As heart failure progresses, it becomes harder for patients to eliminate carbon dioxide that accumulates in the blood. This relationship between ventilatory volumes and CO2 elimination is called ventilatory, or breathing, efficiency, and is measured by the Shape-HF.
Breathing efficiency measurements add resolution to the New York Heart Failure Association classification system for heart failure by providing a full range of values that make the assessment more sensitive and specific.
This ventilatory classification system reflects changes in patient physiology well before the onset of, or change in, overt symptoms. With this information, physicians can make suitable therapy decisions based on objective patient physiology.
Breathing efficiency measurements
provide the most sensitive
and specific measure of