Myocardial dysfunction in acute traumatic brain injury relieved by surgical decompression

Brain-Heart Axis and the Inflammatory Response: Connecting Stroke and Cardiac Dysfunction

BACKGROUND

In recent years, the mechanistic interaction between the brain and heart has been explored in detail, which explains the effects of brain injuries on the heart and those of cardiac dysfunction on the brain. Brain injuries are the predominant cause of post-stroke deaths, and cardiac dysfunction is the second leading cause of mortality after stroke onset.

SUMMARY

Several studies have reported the association between brain injuries and cardiac dysfunction. Therefore, it is necessary to study the influence on the heart post-stroke to understand the underlying mechanisms of stroke and cardiac dysfunction. This review focuses on the mechanisms and the effects of cardiac dysfunction after the onset of stroke (ischemic or hemorrhagic stroke).

KEY MESSAGES

The role of the site of stroke and the underlying mechanisms of the brain-heart axis after stroke onset, including the hypothalamic-pituitary-adrenal axis, inflammatory and immune responses, brain-multi-organ axis, are discussed.

Sex-related beneficial effects of exercise on cardiac function and rhythm in autistic rats

BACKGROUND

Cardiovascular diseases are prevalent in autistic patients. As exercise is useful in the treatment of medical conditions, this study aimed to identify the effect of low-intensity endurance exercise (LIEE) and moderate-intensity endurance exercise (MIEE) on cardiovascular events in autistic rats.

METHODS

Valproic acid (VPA) was administrated once on gestational day 12.5 to pregnant rats to produce autism-like symptoms in offspring. Thirty-day-old offspring were divided into 12 groups: Male-CTL, Male-VPA, Male-CTL + LIEE, Male-CTL + MIEE, Male-VPA + LIEE, Male-VPA + MIEE, Female-CTL, Female-VPA, Female-CTL + LIEE, Female-CTL + MIEE, Female-VPA + LIEE, and Female-VPA + MIEE. LIEE and MIEE were performed 5 days a week for 30 days. Twenty-four hours after the last exercise session, electrocardiogram and hemodynamic and cardiac function indices were recorded.

RESULTS

The results indicated that +dp/dt max and contractility index (CI) decreased in the Female-VPA group compared to the Female-CTL group. LIEE increased these parameters in the Female-VPA + LIEE group. However, MIEE normalized CI in the Male-VPA + MIEE compared to the Male-VPA group. Tau increased in the Female-VPA group compared to the Female-CTL group and it decreased in the Female-VPA + MIEE group compared to the Female-VPA group. LIEE and MIEE recovered the reduction of heart rate and the increase in P, R, and T amplitudes in Male-VPA group. LIEE and MIEE increased heart rate variability in the Male-VPA and Female-VPA groups.

CONCLUSIONS

The findings showed that LIEE and MIEE alleviated cardiac dysfunction and disturbances in heart rhythm in the autistic offspring. Exercise may be recommended as a routine program for autistic patients to prevent and treat the harmful cardiovascular consequences of autism.

Intracranial Hemorrhage Presenting With ST-Segment Elevation and T-Wave Inversion Concerning for Acute Myocardial Infarction

Acute neurologic injury and increased intracranial pressure are associated with electrocardiographic (ECG) changes that include rhythm disturbances as well as ECG mimics of myocardial ischemia, such as focal or diffuse ST-segment or T-wave abnormalities. Both the mechanism and significance of these ECG changes are not clear. The authors report a case of a patient with a complex medical history who became hypotensive after he presented with acute intracranial hemorrhage. A subsequent ECG showing ST-segment elevation in the inferior and lateral leads was concerning for acute myocardial infarction. ST-segment elevation in the setting of acute intracranial hemorrhage can lead to diagnostic confusion and/or premature narrowing of the differential diagnosis. This case report starts with an example of this exact scenario, provides a concise overview of potential mechanisms, and concludes with several possible strategies that the emergency provider can use to identify this effect in an undifferentiated patient.

Takotsubo cardiomyopathy in post-traumatic brain injury: A systematic review of diagnosis and management

OBJECTIVE

Myocardial dysfunction is a known complication in patients who experience severe stressful events, such as traumatic brain injuries (TBI). One common manifestation is Takotsubo Cardiomyopathy (TC) which can appear concomitantly in patients with haemorrhagic brain injuries. There is often a management dilemma when two conditions with conflicting treatment regimens arise in the same individual. Previous systematic review had highlighted the importance of accurate diagnosis but there is no algorithm to aid decision-making in an emergency trauma setting. A systematic review was performed with the aim of establishing a new algorithm to aid in the diagnosis and management of TC patients with concurrent TBI.

