Twenty-nine year old man with a history of complete repair of Tetralogy of Fallot (TOF) at the age of 5 was seen at outpatient clinic suffering from exertional dyspnea. His blood pressure was 110/70 mmHg, pulse 82 beats per minute and respiratory rate of 16 breaths per minute. His oxygen saturation was 90 % under room air. Auscultation exposed a 3/6 systolic ejection murmur at the left sternal border. Electrocardiogram (ECG) showed sinus rhythm with right ventricular hypertrophy (RVH) and right bundle branch block (RBBB). The transthorasic echocardiography (TTE) was applied. RVH and stenosis of the right ventricular outflow tract (RVOT) with a pressure gradient of 45 mmHg were obtained. Mass shaped lesion was seen in right ventricular apex during TTE examination. Right ventricular papillary muscle hypertrophy was the final diagnosis after transeosephageal echocardiography (TEE) and repeated TTE (Figure 1 and 2). Tetralogy of Fallot is the most common cyanotic congenital heart disease, consisting 10% of all congenital heart malformations. TOF includes four major component which are ventricular septal defect (VSD), overriding aorta, RVOT obstruction and RVH. Echocardiography is an indispensable method for organizing treatment and diagnosis of the disease.