Assessment of readiness for return to skiing after coronary artery bypass grafting and left ventricular reconstruction using cardiopulmonary exercise testing and field-based expiratory gas analysis: a case report.

BACKGROUND: Returning to skiing after myocardial infarction and complex cardiac surgery is challenging because cardiopulmonary exercise testing (CPET) performed in laboratory settings may not fully reflect real-world sports-specific demands. CASE SUMMARY: A 63-year-old male ski instructor experienced an acute myocardial infarction while skiing and subsequently underwent coronary artery bypass grafting combined with surgical ventricular restoration. After structured outpatient cardiac rehabilitation incorporating high-intensity interval training, serial CPET demonstrated an improvement in peak oxygen uptake from 19.4 to 22.1 mL/kg/min without adverse events. To assess real-world cardiopulmonary stress, a field-based breath-by-breath expiratory gas analysis was performed during skiing using a portable metabolic analyser. Three ski techniques (skidding, long radius carving, and short radius carving) were evaluated. Peak oxygen uptake and heart rate during all ski conditions did not exceed the corresponding peak values obtained during CPET or the prescribed high-intensity interval training intensity, indicating that skiing was performed within the predefined physiological safety margin. DISCUSSION: This case demonstrated a clinically applicable strategy for assessing readiness for return to skiing by integrating CPET-guided rehabilitation with field-based physiological assessment, thereby enabling objective evaluation of sport-specific safety.