, as well as scientific data gained from the liquid extraction-capillary electrophoresis determination of BAs in the patients' urine samples.

RESULTS

The results showed the potential of BA screening using the developed sample preparation and analysis methods in urine during IS, and this will be further studied on a more numerous group of patients with IS to reveal the usefulness of BAs as a new panel of biomarkers for early IS diagnosis and prognostication.

CONCLUSIONS

To our best knowledge, this methodology for the first time has been used for the simultaneous analysis of multiple small molecular biomarkers. In addition, the factors that might influence the determination of BAs in real samples were pointed out.

Cardiac troponins: from myocardial infarction to chronic disease

Elucidation of the physiologically distinct subunits of troponin in 1973 greatly facilitated our understanding of cardiac contraction. Although troponins are expressed in both skeletal and cardiac muscle, there are isoforms of troponin I/T expressed selectively in the heart. By exploiting cardiac-restricted epitopes within these proteins, one of the most successful diagnostic tests to date has been developed: cardiac troponin (cTn) assays. For the past decade, cTn has been regarded as the gold-standard marker for acute myocardial necrosis: the pathological hallmark of acute myocardial infarction (AMI). Whilst cTn is the cornerstone for ruling-out AMI in patients presenting with a suspected acute coronary syndrome (ACS), elevated cTn is frequently observed in those without clinical signs indicative of AMI, often reflecting myocardial injury of 'unknown origin'. cTn is commonly elevated in acute non-ACS conditions, as well as in chronic diseases. It is unclear why these elevations occur; yet they cannot be ignored as cTn levels in chronically unwell patients are directly correlated to prognosis. Paradoxically, improvements in assay sensitivity have meant more differential diagnoses have to be considered due to decreased specificity, since cTn is now more easily detected in these non-ACS conditions. It is important to be aware cTn is highly specific for myocardial injury, which could be attributable to a myriad of underlying causes, emphasizing the notion that cTn is an organ-specific, not disease-specific biomarker. Furthermore, the ability to detect increased cTn using high-sensitivity assays following extreme exercise is disconcerting. It has been suggested troponin release can occur without cardiomyocyte necrosis, contradicting conventional dogma, emphasizing a need to understand the mechanisms of such release. This review discusses basic troponin biology, the physiology behind its detection in serum, its use in the diagnosis of AMI, and some key concepts and experimental evidence as to why cTn can be elevated in chronic diseases.

The role of endothelial nitric oxide synthase -786 T/C polymorphism in cardiac instability following aneurysmal subarachnoid hemorrhage

INTRODUCTION

Cardiac abnormalities are observed frequently after aneurysmal subarachnoid hemorrhage (aSAH). A subset of aSAH patients develops neurogenic cardiomyopathy, likely induced by catecholamine excess. Genetic polymorphisms of the endothelial nitric oxide synthase (eNOS) gene have been linked to decreased nitric oxide (NO) levels, coronary artery spasm, and myocardial infarction. The role of the eNOS single nucleotide polymorphism (SNP) -786 T/C in cardiac instability following aSAH has not been previously investigated.

METHODS

From 2012 to 2015, aSAH patients were prospectively enrolled in the Cerebral Aneurysm Renin Angiotensin System (CARAS) study at two academic institutions. Blood samples were used to assess the eNOS SNP -786 T/C rs2070744 through 5'exonuclease (Taqman) genotyping assays. Associations between this polymorphism and cardiac instability following aSAH were analyzed.

RESULTS

Multivariable analysis demonstrated a dominant effect of the C allele of eNOS SNP -786 T/C on cardiac instability in patients with aSAH. A lower Glasgow Coma Scale score and a history of ischemic vascular disease were also associated with cardiac instability. Furthermore, cardiac instability independently predicted poor functional outcome upon discharge from the hospital.

CONCLUSIONS

The C allele of the eNOS SNP -786 T/C was independently associated with an increased risk for cardiac instability following aSAH. Cardiac instability itself was a risk factor for an unfavorable functional outcome upon discharge from the hospital.

