A Composite Echocardiographic Index of Global Cardiac Remodeling in Athletes: Global Athletic Heart Index (GAHI)

Elite athletes develop physiological cardiac remodeling, involving both ventricular and atrial chambers, as well as wall thickening. We propose a Global Athletic Heart Index (GAHI) which integrates both ventricular and atrial changes, aiming to define with a simplified marker the physiologic cardiac remodeling and its relationship with aerobic performance in athletes. Six hundred forty-one healthy Olympic athletes (mean age 25.5 ± 5.3 years; 51% male) underwent transthoracic echocardiography and cardiopulmonary exercise testing. GAHI was calculated as the mean ratio of each chamber dimension to its sex-specific upper limit of normal. Athletes were classified as GAHI >1 (global cardiac remodeling) or ≤1. VO₂ max >85% of predicted was considered and indicator of preserved aerobic capacity. Sensitivity, specificity, and predictive values of GAHI >1 for identifying preserved VO₂ max were evaluated. Linear regression analyses assessed the association of GAHI with peak VO₂ and O₂ pulse. Overall, 155 athletes (24.2%) had GAHI >1. Endurance athletes were overrepresented in this group (51% vs 13%, p <0.0001). GAHI >1 was associated with larger LV and RV dimensions, higher LV mass, balanced biatrial enlargement, and preserved systolic and diastolic function. Cardiopulmonary exercise testing revealed higher peak VO₂, O₂ pulse, and workload (all p <0.0001). Linear regression analyses demonstrated significant positive associations between GAHI and peak VO₂ (R² = 0.24, p <0.0001) and O₂ pulse (R² = 0.20, p <0.0001). Using a dichotomous threshold, GAHI >1 identified athletes with VO₂ max >85% with 25.7% sensitivity, 93.9% specificity, 98.1% positive predictive value, and 9.5% negative predictive value. GAHI is an integrative marker of balanced cardiac remodeling closely associated with aerobic performance. A GAHI >1 reliably identifies athletes with balanced structural adaptations and preserved exercise capacity. GAHI may serve as a practical tool for athlete screening and individualized cardiovascular assessment.