In the afternoon of 29th, we successfully completed the arterial catheter failure closure surgery for a low age and small weight child. The child was 81 days old, weighed 4.5 kg, the arterial duct had not been closed since birth, feeding was difficult, weight gain was slow, and he came to our department showing a typical continuous murmur at the left edge of the sternum in the precordial region, chest X-ray showed an enlarged heart shadow, prominent pulmonary artery segment, ultrasonography showed an unclosed arterial duct of 3.5 mm, and severe pulmonary hypertension. However, the child’s age and weight are small, and the arterial duct is relatively thick, so the operation is difficult and risky, and the treatment by occlusion is extremely risky for both the patient and the doctor. On the other hand, the child’s physical condition was difficult to tolerate open-heart surgery. After communication with the parents, we developed a special surgical plan and chose a small-sized catheter for blockage. The patient recovered well after the surgery and was discharged today. The parents said that they had been crying while waiting for the operation, and once they heard that the operation was completed successfully, they left tears of excitement and could never forget the doctor’s dedication.