Background: Myocardial dysfunction has been well described with catastrophic neurological events, such as subarachnoid hemorrhage and brain death. There is very limited data describing myocardial function in the context of traumatic brain injury (TBI), as no prospective study has yet examined this association. The objective of our study was to evaluate cardiac function using echocardiography in patients with clinically important TBI.
Methods: We conducted a prospective observational study of consecutive TBI patients admitted to the intensive care unit. All patients older than 16 years with moderate to severe TBI according to the Glascow Coma Scale (GCS) were eligible for the study. Only patients with a prior history of heart disease or cardiomyopathy or evidence of brain death on admission were excluded. A complete transthoracic echocardiogram was performed within 4 days of admission.
Results: Forty-nine patients (67% males, median age 34 years) were included in the study. Forty-one patients had severe TBI (84%) with a median GCS of six, 44 patients (90%) required mechanical ventilation and 36 (74%) intracranial pressure monitoring. Hospital mortality was 18%. No patients had global left ventricular dysfunction as defined by a left ventricular ejection fraction (LVEF) below 50% (95% CI, 0-0.07). Average LVEF was 65 +/- 4%. Four patients (8%) had regional wall motion abnormalities with preserved LVEF.
Discussion: The main finding of this study is the absence of clinically significant myocardial dysfunction in patients with moderate or severe TBI. Although myocardial dysfunction has been well described in a variety of neurological settings, it is possible that the young age of TBI patients and the absence of cardiovascular risk factors are protective against significant myocardial injury from catecholamine excess.
Conclusions: In a group of patients with clinically important TBI, we did not identify any significant cardiac dysfunction.
Keywords: Echocardiography; Left ventricular ejection fraction; Myocardial dysfunction; Traumatic brain injury.