B-type natriuretic peptide release and left ventricular filling pressure assessed by echocardiographic study after subarachnoid hemorrhage: a prospective study in non-cardiac patients

Relation between brain natriuretic peptide and delayed cerebral ischemia in patients with aneurysmalsubarachnoid hemorrhage

BACKGROUND

Brain natriuretic peptide (BNP), often used to evaluate degree of heart failure, has been implicated in fluid dysregulation and inflammation in critically-ill patients. Twenty to 30% of patients with aneurysmal subarachnoid hemorrhage (aSAH) will develop some degree of neurogenic stress cardiomyopathy (NSC) and in turn elevation of BNP levels. We sought to explore the association between BNP levels and development of delayed cerebral ischemia (DCI) in patients with aSAH.

METHODS

We retrospectively evaluated the records of 149 patients admitted to the Neurological Intensive Care Unit between 2006 and 2015 and enrolled in an existing prospectively maintained aSAH database. Demographic data, treatment and outcomes, and BNP levels at admission and throughout the hospital admission were noted.

RESULTS

Of the 149 patients included in the analysis, 79 developed DCI during their hospital course. We found a statistically significant association between DCI and the highest recorded BNP (OR 1.001, 95% CI-1.001-1.002, p = 0.002). The ROC curve analysis for DCI based on BNP showed that the highest BNP level during hospital admission (AUC 0.78) was the strongest predictor of DCI compared to the change in BNP over time (AUC 0.776) or the admission BNP (AUC 0.632).

CONCLUSION

Our study shows that DCI is associated not only with higher baseline BNP values (admission BNP), but also with the highest BNP level attained during the hospital course and the rapidity of change or increase in BNP over time. Prospective studies are needed to evaluate whether routine measurement of BNP may help identify SAH patients at high risk of DCI.

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.

Brain-Heart Axis and Biomarkers of Cardiac Damage and Dysfunction after Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Cardiac complications after a stroke are the second leading cause of death worldwide, affecting the treatment and outcomes of stroke patients. Cardiac biomarkers such as cardiac troponin (cTn), brain natriuretic peptide (BNP), and N-terminal pro-brain natriuretic peptide (NT-proBNP) have been frequently reported in patients undergoing a stroke. The aim of the present study is to meta-analyze the relationship between changes in such cardiac biomarkers and stroke and to present a systematic review of the previous literature, so as to explore the brain-heart axis.

METHODS

We searched four online databases pertinent to the literature, including PubMed, Embase, the Cochrane Library, and the Web of Science. Then, we performed a meta-analysis to investigate changes in cTn, BNP, and NT-proBNP associated with different types of stroke.

RESULTS AND CONCLUSIONS

A significant increase in cTnI concentration was found in patients exhibiting a brain hemorrhage. BNP increased in cases of brain infarction, while the NT-proBNP concentration was significantly elevated in patients suffering an acute ischemic stroke and brain hemorrhage, indicating cardiac damage and dysfunction after a stroke. Our analysis suggests that several potential mechanisms may be involved in the brain-heart axis. Finally, clinicians should pay careful attention to monitoring cardiac function in the treatment of cerebrovascular diseases in order to provide a timely and more accurate treatment.

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.

Impact of echocardiographic wall motion abnormality and cardiac biomarker elevation on outcome after subarachnoid hemorrhage: a meta-analysis

Cardiac abnormalities (echocardiographic wall motion abnormality (WMA), biomarker elevation of cardiac troponin (cTn), B-type natriuretic peptide (BNP), or N-terminal prohormone of B-type natriuretic peptide (NT-proBNP)) frequently occur after subarachnoid hemorrhage (SAH). The clinical significance of cardiac abnormalities after SAH remains controversial. This meta-analysis was performed to assess the association between cardiac abnormalities and patient outcomes, including delayed cerebral ischemia (DCI), poor outcome, and death in SAH patients. PubMed and Embase were searched for observational studies reporting an association between cardiac abnormalities and outcome after SAH that were published before 31 December 2017. We extracted data regarding patient characteristics, cardiac abnormalities, and outcome measurements (DCI, poor outcome, or death). Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Twenty-six studies involving 3917 patients were included in our data analysis. WMA showed significant associations with higher rates of DCI (RR, 2.03; 95% CI, 0.99-4.15), poor outcome (RR, 1.45; 95% CI, 1.08-1.93), and death (RR, 2.54; 95% CI, 1.59-4.05). cTn elevation was associated with an increased risk of DCI (RR, 1.48; 95% CI, 1.23-1.79), poor outcome (RR, 1.85; 95% CI, 1.49-2.30), and death (RR, 2.68; 95% CI, 2.19-3.27). Elevation of BNP or NT-proBNT was significantly associated with higher rates of DCI (RR, 1.87; 95% CI, 1.16-3.02). WMA and elevation of cTn, BNP, and NT-proBNP in SAH patients are associated with an increased risk of DCI, poor outcome, and death after SAH.

