RESUMEN
ABSTRACT: Neonatal cardiac masses are uncommon and often not obvious based on physical examination or plain radiography. The objective of this clinical case report is to demonstrate how cardiac point-of-care ultrasound was pivotal in the clinical course of a seemingly well neonate with vague symptoms. A 6-week-old male infant presented to the emergency department with fatigue and pallor that was reported to have resolved before arrival. In the emergency department, he had a normal physical examination and stable vital signs. Cardiac point-of-care ultrasound was performed and demonstrated a mass near the mitral valve. These ultrasound findings prompted additional evaluation, cardiology consultation, admission, and subsequent diagnosis of a rhabdomyoma due to tuberous sclerosis.