OBJECTIVES: Current literature on AAA is characterized by selective outcome reporting, while guideline recommendations are frequently based on studies of poor methodological quality. To improve evidence synthesis, standardization of outcome measures through a core outcome set (COS) is advocated, particularly in artificial intelligence (AI) research. A COS consists of essential outcomes for reporting in clinical research based on patient and expert consensus. This study aimed to create a COS for research on patients with AAA under surveillance. This COS will be innovatively applied in AI research focused on cardiovascular disease progression. METHODS: First, a longlist of AAA outcomes was identified through a systematic literature search and focus groups with patients, caregivers, and healthcare professionals. A three-round European Delphi survey was subsequently conducted with patients and healthcare professionals. In an expert consensus meeting with key opinion leaders and patients, the COS was finalized. RESULTS: The 91-outcome AAA longlist was used in the Delphi study, in which 104 patients and 153 healthcare professionals participated. The highest-rated outcomes from the third Delphi round were discussed in the expert consensus meeting, attended by 23 key opinion leaders, two patients and one patient representative from a patient society. Ten core pre- and postoperative outcomes were chosen across six health domains, with AAA rupture, survival, health-related quality of life, clinical success, and graft infection attaining 100% consensus for inclusion in the COS. CONCLUSION: This COS consists of ten outcomes and should be implemented in clinical and AI research on AAA under surveillance.