The Relationships Between BNP and Neurocardiac Injury Severity, Noninvasive Cardiac Output, and Outcomes After Aneurysmal Subarachnoid Hemorrhage

INTRODUCTION

Neurocardiac injury, a type of myocardial dysfunction associated with neurological insult to the brain, occurs in 31-48% of aneurysmal subarachnoid hemorrhage (aSAH) patients. Cardiac troponin I (cTnI) is commonly used to diagnose neurocardiac injury. Brain natriuretic peptide (BNP), another cardiac marker, is more often used to evaluate degree of heart failure. The purpose of this study was to examine the relationships between BNP and (a) neurocardiac injury severity according to cTnI, (b) noninvasive continuous cardiac output (NCCO), and (c) outcomes in aSAH patients.

METHOD

This descriptive longitudinal study enrolled 30 adult aSAH patients. Data collected included BNP and cTnI levels and NCCO parameters for 14 days and outcomes (modified Rankin Scale [mRS] and mortality) at discharge and 3 months. Generalized estimating equations were used to evaluate associations between BNP and cTnI, NCCO, and outcomes.

RESULTS

BNP was significantly associated with cTnI. For every 1 unit increase in log BNP, cTnI increased by 0.05 ng/ml ( p = .001). Among NCCO parameters, BNP was significantly associated with thoracic fluid content ( p = .0003). On multivariable analyses, significant associations were found between BNP and poor mRS. For every 1 unit increase in log BNP, patients were 3.16 times more likely to have a poor mRS at discharge ( p = .021) and 5.40 times more likely at 3 months ( p < .0001).

CONCLUSION

There were significant relationships between BNP and cTnI and poor outcomes after aSAH. BNP may have utility as a marker of neurocardiac injury and outcomes after aSAH.

Advanced monitoring of systemic hemodynamics in critically ill patients with acute brain injury

Hemodynamic monitoring is widely used in critical care; however, the impact of such intervention in patients with acute brain injury (ABI) remains unclear. Using PubMed, a systematic review was performed (1966-August 2013), and 118 studies were included. Data were extracted using the PICO approach. The evidence was classified, and recommendations were developed according to the GRADE system. Electrocardiography and invasive monitoring of arterial blood pressure should be the minimal hemodynamic monitoring required in unstable or at-risk patients in the intensive care unit. Advanced hemodynamic monitoring (i.e., assessment of preload, afterload, cardiac output, and global systemic perfusion) could help establish goals that take into account cerebral blood flow and oxygenation, which vary depending on diagnosis and disease stage. Choice of techniques for assessing preload, afterload, cardiac output, and global systemic perfusion should be guided by specific evidence and local expertise. Hemodynamic monitoring is important and has specific indications among ABI patients. Further data are necessary to understand its potential for therapeutic interventions and prognostication.

An observational study of the association between microalbuminuria and increased N-terminal pro-B-type natriuretic peptide in patients with subarachnoid hemorrhage

BACKGROUND

The urinary albumin/creatinine ratio (ACR) is a significant neurologic prognostic predictor in patients with aneurysmal subarachnoid hemorrhage (SAH). B-type natriuretic peptide (BNP) plays an important role in body fluid regulation in patients with SAH. The present study was performed to determine whether ACR was independent predictor for unfavorable neurological outcome and ACR was associated with increased N-terminal pro-BNP (NT-pro-BNP) after SAH.

