The Psychometric Performance of the Kansas City Cardiomyopathy Questionnaire-12 in Symptomatic Obstructive Hypertrophic Cardiomyopathy.

Background: A primary goal of treating patients with obstructive hypertrophic cardiomyopathy (oHCM) is to improve their symptoms, function and quality of life. Although the psychometric properties of the 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ-23) have been described in oHCM, they have not been assessed for the shorter 12-item version (KCCQ-12), which is used increasingly in clinical practice.

Methods and results: Using data from the EXPLORER-HCM trial, the psychometric properties of the KCCQ-12 were evaluated. The KCCQ-12 domain and summary scores had moderate correlations with the most relevant clinical (New York Heart Association class, exercise duration, peak oxygen consumption) and patient-reported measures (EQ-5D-5L visual analog scale, Work Productivity and Activity Impairment [WPAI] questionnaire, and Hypertrophic Cardiomyopathy Symptom Questionnaire [HCMSQ]). KCCQ-12 domain scores had strong internal consistency, and test-retest reliability, demonstrated significant and proportional changes with differing magnitudes of clinical change (assessed by the patients' global impressions of change and the patients' impressions of severity), and they demonstrated close equivalence to the KCCQ-23 scores.

Conclusions: The KCCQ-12 demonstrated good psychometric performance for patients with oHCM, comparable to that of the KCCQ-23, supporting its use in clinical practice to care for patients with oHCM.