Metabolic equivalent of task (MET) in the preoperative assessment in aortic surgery: a retrospective analysis

Background: Reliable prediction of the preoperative risk is of crucial importance for patients undergoing aortic repair. In this retrospective cohort study we evaluated the metabolic equivalent of task (MET) in the preoperative risk assessment with clinical outcome in a cohort of consecutive patients. Methods: : Retrospective analysis of prospectively collected data in a single center unit of 296 patients undergoing open or endovascular aortic repair. Out of these, 276 patients had a preoperative statement of their functional capacity in metabolic units and were evaluated concerning their postoperative outcome. Results: : Mean survival of the whole cohort was 74 months. There was no significant difference between patients with a functional capacity of more or less than 4 MET respectively (74.5 vs 65.4 months; p=0.64). The infrarenal cohort was subdivided based on the operative technique (open or endovascular) and the preoperative MET status. Survival analysis of all four subgroups showed no significant differences. The median follow-up of the patients’ cohort was 10.8 months. In 46 patients with >4MET (20.9%) perioperative complications occurred compared to the group with 4MET was 7%. Conclusion: Functional preoperative evaluation by MET in patients undergoing aortic surgery is used as standardized tool for patients’ assessment and is meant to act as a useful surrogate marker of perioperative performance. However, it could not discern patients in need for cardiopulmonary testing. Trial registration: clinicaltrials.gov, registration number NCT03617601 (retrospectively registered)