• coronary arteries
• arterie coronarie
• prepartecipation screening for sport activities
• young athletes
• giovani atleti
• sudden cardiac death
• ecocardiografia
• morte cardiaca improvvisa
• echocardiography
• high take-off
• origin anomalies of coronary arteries
• anomalie coronariche
• coronary artery anomalies
• anomalie di origine delle arterie coronarie

Echocardiographic screening of anomalous coronary artery origin is of increasing interest for children participating in sport activities. However, criteria to define normal coronary artery origins in children are poorly defined. Thus, the aim of the present investigation is to define the normal origin and angle of emergence of coronary arteries by echocardiography in healthy children. Materials and methods: The distances of the left main and right coronary artery (LMCA, RCA) origins from the aortic annulus were measured in the parasternal long-axis view (LAX). The angle of coronary artery emergence was measured in the parasternal short-axis view (SAX). Results: A total of 700 healthy subjects (mean age: 9.53 ± 5.95 years; range: 1 day–17.98 years) were prospectively enrolled. The distance of the RCA and LMCA from the aortic annulus correlated with body surface area, and nomograms (Z-scores) were generated. The RCA origin was below the sinotubular junction (STJ) in 605 patients (86.43%), at the STJ in 66 patients (9.43%), and above the STJ in 29 patients (4.14%). The LMCA origin was below the STJ in 671 patients (95.86%), at the STJ in 12 patients (1.71%), and above the STJ in 17 patients (2.43%). With respect to the RCA, an emergence angle < 18.5° in the SAX predicted a high take-off. with a sensitivity of 98.3% and a specificity of 93.1% (AUC 0.998). With respect to the LMCA, an emergence angle > 119.5° in the SAX predicted a high take-off, with a sensitivity of 70.6% and a specificity of 82.4% (AUC 0.799). Conclusion: This study establishes nomograms for LMCA and RCA origin in standard echocardiographic projections in healthy children.