Hypertrophic cardiomyopathy has the highest incidence rate among genetically inherited cardiac diseases. It develops as a result of mutations in genes in related to the sarcomere protein in cardiac muscle. Generally, this results in asymmetrical hypertrophy. Patients who are symptomatic and have a significantly narrow left ventricular undergo should receive surgical treatment, whereas patients with a sudden cardiac death risk should receive treatment with an implantable cardiac defibrillator. This paper presents an infant with hypertrophic cardiomyopathy who was recently identified as having a mutation that resulted in a deletion-insertion type framework shift in the gene MYBPC3, who had family history of sudden death at a young age, and received myectomy and treatment with an implantable cardiac defibrillator in the same session due to a severely narrowed left ventricular outflow tract.