METHODS

We performed a comprehensive search of Pubmed, google scholar, Embase and Cochrane databases using keywords 'traumatic brain injury' and 'head injury' associated with keywords of 'Takotsubo cardiomyopathy,' 'Tako-tsubo cardiomyopathy,' 'stress cardiomyopathy,' 'stunned myocardium,' 'transient-left-ventricular ballooning syndrome,' 'apical ballooning syndrome,' 'myocardial dysfunction' or 'heart failure'. Non traumatic brain injury, blunt cardiac injury or cardiac events from chest trauma were excluded. The search was done between 1st to 4th October 2020 and only articles published after the year 2000 in English were included. Articles were then analysed in-depth. No articles were excluded after analysis to remove reporting bias.

RESULTS

A total of 11 case reports and 7 cohort studies were analysed, giving a total number of 382 patients, with 36% of the patients analysed presenting with subdural haematoma, 27% with subarachnoid haemorrhage and 5% with extradural haematoma. Of the patients who underwent surgical interventions for traumatic brain injuries, 75% survived. 9% of patients in total were reported to have an EF of less than 55% whereas 51% had an EF of equal to or more than 55%. TTE details were not reported in a total of 35% of patients. All case reports which had followed up on their patient's cardiac status with repeated echocardiography had demonstrated a resolution of cardiac function independent of cardiac intervention.

DISCUSSION

Our analysis was limited by the fact that not all papers analysed had reported the parameters we required. However, based on our review, we conclude that most patients with TC demonstrate a resolution of cardiac function independent of cardiac interventions from as fast as a few hours to as long as 6-12 weeks. Therefore, despite high cardiac risks, if neurosurgical intervention is needed, it should be offered to improve the chance of survival as transient cardiomyopathy can be supported with inotropes. We have developed a new algorithm for management of cases of concurrent TBI and TC.

Perioperative cardiovascular changes in patients with traumatic brain injury: A prospective observational study

Background:

Traumatic brain injury (TBI) is an acutely stressful condition. Stress and conglomeration of various factors predispose to the involvement of other organ systems. The stress response from TBI has been associated with cardiovascular complications reflecting as repolarization abnormalities on electrocardiogram (ECG) to systolic dysfunction on echocardiography. However, the perioperative cardiac functions in patients with TBI have not been evaluated.

Methods:

We conducted a prospective observational study in 60 consecutive adult patients of either sex between the age of 10 and 70 years with an isolated head injury who were taken up for decompressive craniectomy as per institutional protocol. ECG and transthoracic echocardiography was carried out preoperatively and then postoperatively within 24–48 h.

Results:

The mean age of our study population was 39 + 13 years with a median Glasgow coma score of 11. A majority (73%) of our patients suffered moderate TBI. Preoperatively, ECG changes were seen in 48.33% of patients. Postoperatively, ECG changes declined and were seen only in 13.33% of the total patients. Similarly, echocardiography demonstrated preoperative systolic dysfunction in 13.33% of the total study population. Later, it was found that systolic function significantly improved in all the patients after surgery.

Conclusion:

Cardiac dysfunction occurs frequently following TBI. Even patients with mild TBI had preoperative systolic dysfunction on echocardiography. Surgical intervention in the form of hematoma evacuation and decompression was associated with significant regression of both ECG and echocardiographic changes.

The Short-Term Effects of Isolated Traumatic Brain Injury on the Heart in Experimental Healthy Rats

BACKGROUND

To date, cardiac dysfunction after traumatic brain injury (TBI) has not been consistent. In this study, we hypothesized that TBI may play a role in the development of new-onset cardiac dysfunction in healthy experimental rats.

