Intramyocardial Bridge in Sports Medicine: Proposal of a Possible Follow-Up Strategy in Asymptomatic Athletes

Background: Intramyocardial bridge (MB) is a coronary anomaly characterized by a segment of the artery tunneling within the myocardium. While often asymptomatic, it may lead to ischemic events. Despite traditional disqualification from competitive sports, 2023 guidelines now permit participation for athletes with MBs that do not meet specific high-risk morphological criteria. This study aims to evaluate a novel combined provocative test, integrating Cardiopulmonary Exercise Testing (CPET) and stress echocardiography for the assessment of myocardial deformation (twist), to assess the functional impact of MB in asymptomatic athletes. Methods: This cross-sectional case-control study included 18 participants (nine cases with "significant" MB diagnosed via Computed Tomography (CT) coronary angiography and nine healthy, trained controls), aged 18-78 years. All subjects underwent evaluation at our facility for competitive certification. Assessment protocols included resting echocardiography, Global Longitudinal Strain (GLS), and Cardiopulmonary Exercise Testing (CPET) to quantify exercise capacity and dynamic myocardial function. Results: No significant differences in echocardiographic parameters were observed between groups at rest. However, during exercise, athletes with MB demonstrated a significant reduction in GLS and ventricular twist compared to the control group. These findings indicate a notable loss of apical reserve in the MB cohort during physical stress. Conclusions: The integration of CPET and myocardial deformation analysis provides an effective diagnostic tool for identifying functional impairment in asymptomatic athletes with MB. This combined approach offers a superior follow-up strategy for managing athletes who may be at risk for ischemic events despite lack of clinical symptoms.