METHODS

We studied 61 patients undergoing surgery who were admitted within 48 h after aneurysmal SAH onset between July 2008 and June 2010. Hunt and Hess grade and Fisher grade were recorded at admission. The Glasgow Coma Scale (GCS) score was calculated at admission and daily for seven postoperative days. Arterial blood was sampled at admission and for seven postoperative days to determine the PaO2/FIO2 ratio, C-reactive protein level, troponin I level, and NT-pro-BNP level. Urine was sampled at admission and daily for seven postoperative days to determine ACR and vanillylmandelic acid/creatinine ratio (VMACR). Neurological outcomes were assessed at hospital discharge by using the Glasgow Outcome Scale. Receiver operating characteristic curves were constructed for the predictive variables of unfavorable neurological outcomes, and the area under the curve (AUC) was determined. Multivariate logistic regression analyses were performed for the significant predictors of unfavorable neurological outcomes after SAH. Associations with NT-pro-BNP were evaluated by using the Spearman rank correlation test.

RESULTS

Of the 61 patients, 24 had unfavorable outcomes. The prevalence rate of microalbuminuria was 85 % (52/61). The highest NT-pro-BNP levels were above the normal range in 57 of 61 patients (93 %). According to the AUC, the Hunt and Hess grade, GCS score, the highest ACR, and highest VMACR were significant predictors of neurological outcome. Multivariate logistic regression analyses showed that the highest ACR and Hunt and Hess grade are independent prognostic predictors of unfavorable neurological outcomes. The highest NT-pro-BNP significantly correlated with the highest troponin I, highest ACR, and VMACR on admission.

CONCLUSIONS

The highest ACR is an independent prognostic predictor of unfavorable neurological outcomes after SAH. Moreover, plasma NT-pro-BNP elevation may be associated with the development of microalbuminuria.

Tissue Doppler indices of diastolic function in critically ill patients and association with mortality - a systematic review

PURPOSE

Systolic impairment is well reported in critically ill patients but diastolic function has been relatively understudied. The objective of this review was to assess tissue Doppler indices of diastolic function in critically ill patients along with any association with mortality.

METHODS

A systematic review of articles in English using Medline, EMBASE, CINAHL and the Cochrane database of systematic reviews. Search terms included diastolic function, diastolic dysfunction, diastolic abnormal*, diastolic heart failure, diastolic filling, ventricular relaxation, pulmonary artery occlusion pressure, left ventricular filling pressure, cardiac dysfunction, intensive care, critical care, critically ill, critical illness, sepsis and septic shock. Only studies of critically ill adult patients (excluding post-cardiac surgical patients) whose diastolic function was assessed using tissue Doppler imaging were included. Study quality was assessed using a modified version of the Newcastle-Ottawa Scale (NOS).

RESULTS

Nineteen studies were included, with a total of 1365 patients. All trials were observational. There was a large heterogeneity in patient populations and the methodology of tissue Doppler assessment of diastology resulting in a descriptive analysis. Patient groups included severe sepsis or septic shock (5 studies), septic shock (5 studies), systemic inflammatory response syndrome and shock (1 study), septic shock and acute lung injury (1 study), cancer and septic shock (2 studies), general ICU patients (1 study), combined medical and surgical ICU (2 studies) and sub-arachnoid haemorrhage patients (2 studies). Seventeen studies scored 5/6 on the NOS with the remaining two scoring 4/6. Fourteen studies reported on numbers of patients diagnosed with diastolic dysfunction (500/999, mean 50%, range 20-92%). Three studies found that diastolic dysfunction was an independent predictor of mortality.

CONCLUSIONS

Current data shows a large range in the incidence of diastolic dysfunction in this patient population and a variable link with mortality. Future research should focus on the definition of normal values for diastolic function in critically ill patients along with the effects of ICU therapies and consensus criteria for its assessment in this patient population.

Subarachnoid hemorrhage induces an early and reversible cardiac injury associated with catecholamine release: one-week follow-up study

Introduction

The occurrence of cardiac dysfunction is common after subarachnoid hemorrhage (SAH) and was hypothesized to be related to the release of endogenous catecholamines. The aim of this prospective study was to evaluate the relationship between endogenous catecholamine and cardiac dysfunction at the onset and during the first week after SAH.

Methods

Forty consecutive patients admitted for acute SAH without known heart disease were included. Catecholamine plasma concentrations and transthoracic echocardiography (TTE) were documented on admission, on day 1 (D1), and day 7 (D7).