MATERIALS AND METHODS

Anesthetized healthy male Sprague-Dawley rats were divided into two groups: a sham-operated control group and a TBI group. The brain was injured with 2.4 atm percussion via a fluid percussion injury model. During the 120 min after TBI, we continuously measured brain parameters, including intracranial pressure (ICP) and cerebral perfusion pressure (CPP), and cardiac parameters, such as heart rate (HR), inter-ventricular septum dimension (IVSD), left ventricular internal dimension diastole (LVIDd), end-diastolic volume (EDV), ejection fraction (EF), fractional shortening (FS), and LV mass diastole (LVd mass) by cardiac echo. On days 1, 3, 7, and 14 after TBI, the brain damage volume was evaluated with triphenyltetrazolium chloride; the physiological parameters of the heart, including HR, IVSd, LVIDd, EDV, EF, FS, and LVd mass, were evaluated with cardiac echo; the morphology of cardiomyocytes was examined by hematoxylin and eosin (HE) and Masson trichrome staining; and the biomarkers of cardiac injury troponin I and B-type natriuretic peptide (BNP) were also examined.

RESULTS

Compared to sham-operated controls, the TBI groups had higher ICP, lower CPP, and higher brain neuronal apoptosis and infarction contusion volume. The impact of TBI on heart function showed hyperdynamic response trends in IVSd, LVIDd, EDV, EF, FS, and LVd mass within 30 min after TBI; however, EF and FS exhibited eventual decreasing trends. Simultaneously, the values of the biomarkers troponin I and BNP were within normal limits, and HE and Mass trichrome staining revealed no significant differences between the sham-operated control group and the TBI group.

CONCLUSIONS

Our results suggest that TBI due to 2.4 atm fluid percussion injury in healthy experimental rats may cause significant damage to the brain and affect the heart function as investigated by cardiac echo but not as investigated by HE and Masson trichrome stainings or troponin I and BNP evaluation.

Cardiac Dysfunction in Adult Patients with Traumatic Brain Injury: A Prospective Cohort Study

BACKGROUND

There are limited data regarding the development of myocardial dysfunction after a traumatic brain injury (TBI). We investigated incidence, risk factors, and prognostic importance of cardiac dysfunction in adult patients admitted to the intensive care unit (ICU) after a moderate to severe TBI.

METHODS

Prospective observational study of consecutive patients admitted to neuro-trauma ICU with moderate to severe TBI from August 2014 to June 2015.

RESULTS

A total of 46 patients were included. Patients' mean (±SD) age was 44.7 (±20.7) years and mean Glasgow Coma Scale value was 5.6 (±3). Motor vehicle accident was the most common mechanism of TBI, with subdural and subarachnoid hemorrhages as the most common pathologies. Cardiac dysfunction developed in 6 of 46 (13%) patients. Patients with cardiac dysfunction had higher prevalence of diabetes mellitus (50% vs. 10%, P = 0.03) and higher proportion of electrocardiogram abnormalities (83% vs. 27%, P = 0.02) compared to the patients without cardiac dysfunction. Mean Glasgow Coma Scale scores were not significantly different between patients who developed cardiac dysfunction from those who did not (5.5 vs. 5.6, P = 0.95). Requirement for vasopressor support (33.3% vs. 40%, P = 1.0) and median ventilator days (5.2 vs. 4.7, P = 0.9) were similar between patients with and without cardiac dysfunction. There were no significant differences in hospital lengths of stay (12.3 vs. 13.8 days, P = 0.34) and hospital mortality (33% vs. 17.5%, P = 0.58) between the two groups.

CONCLUSIONS

Cardiac dysfunction occurs in patients after moderate to severe TBI, with mild to moderate reduction in left ventricular ejection fraction. Patients who developed cardiac dysfunction after TBI had a higher prevalence of diabetes mellitus and higher proportion of abnormalities in electrocardiograms. Development of cardiac dysfunction was not associated with adverse clinical outcomes.

Early Systolic Dysfunction Following Traumatic Brain Injury: A Cohort Study

OBJECTIVE

Prior studies have suggested that traumatic brain injury may affect cardiac function. Our study aims were to determine the frequency, longitudinal course, and admission risk factors for systolic dysfunction in patients with moderate-severe traumatic brain injury.

DESIGN

Prospective cohort study.

SETTING

Level 1 trauma center.

MEASUREMENTS

Transthoracic echocardiogram within 1 day and over the first week after moderate-severe traumatic brain injury; transthoracic echocardiogram within 1 day after mild traumatic brain injury (comparison group).

