Construct and Predictive Validity of the Kansas City Cardiomyopathy Questionnaire in Adult Congenital Heart Disease

The Kansas City Cardiomyopathy Questionnaire (KCCQ) is an Food and Drug Administration-approved health status measure for patients with heart failure (HF) but has not been directly assessed in adult congenital heart disease (ACHD).

This study evaluates construct and predictive validity of the KCCQ in ambulatory ACHD patients.

We performed cross-sectional and prospective cohort studies of ACHD patients who completed the KCCQ to assess construct and predictive validity, respectively. KCCQ scores were compared across ACHD complexity categories, disease characteristics and physiologic failure, and within 2 primary composite outcomes: death or all-cause hospitalization (DH) and death or interventional cardiac procedures (DP). Survival analysis was performed for each composite outcome.

A total of 109 patients completed 129 KCCQs (median age 29.0 years; 41.3% female). Median KCCQ scores were significantly lower for anatomically complex patients (76.6 in great complexity, 89.0 in simple/moderate complexity; P = 0.015), advanced ACHD physiological stage (72.6 in D, 98.0 in A; P < 0.001), patients with physician-reported HF (72.2 vs 87.2 without HF; P < 0.001), and advanced NYHA functional class (NYHA III: 44.4, NYHA I: 96.5; P < 0.001). Median follow-up time was 16.3 months in the predictive validity analysis (N = 92). KCCQ was significantly lower for ACHD patients who experienced DH (66.0 vs 85.0; P = 0.002) or DP (53.5 vs 85.0; P = 0.001). Patients scoring ≤50 had significantly worse event-free survival (P = 0.004 for DH; P = 0.001 for DP).

The KCCQ has construct and predictive utility in ACHD and provides an opportunity to assess health status in ACHD both clinically and in future ACHD research.