Cardiological evaluation after cerebral ischaemia

Inhibitory Effect of Lactobacillus delbrueckii subsp. bulgaricus KSFY07 on Kappa-Carrageenan-Induced Thrombosis in Mice and the Regulation of Oxidative Damage

A mouse thrombosis model was established by kappa-carrageenan to observe the inhibitory effect of Lactobacillus delbrueckii subsp. bulgaricus KSFY07 (LDSB-KSFY07) on thrombosis and the oxidative stress response. Mouse serum, liver tissue-related indicators, and intestinal microbial composition were measured by examining the expression of microbes in mouse faeces using a biochemical kit, slice observations, and quantitative polymerase chain reaction (qPCR) experiments. The results showed that LDSB-KSFY07 effectively reduced the degree of black tail in thrombotic mice, increased activated partial thromboplastin time (APTT), and decreased thrombin time (TT), fibrinogen (FIB), and prothrombin time (PT) in thrombotic mice. LDSB-KSFY07 was also able to reduce malondialdehyde (MDA) levels and increase superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) levels in the serum and liver tissues of thrombotic mice. Pathological observations showed that LDSB-KSFY07 reduced liver tissue lesions and tail vein thrombosis. Further, experimental results showed that LDSB-KSFY07 was able to upregulate the mRNA expression of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD, and GSH-Px in the liver tissue of thrombotic mice. Moreover, LDSB-KSFY07 was also able to downregulate the mRNA expression of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in tail vein vascular tissue. Meanwhile, LDSB-KSFY07 could raise plasminogen activator inhibitor-1 (PAI-1) mRNA expression and reduce tissue plasminogen activator (t-PA) expression in heart and tail vein vascular tissues of thrombotic mice. A mouse faeces examination revealed that LDSB-KSFY07 could also upregulate Bacteroides, Lactobacterium, and Bifidobacterium microbial expression and downregulate Firmicutes expression in the gut. These results indicate that LDSB-KSFY07 was able to inhibit mouse thrombosis and reduce liver oxidative stress damage in thrombus mice and show that high concentrations of LDSB-KSFY07 provided a better response similar to that of the drug heparin.

Neurological update: use of cardiac troponin in patients with stroke

Cardiac troponin is a specific and sensitive biomarker to identify and quantify myocardial injury. Myocardial injury is frequently detected after acute ischemic stroke and strongly associated with unfavorable outcomes. Concomitant acute coronary syndrome is only one of several possible differential diagnoses that may cause elevation of cardiac troponin after stroke. As a result, there are uncertainties regarding the correct interpretation and optimal management of stroke patients with myocardial injury in clinical practice. Elevation of cardiac troponin may occur as part of a 'Stroke-Heart Syndrome'. The term 'Stroke-Heart Syndrome' subsumes a clinical spectrum of cardiac complications after stroke including cardiac injury, dysfunction, and arrhythmia which may relate to disturbances of autonomic function and the brain-heart axis. In this review, we provide an up-to-date overview about prognostic implications, mechanisms, and management of elevated cardiac troponin levels in patients with acute ischemic stroke.

Myocardial injury in acute ischemic stroke

Since antiquity, the interaction of brain and heart has inspired physicians and philosophers. Today, our knowledge has vastly improved, but the exact way of their interaction still holds many secrets to reveal. The interaction between brain and heart merits particular attention in the aftermath of a sudden injury to the brain-like acute ischemic stroke (AIS). This narrative review gives an overview of current knowledge on frequency, prognosis, and potential pathophysiological mechanisms of myocardial injury following AIS.

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.

Regional Disparities of Left Atrial Appendage Wall Contraction in Patients With Sinus Rhythm and Atrial Fibrillation

BACKGROUND

Patients with atrial fibrillation (AF) exhibit impaired left atrial appendage (LAA) function. However, regional characteristics of LAA function in patients with AF are not defined.

METHODS

Consecutive patients (n = 1,195) undergoing transesophageal echocardiography at a university hospital were included. Patients were divided into three groups on the basis of their rhythm: sinus rhythm (SR), paroxysmal AF, and permanent or persistent AF. Regional LAA wall velocities were determined using color Doppler tissue imaging, placing regions of interest at the lateral and medial wall of the LAA.

RESULTS

Of the 1,182 patients ultimately included, 691 (59%) were in SR, 371 (32%) had permanent or persistent AF, and 120 (10%) had paroxysmal AF with SR at the time of transesophageal echocardiography. Both lateral and medial LAA wall velocities were lower in patients with AF in comparison with those in SR. Nearly 90% of patients in both groups of patients with AF exhibited a pattern of medial LAA wall velocity greater than lateral LAA wall velocity, in comparison with 20% of patients with SR. The odds ratio for the association of this LAA contraction pattern with AF was 22.14 (95% CI, 12.06-40.64; P < .001). The movement of lateral LAA wall velocity showed the highest correlation with LAA emptying velocity compared with the medial LAA wall (r = 0.67, P < .001).

CONCLUSIONS

Lateral LAA wall velocity is higher than medial LAA wall velocity in patients in SR, which reverses in patients with AF. Assessment of LAA regional wall velocity using Doppler tissue imaging appears to be a promising approach to identify patients with paroxysmal AF.

Is transesophageal echocardiography needed for evaluating tissue-based transient ischemic attack?