Results

At baseline, 24 patients had a World Federation of Neurosurgical Societies score (WFNS) of one or two; the remaining 16 had a WFNS between three and five. Twenty patients showed signs of cardiac dysfunction on admission, including six with left ventricle (LV) systolodiastolic dysfunction and 14 with pure LV diastolic dysfunction. On admission, norepinephrine, epinephrine, dopamine, B-type Natriuretic Peptide (BNP) and Troponin Ic (cTnI) plasmatic levels were higher in patients with the higher WFNS score and in patients with altered cardiac function (all P <0.05). Among patients with cardiac injury, heart function was restored within one week in 13 patients, while seven showed persistent LV diastolic dysfunction (P = 0.002). Plasma BNP, cTnI, and catecholamine levels exerted a decrease towards normal values between D1 and D7.

Conclusion

Our findings show that cardiac dysfunction seen early after SAH was associated with both a rapid and sustained endogenous catecholamine release and WFNS score. SAH-induced cardiac dysfunction was regressive over the first week and paralleled the normalization of catecholamine concentration.

Impairment of cardiac metabolism and sympathetic innervation after aneurysmal subarachnoid hemorrhage: a nuclear medicine imaging study

Introduction

Although aneurysmal subarachnoid hemorrhage (SAH) is often complicated by myocardial injury, whether this neurogenic cardiomyopathy is associated with the modification of cardiac metabolism is unknown. This study sought to explore, by positron emission tomography/computed tomography, the presence of altered cardiac glucose metabolism after SAH.

Methods

During a 16-month period, 30 SAH acute phase patients underwent myocardial ¹⁸ F- fluorodesoxyglucose positron emission tomography (¹⁸F-FDGPET), ^99mTc-tetrofosmin and ¹²³I-meta-iodobenzylguanidine (¹²³I-mIBG) scintigraphy, respectively, assessing glucose metabolism, cardiac perfusion, and sympathetic innervation. Patients with initial abnormalities were followed monthly for two months for ¹⁸F-FDG, and six months later for ¹²³I-mIBG.

Results

In this SAH population, acute cardiac metabolic disturbance was observed in 83% of patients (n = 25), and sympathetic innervation disturbance affected 90% (n = 27). Myocardial perfusion was normal for all patients. The topography and extent of metabolic defects and innervation abnormalities largely overlapped. Follow-up showed rapid improvement of glucose metabolism in one or two months. Normalization of sympathetic innervation was slower; only 27% of patients (n = 8) exhibited normal ¹²³I-mIBG scintigraphy after six months. Presence of initial altered cardiac metabolism was not associated with more unfavorable cardiac or neurological outcomes.

Conclusions

These findings support the hypothesis of neurogenic myocardial stunning after SAH. In hemodynamically stable acute phase SAH patients, cardiomyopathy is characterized by diffuse and heterogeneous ¹⁸F-FDG and ¹²³I-mIBG uptake defect.

Trial registration

Clinicaltrials.gov NCT01218191. Registered 6 October 2010.

Predictors of increased cumulative serum levels of the N-terminal prohormone of brain natriuretic peptide 4 days after acute spontaneous subarachnoid hemorrhage

Object

The rupture of an intracranial aneurysm is followed by increased intracranial pressure and decreased cerebral blood flow. A major systemic stress reaction follows, presumably to restore cerebral blood flow. However, this reaction can also cause adverse effects, including myocardial abnormalities, which are common and can be serious, and increased levels of natriuretic peptides, especially brain natriuretic peptide (BNP). The association of BNP with fluid and salt balance, vasospasm, brain ischemia, and cardiac injury has been studied but almost exclusively regarding events after admission. Brain natriuretic peptide has also been measured at various time points and analyzed in different ways statistically. The authors approached BNP measurement in a new way; they used the calculated area under the curve (AUC) for the first 4 days to quantitatively measure the BNP load during the first critical part of the disease state. Their rationale was a suspicion that early BNP load is a marker of the severity of the ictus and will influence the subsequent course of the disease by disturbing the fluid and salt balance.

