Complications associated with myocardial bridging in four children without underlying cardiac disease: a case series.

Background: Myocardial bridging is largely considered to be a benign, symptomless congenital anomaly of the coronary arteries in which the intramyocardial coronary course is partially 'tunnelled' and leads to vessel compression during ventricular systole. There are few data regarding children.Objective: To report on myocardial bridging observed in children seeking medical help in the paediatric emergency room.Case presentation: A series of four children aged 6-13 years with symptomatic myocardial bridging but no other underlying cardiac abnormalities is reported. They were admitted to the paediatric emergency department during 2013-2016, three with chest pain after physical activity and one with septic shock.Results: Heart computed tomography scan in the first three demonstrated myocardial bridging of the left anterior descendent coronary artery's branches; their 2-year follow-up was uneventful. The fourth patient presented with ventricular fibrillation 24 hours after admission and at autopsy there was an intramyocardial tract 4 cm long on the left anterior descendent coronary artery.Conclusions: This case series demonstrates that myocardial bridging can be symptomatic in children with no underlying cardiac disorders and should be included in the differential diagnosis of exertional chest pain and/or arrhythmias.Abbreviations: CRP, C-reactive protein; CT, computed tomography; D1, diagonal 1 artery; ECG, electrocardiogram; ED, emergency department; KD, Kawasaki disease; LAD, left anterior descending coronary artery; MB, myocardial bridging; RI, ramus intermedius artery; TN, troponin.