Transient ischemic attack (TIA) is a warning signal for stroke. A comprehensive evaluation of TIA may reduce the risk for subsequent stroke. Data on the findings of cardiac evaluation with transesophageal echocardiography (TEE) in patients with TIA are sparse. Our aims were to determine the frequency of TEE performance and to investigate the findings of TEE in patients with TIA based on the new definition of TIA (i.e., transient neurological symptoms without evidence of infarction). During a 4-year period (2011-2014), 1071 patients (mean age, 70 ± 13 years; female, 49.7%) with TIA were included in a prospective study and evaluated. Of 1071 consecutive patients suffering from TIA, 288 patients (27%) underwent TEE. The median time between admission and TEE was 6 days. Patients with TIA who were evaluated by TEE were younger (67 vs. 71 years, P < 0.001) than those who were not evaluated by TEE. They had a higher rate of sensibility disturbance as a TIA symptom (39% vs. 31%, P = 0.012) but a lower rate of previous stroke (15% vs. 25%, P = 0.001) and atrial fibrillation (2% vs. 21%, P < 0.001) than those who did not. Foramen ovale was detected in 71 patients (25.7%), atrial septal aneurysm in 13 patients (4.6%), and severe atherosclerotic plaques (grade 4 and 5) in the aortic arch in 25 patients (8.7%). One patient (0.3%) had a fibroma detected by TEE. In 17 of the 288 patients (6%) who underwent TEE, the indication for anticoagulation therapy was based on the TEE results, and 1 patient with fibroma underwent heart surgery. During hospitalization, 7 patients experienced a subsequent stroke, and 27 patients had a recurrent TIA. At 3 months following discharge, the rates of readmission, stroke, recurrent TIA, and death were 19%, 2.7%, 4.2%, and 1.6%, respectively. The rates of mortality (0.9% vs. 1.8%, P = 0.7), stroke risk (1.9% vs. 3.0%, P = 0.8), and recurrent TIA (5.0% vs. 3.9%, P = 0.8) were similar in patients who underwent TEE and in those who did not. Performing TEE in patients with tissue-based TIA is helpful in detecting cardiac sources for embolism and may indicate for anticoagulation.

[Troponin elevation in ischemic stroke patients]

Cerebrovascular and cardiovascular diseases are major causes of death and disability worldwide. Ischemic stroke is a frequent complication in cardiac diseases and, vice versa, cardiac complications commonly cause early clinical worsening and death after stroke. In the emergency setting, cardiac biomarkers (preferably troponin, cTn) are measured frequently in patients presenting with acute ischemic stroke. The measurement of cTn is recommended by the guidelines for early management of patients with acute ischemic stroke from the American Heart Association. In case of pathologic cTn elevation, physicians are confronted with diagnostic and therapeutic uncertainties. Up-to-date recommendations on interpretation and consecutive actions remain ambiguous because cTn elevations may originate from causes other than acute coronary disease and because clinical signs and symptoms of acute coronary disease may be obscured by neurological deficits of the stroke. The application of modern, high-sensitive cTn assays that detect even minor cTn elevations has rather aggravated the dilemma of how to interpret this finding in patients with ischemic stroke.This article gives an overview on possible mechanisms of the frequently observed cTn elevation in ischemic stroke patients and offers help on interpretation and meaningful actions.

[Heart or brain? Problem patients at the interface between cardiology and neurology]

A large number of patients fall into a category at the interface between heart or brain and are expected to require thorough clinical knowledge from both the cardiological as well as the neurological point of view for further patient-oriented treatment. The current article therefore addresses this important issue and aims to provide important information for clinical decision making for those patients at the interface between heart and brain. Due to the clinical impact, patients with carotid stenosis, a patent foramen ovale or non-valvular atrial fibrillation are described in more detail in this article.

Troponin elevation in acute ischemic stroke (TRELAS)--protocol of a prospective observational trial

Background

Levels of the cardiac muscle regulatory protein troponin T (cTnT) are frequently elevated in patients with acute ischemic stroke and elevated cTnT predicts poor outcome and mortality. The pathomechanism of troponin release may relate to co-morbid coronary artery disease and myocardial ischemia or, alternatively, to neurogenic cardiac damage due to autonomic activation after acute ischemic stroke. Therefore, there is uncertainty about how acute ischemic stroke patients with increased cTnT levels should be managed regarding diagnostic and therapeutic workup.

Methods/Design

The primary objective of the prospective observational trial TRELAS (TRoponin ELevation in Acute ischemic Stroke) is to investigate the frequency and underlying pathomechanism of cTnT elevation in acute ischemic stroke patients in order to give guidance for clinical practice. All consecutive patients with acute ischemic stroke admitted within 72 hours after symptom onset to the Department of Neurology at the Campus Benjamin Franklin of the University Hospital Charité will be screened for cTnT elevations (i.e. >= 0.05 μg/l) on admission and again on the following day. Patients with increased cTnT will undergo coronary angiography within 72 hours. Diagnostic findings of coronary angiograms will be compared with age- and gender-matched patients presenting with Non-ST-Elevation myocardial infarction to the Department of Cardiology. The primary endpoint of the study will be the occurrence of culprit lesions in the coronary angiogram indicating underlying co-morbid obstructive coronary artery disease. Secondary endpoints will be the localization of stroke in the cerebral imaging and left ventriculographic findings of wall motion abnormalities suggestive of stroke-induced global cardiac dysfunction.

Discussion

TRELAS will prospectively determine the frequency and possible etiology of troponin elevation in a large cohort of ischemic stroke patients. The findings are expected to contribute to clarify pathophysiologic concepts of co-morbid cardiac damage in ischemic stroke patients and also to provide a basis for clinical recommendations for cardiac workup of such patients.

Trial registration

clinicaltrials.gov NCT01263964