Subtotal tumour resection is used to treat infants with congenital cardiac fibroma and medication-resistant ventricular arrhythmias; however, complete elimination of arrhythmogenic substrates has been unclear. A 4-month-old male infant with congenital cardiac fibroma and ventricular fibrillation underwent subtotal tumour resection and implantable cardioverter-defibrillator implantation. Five years later, angiography revealed impending compression of the left coronary artery. Elimination of the arrhythmogenic substrate was confirmed and the device was removed successfully.