Abstract 12019: The Psychometric Performance of the Kansas City Cardiomyopathy Questionnaire-12 in Symptomatic Obstructive Hypertrophic Cardiomyopathy

Abstract

Background: A treatment goal for obstructive hypertrophic cardiomyopathy (oHCM) is to reduce symptom burden and improve health status, which can be measured with the 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ-23). While the KCCQ-23 has been validated in oHCM, the shorter 12-item version (KCCQ-12) is more feasible in clinical care but has not been validated. Hypothesis: The construct validity, reliability, and responsiveness of the KCCQ-12 will support its use for patients with oHCM. Aims: To validate the psychometric performance of the KCCQ-12 in patients with oHCM and its interpretability categorized by Patient Global Impression of Change (PGIC). Methods: The psychometric properties of the KCCQ-12 and domains were tested in 196 participants with symptomatic oHCM from the EXPLORER-HCM trial. Construct validity was assessed against clinical and patient-reported standards using Spearman Correlation coefficients. Reliability was assessed by Cronbach’s alpha (> 0.70). Test-retest reliability was determined using intra-class correlation (ICC) coefficient (good correlation being ICC > 0.70) and paired t-tests of clinically stable patients (defined as no change in PGIC from baseline to 6 weeks and no change in Patient Global Impression of Severity from 18-30 weeks). Responsiveness and interpretability were assessed within categories of the 6-week PGIC. Results: KCCQ-12 domains and summary scores had moderate to strong correlations with most clinical standards (NYHA class, exercise duration, pVO 2 ) and patient-reported scales (Table 1). The KCCQ-12 showed strong internal and test-retest reliability (Table 2). All KCCQ-12 scores demonstrated significant and proportional changes of different magnitudes of clinical change delineated by the PGIC (Table 3). Conclusion: The KCCQ-12 demonstrates good psychometric performance for patients with oHCM and can be confidently used to monitor the health status of patients with oHCM in clinical practice.