Cardiff cardiac ablation patient-reported outcome measure (C-CAP): validation of a new questionnaire set for patients undergoing catheter ablation for cardiac arrhythmias in the UK.

PURPOSE: To formally test and validate a patient-reported outcome measure (PROM) for patients with cardiac arrhythmias undergoing catheter ablation procedures in the UK [Cardiff Cardiac Ablation PROM (C-CAP)]. METHODS: A multicentre, prospective, observational cohort study with consecutive patient enrolment from three UK sites was conducted. Patients were sent C-CAP questionnaires before and after an ablation procedure. Pre-ablation C-CAP1 (17 items) comprised four domains: patient expectations; condition and symptoms; restricted activity and healthcare visits; medication and general health. Post-ablation C-CAP2 (19 items) comprised five domains including change in symptoms and procedural complications. Both questionnaires also included the generic EQ-5D-5L tool (EuroQol). Reliability, validity, and responsiveness measures were calculated. RESULTS: A total of 517 valid pre-ablation and 434 post-ablation responses were received; questionnaires showed good feasibility and item acceptability. Internal consistency was good (Cronbach's alpha >0.7) and test-retest reliability was acceptable for all scales. C-CAP scales showed high responsiveness (effect size >0.8). Patients improved significantly (p < 0.001) following ablation across all disease-specific and global scales. Minimal clinically important difference was calculated. Improvement beyond the smallest detectable change of 9 points (symptom severity scale), 3 points (frequency and duration of symptoms scale), and 8 points (impact on life scale) indicates an important change. Amendments to the C-CAP questionnaires were identified through the validation process and made to produce the final tools. CONCLUSIONS: The final C-CAP questionnaires are valid, reliable, and responsive tools for measuring symptom change, impact, and expectations in patients undergoing ablation for cardiac arrhythmias. C-CAP questionnaires provide a tool with disease-specific and generic domains to explore how cardiac ablation procedures in the UK impact upon patients' lives.