A 10-year-old boy was admitted to the hospital with a cardiac murmur for 8 years. The patient had no previous history of cyanosis, squatting, syncope, hemoptysis, chest pain, or recurrent pneumonia, and showed shortness of breath after activity since the age of 6. In August 2022, the patient was hospitalized in our department of cardiology with a diagnosis of "pneumonia, septic pericarditis, infective endarteritis, hydropericardium and pleural effusion", and no pulmonary aneurysm was detected by cardiac ultrasound and chest CT several times during the hospitalization. The boy was diagnosed with infective endarteritis because of positive blood culture (micrococcus luteus), high white blood cell count (28.28 x 109/l), and echocardiogram indicating vegetation in the left pulmonary artery. We administered anti-infective therapy according to the guidelines of infective endocarditis, waited for a negative blood culture result, followed by a full course of antibiotics for more than 4 weeks before proceeding with surgery. He was discharged after 17 days of anti-infective treatment and was continued on oral linezolid for 18 days. In September 2022, a follow-up chest CT showed a significantly enlarged cardiac shadow, and most of the pericardial and pleural effusions were absorbed. The follow-up chest x-ray from August to November is shown in Figure 1. The following were the results of the physical examination performed on admission: there was no differential cyanosis in the upper and lower extremities, thrill could be felt, persistent mechanical murmur could be heard between the second and third ribs at the left edge of the sternum, there was accentuation of P2 cardiac sound without fixed splitting, there were no clubbed fingers, and there was congenital absence of the left hand. An echocardiogram performed on 14 November 2022, revealed patent ductus arteriosus, with a left-to-right shunt flowing at 4.2 m/s; a mild tricuspid regurgitation flowing at 2.4 m/s; the size of the pulmonary artery was 31 x 19 mm, with an inner diameter of 9.8 mm; a strong echogenicity of 3 x 5 mm in size was detected at the opening of the left pulmonary artery. A cardiac CT angiography (CTA) revealed that the size of the pulmonary artery was 31 x 26 x 25 mm, and the end of the pulmonary artery of the patent ductus arteriosus was 5.8 x 4.8 mm (Figure 2). The electrocardiograph (ECG) showed sinus rhythm with high left ventricular voltage and electrical gradients in the QRS wave (QRS) wave group. Preoperative routine blood test, blood biochemical examination, CRP, hematocrit, syphilis screening, and tuberculosis screening showed no significant abnormalities.
We performed the surgery, which lasted for over 9 hours. We performed a median sternotomy and found severe pericardial adhesions; possibly the boy had pericarditis due to infective endarteritis. After instituting cardiopulmonary bypass, we freed along the distal pulmonary trunk, and its surrounding tissues were severely adherent and not easily identifiable. Thus, we decided to lower the anal temperature to 18 C in preparation for deep hypothermic circulatory arrest; the heart and cardiopulmonary bypass were arrested with del Nido cardioplegia through the aortic root. A longitudinal incision was made in the pulmonary trunk to identify the pulmonary artery end of the ductus arteriosus, the diameter of which was 10 mm. We used a bovine pericardial patch (Balance Medical) to repair the defect from the medial aspect of the pulmonary artery. After freeing the structures surrounding the pulmonary artery aneurysm, the aneurysm was seen to be approximately 30 mm in diameter and spherical in shape (Figure 3). A dissection of the aneurysm revealed no vegetations inside it or at the opening of the left pulmonary artery. After complete resection of the aneurysm, the pulmonary trunk was repaired with a bovine pericardial patch (Balance Medical) and continuous sutures with 5-0 Prolene sutures. The temperature was increased, the aorta was deaired, and the aortic clamp was removed. The anastomosis of the bovine pericardial patch oozed blood significantly, and repeated reinforcement and trimming of the pulmonary artery wall around the aneurysm proved ineffective. During the fourth aortic cross-clamp, a complete resection of the pulmonary aortic wall around the aneurysm was done, and a reconstruction of the pulmonary artery trunk with the bovine pericardium patch was carried out, following which the bleeding abated, the circulation finally stabilized, gauze compression was applied to stop bleeding, and the closure of the chest was delayed. The cardiopulmonary bypass time was 382 min. The aortic cross-clamp time was 60 + 36 + 2 + 69 min, 167 min in total. The deep hypothermic circulatory arrest time was 37 min. An intraoperative transesophageal echocardiography showed a patent pulmonary artery flow. After the operation, the patient was admitted to the cardiac intensive care unit (CCU), and the chest was closed successfully on the third postoperative day.
The patient's surgery was successful with no serious complications. The postoperative cardiac CTA revealed that the pulmonary aneurysm disappeared, the pulmonary artery flow was patent, and the pulmonary artery trunk was significantly reduced (Figure 4). A pathological examination of the pulmonary artery aneurysm showed a vascular wall-like structure with a smooth inner layer and uneven thickness with varying degrees of fibrosis and mucoid degeneration, and a focal infiltration of acute and chronic inflammatory cells could be seen in the thick position. The boy reported no abnormal results on the postoperative follow-up echocardiogram at 1, 3, and 6 months. The CT scan also showed a smooth PA reconstruction and no aneurysm on the pulmonary artery.