NYHA Functional Class: Explanation and Clinical Context The NYHA (New York Heart Association) Functional Classification is a widely used system to assess the severity of heart failure symptoms and their impact on physical activity. It classifies patients into four categories: Class I (no limitation of physical activity), Class II (slight limitation), Class III (marked limitation), and Class IV (symptoms at rest). This classification helps clinicians in risk stratification, therapeutic decision-making, and monitoring disease progression. Although subjective, it is a cornerstone in heart failure management and clinical trials.
Reference:
Yancy CW, Jessup M, Bozkurt B, et al. 2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure. J Am Coll Cardiol. 2017;70:776–803. doi:10.1016/j.jacc.2017.04.025
McMurray JJ, et al. ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2021. Eur Heart J. 2021;42:3599–3726. doi:10.1093/eurheartj/ehab368