Hypertension After Severe Traumatic Brain Injury: Friend or Foe?

Traumatic brain injury (TBI) is a major public health problem, with severe TBI contributing to a large number of deaths and disability worldwide. Early hypotension has been linked with poor outcomes following severe TBI, and guidelines suggest early and aggressive management of hypotension after TBI. Despite these recommendations, no guidelines exist for the management of hypertension after severe TBI, although observational data suggests that early hypertension is also associated with an increased risk of mortality after severe TBI. The purpose of this review is to discuss the underlying pathophysiology of hypertension after TBI, provide an overview of the current clinical data on early hypertension after TBI, and discuss future research that should test the benefits and harms of treating high blood pressure in TBI patients.

Brain-Heart Interaction: Cardiac Complications After Stroke

Neurocardiology is an emerging specialty that addresses the interaction between the brain and the heart, that is, the effects of cardiac injury on the brain and the effects of brain injury on the heart. This review article focuses on cardiac dysfunction in the setting of stroke such as ischemic stroke, brain hemorrhage, and subarachnoid hemorrhage. The majority of post-stroke deaths are attributed to neurological damage, and cardiovascular complications are the second leading cause of post-stroke mortality. Accumulating clinical and experimental evidence suggests a causal relationship between brain damage and heart dysfunction. Thus, it is important to determine whether cardiac dysfunction is triggered by stroke, is an unrelated complication, or is the underlying cause of stroke. Stroke-induced cardiac damage may lead to fatality or potentially lifelong cardiac problems (such as heart failure), or to mild and recoverable damage such as neurogenic stress cardiomyopathy and Takotsubo cardiomyopathy. The role of location and lateralization of brain lesions after stroke in brain-heart interaction; clinical biomarkers and manifestations of cardiac complications; and underlying mechanisms of brain-heart interaction after stroke, such as the hypothalamic-pituitary-adrenal axis; catecholamine surge; sympathetic and parasympathetic regulation; microvesicles; microRNAs; gut microbiome, immunoresponse, and systemic inflammation, are discussed.

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.

Characterizing the relationship between systemic inflammatory response syndrome and early cardiac dysfunction in traumatic brain injury

Systolic dysfunction was recently described following traumatic brain injury (TBI), and systemic inflammation may be a contributing mechanism. Our aims were to 1) examine the association between the early systemic inflammatory response syndrome (SIRS) and systolic cardiac dysfunction following TBI, and 2) describe the longitudinal change in SIRS criteria, cardiac function, and hemodynamic parameters during the first week of hospitalization. We used a secondary analysis of a prospective cohort study examining cardiac function (with transthoracic echocardiography on the first day and serially over the first week of hospitalization) in 32 moderate-severe isolated TBI patients, and quantified the admission and daily SIRS response to injury. We determined the association of admission SIRS and systolic dysfunction following TBI. Admission SIRS was present in 7 (21%) patients and was associated with systolic dysfunction on multivariable analysis (relative risk 4.01; 95% 1.16-13.79, p = .028). Both SIRS criteria and systolic cardiac function improved over the first week of hospitalization. In conclusion, early SIRS is common among patients with moderate-severe TBI, and the presence of SIRS criteria on admission is associated with systolic cardiac dysfunction following TBI.

Association of Early Hemodynamic Profile and the Development of Systolic Dysfunction Following Traumatic Brain Injury

BACKGROUND

While systolic dysfunction has been observed following traumatic brain injury (TBI), the relationship between early hemodynamics and the development of systolic dysfunction has not been investigated. Our study aimed to determine the early hemodynamic profile that is associated with the development of systolic dysfunction after TBI.

METHODS

We conducted a prospective cohort study among patients under 65 years old without cardiac comorbidities who sustained moderate-severe TBI. Transthoracic echocardiography was performed within the first day after TBI to assess for systolic dysfunction. Hourly systolic blood pressure (SBP), mean arterial pressure (MAP), heart rate, and confounding clinical variables (sedatives, fluid balance, vasopressors, and osmotherapy) were collected during the first 24 h following admission. Multivariable linear mixed models assessed the early hemodynamic profile in patients who developed systolic dysfunction, compared to patients who did not develop systolic dysfunction.

