Association between functional Status and cardiac function in chronic heart failure: insights from the C-MIC II Trial

Area of Science:

• Cardiology
• Clinical Trials
• Heart Failure Research

Background:

• The relationship between cardiac function, functional capacity, and patient-reported health status in heart failure (HF) is not fully understood.
• This knowledge gap impacts endpoint selection and understanding treatment response in HF clinical trials.

Purpose of the Study:

• To analyze the correlations between changes in patient-reported health status, functional capacity, and cardiac function in patients with chronic heart failure.
• To determine how different clinical domains reflect treatment response in advanced HF.

Main Methods:

• A post hoc analysis of the C-MIC II trial involving 65 patients with chronic HF and reduced ejection fraction (NYHA Class III-IV).
• Evaluated correlations between changes in Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OSS), 6-minute walk distance (6MWD), core lab-assessed left ventricular ejection fraction (LVEF), and peak oxygen uptake (peak VO2) over 6 months.

Main Results:

• Changes in KCCQ-OSS and 6MWD showed modest correlations with LVEF (r=0.39 for both).
• KCCQ-OSS and 6MWD changes correlated strongly with each other (r=0.63).
• LVEF changes demonstrated a modest correlation with peak VO2 changes (r=0.41).

Conclusions:

• In advanced HF, improvements in health status and submaximal functional capacity are modestly associated with LVEF.
• LVEF correlates more closely with peak oxygen uptake.
• Cardiac function, functional capacity, and health status are distinct yet related domains, supporting multidimensional assessment in HF trials.