(A) Preoperative transthoracic echocardiogram apical 4-chamber view showing mitral regurgitation and no ventricular septal defect. (B) Preoperative trans-thoracic echocardiogram apical 4-chamber view showing elongated membranous septum. (C) Postoperative transthoracic echocardiographic apical 4-chamber view showing a ventral septal defect with a left–right shunt on colour Doppler. (D) Postoperative transthoracic echocardiographic apical 4-chamber view with inferior angulation showing ventricular septal defect with left–right shunt on colour Doppler. MR: mitral regurgitation; TTE: transthoracic echocardiography; VSD: ventricular septal defect.