Methods

The study included 156 patients with acute spontaneous subarachnoid hemorrhage (SAH). Mean patient age was 59.8 ± 11.2 years, and 105 (67%) of the patients were female. An aneurysm was found in 138 patients. A total of 82 aneurysms were treated by endovascular coiling, 50 were treated by surgery, and 6 were untreated. At the time of admission, serum samples were collected for troponin-I analysis and for the N-terminal prohormone of BNP (NT-proBNP); daily thereafter, samples were collected for the NT-proBNP analysis. The cumulative BNP load was calculated as the AUC for NT-proBNP during the first 4 days. The following variables were studied in terms of their influence on the AUC for NT-proBNP: sex, age, World Federation of Neurosurgical Societies grade of SAH, Fisher grade, angiographic result, treatment of aneurysm, clinical neurological deterioration, verified infections, vasospasm treatment, and 6-month outcome.

Results

The AUC for NT-proBNP was larger when variables indicated a more severe SAH. These variables were higher Fisher and World Federation of Neurosurgical Societies grades, high levels of troponin-I at admission, an aneurysm, neurological deficits, and infections. The AUC for NT-proBNP was also larger among women, older patients, and patients with poor outcomes. Linear regression showed that the best predicting model for large AUC for NT-proBNP was the combination of the following: female sex, high levels of troponin-I, an aneurysm, neurological deficits, and advanced age.

Conclusions

The cumulative BNP load during the first days after SAH can be predicted by variables describing the severity of the disease already known at the time of admission. This information can be used to identify patients at risk for an adverse course of the disease.

Changes in brain natriuretic peptide are correlated with changes in global end-diastolic volume index

BACKGROUND AND OBJECTIVE

It is believed that the stretch of cardiomyocytes is the most important stimulus of brain natriuretic peptide (BNP) release; however, its correlation with volume status represented by global end diastolic volume index (GEDVI) is less well established. The study aimed to investigate the correlation between the changes in BNP and the changes in GEDVI measured with transpulmonary thermodilution technique.

METHODS

Critically ill patients requiring hemodynamic monitoring (PiCCO system) in a tertiary 18-bed intensive care unit were prospectively enrolled. Hemodynamic variables were measured simultaneously with blood sampling for BNP concentration. Correlations between changes in BNP and changes in GEDVI were tested using pairwise correlation analysis.

RESULTS

A total of 46 patients were included in the study. BNP level (median 4,602 pg/mL; IQR 1,988 to 12,439 pg/mL) was markedly elevated in the study population, but was not correlated with GEDVI (rho=-0.09, P=0.56). The changes in BNP (ΔBNP) showed significant correlation with changes in GEDVI (ΔGEDVI) (Figure 2; rho=0.52, P<0.01). Variables including Age (r=0.43, P=0.002), serum creatinine (r=0.36, P=0.012) and cardiac index (CI) (r=-0.35, P=0.016) were also significantly correlated with logBNP. Other variables such as APACHE II score, central venous pressure (CVP), heart rate (HR), intrathoracic blood volume (ITBVI), extravascular lung water (EVLWI) and systemic vascular resistance index (SVRI) were not significantly correlated with logBNP.

CONCLUSIONS

Changes in BNP concentrations are correlated with changes in GEDVI and serial measurements of BNP concentrations may be a useful tool for monitoring volume status.

Extremely high brain natriuretic peptide does not reflect the severity of heart failure

Brain natriuretic peptide (BNP) is important in the diagnosis and management of heart failure (HF). Sometimes, very high BNP levels encountered in clinical settings seem to be out of proportion to the severity of HF. The authors retrospectively identified 113 patients with 129 admissions with a BNP value >3000 pg/mL regardless of diagnosis. The data set was analyzed using the Student t test and bivariate analysis. Fewer than half of patients were admitted for HF. In 14 patients (10.9%), no signs of HF were found. The BNP level of those with and without HF was similar. There was no difference in BNP level in patients with and without systolic dysfunction or renal dysfunction and between different age groups. Extreme values of BNP do not necessarily correlate with the presence of HF, cardiomyopathy, or kidney dysfunction. When the magnitude of BNP elevation is very high, its clinical significance is limited.

B-type natriuretic levels in critically ill patients: critically misleading?

Although B-type natriuretic peptide (BNP) has been used for the diagnosis of congestive heart failure in many clinical settings, its diagnostic role in critically ill patients remains uncertain. The body of literature suggests that BNP and N-terminal pro-BNP levels are not useful for the diagnosis of systolic or diastolic heart failure in the critically ill, including in patients with brain hemorrhage, due to poor specificity. However, these cardiac peptides may have a more promising prognostic role in this patient population.