CONCOMITANT CEREBROVASCULAR ACCIDENT AND NON-ST ELEVATED MYOCARDIAL INFARCTION SECONDARY TO AIR EMBOLI

Abstract

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Cerebral air emboli (CAE) are an uncommon phenomenon that may cause devastating neurologic insult including cerebrovascular accident (CVA), anoxic brain injury, and death [1]. Coronary air emboli may cause cardiac injury, including ST-elevated myocardial infarction (STEMI) and non-ST elevated myocardial infarction (NSTEMI) [2]. Here, we present a rare case of concomitant CVA and NSTEMI secondary to air emboli as a complication of hemodialysis (HD) catheter access. CASE PRESENTATION: A 74-year-old male with a past medical history of end-stage renal disease on HD presented to the emergency department after becoming unresponsive and seizing during HD. He was intubated for airway protection and anti-epileptic medication was administered. Head computed tomography (CT) revealed bubbles of air in the right frontal lobe and medial right temporal fossa, suggestive of either intra-arterial injection of air or right-to-left cardiac or pulmonary shunt. The patient underwent transthoracic echocardiogram with injection of agitated saline which did not reveal intra-cardiac or intra-pulmonary shunt. Brain magnetic resonance imaging (MRI) showed acute right frontal lobe infarct. Neurology evaluated the patient and recommended standard secondary CVA preventive measures and continuation of anti-epileptic medication.The patient also had elevated troponin levels, peaking at 4.7 ng/dL, with inferolateral ST changes consistent with NSTEMI. Cardiology initiated heparin anticoagulation and performed left heart catheterization (LHC). LHC revealed no significant coronary artery disease, furthering evidence that his NSTEMI was due to coronary air emboli. The patient improved clinically without residual neurologic deficits. As no intra-cardiac or intra-pulmonary shunts were identified on TTE, the air emboli were attributed to either occult shunting processes or accidental intra-arterial injection of air. DISCUSSION: Air emboli may enter arterial circulation in many ways, such as arterial line access or trauma. Venous air emboli are possible if an intra-cardiac or intra-pulmonary shunt exists, allowing migration of air from the venous to arterial circulation [1]. This is diagnosed using TTE with visualization of air bubbles in the left heart following agitated saline injection. Treatment of both coronary and cerebral air emboli includes volume resuscitation to increase intravenous pressure and prevent further entry of air emboli. Hyperbaric oxygen therapy may be considered if there are residual neurologic deficits [2]. Otherwise, limited data exists for air emboli treatment, and CVA and NSTEMI should be managed according to current treatment guidelines [2,3]. CONCLUSIONS: Air emboli as a cause of morbidity and mortality is a rare anomaly. Complications of air emboli must be considered in patients exhibiting symptoms or signs of neurologic or cardiac injury during and after medical procedures involving vascular access. REFERENCE #1: Sviri S, Woods WPD, Van Heerden PV. Air embolism; A case series and review. Critical care and resuscitation: Journal of the Australasian Academy of Critical Care Medicine. 2005;6(4):271-6. REFERENCE #2: Waheed TA, Nasir UD, Anthony, Nazir S. Air Embolism and St Elevation Myocardial Infarction: A Systematic Review. Circulation. 2020;142(A14896) REFERENCE #3: Mishra R, Reddy P, Khaja M. Fatal Cerebral Air Embolism: A Case Series and Literature Review. Case Reports in Critical Care. 2016;20163425321. doi:doi.org/10.1155/2016/3425321 DISCLOSURES: No relevant relationships by Amanda Cecchini, source=Web Response No relevant relationships by Roger McSharry, source=Web Response No relevant relationships by Krupa Solanki, source=Web Response