Validation of the Kansas City Cardiomyopathy Questionnaire in Patients with Tricuspid Regurgitation: The Tri-QOL Study

ImportanceImproving patients health status is a key goal of treating tricuspid regurgitation (TR). The Kansas City Cardiomyopathy Questionnaire (KCCQ) is a heart-failure disease specific health status measure that has been used to capture the health status impact of TR and the benefit of transcatheter tricuspid valve intervention (TTVI), but its validity in this clinical setting is unknown. ObjectiveTo evaluate the psychometric properties of the KCCQ in patients with TR. Design, Setting, ParticipantsData were pooled from patients with severe TR enrolled in 11 manufacturer-sponsored trials of TTVI. The data were transferred to the FDA to harmonize and anonymize prior to analysis by an independent center. Prespecified analyses included evaluation of internal consistency, reproducibility, responsiveness, construct validity, and prognostic validity. ResultsThe study cohort comprised 2693 patients (mean age 79{+/-}8 years, 62% women, mean baseline KCCQ Overall Summary [KCCQ-OS] score 50{+/-}23), enrolled in either single-arm (n=1517) or randomized (n=1176) investigations of TTVI. There was strong internal consistency within individual domains (Cronbachs alpha 0.77-0.83). Among clinically stable patients between 1 and 6 months, there were small mean changes in KCCQ domain and summary scores (differences of -0.1 to 1.9 points), demonstrating reproducibility. In contrast, domain and summary scores of patients who underwent TTVI showed large improvements at 1-month after treatment (mean changes 12.1-21.4 points), indicating excellent responsiveness. Construct validity was moderately-strong to strong when the domains were compared with best available reference measures (Spearman correlations 0.47-0.69). The KCCQ-OS was strongly associated with clinical events, with lower scores being associated with an increased risk of mortality (HR 1.34 per 10-point decrement, 95% CI 1.22-1.47) and heart failure hospitalization (HR 1.24 per 10-point decrement, 95% CI 1.17-1.31). Conclusions and RelevanceThe KCCQ has strong psychometric properties, including reliability, responsiveness, and validity in patients with severe TR. These data support its use in clinical investigations of TTVI as a measure of the impact of treatment on patients symptoms, function, and quality of life. KEY POINTSO_ST_ABSQuestionC_ST_ABSIs the Kansas City Cardiomyopathy Questionnaire (KCCQ) a valid disease-specific health status measure in patients with severe tricuspid regurgitation (TR)? FindingsData on 2693 patients from 11 clinical trials of various transcatheter tricuspid valve interventions (TTVI) from 2 device manufacturers were pooled and then analyzed by an academic analytic center. We found that the KCCQ has strong psychometric properties, including reliability, responsiveness, and validity in patients with severe TR. MeaningThese data support continued use of the KCCQ in clinical trials of TTVI as a measure of the impact of treatment on patients symptoms, function, and quality of life.