(775) Neurogenic Stunned Myocardium Following Ventriculoperitoneal Shunt Failure

Introduction: Myocardial stun is uncommon in children, occurring in congenital heart disease, cardiac surgery, or inflammatory syndromes. Neurogenic stunned myocardium (NSM) is rare and likely under-recognized, characterized by reversible cardiac dysfunction secondary to severe neurologic insult and resulting catecholamine surge. We report a case of NSM secondary to ventriculoperitoneal (VP) shunt failure.

Description: This was a 6-month-old male with prematurity-related necrotizing enterocolitis status post hemicolectomy and colonostomy, and intraventricular hemorrhage status post-VP shunt. During colonic re-anastomosis, a subgaleal fluid collection was identified with concern for VP shunt dysfunction.
Postoperatively he developed diffuse ST segment elevation with elevated troponin and depressed left ventricular function with moderate mitral valve regurgitation. He had a cardiac arrest and ventricular arrhythmia requiring intervention to achieve return of spontaneous circulation. Subsequent cardiac MRI showed normal coronaries and a small patent foramen ovale (PFO). Head CT showed worsening hydrocephalus. He underwent externalization of VP shunt with immediate neurologic improvement. Cardiac function, EKG, and troponin normalized within 48 hours.

Discussion: NSM is rare in pediatrics, reported secondary to intracranial hemorrhage, TBI, or surgery, but not following VP shunt failure. The underlying mechanism is due to hypoxic and reperfusion injury of myocardial cells from hypercontractility in the context of a catecholamine surge secondary to cerebral injury. Clinically it is characterized by non-specific ST segment changes with variable cardiac function, with reversibility assuming survival.
While coronary embolism leading to myocardial infarction was considered given presence of DVT with PFO, normal coronaries and perfusion on MRI with reversibility of dysfunction suggest NSM as more likely. NSM can be challenging to recognize given the similarities to MI and requires a high index of suspicion in patients with no cardiac history, new cardiac dysfunction, and intracranial pathology. Our case highlights a unique presentation of NSM and the challenges in diagnosis for pediatric populations.