Conclusions
These findings highlight the interpretive limitations associated with the subjective assessment of patient frailty with surgical risk classification underestimated in up to a third of patients compared to the more objective validated assessment of post-operative outcomes via CPET-derived CRF. For ‘high-stakes’ open TAAA surgery, the integration of CPET can improve perioperative risk assessment though further research is required to identify ‘lower limits’ of CRF below which operative intervention may be considered prohibitively risky. Surgeons also need to consider (pre-operative) exercise training as a modifiable component of multimodal prehabilitation strategies with the potential to augment CRF, reduce surgical risk and thus improve outcome.