RESULTS

Thirty-two patients were included, and 7 (22 %) developed systolic dysfunction after TBI. Patients who developed systolic dysfunction experienced early elevation of SBP, MAP, and heart rate, compared to patients who did not develop systolic dysfunction (p < 0.01 for all comparisons). Patients who developed systolic dysfunction experienced a greater rate of decrease in SBP [-10.2 mmHg (95 % CI -16.1, -4.2)] and MAP [-9.1 mmHg (95 % CI -13.9, -4.3)] over the first day of hospitalization, compared to patients who did not develop systolic dysfunction (p < 0.01 for both comparisons). All sensitivity analyses revealed no substantial changes from the primary model.

CONCLUSIONS

Patients who develop systolic dysfunction following TBI have a distinctive hemodynamic profile, with early hypertension and tachycardia, followed by a decrease in blood pressure over the first day after TBI. This profile suggests an early maladaptive catecholamine-excess state as a potential underlying mechanism of TBI-induced systolic dysfunction.

Copeptin and NT-proBNP for prediction of all-cause and cardiovascular death in ischemic stroke

OBJECTIVE

To evaluate long-term mortality in patients with acute ischemic stroke (AIS) by exploring the correlation between death and plasma concentrations of copeptin and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a cohort study.

METHODS

In a prospective, multicenter observational study of 4,215 patients with AIS, copeptin and NT-proBNP levels were measured with a standardized method when patients were admitted to hospital. The primary endpoint was all-cause mortality or cardiovascular disease (CVD) mortality within 1 year.

RESULTS

During a follow-up period, 906 patients (20.1%, 95% confidence interval [CI] 18.9-21.2) died, including 589 cases of CVD mortality (13.1%, 95% CI 12.1-14.0). With the use of a multivariate analysis, both markers were found to have prognostic value in the same model (CVD mortality: odds ratio [OR] for fourth quartile of copeptin and NT-proBNP 1.68 and 2.58, 95% CI 1.22-2.49 and 1.76-4.05, respectively; all-cause mortality: OR for fourth quartile of copeptin and NT-proBNP 1.48 and 2.47, 95% CI 1.22-2.03 and 1.68-3.95, respectively). In a receiver operating characteristics analysis of CVD mortality, the area under the curve varied from 0.80 to 0.83 (95% CI 0.79-0.87) when the index of NT-proBNP was added and increased to 0.86 (95% CI 0.83-0.90) when both markers were added.

CONCLUSIONS

Copeptin and NT-proBNP may be useful independent prognostic markers of all-cause or CVD mortality in Chinese patients with AIS.

The Neurocardiogenic Spectrum in Subarachnoid Hemorrhage: A Case Report and Review of the Literature

A 36-year-old man was brought to our emergency department after successful resuscitation of out-of-hospital cardiac arrest with the whole spectrum of neurocardiogenic effects in subarachnoid hemorrhage: electrocardiographic changes, regional wall motion abnormalities, and elevations of cardiac enzymes. Coronary angiography revealed normal coronary arteries but showed the midventricular type of Takotsubo cardiomyopathy in the left ventriculography. Subsequently, cerebral computed tomography revealed diffuse subarachnoid hemorrhage and generalized cerebral edema with brain herniation. Brain death was diagnosed. This case highlights the possibility of an acute cerebral illness (especially subarachnoid hemorrhage) as an underlying cause of cardiac abnormalities mimicking myocardial ischemia.

Neurocardiology

Neurocardiology refers to the interplay between the nervous system and the cardiovascular system. Stress-related cardiomyopathy exemplifies the brain-heart connection and occurs in several conditions with acute brain injury that share oversympathetic activation. The brain's influences on the heart can include elevated cardiac markers, arrhythmias, repolarization abnormalities on electrocardiogram, myocardial necrosis, and autonomic dysfunction. The neurogenic stunned myocardium in aneurysmal subarachnoid hemorrhage represents one end of the spectrum, and is associated with an explosive rise in intracranial pressure that results in excess catecholamine state and possibly CBN. A brain-heart link is more known to cardiologists than neurologists. This chapter provides some insight into the pathophysiology of these pathologic neurocardiac states and their most appropriate management relevant to neurologists.

