Surgical unroofing of long and deep myocardial bridges in children: A 2-case report

INTRODUCTION: Myocardial bridge (MB) is a congenital coronary artery malformation, generally considered benign. However, we reported 2 cases of long and deep coronary MB in children and their surgical treatment. PATIENT CONCERNS AND DIAGNOSIS: Two children with coronary MB presented with syncope as the initial symptom. Case 1: female, 11 years old, body weight 32.5 kg. Cardiac enzymes were elevated. Electrocardiograms showed ST-T changes. Echocardiography: No abnormalities were found in cardiac function and ventricular wall motion. Coronary computed tomography angiography (CCTA) showed that the left anterior descending artery (LAD) and its branches were located deep and long within the myocardium. Coronary angiography (CAG) revealed that the LAD was nearly occluded during systole and thin during diastole, and the right coronary artery was small. Case 2: male, 12 years old, body weight 32 kg. Cardiac enzymes were elevated. Electrocardiograms showed abnormal Q waves, and the inferior and anterior ventricular walls were elevated in ST-segment. Regional wall motion abnormality and diastolic dysfunction were shown in echocardiography. CCTA showed the LAD and its branches were located deep and long within the myocardium. CAG showed that the LAD was slender in diastole and further narrowed in systole, while the right coronary artery ran short. INTERVENTIONS: Both cases were given surgical MB release. OUTCOMES: In case 1, postoperative reexamination showed the MB was completely released, and postoperative cardiac enzymes, electrocardiograms, echocardiograms, and CCTA demonstrated the patient was gradually recovering. The 3-month follow-up found nothing abnormal detected. In case 2, partial release was performed. The LAD was located in the middle and inner part of the interventricular septum. Partial release was performed at the proximal end, while complete release was performed at the middle and distal ends. The cardiac enzymes and electrocardiograms in the 3-month postoperative follow-up examination indicated the patient recovered, while the cardiac echocardiogram revealed that there was still regional wall motion abnormality and diastolic dysfunction. CONCLUSION: MB in children can cause syncope and myocardial infarction. Surgical unroofing of MB is an effective clinical option. Careful preoperative examination, including CCTA and CAG, and a detailed surgical planning system are critical to the surgery.