Weber Classification (CPET Functional Class) Calculator

Weber Classification (CPET Functional Class): Explanation and Clinical Context The Weber classification categorizes patients with chronic heart failure based on peak oxygen consumption (peak VO₂) measured during cardiopulmonary exercise testing (CPET). Class A corresponds to peak VO₂ > 20 mL/kg/min, indicating near-normal exercise capacity and favorable prognosis. Class B (16–20 mL/kg/min) indicates mild limitation of exercise and relatively favorable prognosis.

Class C (10–16 mL/kg/min) indicates moderate limitation and intermediate prognosis. Class D (< 10 mL/kg/min) indicates severe limitation and poor prognosis. This classification helps clinicians assess functional capacity, guide therapy, and estimate risk in patients with heart failure.