Background: Disease specific questionnaires are increasingly being used to evaluate treatment outcomes from the perspective of patients. There are currently no validated questionnaires that measure patient reported outcomes after proximal thoracic aortic aneurysm surgery. Objectives: To develop and pilot a newly formulated patient focussed questionnaire that measures the patient’s health status and health related quality of life before and after proximal thoracic aortic aneurysm surgery. Methods: Based on a literature review, a thematic analysis of audio recorded patient interviews and expert clinical testimony, a pool of items was generated to form a new questionnaire instrument. Suitable patients who were scheduled for elective aortic surgery at Liverpool Heart and Chest Hospital were identified and invited to participate in the pilot study. Patients were asked to complete the questionnaire prior to surgery and then at 6 weeks and 3 months after their operation. The newly developed instrument underwent preliminary testing for its appropriateness, acceptability, feasibility, interpretability, precision, reliability and responsiveness. Results: Several items from the CROQ (Coronary Revascularisation Outcomes Questionnaire) formed the basis of the instrument, with the addition of 10 items derived from a newly formulated conceptual model of proximal thoracic aortic disease. The items were arranged into four domains (symptoms, physical, psychosocial and cognitive). Initial testing showed that the newly developed instrument performed to acceptable standards. It showed good internal consistency (Cronbach’s alpha results for all domains > 0.85), and test retest reliability (intraclass correlation coefficient for all domains > 0.85). In paired sample tests, the values in each domain led to statistically significant differences from baseline at either 6 weeks or 3 months (p < 0.05), supporting the construct validity and responsiveness of the instrument. Conclusions: The new instrument demonstrated satisfactory validity as well as good internal reliability and test retest reliability for each item across all four domains. The initial findings suggest that the measure is sensitive and responsive to the effects of surgical treatment for proximal thoracic aortic aneurysms.