MEASUREMENTS AND MAIN RESULTS

Systolic function was assessed by transthoracic echocardiogram, and systolic dysfunction was defined as fractional shortening less than 25%. Multivariable Poisson regression models examined admission risk factors for systolic dysfunction. Systolic function in 32 patients with isolated moderate-severe traumatic brain injury and 32 patients with isolated mild traumatic brain injury (comparison group) was assessed with transthoracic echocardiogram. Seven (22%) moderate-severe traumatic brain injury and 0 (0%) mild traumatic brain injury patients had systolic dysfunction within the first day after injury (p < 0.01). All patients with early systolic dysfunction recovered in 1 week. Younger age (relative risk, 0.87; 95% CI, 0.79-0.94; for 1 yr increase in age) and lower admission Glasgow Coma Scale score (relative risk, 0.34; 95% CI, 0.20-0.58; for one unit increase in Glasgow Coma Scale) were independently associated with the development of systolic dysfunction among moderate-severe traumatic brain injury patients.

CONCLUSIONS

Early systolic dysfunction can occur in previously healthy patients with moderate-severe traumatic brain injury, and it is reversible over the first week of hospitalization. Younger age and lower admission Glasgow Coma Scale score are independently associated with the development of systolic dysfunction after moderate-severe traumatic brain injury.

Takotsubo Cardiomyopathy in Traumatic Brain Injury

BACKGROUND

Takotsubo cardiomyopathy (TC) is a well-known complication after aneurysmal subarachnoid hemorrhage and has been rarely described in patients with traumatic brain injury (TBI).

METHODS

Case report and review of literature.

RESULTS

Here, we report a 73-year-old woman with mild traumatic brain injury (TBI) presenting in cardiogenic shock. Takotsubo cardiomyopathy (TC) was diagnosed by repeated echocardiography. Cardiovascular support by inotropic agents led to hemodynamic stabilization after initiation of levosimendan. Cardiac function fully recovered within 21 days. We performed an in-depth literature review and identified 16 reported patients with TBI and TC. Clinical course and characteristics are discussed in the context of our patient.

CONCLUSION

Takotsubo cardiomyopathy is under-recognized after TBI and may negatively impact outcome if left untreated.

Cardiac Dysfunction After Neurologic Injury: What Do We Know and Where Are We Going?

Recent literature has implicated severe neurologic injuries, such as aneurysmal subarachnoid hemorrhage, as a cause of cardiac dysfunction, impaired hemodynamic function, and poor outcomes. Mechanistic links between the brain and the heart have been explored in detail over the past several decades, and catecholamine excess, neuroendocrine dysfunction, and unchecked inflammation all likely contribute to the pathophysiologic process. Although cardiac dysfunction has also been described in other disease paradigms, including septic shock and thermal injury, there is likely a common underlying pathophysiology. In this review, we will examine the pathophysiology of cardiac dysfunction after neurologic injury, discuss the evidence surrounding cardiac dysfunction after different neurologic injuries, and suggest future research goals to gain knowledge and improve outcomes in this patient population.

Traumatic brain injury has not prominent effects on cardiopulmonary indices of rat after 24 hours: hemodynamic, histopathology, and biochemical evidence

BACKGROUND

Accidents are the second reason for mortality and morbidity in Iran. Among them, brain injuries are the most important damage. Clarification of the effects of brain injuries on different body systems will help physicians to prioritize their treatment strategies. In this study, the effect of pure brain trauma on the cardiovascular system and lungs 24 hours post trauma was assessed.

METHODS

Male Wistar rats (n = 32) were divided into sham control and traumatic brain injury (TBI) groups. In TBI animals, under deep anesthesia, a blow to the head was induced by the fall of a 450 g weight from 2 m height. Twenty four hours later, heart electrocardiogram and functional indices, cardiac troponin I, IL-6, TNF-, IL-I in tissue and serum, and the histopathology of heart and lung were assessed.

RESULTS

The results showed that none of the functional, biochemical, inflammatory, and histopathology indices was statistically different between the two groups at 24 hours post TBI. Indices of impulse conduction velocity in atrium (P wave duration and P-R interval) were significantly longer in the TBI group.

CONCLUSION

Overall, no important functional and histopathologic disturbances were found in heart and lung of TBI group after 24 hours. If the data is reproduced in human studies, the medical team could allocate their priority to treatment of brain disorders of the victim in the first 24 hours of pure TBI and postpone extensive assessment of heart and lung health indices to later time, thus reducing patient and health system expenditures.