The 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ-23) is formally qualified by the Food and Drug Administration as a valid patient-reported outcome measure for use in heart failure (HF) clinical trials, although its length may increase respondent burden. A pooled participant-level analysis published in the Journal of the American College of Cardiology evaluated whether the shorter 12-item version (KCCQ-12), originally developed in HF with reduced left ventricular ejection fraction (HFrEF), performed similarly in patients with HF with mildly reduced or preserved left ventricular ejection fraction (HFmrEF/HFpEF).

Data were pooled from four randomized clinical trials: TOPCAT, PARAGON-HF, DELIVER, and FINEARTS-HF. Among 18,216 participants, the mean age was 72 ± 9 years, 46% were women, 72% had New York Heart Association functional class II symptoms, the mean left ventricular ejection fraction was 55 ± 8%, and the median N-terminal pro-B-type natriuretic peptide was 987 pg/mL (IQR 517–1,781).

All trials collected KCCQ-23 overall summary scores (OSS) at baseline and follow-up visits. KCCQ-12 OSS were derived from corresponding KCCQ-23 items. Both scores ranged from 0 (worst) to 100 (best). Baseline KCCQ-23 OSS was 65.5 ± 21.4, compared with 64.1 ± 21.7 for KCCQ-12.

KCCQ-12 strongly correlated with KCCQ-23 at baseline (Spearman ρ = 0.987), with consistent findings across major subgroups and follow-up visits (all ρ > 0.980). Prognostic discrimination for cardiovascular death and HF hospitalization was comparable between tools (C-index 0.583 for KCCQ-23 vs 0.586 for KCCQ-12).

Treatment effects of HF therapies on questionnaire scores were similar across all trials and time points, with differences of less than 1 point on the 0 to 100 scale.

The findings suggest KCCQ-12 closely paralleled KCCQ-23 and may offer a lower-burden alternative for patient-reported outcome assessment in HF clinical trials involving HFmrEF and HFpEF.