LPS Pretreatment Provides Neuroprotective Roles in Rats with Subarachnoid Hemorrhage by Downregulating MMP9 and Caspase3 Associated with TLR4 Signaling Activation

Subarachnoid hemorrhage (SAH), as a severe brain disease, has high morbidity and mortality. SAH usually induced neurological dysfunction or death and the treatment is far from satisfaction. Here, we investigated the effect of low dose of LPS pretreatment and underlying molecular mechanism in rat SAH model. Firstly, SAH model was induced by prechiasmal cistern injection method (SAH1) and common carotid artery-prechiasmal cistern shunt method (SAH2), respectively, to select the more suitable SAH model. At 6, 12, 24, 48, and 72 h after SAH, brain injury including neurological dysfunction, blood-brain barrier disruption, brain edema, and cell apoptosis were detected. And the expression of MMP9, HMGB1/TLR4, and caspase3 in cortex were also explored. Then, SB-3CT, an inhibitor of MMP9, was administrated to investigate the exact function of MMP9 in the brain injury at 24 h after SAH. Moreover, low dose of LPS was used to verify whether it had nerve protection after SAH and the mechanism involving in MMP9 and caspase 3 was investigated. Our results showed SAH1 seems to be the most suitable SAH model. In addition, MMP9 activated by HMGB1/TLR4 may promote or aggravate brain injury, while inhibiting MMP9 via SB-3CT exerted a neuroprotective effect. Moreover, LPS improved the neurological dysfunction, reduced Evans blue extravasation and brain edema, and inhibited cell apoptosis of cortex in rats with brain injury induced by SAH. Importantly, LPS pretreatment increased the expression level of TLR4, and decreased the level of MMP9 and caspase3. Therefore, the present study revealed that low dose of LPS pretreatment could provide neuroprotective effects on brain injury caused by SAH via downregulating MMP9 and caspase3 and activating TLR4 signal pathway.

Clinical and Echocardiographic Characteristics of Acute Cardiac Dysfunction Associated With Acute Brain Hemorrhage - Difference From Takotsubo Cardiomyopathy

BACKGROUND

Cardiac dysfunction (CD) associated with brain hemorrhage is similar to that with takotsubo cardiomyopathy but still not well understood. We aimed to investigate the clinical and echocardiographic findings of acute CD (ACD) related to brain hemorrhage.

METHODS AND RESULTS

Between 2013 and 2014, consecutive patients diagnosed with spontaneous and traumatic brain hemorrhage were prospectively enrolled. Electrocardiography, cardiac enzymes, and echocardiography were performed. Left ventricular (LV) systolic dysfunction on echocardiography was defined as ACD related to brain hemorrhage when all the following conditions were satisfied: abnormal ECG and cardiac troponin level, LV wall motion abnormality or decreased LV systolic function on echocardiography, and no previous history of cardiac disease. Otherwise, LV dysfunction was considered to be other CD unrelated to brain hemorrhage. In a total of 208 patients, 15 (7.2%) showed ACD. Of them, 8 patients were men and 8 showed apex-sparing LV hypokinesia and 9 died in hospital. Other cardiac abnormalities observed in the study patients were NT-proBNP elevation (n=123), QT interval prolongation (n=95), LV hypertrophy (n=89), and troponin I elevation (n=47). There were 36 in-hospital deaths (17.3%). Glasgow coma score and ACD were independently associated with in-hospital death.

CONCLUSIONS

ACD was observed in patients with various brain hemorrhages. Unlike takotsubo cardiomyopathy, high proportions of male sex, apex-sparing LV dysfunction, and in-hospital death were observed for ACD associated with brain hemorrhage. (Circ J 2016; 80: 2026-2032).